;;; org-list.el --- Plain lists for Org              -*- lexical-binding: t; -*-
;;
;; Copyright (C) 2004-2022 Free Software Foundation, Inc.
;;
;; Author: Carsten Dominik <carsten.dominik@gmail.com>
;;	   Bastien Guerry <bzg@gnu.org>
;; Keywords: outlines, hypermedia, calendar, wp
;; Homepage: https://orgmode.org
;;
;; This file is part of GNU Emacs.
;;
;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;;; Commentary:

;; This file contains the code dealing with plain lists in Org mode.

;; The core concept behind lists is their structure.  A structure is
;; a snapshot of the list, in the shape of a data tree (see
;; `org-list-struct').

;; Once the list structure is stored, it is possible to make changes
;; on it that will be mirrored to the real list or to get information
;; about the list, using accessors and methods provided in the
;; library.  Most of them require the use of one or two helper
;; functions, namely `org-list-parents-alist' and
;; `org-list-prevs-alist'.

;; Structure is eventually applied to the buffer with
;; `org-list-write-struct'.  This function repairs (bullets,
;; indentation, checkboxes) the list in the process.  It should be
;; called near the end of any function working on structures.

;; Thus, a function applying to lists should usually follow this
;; template:

;; 1. Verify point is in a list and grab item beginning (with the same
;;    function `org-in-item-p').  If the function requires the cursor
;;    to be at item's bullet, `org-at-item-p' is more selective.  It
;;    is also possible to move point to the closest item with
;;    `org-list-search-backward', or `org-list-search-forward',
;;    applied to the function `org-item-beginning-re'.

;; 2. Get list structure with `org-list-struct'.

;; 3. Compute one, or both, helper functions,
;;    (`org-list-parents-alist', `org-list-prevs-alist') depending on
;;    needed accessors.

;; 4. Proceed with the modifications, using methods and accessors.

;; 5. Verify and apply structure to buffer, using
;;    `org-list-write-struct'.

;; 6. If changes made to the list might have modified check-boxes,
;;    call `org-update-checkbox-count-maybe'.

;; Computing a structure can be a costly operation on huge lists (a
;; few thousand lines long).  Thus, code should follow the rule:
;; "collect once, use many".  As a corollary, it is usually a bad idea
;; to use directly an interactive function inside the code, as those,
;; being independent entities, read the whole list structure another
;; time.

;;; Code:

(require 'cl-lib)
(require 'org-macs)
(require 'org-compat)

(defvar org-M-RET-may-split-line)
(defvar org-adapt-indentation)
(defvar org-auto-align-tags)
(defvar org-blank-before-new-entry)
(defvar org-clock-string)
(defvar org-closed-string)
(defvar org-deadline-string)
(defvar org-done-keywords)
(defvar org-drawer-regexp)
(defvar org-element-all-objects)
(defvar org-inhibit-startup)
(defvar org-loop-over-headlines-in-active-region)
(defvar org-odd-levels-only)
(defvar org-outline-regexp-bol)
(defvar org-scheduled-string)
(defvar org-todo-line-regexp)
(defvar org-ts-regexp)
(defvar org-ts-regexp-both)

(declare-function org-at-heading-p "org" (&optional invisible-ok))
(declare-function org-back-to-heading "org" (&optional invisible-ok))
(declare-function org-before-first-heading-p "org" ())
(declare-function org-current-level "org" ())
(declare-function org-element-at-point "org-element" ())
(declare-function org-element-context "org-element" (&optional element))
(declare-function org-element-interpret-data "org-element" (data))
(declare-function org-element-lineage "org-element" (blob &optional types with-self))
(declare-function org-element-macro-interpreter "org-element" (macro ##))
(declare-function org-element-map "org-element" (data types fun &optional info first-match no-recursion with-affiliated))
(declare-function org-element-normalize-string "org-element" (s))
(declare-function org-element-parse-buffer "org-element" (&optional granularity visible-only))
(declare-function org-element-property "org-element" (property element))
(declare-function org-element-put-property "org-element" (element property value))
(declare-function org-element-set-element "org-element" (old new))
(declare-function org-element-type "org-element" (element))
(declare-function org-element-update-syntax "org-element" ())
(declare-function org-end-of-meta-data "org" (&optional full))
(declare-function org-entry-get "org" (pom property &optional inherit literal-nil))
(declare-function org-export-create-backend "ox" (&rest rest) t)
(declare-function org-export-data-with-backend "ox" (data backend info))
(declare-function org-export-get-backend "ox" (name))
(declare-function org-export-get-environment "ox" (&optional backend subtreep ext-plist))
(declare-function org-export-get-next-element "ox" (blob info &optional n))
(declare-function org-export-with-backend "ox" (backend data &optional contents info))
(declare-function org-fix-tags-on-the-fly "org" ())
(declare-function org-get-todo-state "org" ())
(declare-function org-in-block-p "org" (names))
(declare-function org-inlinetask-goto-beginning "org-inlinetask" ())
(declare-function org-inlinetask-goto-end "org-inlinetask" ())
(declare-function org-inlinetask-in-task-p "org-inlinetask" ())
(declare-function org-inlinetask-outline-regexp "org-inlinetask" ())
(declare-function org-level-increment "org" ())
(declare-function org-mode "org" ())
(declare-function org-narrow-to-subtree "org" (&optional element))
(declare-function org-outline-level "org" ())
(declare-function org-previous-line-empty-p "org" ())
(declare-function org-reduced-level "org" (L))
(declare-function org-set-tags "org" (tags))
(declare-function org-show-subtree "org" ())
(declare-function org-sort-remove-invisible "org" (S))
(declare-function org-time-string-to-seconds "org" (s))
(declare-function org-timer-hms-to-secs "org-timer" (hms))
(declare-function org-timer-item "org-timer" (&optional arg))
(declare-function outline-next-heading "outline" ())
(declare-function outline-previous-heading "outline" ())


\f
;;; Configuration variables

(defgroup org-plain-lists nil
  "Options concerning plain lists in Org mode."
  :tag "Org Plain lists"
  :group 'org-structure)

(defcustom org-cycle-include-plain-lists t
  "When t, make TAB cycle visibility on plain list items.
Cycling plain lists works only when the cursor is on a plain list
item.  When the cursor is on an outline heading, plain lists are
treated as text.  This is the most stable way of handling this,
which is why it is the default.

When this is the symbol `integrate', then integrate plain list
items when cycling, as if they were children of outline headings.

This setting can lead to strange effects when switching visibility
to `children', because the first \"child\" in a subtree decides
what children should be listed.  If that first \"child\" is a
plain list item with an implied large level number, all true
children and grand children of the outline heading will be
exposed in a children' view."
  :group 'org-plain-lists
  :group 'org-cycle
  :type '(choice
	  (const :tag "Never" nil)
	  (const :tag "With cursor in plain list (recommended)" t)
	  (const :tag "As children of outline headings" integrate)))

(defcustom org-list-demote-modify-bullet nil
  "Default bullet type installed when demoting an item.
This is an association list, for each bullet type, this alist will point
to the bullet that should be used when this item is demoted.
For example,

 (setq org-list-demote-modify-bullet
       \\='((\"+\" . \"-\") (\"-\" . \"+\") (\"*\" . \"+\")))

will make

  + Movies
    + Silence of the Lambs
    + My Cousin Vinny
  + Books
    + The Hunt for Red October
    + The Road to Omaha

into

  + Movies
    - Silence of the Lambs
    - My Cousin Vinny
  + Books
    - The Hunt for Red October
    - The Road to Omaha"
  :group 'org-plain-lists
  :type '(repeat
	  (cons
	   (choice :tag "If the current bullet is  "
		   (const "-")
		   (const "+")
		   (const "*")
		   (const "1.")
		   (const "1)"))
	   (choice :tag "demotion will change it to"
		   (const "-")
		   (const "+")
		   (const "*")
		   (const "1.")
		   (const "1)")))))

(defcustom org-plain-list-ordered-item-terminator t
  "The character that makes a line with leading number an ordered list item.
Valid values are ?. and ?\\).  To get both terminators, use t.

This variable needs to be set before org.el is loaded.  If you
need to make a change while Emacs is running, use the customize
interface or run the following code after updating it:

  `\\[org-element-update-syntax]'"
  :group 'org-plain-lists
  :type '(choice (const :tag "dot like in \"2.\"" ?.)
		 (const :tag "paren like in \"2)\"" ?\))
		 (const :tag "both" t))
  :set (lambda (var val) (set var val)
	 (when (featurep 'org-element) (org-element-update-syntax))))

(defcustom org-list-allow-alphabetical nil
  "Non-nil means single character alphabetical bullets are allowed.

Both uppercase and lowercase are handled.  Lists with more than
26 items will fallback to standard numbering.  Alphabetical
counters like \"[@c]\" will be recognized.

This variable needs to be set before org.el is loaded.  If you
need to make a change while Emacs is running, use the customize
interface or run the following code after updating it:

  `\\[org-element-update-syntax]'"
  :group 'org-plain-lists
  :version "24.1"
  :type 'boolean
  :set (lambda (var val) (set var val)
	 (when (featurep 'org-element) (org-element-update-syntax))))

(defcustom org-list-two-spaces-after-bullet-regexp nil
  "A regular expression matching bullets that should have 2 spaces after them.
When nil, no bullet will have two spaces after them.  When
a string, it will be used as a regular expression.  When the
bullet type of a list is changed, the new bullet type will be
matched against this regexp.  If it matches, there will be two
spaces instead of one after the bullet in each item of the list."
  :group 'org-plain-lists
  :type '(choice
	  (const :tag "never" nil)
	  (regexp)))

(defcustom org-list-automatic-rules '((checkbox . t)
				      (indent . t))
  "Non-nil means apply set of rules when acting on lists.
\\<org-mode-map>
By default, automatic actions are taken when using
  `\\[org-meta-return]',
  `\\[org-metaright]',
  `\\[org-metaleft]',
  `\\[org-shiftmetaright]',
  `\\[org-shiftmetaleft]',
  `\\[org-ctrl-c-minus]',
  `\\[org-toggle-checkbox]',
  `\\[org-insert-todo-heading]'.

You can disable individually these rules by setting them to nil.
Valid rules are:

checkbox  when non-nil, checkbox statistics is updated each time
          you either insert a new checkbox or toggle a checkbox.
indent    when non-nil, indenting or outdenting list top-item
          with its subtree will move the whole list and
          outdenting a list whose bullet is * to column 0 will
          change that bullet to \"-\"."
  :group 'org-plain-lists
  :version "24.1"
  :type '(alist :tag "Sets of rules"
		:key-type
		(choice
		 (const :tag "Checkbox" checkbox)
		 (const :tag "Indent" indent))
		:value-type
		(boolean :tag "Activate" :value t)))

(defcustom org-list-use-circular-motion nil
  "Non-nil means commands implying motion in lists should be cyclic.
\\<org-mode-map>
In that case, the item following the last item is the first one,
and the item preceding the first item is the last one.

This affects the behavior of
  `\\[org-move-item-up]',
  `\\[org-move-item-down]',
  `\\[org-next-item]',
  `\\[org-previous-item]'."
  :group 'org-plain-lists
  :version "24.1"
  :type 'boolean)

(defvar org-checkbox-statistics-hook nil
  "Hook that is run whenever Org thinks checkbox statistics should be updated.
This hook runs even if checkbox rule in
`org-list-automatic-rules' does not apply, so it can be used to
implement alternative ways of collecting statistics
information.")

(defcustom org-checkbox-hierarchical-statistics t
  "Non-nil means checkbox statistics counts only the state of direct children.
When nil, all boxes below the cookie are counted.
This can be set to nil on a per-node basis using a COOKIE_DATA property
with the word \"recursive\" in the value."
  :group 'org-plain-lists
  :type 'boolean)

(defcustom org-list-indent-offset 0
  "Additional indentation for sub-items in a list.
By setting this to a small number, usually 1 or 2, one can more
clearly distinguish sub-items in a list."
  :group 'org-plain-lists
  :version "24.1"
  :type 'integer)

(defvar org-list-forbidden-blocks '("example" "verse" "src" "export")
  "Names of blocks where lists are not allowed.
Names must be in lower case.")

\f
;;; Predicates and regexps

(defconst org-list-end-re "^[ \t]*\n[ \t]*\n"
  "Regex matching the end of a plain list.")

(defconst org-list-full-item-re
  (concat "^[ \t]*\\(\\(?:[-+*]\\|\\(?:[0-9]+\\|[A-Za-z]\\)[.)]\\)\\(?:[ \t]+\\|$\\)\\)"
	  "\\(?:\\[@\\(?:start:\\)?\\([0-9]+\\|[A-Za-z]\\)\\][ \t]*\\)?"
	  "\\(?:\\(\\[[ X-]\\]\\)\\(?:[ \t]+\\|$\\)\\)?"
	  "\\(?:\\(.*\\)[ \t]+::\\(?:[ \t]+\\|$\\)\\)?")
  "Matches a list item and puts everything into groups:
group 1: bullet
group 2: counter
group 3: checkbox
group 4: description tag")

(defun org-item-re ()
  "Return the correct regular expression for plain lists."
  (let ((term (cond
	       ((eq org-plain-list-ordered-item-terminator t) "[.)]")
	       ((= org-plain-list-ordered-item-terminator ?\)) ")")
	       ((= org-plain-list-ordered-item-terminator ?.) "\\.")
	       (t "[.)]")))
	(alpha (if org-list-allow-alphabetical "\\|[A-Za-z]" "")))
    (concat "\\([ \t]*\\([-+]\\|\\(\\([0-9]+" alpha "\\)" term
	    "\\)\\)\\|[ \t]+\\*\\)\\([ \t]+\\|$\\)")))

(defsubst org-item-beginning-re ()
  "Regexp matching the beginning of a plain list item."
  (concat "^" (org-item-re)))

(defun org-list-at-regexp-after-bullet-p (regexp)
  "Is point at a list item with REGEXP after bullet?"
  (and (org-at-item-p)
       (save-excursion
	 (goto-char (match-end 0))
	 (let ((counter-re (concat "\\(?:\\[@\\(?:start:\\)?"
				   (if org-list-allow-alphabetical
				       "\\([0-9]+\\|[A-Za-z]\\)"
				     "[0-9]+")
				   "\\][ \t]*\\)")))
	   ;; Ignore counter if any
	   (when (looking-at counter-re) (goto-char (match-end 0))))
	 (looking-at regexp))))

(defun org-list-in-valid-context-p ()
  "Is point in a context where lists are allowed?"
  (not (org-in-block-p org-list-forbidden-blocks)))

(defun org-in-item-p ()
  "Return item beginning position when in a plain list, nil otherwise."
  (save-excursion
    (beginning-of-line)
    (let* ((case-fold-search t)
	   (context (org-list-context))
	   (lim-up (car context))
	   (inlinetask-re (and (featurep 'org-inlinetask)
			       (org-inlinetask-outline-regexp)))
	   (item-re (org-item-re))
	   ;; Indentation isn't meaningful when point starts at an empty
	   ;; line or an inline task.
	   (ind-ref (if (or (looking-at "^[ \t]*$")
			    (and inlinetask-re (looking-at inlinetask-re)))
			10000
		      (current-indentation))))
      (cond
       ((eq (nth 2 context) 'invalid) nil)
       ((looking-at item-re) (point))
       (t
	;; Detect if cursor in amidst `org-list-end-re'.  First, count
	;; number HL of hard lines it takes, then call `org-in-regexp'
	;; to compute its boundaries END-BOUNDS.  When point is
	;; in-between, move cursor before regexp beginning.
	(let ((hl 0) (i -1) end-bounds)
	  (when (and (progn
		       (while (setq i (string-match
				       "[\r\n]" org-list-end-re (1+ i)))
			 (setq hl (1+ hl)))
		       (setq end-bounds (org-in-regexp org-list-end-re hl)))
		     (>= (point) (car end-bounds))
		     (< (point) (cdr end-bounds)))
	    (goto-char (car end-bounds))
	    (forward-line -1)))
	;; Look for an item, less indented that reference line.
	(catch 'exit
	  (while t
	    (let ((ind (current-indentation)))
	      (cond
	       ;; This is exactly what we want.
	       ((and (looking-at item-re) (< ind ind-ref))
		(throw 'exit (point)))
	       ;; At upper bound of search or looking at the end of a
	       ;; previous list: search is over.
	       ((<= (point) lim-up) (throw 'exit nil))
	       ((looking-at org-list-end-re) (throw 'exit nil))
	       ;; Skip blocks, drawers, inline-tasks, blank lines
	       ((and (looking-at "^[ \t]*#\\+end_")
		     (re-search-backward "^[ \t]*#\\+begin_" lim-up t)))
	       ((and (looking-at "^[ \t]*:END:")
		     (re-search-backward org-drawer-regexp lim-up t))
		(beginning-of-line))
	       ((and inlinetask-re (looking-at inlinetask-re))
		(org-inlinetask-goto-beginning)
		(forward-line -1))
	       ((looking-at "^[ \t]*$") (forward-line -1))
	       ;; Text at column 0 cannot belong to a list: stop.
	       ((zerop ind) (throw 'exit nil))
	       ;; Normal text less indented than reference line, take
	       ;; it as new reference.
	       ((< ind ind-ref)
		(setq ind-ref ind)
		(forward-line -1))
	       (t (forward-line -1)))))))))))

(defun org-at-item-p ()
  "Is point in a line starting a hand-formatted item?"
  (save-excursion
    (beginning-of-line)
    (and (looking-at (org-item-re)) (org-list-in-valid-context-p))))

(defun org-at-item-bullet-p ()
  "Is point at the bullet of a plain list item?"
  (and (org-at-item-p)
       (not (member (char-after) '(?\  ?\t)))
       (< (point) (match-end 0))))

(defun org-at-item-timer-p ()
  "Is point at a line starting a plain list item with a timer?"
  (org-list-at-regexp-after-bullet-p
   "\\([0-9]+:[0-9]+:[0-9]+\\)[ \t]+::[ \t]+"))

(defun org-at-item-description-p ()
  "Is point at a description list item?"
  (org-list-at-regexp-after-bullet-p "\\(\\S-.+\\)[ \t]+::\\([ \t]+\\|$\\)"))

(defun org-at-item-checkbox-p ()
  "Is point at a line starting a plain-list item with a checklet?"
  (org-list-at-regexp-after-bullet-p "\\(\\[[- X]\\]\\)[ \t]+"))

(defun org-at-item-counter-p ()
  "Is point at a line starting a plain-list item with a counter?"
  (and (org-at-item-p)
       (looking-at org-list-full-item-re)
       (match-string 2)))


\f
;;; Structures and helper functions

(defun org-list-context ()
  "Determine context, and its boundaries, around point.

Context will be a cell like (MIN MAX CONTEXT) where MIN and MAX
are boundaries and CONTEXT is a symbol among `drawer', `block',
`invalid', `inlinetask' and nil.

Contexts `block' and `invalid' refer to `org-list-forbidden-blocks'."
  (save-match-data
    (save-excursion
      (org-with-limited-levels
       (beginning-of-line)
       (let ((case-fold-search t) (pos (point)) beg end context-type
	     ;; Get positions of surrounding headings.  This is the
	     ;; default context.
	     (lim-up (or (save-excursion (and (ignore-errors (org-back-to-heading t))
					      (point)))
			 (point-min)))
	     (lim-down (or (save-excursion (outline-next-heading)) (point-max))))
	 ;; Is point inside a drawer?
	 (let ((end-re "^[ \t]*:END:")
	       (beg-re org-drawer-regexp))
	   (when (save-excursion
		   (and (not (looking-at beg-re))
			(not (looking-at end-re))
			(setq beg (and (re-search-backward beg-re lim-up t)
				       (1+ (point-at-eol))))
			(setq end (or (and (re-search-forward end-re lim-down t)
					   (1- (match-beginning 0)))
				      lim-down))
			(>= end pos)))
	     (setq lim-up beg lim-down end context-type 'drawer)))
	 ;; Is point strictly in a block, and of which type?
	 (let ((block-re "^[ \t]*#\\+\\(begin\\|end\\)_") type)
	   (when (save-excursion
		   (and (not (looking-at block-re))
			(setq beg (and (re-search-backward block-re lim-up t)
				       (1+ (point-at-eol))))
			(looking-at "^[ \t]*#\\+begin_\\(\\S-+\\)")
			(setq type (downcase (match-string 1)))
			(goto-char beg)
			(setq end (or (and (re-search-forward block-re lim-down t)
					   (1- (point-at-bol)))
				      lim-down))
			(>= end pos)
			(equal (downcase (match-string 1)) "end")))
	     (setq lim-up beg lim-down end
		   context-type (if (member type org-list-forbidden-blocks)
				    'invalid 'block))))
	 ;; Is point in an inlinetask?
	 (when (and (featurep 'org-inlinetask)
		    (save-excursion
		      (let* ((beg-re (org-inlinetask-outline-regexp))
			     (end-re (concat beg-re "END[ \t]*$")))
			(and (not (looking-at "^\\*+"))
			     (setq beg (and (re-search-backward beg-re lim-up t)
					    (1+ (point-at-eol))))
			     (not (looking-at end-re))
			     (setq end (and (re-search-forward end-re lim-down t)
					    (1- (match-beginning 0))))
			     (> (point) pos)))))
	   (setq lim-up beg lim-down end context-type 'inlinetask))
	 ;; Return context boundaries and type.
	 (list lim-up lim-down context-type))))))

(defun org-list-struct ()
  "Return structure of list at point.

A list structure is an alist where key is point at item, and
values are:
1. indentation,
2. bullet with trailing whitespace,
3. bullet counter, if any,
4. checkbox, if any,
5. description tag, if any,
6. position at item end.

Thus the following list, where numbers in parens are
point-at-bol:

- [X] first item                             (1)
  1. sub-item 1                              (18)
  5. [@5] sub-item 2                         (34)
  some other text belonging to first item    (55)
- last item                                  (97)
  + tag :: description                       (109)
                                             (131)

will get the following structure:

 ((1 0 \"- \"  nil \"[X]\" nil 97)
  (18 2 \"1. \"  nil nil nil 34)
  (34 2 \"5. \" \"5\" nil nil 55)
  (97 0 \"- \"  nil nil nil 131)
  (109 2 \"+ \" nil nil \"tag\" 131))

Assume point is at an item."
  (save-excursion
    (beginning-of-line)
    (let* ((case-fold-search t)
	   (context (org-list-context))
	   (lim-up (car context))
	   (lim-down (nth 1 context))
	   (text-min-ind 10000)
	   (item-re (org-item-re))
	   (inlinetask-re (and (featurep 'org-inlinetask)
			       (org-inlinetask-outline-regexp)))
	   (beg-cell (cons (point) (current-indentation)))
           itm-lst itm-lst-2 end-lst end-lst-2 struct
	   (assoc-at-point
	    ;; Return association at point.
	    (lambda (ind)
	      (looking-at org-list-full-item-re)
	      (let ((bullet (match-string-no-properties 1)))
		(list (point)
		      ind
		      bullet
		      (match-string-no-properties 2) ; counter
		      (match-string-no-properties 3) ; checkbox
		      ;; Description tag.
		      (and (string-match-p "[-+*]" bullet)
			   (match-string-no-properties 4))))))
	   (end-before-blank
	    ;; Ensure list ends at the first blank line.
	    (lambda ()
	      (skip-chars-backward " \r\t\n")
	      (min (1+ (point-at-eol)) lim-down))))
      ;; 1. Read list from starting item to its beginning, and save
      ;;    top item position and indentation in BEG-CELL.  Also store
      ;;    ending position of items in END-LST.
      (save-excursion
	(catch 'exit
	  (while t
	    (let ((ind (current-indentation)))
	      (cond
	       ((<= (point) lim-up)
		;; At upward limit: if we ended at an item, store it,
		;; else dismiss useless data recorded above BEG-CELL.
		;; Jump to part 2.
		(throw 'exit
		       (setq itm-lst
			     (if (not (looking-at item-re))
				 (memq (assq (car beg-cell) itm-lst) itm-lst)
			       (setq beg-cell (cons (point) ind))
			       (cons (funcall assoc-at-point ind) itm-lst)))))
	       ;; Looking at a list ending regexp.  Dismiss useless
	       ;; data recorded above BEG-CELL.  Jump to part 2.
	       ((looking-at org-list-end-re)
		(throw 'exit
		       (setq itm-lst
			     (memq (assq (car beg-cell) itm-lst) itm-lst))))
	       ;; Point is at an item.  Add data to ITM-LST. It may
	       ;; also end a previous item: save it in END-LST.  If
	       ;; ind is less or equal than BEG-CELL and there is no
	       ;; end at this ind or lesser, this item becomes the new
	       ;; BEG-CELL.
	       ((looking-at item-re)
		(push (funcall assoc-at-point ind) itm-lst)
		(push (cons ind (point)) end-lst)
		(when (< ind text-min-ind) (setq beg-cell (cons (point) ind)))
		(forward-line -1))
	       ;; Skip blocks, drawers, inline tasks, blank lines.
	       ((and (looking-at "^[ \t]*#\\+end_")
		     (re-search-backward "^[ \t]*#\\+begin_" lim-up t)))
	       ((and (looking-at "^[ \t]*:END:")
		     (re-search-backward org-drawer-regexp lim-up t))
		(beginning-of-line))
	       ((and inlinetask-re (looking-at inlinetask-re))
		(org-inlinetask-goto-beginning)
		(forward-line -1))
	       ((looking-at "^[ \t]*$")
		(forward-line -1))
	       ;; From there, point is not at an item.  Interpret
	       ;; line's indentation:
	       ;; - text at column 0 is necessarily out of any list.
	       ;;   Dismiss data recorded above BEG-CELL.  Jump to
	       ;;   part 2.
	       ;; - any other case may be an ending position for an
	       ;;   hypothetical item above.  Store it and proceed.
	       ((zerop ind)
		(throw 'exit
		       (setq itm-lst
			     (memq (assq (car beg-cell) itm-lst) itm-lst))))
	       (t
		(when (< ind text-min-ind) (setq text-min-ind ind))
		(push (cons ind (point)) end-lst)
		(forward-line -1)))))))
      ;; 2. Read list from starting point to its end, that is until we
      ;;    get out of context, or that a non-item line is less or
      ;;    equally indented than BEG-CELL's cdr.  Also, store ending
      ;;    position of items in END-LST-2.
      (catch 'exit
	(while t
	  (let ((ind (current-indentation)))
	    (cond
	     ((>= (point) lim-down)
	      ;; At downward limit: this is de facto the end of the
	      ;; list.  Save point as an ending position, and jump to
	      ;; part 3.
	      (throw 'exit
		     (push (cons 0 (funcall end-before-blank)) end-lst-2)))
	     ;; Looking at a list ending regexp.  Save point as an
	     ;; ending position and jump to part 3.
	     ((looking-at org-list-end-re)
	      (throw 'exit (push (cons 0 (point)) end-lst-2)))
	     ((looking-at item-re)
	      ;; Point is at an item.  Add data to ITM-LST-2. It may
	      ;; also end a previous item, so save it in END-LST-2.
	      (push (funcall assoc-at-point ind) itm-lst-2)
	      (push (cons ind (point)) end-lst-2)
	      (forward-line 1))
	     ;; Skip inline tasks and blank lines along the way
	     ((and inlinetask-re (looking-at inlinetask-re))
	      (org-inlinetask-goto-end))
	     ((looking-at "^[ \t]*$")
	      (forward-line 1))
	     ;; Ind is lesser or equal than BEG-CELL's.  The list is
	     ;; over: store point as an ending position and jump to
	     ;; part 3.
	     ((<= ind (cdr beg-cell))
	      (throw 'exit
		     (push (cons 0 (funcall end-before-blank)) end-lst-2)))
	     ;; Else, if ind is lesser or equal than previous item's,
	     ;; this is an ending position: store it.  In any case,
	     ;; skip block or drawer at point, and move to next line.
	     (t
	      (when (<= ind (nth 1 (car itm-lst-2)))
		(push (cons ind (point)) end-lst-2))
	      (cond
	       ((and (looking-at "^[ \t]*#\\+begin_")
		     (re-search-forward "^[ \t]*#\\+end_" lim-down t)))
	       ((and (looking-at org-drawer-regexp)
		     (re-search-forward "^[ \t]*:END:" lim-down t))))
	      (forward-line 1))))))
      (setq struct (append itm-lst (cdr (nreverse itm-lst-2)))
	    end-lst (append end-lst (cdr (nreverse end-lst-2))))
      ;; 3. Associate each item to its end position.
      (org-list-struct-assoc-end struct end-lst)
      ;; 4. Return STRUCT
      struct)))

(defun org-list-struct-assoc-end (struct end-list)
  "Associate proper ending point to items in STRUCT.

END-LIST is a pseudo-alist where car is indentation and cdr is
ending position.

This function modifies STRUCT."
  (let ((endings end-list))
    (mapc
     (lambda (elt)
       (let ((pos (car elt))
	     (ind (nth 1 elt)))
	 ;; Remove end candidates behind current item.
	 (while (or (<= (cdar endings) pos))
	   (pop endings))
	 ;; Add end position to item assoc.
	 (let ((old-end (nthcdr 6 elt))
	       (new-end (assoc-default ind endings '<=)))
	   (if old-end
	       (setcar old-end new-end)
	     (setcdr elt (append (cdr elt) (list new-end)))))))
     struct)))

(defun org-list-prevs-alist (struct)
  "Return alist between item and previous item in STRUCT."
  (let ((item-end-alist (mapcar (lambda (e) (cons (car e) (nth 6 e)))
				struct)))
    (mapcar (lambda (e)
	      (let ((prev (car (rassq (car e) item-end-alist))))
		(cons (car e) prev)))
	    struct)))

(defun org-list-parents-alist (struct)
  "Return alist between item and parent in STRUCT."
  (let* ((ind-to-ori (list (list (nth 1 (car struct)))))
	 (top-item (org-list-get-top-point struct))
	 (prev-pos (list top-item)))
    (cons prev-pos
	  (mapcar (lambda (item)
		    (let ((pos (car item))
			  (ind (nth 1 item))
			  (prev-ind (caar ind-to-ori)))
		      (push pos prev-pos)
		      (cond
		       ((> prev-ind ind)
			;; A sub-list is over.  Find the associated
			;; origin in IND-TO-ORI.  If it cannot be
			;; found (ill-formed list), set its parent as
			;; the first item less indented.  If there is
			;; none, make it a top-level item.
			(setq ind-to-ori
			      (or (member (assq ind ind-to-ori) ind-to-ori)
                                  (catch 'exit
                                    (mapc
                                     (lambda (e)
                                       (when (< (car e) ind)
                                         (throw 'exit (member e ind-to-ori))))
                                     ind-to-ori)
                                    (list (list ind)))))
			(cons pos (cdar ind-to-ori)))
                       ;; A sub-list starts.  Every item at IND will
                       ;; have previous item as its parent.
		       ((< prev-ind ind)
			(let ((origin (nth 1 prev-pos)))
			  (push (cons ind origin) ind-to-ori)
			  (cons pos origin)))
                       ;; Another item in the same sub-list: it shares
                       ;; the same parent as the previous item.
		       (t (cons pos (cdar ind-to-ori))))))
		  (cdr struct)))))

(defun org-list--delete-metadata ()
  "Delete metadata from the heading at point.
Metadata are tags, planning information and properties drawers."
  (save-match-data
    (org-with-wide-buffer
     (org-set-tags nil)
     (delete-region (line-beginning-position 2)
		    (save-excursion
		      (org-end-of-meta-data)
		      (org-skip-whitespace)
		      (if (eobp) (point) (line-beginning-position)))))))

\f
;;; Accessors

(defsubst org-list-get-nth (n key struct)
  "Return the Nth value of KEY in STRUCT."
  (nth n (assq key struct)))

(defun org-list-set-nth (n key struct new)
  "Set the Nth value of KEY in STRUCT to NEW.
\nThis function modifies STRUCT."
  (setcar (nthcdr n (assq key struct)) new))

(defsubst org-list-get-ind (item struct)
  "Return indentation of ITEM in STRUCT."
  (org-list-get-nth 1 item struct))

(defun org-list-set-ind (item struct ind)
  "Set indentation of ITEM in STRUCT to IND.
\nThis function modifies STRUCT."
  (org-list-set-nth 1 item struct ind))

(defsubst org-list-get-bullet (item struct)
  "Return bullet of ITEM in STRUCT."
  (org-list-get-nth 2 item struct))

(defun org-list-set-bullet (item struct bullet)
  "Set bullet of ITEM in STRUCT to BULLET.
\nThis function modifies STRUCT."
  (org-list-set-nth 2 item struct bullet))

(defsubst org-list-get-counter (item struct)
  "Return counter of ITEM in STRUCT."
  (org-list-get-nth 3 item struct))

(defsubst org-list-get-checkbox (item struct)
  "Return checkbox of ITEM in STRUCT or nil."
  (org-list-get-nth 4 item struct))

(defun org-list-set-checkbox (item struct checkbox)
  "Set checkbox of ITEM in STRUCT to CHECKBOX.
\nThis function modifies STRUCT."
  (org-list-set-nth 4 item struct checkbox))

(defsubst org-list-get-tag (item struct)
  "Return end position of ITEM in STRUCT."
  (org-list-get-nth 5 item struct))

(defun org-list-get-item-end (item struct)
  "Return end position of ITEM in STRUCT."
  (org-list-get-nth 6 item struct))

(defun org-list-get-item-end-before-blank (item struct)
  "Return point at end of ITEM in STRUCT, before any blank line.
Point returned is at end of line."
  (save-excursion
    (goto-char (org-list-get-item-end item struct))
    (skip-chars-backward " \r\t\n")
    (point-at-eol)))

(defun org-list-get-parent (item struct parents)
  "Return parent of ITEM or nil.
STRUCT is the list structure.  PARENTS is the alist of parents,
as returned by `org-list-parents-alist'."
  (let ((parents (or parents (org-list-parents-alist struct))))
    (cdr (assq item parents))))

(defun org-list-has-child-p (item struct)
  "Non-nil if ITEM has a child.

STRUCT is the list structure.

Value returned is the position of the first child of ITEM."
  (let ((ind (org-list-get-ind item struct))
	(child-maybe (car (nth 1 (member (assq item struct) struct)))))
    (when (and child-maybe
	       (< ind (org-list-get-ind child-maybe struct)))
      child-maybe)))

(defun org-list-get-next-item (item _struct prevs)
  "Return next item in same sub-list as ITEM, or nil.
STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'."
  (car (rassq item prevs)))

(defun org-list-get-prev-item (item _struct prevs)
  "Return previous item in same sub-list as ITEM, or nil.
STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'."
  (cdr (assq item prevs)))

(defun org-list-get-subtree (item struct)
  "List all items having ITEM as a common ancestor, or nil.
STRUCT is the list structure."
  (let* ((item-end (org-list-get-item-end item struct))
	 (sub-struct (cdr (member (assq item struct) struct)))
	 items)
    (catch :exit
      (pcase-dolist (`(,pos . ,_) sub-struct)
	(if (< pos item-end)
	    (push pos items)
	  (throw :exit nil))))
    (nreverse items)))

(defun org-list-get-all-items (item struct prevs)
  "List all items in the same sub-list as ITEM.
STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'."
  (let ((prev-item item)
	(next-item item)
	before-item after-item)
    (while (setq prev-item (org-list-get-prev-item prev-item struct prevs))
      (push prev-item before-item))
    (while (setq next-item (org-list-get-next-item next-item struct prevs))
      (push next-item after-item))
    (append before-item (list item) (nreverse after-item))))

(defun org-list-get-children (item _struct parents)
  "List all children of ITEM, or nil.
STRUCT is the list structure.  PARENTS is the alist of parents,
as returned by `org-list-parents-alist'."
  (let (all child)
    (while (setq child (car (rassq item parents)))
      (setq parents (cdr (member (assq child parents) parents)))
      (push child all))
    (nreverse all)))

(defun org-list-get-top-point (struct)
  "Return point at beginning of list.
STRUCT is the list structure."
  (caar struct))

(defun org-list-get-bottom-point (struct)
  "Return point at bottom of list.
STRUCT is the list structure."
  (apply #'max
	 (mapcar (lambda (e) (org-list-get-item-end (car e) struct)) struct)))

(defun org-list-get-list-begin (item struct prevs)
  "Return point at beginning of sub-list ITEM belongs.
STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'."
  (let ((first-item item) prev-item)
    (while (setq prev-item (org-list-get-prev-item first-item struct prevs))
      (setq first-item prev-item))
    first-item))

(defalias 'org-list-get-first-item 'org-list-get-list-begin)

(defun org-list-get-last-item (item struct prevs)
  "Return point at last item of sub-list ITEM belongs.
STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'."
  (let ((last-item item) next-item)
    (while (setq next-item (org-list-get-next-item last-item struct prevs))
      (setq last-item next-item))
    last-item))

(defun org-list-get-list-end (item struct prevs)
  "Return point at end of sub-list ITEM belongs.
STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'."
  (org-list-get-item-end (org-list-get-last-item item struct prevs) struct))

(defun org-list-get-list-type (item struct prevs)
  "Return the type of the list containing ITEM, as a symbol.

STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'.

Possible types are `descriptive', `ordered' and `unordered'.  The
type is determined by the first item of the list."
  (let ((first (org-list-get-list-begin item struct prevs)))
    (cond
     ((string-match-p "[[:alnum:]]" (org-list-get-bullet first struct)) 'ordered)
     ((org-list-get-tag first struct) 'descriptive)
     (t 'unordered))))

(defun org-list-get-item-number (item struct prevs parents)
  "Return ITEM's sequence number.

STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'.  PARENTS is the
alist of ancestors, as returned by `org-list-parents-alist'.

Return value is a list of integers.  Counters have an impact on
that value."
  (let ((get-relative-number
	 (lambda (item struct prevs)
	   ;; Return relative sequence number of ITEM in the sub-list
	   ;; it belongs.  STRUCT is the list structure.  PREVS is
	   ;; the alist of previous items.
	   (let ((seq 0) (pos item) counter)
	     (while (and (not (setq counter (org-list-get-counter pos struct)))
			 (setq pos (org-list-get-prev-item pos struct prevs)))
	       (cl-incf seq))
	     (if (not counter) (1+ seq)
	       (cond
		((string-match "[A-Za-z]" counter)
		 (+ (- (string-to-char (upcase (match-string 0 counter))) 64)
		    seq))
		((string-match "[0-9]+" counter)
		 (+ (string-to-number (match-string 0 counter)) seq))
		(t (1+ seq))))))))
    ;; Cons each parent relative number into return value (OUT).
    (let ((out (list (funcall get-relative-number item struct prevs)))
	  (parent item))
      (while (setq parent (org-list-get-parent parent struct parents))
	(push (funcall get-relative-number parent struct prevs) out))
      ;; Return value.
      out)))


\f
;;; Searching

(defun org-list-search-generic (search re bound noerr)
  "Search a string in valid contexts for lists.
Arguments SEARCH, RE, BOUND and NOERR are similar to those used
in `re-search-forward'."
  (catch 'exit
    (let ((origin (point)))
      (while t
	;; 1. No match: return to origin or bound, depending on NOERR.
	(unless (funcall search re bound noerr)
	  (throw 'exit (and (goto-char (if (memq noerr '(t nil)) origin bound))
			    nil)))
	;; 2. Match in valid context: return point.  Else, continue
	;;    searching.
	(when (org-list-in-valid-context-p) (throw 'exit (point)))))))

(defun org-list-search-backward (regexp &optional bound noerror)
  "Like `re-search-backward' but stop only where lists are recognized.
Arguments REGEXP, BOUND and NOERROR are similar to those used in
`re-search-backward'."
  (org-list-search-generic #'re-search-backward
			   regexp (or bound (point-min)) noerror))

(defun org-list-search-forward (regexp &optional bound noerror)
  "Like `re-search-forward' but stop only where lists are recognized.
Arguments REGEXP, BOUND and NOERROR are similar to those used in
`re-search-forward'."
  (org-list-search-generic #'re-search-forward
			   regexp (or bound (point-max)) noerror))


\f
;;; Methods on structures

(defsubst org-list-bullet-string (bullet)
  "Return BULLET with the correct number of whitespaces.
It determines the number of whitespaces to append by looking at
`org-list-two-spaces-after-bullet-regexp'."
  (save-match-data
    (let ((spaces (if (and org-list-two-spaces-after-bullet-regexp
			   (string-match
			    org-list-two-spaces-after-bullet-regexp bullet))
		      "  "
		    " ")))
      (if (string-match "\\S-+\\([ \t]*\\)" bullet)
	  (replace-match spaces nil nil bullet 1)
	bullet))))

(defun org-list-swap-items (beg-A beg-B struct)
  "Swap item starting at BEG-A with item starting at BEG-B in STRUCT.

Blank lines at the end of items are left in place.  Item
visibility is preserved.  Return the new structure after the
changes.

Assume BEG-A is lesser than BEG-B and that BEG-A and BEG-B belong
to the same sub-list.

This function modifies STRUCT."
  (save-excursion
    (let* ((end-A-no-blank (org-list-get-item-end-before-blank beg-A struct))
	   (end-B-no-blank (org-list-get-item-end-before-blank beg-B struct))
	   (end-A (org-list-get-item-end beg-A struct))
	   (end-B (org-list-get-item-end beg-B struct))
	   (size-A (- end-A-no-blank beg-A))
	   (size-B (- end-B-no-blank beg-B))
	   (body-A (buffer-substring beg-A end-A-no-blank))
	   (body-B (buffer-substring beg-B end-B-no-blank))
	   (between-A-no-blank-and-B (buffer-substring end-A-no-blank beg-B))
	   (sub-A (cons beg-A (org-list-get-subtree beg-A struct)))
	   (sub-B (cons beg-B (org-list-get-subtree beg-B struct)))
	   ;; Store overlays responsible for visibility status.  We
	   ;; also need to store their boundaries as they will be
	   ;; removed from buffer.
	   (overlays
	    (cons
	     (delq nil
		   (mapcar (lambda (o)
			     (and (>= (overlay-start o) beg-A)
				  (<= (overlay-end o) end-A)
				  (list o (overlay-start o) (overlay-end o))))
			   (overlays-in beg-A end-A)))
	     (delq nil
		   (mapcar (lambda (o)
			     (and (>= (overlay-start o) beg-B)
				  (<= (overlay-end o) end-B)
				  (list o (overlay-start o) (overlay-end o))))
			   (overlays-in beg-B end-B))))))
      ;; 1. Move effectively items in buffer.
      (goto-char beg-A)
      (delete-region beg-A end-B-no-blank)
      (insert (concat body-B between-A-no-blank-and-B body-A))
      ;; 2. Now modify struct.  No need to re-read the list, the
      ;;    transformation is just a shift of positions.  Some special
      ;;    attention is required for items ending at END-A and END-B
      ;;    as empty spaces are not moved there.  In others words,
      ;;    item BEG-A will end with whitespaces that were at the end
      ;;    of BEG-B and the same applies to BEG-B.
      (dolist (e struct)
	(let ((pos (car e)))
	  (cond
	   ((< pos beg-A))
	   ((memq pos sub-A)
	    (let ((end-e (nth 6 e)))
	      (setcar e (+ pos (- end-B-no-blank end-A-no-blank)))
	      (setcar (nthcdr 6 e)
		      (+ end-e (- end-B-no-blank end-A-no-blank)))
	      (when (= end-e end-A) (setcar (nthcdr 6 e) end-B))))
	   ((memq pos sub-B)
	    (let ((end-e (nth 6 e)))
	      (setcar e (- (+ pos beg-A) beg-B))
	      (setcar (nthcdr 6 e) (+ end-e (- beg-A beg-B)))
	      (when (= end-e end-B)
		(setcar (nthcdr 6 e)
			(+ beg-A size-B (- end-A end-A-no-blank))))))
	   ((< pos beg-B)
	    (let ((end-e (nth 6 e)))
	      (setcar e (+ pos (- size-B size-A)))
	      (setcar (nthcdr 6 e) (+ end-e (- size-B size-A))))))))
      (setq struct (sort struct #'car-less-than-car))
      ;; Restore visibility status, by moving overlays to their new
      ;; position.
      (dolist (ov (car overlays))
	(move-overlay
	 (car ov)
	 (+ (nth 1 ov) (- (+ beg-B (- size-B size-A)) beg-A))
	 (+ (nth 2 ov) (- (+ beg-B (- size-B size-A)) beg-A))))
      (dolist (ov (cdr overlays))
	(move-overlay (car ov)
		      (+ (nth 1 ov) (- beg-A beg-B))
		      (+ (nth 2 ov) (- beg-A beg-B))))
      ;; Return structure.
      struct)))

(defun org-list-separating-blank-lines-number (pos struct prevs)
  "Return number of blank lines that should separate items in list.

POS is the position of point where `org-list-insert-item' was called.

STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'.

Assume point is at item's beginning.  If the item is alone, apply
some heuristics to guess the result."
  (save-excursion
    (let ((item (point))
	  (insert-blank-p
	   (cdr (assq 'plain-list-item org-blank-before-new-entry)))
	  usr-blank
	  (count-blanks
	   (lambda ()
	     ;; Count blank lines above beginning of line.
	     (save-excursion
	       (count-lines (goto-char (point-at-bol))
			    (progn (skip-chars-backward " \r\t\n")
				   (forward-line)
				   (point)))))))
      (cond
       ;; Trivial cases where there should be none.
       ((not insert-blank-p) 0)
       ;; When `org-blank-before-new-entry' says so, it is 1.
       ((eq insert-blank-p t) 1)
       ;; `plain-list-item' is 'auto.  Count blank lines separating
       ;; neighbors' items in list.
       (t (let ((next-p (org-list-get-next-item item struct prevs)))
	    (cond
	     ;; Is there a next item?
	     (next-p (goto-char next-p)
		     (funcall count-blanks))
	     ;; Is there a previous item?
	     ((org-list-get-prev-item item struct prevs)
	      (funcall count-blanks))
	     ;; User inserted blank lines, trust him.
	     ((and (> pos (org-list-get-item-end-before-blank item struct))
		   (> (save-excursion (goto-char pos)
				      (setq usr-blank (funcall count-blanks)))
		      0))
	      usr-blank)
	     ;; Are there blank lines inside the list so far?
	     ((save-excursion
		(goto-char (org-list-get-top-point struct))
		;; Do not use `org-list-search-forward' so blank lines
		;; in blocks can be counted in.
		(re-search-forward
		 "^[ \t]*$" (org-list-get-item-end-before-blank item struct) t))
	      1)
	     ;; Default choice: no blank line.
	     (t 0))))))))

(defun org-list-insert-item (pos struct prevs &optional checkbox after-bullet)
  "Insert a new list item at POS and return the new structure.
If POS is before first character after bullet of the item, the
new item will be created before the current one.

STRUCT is the list structure.  PREVS is the alist of previous
items, as returned by `org-list-prevs-alist'.

Insert a checkbox if CHECKBOX is non-nil, and string AFTER-BULLET
after the bullet.  Cursor will be after this text once the
function ends.

This function modifies STRUCT."
  (let* ((case-fold-search t)
	 ;; Get information about list: ITEM containing POS, position
	 ;; of point with regards to item start (BEFOREP), blank lines
	 ;; number separating items (BLANK-NB), if we're allowed to
	 ;; (SPLIT-LINE-P).
	 (item
	  (catch :exit
	    (let ((i nil))
	      (pcase-dolist (`(,start ,_ ,_ ,_ ,_ ,_ ,end) struct)
		(cond
		 ((> start pos) (throw :exit i))
		 ((< end pos) nil)	;skip sub-lists before point
		 (t (setq i start))))
	      ;; If no suitable item is found, insert a sibling of the
	      ;; last item in buffer.
	      (or i (caar (reverse struct))))))
	 (item-end (org-list-get-item-end item struct))
	 (item-end-no-blank (org-list-get-item-end-before-blank item struct))
	 (beforep
	  (progn
	    (goto-char item)
	    (looking-at org-list-full-item-re)
	    (<= pos
		(cond
		 ((not (match-beginning 4)) (match-end 0))
		 ;; Ignore tag in a non-descriptive list.
		 ((save-match-data (string-match "[.)]" (match-string 1)))
		  (match-beginning 4))
		 (t (save-excursion
		      (goto-char (match-end 4))
		      (skip-chars-forward " \t")
		      (point)))))))
	 (split-line-p (org-get-alist-option org-M-RET-may-split-line 'item))
	 (blank-nb (org-list-separating-blank-lines-number pos struct prevs))
	 ;; Build the new item to be created.  Concatenate same bullet
	 ;; as item, checkbox, text AFTER-BULLET if provided, and text
	 ;; cut from point to end of item (TEXT-CUT) to form item's
	 ;; BODY.  TEXT-CUT depends on BEFOREP and SPLIT-LINE-P.  The
	 ;; difference of size between what was cut and what was
	 ;; inserted in buffer is stored in SIZE-OFFSET.
	 (ind (org-list-get-ind item struct))
	 (ind-size (if indent-tabs-mode
		       (+ (/ ind tab-width) (mod ind tab-width))
		     ind))
	 (bullet (org-list-bullet-string (org-list-get-bullet item struct)))
	 (box (and checkbox "[ ]"))
	 (text-cut
	  (and (not beforep)
	       split-line-p
	       (progn
		 (goto-char pos)
		 ;; If POS is greater than ITEM-END, then point is in
		 ;; some white lines after the end of the list.  Those
		 ;; must be removed, or they will be left, stacking up
		 ;; after the list.
		 (when (< item-end pos)
		   (delete-region (1- item-end) (point-at-eol)))
		 (skip-chars-backward " \r\t\n")
		 ;; Cut position is after any blank on the line.
		 (save-excursion
		   (skip-chars-forward " \t")
		   (setq pos (point)))
		 (delete-and-extract-region (point) item-end-no-blank))))
	 (body
	  (concat bullet
		  (and box (concat box " "))
		  after-bullet
		  (and text-cut
		       (if (string-match "\\`[ \t]+" text-cut)
			   (replace-match "" t t text-cut)
			 text-cut))))
	 (item-sep (make-string  (1+ blank-nb) ?\n))
	 (item-size (+ ind-size (length body) (length item-sep)))
	 (size-offset (- item-size (length text-cut))))
    ;; Insert effectively item into buffer.
    (goto-char item)
    (indent-to-column ind)
    (insert body item-sep)
    ;; Add new item to STRUCT.
    (dolist (e struct)
      (let ((p (car e)) (end (nth 6 e)))
	(cond
	 ;; Before inserted item, positions don't change but an item
	 ;; ending after insertion has its end shifted by SIZE-OFFSET.
	 ((< p item)
	  (when (> end item)
	    (setcar (nthcdr 6 e) (+ end size-offset))))
	 ;; Item where insertion happens may be split in two parts.
	 ;; In this case, move start by ITEM-SIZE and end by
	 ;; SIZE-OFFSET.
	 ((and (= p item) (not beforep) split-line-p)
	  (setcar e (+ p item-size))
	  (setcar (nthcdr 6 e) (+ end size-offset)))
	 ;; Items starting after modified item fall into two
	 ;; categories.
	 ;;
	 ;; If modified item was split, and current sub-item was
	 ;; located after split point, it was moved to the new item:
	 ;; the part between body start and split point (POS) was
	 ;; removed.  So we compute the length of that part and shift
	 ;; item's positions accordingly.
	 ;;
	 ;; Otherwise, the item was simply shifted by SIZE-OFFSET.
	 ((and split-line-p (not beforep) (>= p pos) (<= p item-end-no-blank))
	  (let ((offset (- pos item ind (length bullet) (length after-bullet))))
	    (setcar e (- p offset))
	    (setcar (nthcdr 6 e) (- end offset))))
	 (t
	  (setcar e (+ p size-offset))
	  (setcar (nthcdr 6 e) (+ end size-offset))))))
    (push (list item ind bullet nil box nil (+ item item-size)) struct)
    (setq struct (sort struct #'car-less-than-car))
    ;; If not BEFOREP, new item must appear after ITEM, so exchange
    ;; ITEM with the next item in list.  Position cursor after bullet,
    ;; counter, checkbox, and label.
    (if beforep
	(goto-char item)
      (setq struct (org-list-swap-items item (+ item item-size) struct))
      (goto-char (org-list-get-next-item
		  item struct (org-list-prevs-alist struct))))
    struct))

(defun org-list-delete-item (item struct)
  "Remove ITEM from the list and return the new structure.

STRUCT is the list structure."
  (let* ((end (org-list-get-item-end item struct))
	 (beg (if (= (org-list-get-bottom-point struct) end)
		  ;; If ITEM ends with the list, delete blank lines
		  ;; before it.
		  (save-excursion
		    (goto-char item)
		    (skip-chars-backward " \r\t\n")
		    (min (1+ (point-at-eol)) (point-max)))
		item)))
    ;; Remove item from buffer.
    (delete-region beg end)
    ;; Remove item from structure and shift others items accordingly.
    ;; Don't forget to shift also ending position when appropriate.
    (let ((size (- end beg)))
      (delq nil (mapcar (lambda (e)
			  (let ((pos (car e)))
			    (cond
			     ((< pos item)
			      (let ((end-e (nth 6 e)))
				(cond
				 ((< end-e item) e)
				 ((= end-e item)
				  (append (butlast e) (list beg)))
				 (t
				  (append (butlast e) (list (- end-e size)))))))
			     ((< pos end) nil)
			     (t
			      (cons (- pos size)
				    (append (butlast (cdr e))
					    (list (- (nth 6 e) size))))))))
			struct)))))

(defun org-list-send-item (item dest struct)
  "Send ITEM to destination DEST.

STRUCT is the list structure.

DEST can have various values.

If DEST is a buffer position, the function will assume it points
to another item in the same list as ITEM, and will move the
latter just before the former.

If DEST is `begin' (respectively `end'), ITEM will be moved at
the beginning (respectively end) of the list it belongs to.

If DEST is a string like \"N\", where N is an integer, ITEM will
be moved at the Nth position in the list.

If DEST is `kill', ITEM will be deleted and its body will be
added to the kill-ring.

If DEST is `delete', ITEM will be deleted.

Visibility of item is preserved.

This function returns, destructively, the new list structure."
  (let* ((prevs (org-list-prevs-alist struct))
	 (item-end (org-list-get-item-end item struct))
	 ;; Grab full item body minus its bullet.
	 (body (org-trim
		(buffer-substring
		 (save-excursion
		   (goto-char item)
		   (looking-at
		    (concat "[ \t]*"
			    (regexp-quote (org-list-get-bullet item struct))))
		   (match-end 0))
		 item-end)))
	 ;; Change DEST into a buffer position.  A trick is needed
	 ;; when ITEM is meant to be sent at the end of the list.
	 ;; Indeed, by setting locally `org-M-RET-may-split-line' to
	 ;; nil and insertion point (INS-POINT) to the first line's
	 ;; end of the last item, we ensure the new item will be
	 ;; inserted after the last item, and not after any of its
	 ;; hypothetical sub-items.
	 (ins-point (cond
		     ((or (eq dest 'kill) (eq dest 'delete)))
		     ((eq dest 'begin)
		      (setq dest (org-list-get-list-begin item struct prevs)))
		     ((eq dest 'end)
		      (setq dest (org-list-get-list-end item struct prevs))
		      (save-excursion
			(goto-char (org-list-get-last-item item struct prevs))
			(point-at-eol)))
		     ((string-match-p "\\`[0-9]+\\'" dest)
		      (let* ((all (org-list-get-all-items item struct prevs))
			     (len (length all))
			     (index (mod (string-to-number dest) len)))
			(if (not (zerop index))
			    (setq dest (nth (1- index) all))
			  ;; Send ITEM at the end of the list.
			  (setq dest (org-list-get-list-end item struct prevs))
			  (save-excursion
			    (goto-char
			     (org-list-get-last-item item struct prevs))
			    (point-at-eol)))))
		     (t dest)))
	 (org-M-RET-may-split-line nil)
	 ;; Store inner overlays (to preserve visibility).
	 (overlays (cl-remove-if (lambda (o) (or (< (overlay-start o) item)
						 (> (overlay-end o) item)))
				 (overlays-in item item-end))))
    (cond
     ((eq dest 'delete) (org-list-delete-item item struct))
     ((eq dest 'kill)
      (kill-new body)
      (org-list-delete-item item struct))
     ((and (integerp dest) (/= item ins-point))
      (setq item (copy-marker item))
      (setq struct (org-list-insert-item ins-point struct prevs nil body))
      ;; 1. Structure returned by `org-list-insert-item' may not be
      ;;    accurate, as it cannot see sub-items included in BODY.
      ;;    Thus, first compute the real structure so far.
      (let ((moved-items
	     (cons (marker-position item)
		   (org-list-get-subtree (marker-position item) struct)))
	    (new-end (org-list-get-item-end (point) struct))
	    (old-end (org-list-get-item-end (marker-position item) struct))
	    (new-item (point))
	    (shift (- (point) item)))
	;; 1.1. Remove the item just created in structure.
	(setq struct (delete (assq new-item struct) struct))
	;; 1.2. Copy ITEM and any of its sub-items at NEW-ITEM.
	(setq struct (sort
		      (append
		       struct
		       (mapcar (lambda (e)
				 (let* ((cell (assq e struct))
					(pos (car cell))
					(end (nth 6 cell)))
				   (cons (+ pos shift)
					 (append (butlast (cdr cell))
						 (list (if (= end old-end)
							   new-end
							 (+ end shift)))))))
			       moved-items))
		      #'car-less-than-car)))
      ;; 2. Restore inner overlays.
      (dolist (o overlays)
	(move-overlay o
		      (+ (overlay-start o) (- (point) item))
		      (+ (overlay-end o) (- (point) item))))
      ;; 3. Eventually delete extra copy of the item and clean marker.
      (prog1 (org-list-delete-item (marker-position item) struct)
	(move-marker item nil)))
     (t struct))))

(defun org-list-struct-outdent (start end struct parents)
  "Outdent items between positions START and END.

STRUCT is the list structure.  PARENTS is the alist of items'
parents, as returned by `org-list-parents-alist'.

START is included, END excluded."
  (let* (acc
	 (out (lambda (cell)
		(let* ((item (car cell))
		       (parent (cdr cell)))
		  (cond
		   ;; Item not yet in zone: keep association.
		   ((< item start) cell)
		   ;; Item out of zone: follow associations in ACC.
		   ((>= item end)
		    (let ((convert (and parent (assq parent acc))))
		      (if convert (cons item (cdr convert)) cell)))
		   ;; Item has no parent: error
		   ((not parent)
		    (error "Cannot outdent top-level items"))
		   ;; Parent is outdented: keep association.
		   ((>= parent start)
		    (push (cons parent item) acc) cell)
		   (t
		    ;; Parent isn't outdented: reparent to grand-parent.
		    (let ((grand-parent (org-list-get-parent
					 parent struct parents)))
		      (push (cons parent item) acc)
		      (cons item grand-parent))))))))
    (mapcar out parents)))

(defun org-list-struct-indent (start end struct parents prevs)
  "Indent items between positions START and END.

STRUCT is the list structure.  PARENTS is the alist of parents
and PREVS is the alist of previous items, returned by,
respectively, `org-list-parents-alist' and
`org-list-prevs-alist'.

START is included and END excluded.

STRUCT may be modified if `org-list-demote-modify-bullet' matches
bullets between START and END."
  (let* (acc
	 (set-assoc (lambda (cell) (push cell acc) cell))
	 (ind
	  (lambda (cell)
	    (let* ((item (car cell))
		   (parent (cdr cell)))
	      (cond
	       ;; Item not yet in zone: keep association.
	       ((< item start) cell)
	       ((>= item end)
		;; Item out of zone: follow associations in ACC.
		(let ((convert (assq parent acc)))
		  (if convert (cons item (cdr convert)) cell)))
	       (t
		;; Item is in zone...
		(let ((prev (org-list-get-prev-item item struct prevs)))
		  ;; Check if bullet needs to be changed.
		  (pcase (assoc (let ((b (org-list-get-bullet item struct))
				      (case-fold-search nil))
				  (cond ((string-match "[A-Z]\\." b) "A.")
					((string-match "[A-Z])" b) "A)")
					((string-match "[a-z]\\." b) "a.")
					((string-match "[a-z])" b) "a)")
					((string-match "[0-9]\\." b) "1.")
					((string-match "[0-9])" b) "1)")
					(t (org-trim b))))
				org-list-demote-modify-bullet)
		    (`(,_ . ,bullet)
		     (org-list-set-bullet
		      item struct (org-list-bullet-string bullet)))
		    (_ nil))
		  (cond
		   ;; First item indented but not parent: error
		   ((and (not prev) (or (not parent) (< parent start)))
		    (user-error "Cannot indent the first item of a list"))
		   ;; First item and parent indented: keep same
		   ;; parent.
		   ((not prev) (funcall set-assoc cell))
		   ;; Previous item not indented: reparent to it.
		   ((< prev start) (funcall set-assoc (cons item prev)))
		   ;; Previous item indented: reparent like it.
		   (t
		    (funcall set-assoc
			     (cons item (cdr (assq prev acc)))))))))))))
    (mapcar ind parents)))


\f
;;; Repairing structures

(defun org-list-use-alpha-bul-p (first struct prevs)
  "Non-nil if list starting at FIRST can have alphabetical bullets.

STRUCT is list structure.  PREVS is the alist of previous items,
as returned by `org-list-prevs-alist'."
  (and org-list-allow-alphabetical
       (catch 'exit
	 (let ((item first) (ascii 64) (case-fold-search nil))
	   ;; Pretend that bullets are uppercase and check if alphabet
	   ;; is sufficient, taking counters into account.
	   (while item
	     (let ((count (org-list-get-counter item struct)))
	       ;; Virtually determine current bullet
	       (if (and count (string-match-p "[a-zA-Z]" count))
		   ;; Counters are not case-sensitive.
		   (setq ascii (string-to-char (upcase count)))
		 (setq ascii (1+ ascii)))
	       ;; Test if bullet would be over z or Z.
	       (if (> ascii 90)
		   (throw 'exit nil)
		 (setq item (org-list-get-next-item item struct prevs)))))
	   ;; All items checked.  All good.
	   t))))

(defun org-list-inc-bullet-maybe (bullet)
  "Increment BULLET if applicable."
  (let ((case-fold-search nil))
    (cond
     ;; Num bullet: increment it.
     ((string-match "[0-9]+" bullet)
      (replace-match
       (number-to-string (1+ (string-to-number (match-string 0 bullet))))
       nil nil bullet))
     ;; Alpha bullet: increment it.
     ((string-match "[A-Za-z]" bullet)
      (replace-match
       (char-to-string (1+ (string-to-char (match-string 0 bullet))))
       nil nil bullet))
     ;; Unordered bullet: leave it.
     (t bullet))))

(defun org-list-struct-fix-bul (struct prevs)
  "Verify and correct bullets in STRUCT.
PREVS is the alist of previous items, as returned by
`org-list-prevs-alist'.

This function modifies STRUCT."
  (let ((case-fold-search nil)
	(fix-bul
	 ;; Set bullet of ITEM in STRUCT, depending on the type of
	 ;; first item of the list, the previous bullet and counter
	 ;; if any.
	 (lambda (item)
	   (let* ((prev (org-list-get-prev-item item struct prevs))
		  (prev-bul (and prev (org-list-get-bullet prev struct)))
		  (counter (org-list-get-counter item struct))
		  (bullet (org-list-get-bullet item struct))
		  (alphap (and (not prev)
			       (org-list-use-alpha-bul-p item struct prevs))))
	     (org-list-set-bullet
	      item struct
	      (org-list-bullet-string
	       (cond
		;; Alpha counter in alpha list: use counter.
		((and prev counter
		      (string-match "[a-zA-Z]" counter)
		      (string-match "[a-zA-Z]" prev-bul))
		 ;; Use cond to be sure `string-match' is used in
		 ;; both cases.
		 (let ((real-count
			(cond
			 ((string-match "[a-z]" prev-bul) (downcase counter))
			 ((string-match "[A-Z]" prev-bul) (upcase counter)))))
		   (replace-match real-count nil nil prev-bul)))
		;; Num counter in a num list: use counter.
		((and prev counter
		      (string-match "[0-9]+" counter)
		      (string-match "[0-9]+" prev-bul))
		 (replace-match counter nil nil prev-bul))
		;; No counter: increase, if needed, previous bullet.
		(prev
		 (org-list-inc-bullet-maybe (org-list-get-bullet prev struct)))
		;; Alpha counter at first item: use counter.
		((and counter (org-list-use-alpha-bul-p item struct prevs)
		      (string-match "[A-Za-z]" counter)
		      (string-match "[A-Za-z]" bullet))
		 (let ((real-count
			(cond
			 ((string-match "[a-z]" bullet) (downcase counter))
			 ((string-match "[A-Z]" bullet) (upcase counter)))))
		   (replace-match real-count nil nil bullet)))
		;; Num counter at first item: use counter.
		((and counter
		      (string-match "[0-9]+" counter)
		      (string-match "[0-9]+" bullet))
		 (replace-match counter nil nil bullet))
		;; First bullet is alpha uppercase: use "A".
		((and alphap (string-match "[A-Z]" bullet))
		 (replace-match "A" nil nil bullet))
		;; First bullet is alpha lowercase: use "a".
		((and alphap (string-match "[a-z]" bullet))
		 (replace-match "a" nil nil bullet))
		;; First bullet is num: use "1".
		((string-match "\\([0-9]+\\|[A-Za-z]\\)" bullet)
		 (replace-match "1" nil nil bullet))
		;; Not an ordered list: keep bullet.
		(t bullet))))))))
    (mapc fix-bul (mapcar #'car struct))))

(defun org-list-struct-fix-ind (struct parents &optional bullet-size)
  "Verify and correct indentation in STRUCT.

PARENTS is the alist of parents, as returned by
`org-list-parents-alist'.

If numeric optional argument BULLET-SIZE is set, assume all
bullets in list have this length to determine new indentation.

This function modifies STRUCT."
  (let* ((ancestor (org-list-get-top-point struct))
         (top-ind (org-list-get-ind ancestor struct))
         (new-ind
          (lambda (item)
            (let ((parent (org-list-get-parent item struct parents)))
              (if parent
                  ;; Indent like parent + length of parent's bullet +
		  ;; sub-list offset.
                  (org-list-set-ind
		   item struct (+ (or bullet-size
				      (length
				       (org-list-get-bullet parent struct)))
				  (org-list-get-ind parent struct)
				  org-list-indent-offset))
                ;; If no parent, indent like top-point.
		(org-list-set-ind item struct top-ind))))))
    (mapc new-ind (mapcar #'car (cdr struct)))))

(defun org-list-struct-fix-box (struct parents prevs &optional ordered)
  "Verify and correct checkboxes in STRUCT.

PARENTS is the alist of parents and PREVS is the alist of
previous items, as returned by, respectively,
`org-list-parents-alist' and `org-list-prevs-alist'.

If ORDERED is non-nil, a checkbox can only be checked when every
checkbox before it is checked too.  If there was an attempt to
break this rule, the function will return the blocking item.  In
all others cases, the return value will be nil.

This function modifies STRUCT."
  (let ((all-items (mapcar #'car struct))
	(set-parent-box
	 (lambda (item)
	   (let* ((box-list
		   (mapcar (lambda (child)
			     (org-list-get-checkbox child struct))
			   (org-list-get-children item struct parents))))
	     (org-list-set-checkbox
	      item struct
	      (cond
	       ((and (member "[ ]" box-list) (member "[X]" box-list)) "[-]")
	       ((member "[-]" box-list) "[-]")
	       ((member "[X]" box-list) "[X]")
	       ((member "[ ]" box-list) "[ ]")
	       ;; Parent has no boxed child: leave box as-is.
	       (t (org-list-get-checkbox item struct)))))))
	parent-list)
    ;; 1. List all parents with a checkbox.
    (mapc
     (lambda (e)
       (let* ((parent (org-list-get-parent e struct parents))
	      (parent-box-p (org-list-get-checkbox parent struct)))
	 (when (and parent-box-p (not (memq parent parent-list)))
	   (push parent parent-list))))
     all-items)
    ;; 2. Sort those parents by decreasing indentation.
    (setq parent-list (sort parent-list
			    (lambda (e1 e2)
			      (> (org-list-get-ind e1 struct)
				 (org-list-get-ind e2 struct)))))
    ;; 3. For each parent, get all children's checkboxes to determine
    ;;    and set its checkbox accordingly.
    (mapc set-parent-box parent-list)
    ;; 4. If ORDERED is set, see if we need to uncheck some boxes.
    (when ordered
      (let* ((box-list
	      (mapcar (lambda (e) (org-list-get-checkbox e struct)) all-items))
	     (after-unchecked (member "[ ]" box-list)))
	;; There are boxes checked after an unchecked one: fix that.
	(when (member "[X]" after-unchecked)
	  (let ((index (- (length struct) (length after-unchecked))))
	    (dolist (e (nthcdr index all-items))
	      (when (org-list-get-checkbox e struct)
		(org-list-set-checkbox e struct "[ ]")))
	    ;; Verify once again the structure, without ORDERED.
	    (org-list-struct-fix-box struct parents prevs nil)
	    ;; Return blocking item.
	    (nth index all-items)))))))

(defun org-list-struct-fix-item-end (struct)
  "Verify and correct each item end position in STRUCT.

This function modifies STRUCT."
  (let (end-list acc-end)
    (pcase-dolist (`(,pos . ,_) struct)
      (let ((ind-pos (org-list-get-ind pos struct))
	    (end-pos (org-list-get-item-end pos struct)))
	(unless (assq end-pos struct)
	  ;; To determine real ind of an ending position that is not
	  ;; at an item, we have to find the item it belongs to: it is
	  ;; the last item (ITEM-UP), whose ending is further than the
	  ;; position we're interested in.
	  (let ((item-up (assoc-default end-pos acc-end #'>)))
	    (push (cons
		   ;; Else part is for the bottom point.
		   (if item-up (+ (org-list-get-ind item-up struct) 2) 0)
		   end-pos)
		  end-list)))
	(push (cons ind-pos pos) end-list)
	(push (cons end-pos pos) acc-end)))
    (setq end-list (sort end-list (lambda (e1 e2) (< (cdr e1) (cdr e2)))))
    (org-list-struct-assoc-end struct end-list)))

(defun org-list-struct-apply-struct (struct old-struct)
  "Apply set difference between STRUCT and OLD-STRUCT to the buffer.

OLD-STRUCT is the structure before any modifications, and STRUCT
the structure to be applied.  The function will only modify parts
of the list which have changed.

Initial position of cursor is restored after the changes."
  (let* ((origin (point-marker))
	 (inlinetask-re (and (featurep 'org-inlinetask)
			     (org-inlinetask-outline-regexp)))
	 (item-re (org-item-re))
	 (shift-body-ind
	  ;; Shift the indentation between END and BEG by DELTA.
	  ;; Start from the line before END.
	  (lambda (end beg delta)
	    (goto-char end)
	    (skip-chars-backward " \r\t\n")
	    (beginning-of-line)
	    (while (or (> (point) beg)
		       (and (= (point) beg)
			    (not (looking-at item-re))))
	      (cond
	       ;; Skip inline tasks.
	       ((and inlinetask-re (looking-at inlinetask-re))
		(org-inlinetask-goto-beginning))
	       ;; Shift only non-empty lines.
	       ((looking-at-p "^[ \t]*\\S-")
		(indent-line-to (+ (current-indentation) delta))))
	      (forward-line -1))))
	 (modify-item
	  ;; Replace ITEM first line elements with new elements from
	  ;; STRUCT, if appropriate.
	  (lambda (item)
	    (goto-char item)
	    (let* ((new-ind (org-list-get-ind item struct))
		   (old-ind (current-indentation))
		   (new-bul (org-list-bullet-string
			     (org-list-get-bullet item struct)))
		   (old-bul (org-list-get-bullet item old-struct))
		   (new-box (org-list-get-checkbox item struct)))
	      (looking-at org-list-full-item-re)
	      ;; a.  Replace bullet
	      (unless (equal old-bul new-bul)
		(replace-match new-bul nil nil nil 1))
	      ;; b.  Replace checkbox.
	      (cond
	       ((equal (match-string 3) new-box))
	       ((and (match-string 3) new-box)
		(replace-match new-box nil nil nil 3))
	       ((match-string 3)
		(looking-at ".*?\\([ \t]*\\[[ X-]\\]\\)")
		(replace-match "" nil nil nil 1))
	       (t (let ((counterp (match-end 2)))
		    (goto-char (if counterp (1+ counterp) (match-end 1)))
		    (insert (concat new-box (unless counterp " "))))))
	      ;; c.  Indent item to appropriate column.
	      (unless (= new-ind old-ind)
		(delete-region (goto-char (point-at-bol))
			       (progn (skip-chars-forward " \t") (point)))
		(indent-to new-ind))))))
    ;; 1. First get list of items and position endings.  We maintain
    ;;    two alists: ITM-SHIFT, determining indentation shift needed
    ;;    at item, and END-LIST, a pseudo-alist where key is ending
    ;;    position and value point.
    (let (end-list acc-end itm-shift all-ends sliced-struct)
      (dolist (e old-struct)
	(let* ((pos (car e))
	       (ind-pos (org-list-get-ind pos struct))
	       (ind-old (org-list-get-ind pos old-struct))
	       (bul-pos (org-list-get-bullet pos struct))
	       (bul-old (org-list-get-bullet pos old-struct))
	       (ind-shift (- (+ ind-pos (length bul-pos))
			     (+ ind-old (length bul-old))))
	       (end-pos (org-list-get-item-end pos old-struct)))
	  (push (cons pos ind-shift) itm-shift)
	  (unless (assq end-pos old-struct)
	    ;; To determine real ind of an ending position that
	    ;; is not at an item, we have to find the item it
	    ;; belongs to: it is the last item (ITEM-UP), whose
	    ;; ending is further than the position we're
	    ;; interested in.
	    (let ((item-up (assoc-default end-pos acc-end #'>)))
	      (push (cons end-pos item-up) end-list)))
	  (push (cons end-pos pos) acc-end)))
      ;; 2. Slice the items into parts that should be shifted by the
      ;;    same amount of indentation.  Each slice follow the pattern
      ;;    (END BEG DELTA).  Slices are returned in reverse order.
      (setq all-ends (sort (append (mapcar #'car itm-shift)
				   (org-uniquify (mapcar #'car end-list)))
			   #'<)
	    acc-end (nreverse acc-end))
      (while (cdr all-ends)
	(let* ((up (pop all-ends))
	       (down (car all-ends))
	       (itemp (assq up struct))
	       (delta
		(if itemp (cdr (assq up itm-shift))
		  ;; If we're not at an item, there's a child of the
		  ;; item point belongs to above.  Make sure the less
		  ;; indented line in this slice has the same column
		  ;; as that child.
		  (let* ((child (cdr (assq up acc-end)))
			 (ind (org-list-get-ind child struct))
			 (min-ind most-positive-fixnum))
		    (save-excursion
		      (goto-char up)
		      (while (< (point) down)
			;; Ignore empty lines.  Also ignore blocks and
			;; drawers contents.
			(unless (looking-at-p "[ \t]*$")
			  (setq min-ind (min (current-indentation) min-ind))
			  (cond
			   ((and (looking-at "#\\+BEGIN\\(:\\|_\\S-+\\)")
				 (re-search-forward
				  (format "^[ \t]*#\\+END%s[ \t]*$"
					  (match-string 1))
				  down t)))
			   ((and (looking-at org-drawer-regexp)
				 (re-search-forward "^[ \t]*:END:[ \t]*$"
						    down t)))))
			(forward-line)))
		    (- ind min-ind)))))
	  (push (list down up delta) sliced-struct)))
      ;; 3. Shift each slice in buffer, provided delta isn't 0, from
      ;;    end to beginning.  Take a special action when beginning is
      ;;    at item bullet.
      (dolist (e sliced-struct)
	(unless (zerop (nth 2 e)) (apply shift-body-ind e))
	(let* ((beg (nth 1 e))
	       (cell (assq beg struct)))
	  (unless (or (not cell) (equal cell (assq beg old-struct)))
	    (funcall modify-item beg)))))
    ;; 4. Go back to initial position and clean marker.
    (goto-char origin)
    (move-marker origin nil)))

(defun org-list-write-struct (struct parents &optional old-struct)
  "Correct bullets, checkboxes and indentation in list at point.

STRUCT is the list structure.  PARENTS is the alist of parents,
as returned by `org-list-parents-alist'.

When non-nil, optional argument OLD-STRUCT is the reference
structure of the list.  It should be provided whenever STRUCT
doesn't correspond anymore to the real list in buffer."
  ;; Order of functions matters here: checkboxes and endings need
  ;; correct indentation to be set, and indentation needs correct
  ;; bullets.
  ;;
  ;; 0. Save a copy of structure before modifications
  (let ((old-struct (or old-struct (copy-tree struct))))
    ;; 1. Set a temporary, but coherent with PARENTS, indentation in
    ;;    order to get items endings and bullets properly
    (org-list-struct-fix-ind struct parents 2)
    ;; 2. Fix each item end to get correct prevs alist.
    (org-list-struct-fix-item-end struct)
    ;; 3. Get bullets right.
    (let ((prevs (org-list-prevs-alist struct)))
      (org-list-struct-fix-bul struct prevs)
      ;; 4. Now get real indentation.
      (org-list-struct-fix-ind struct parents)
      ;; 5. Eventually fix checkboxes.
      (org-list-struct-fix-box struct parents prevs))
    ;; 6. Apply structure modifications to buffer.
    (org-list-struct-apply-struct struct old-struct))
  ;; 7. Return the updated structure
  struct)


\f
;;; Misc Tools

(defun org-apply-on-list (function init-value &rest args)
  "Call FUNCTION on each item of the list at point.
FUNCTION must be called with at least one argument: INIT-VALUE,
that will contain the value returned by the function at the
previous item, plus ARGS extra arguments.

FUNCTION is applied on items in reverse order.

As an example, \(org-apply-on-list \(lambda \(result) \(1+ result)) 0)
will return the number of items in the current list.

Sublists of the list are skipped.  Cursor is always at the
beginning of the item."
  (let* ((struct (org-list-struct))
	 (prevs (org-list-prevs-alist struct))
	 (item (copy-marker (point-at-bol)))
	 (all (org-list-get-all-items (marker-position item) struct prevs))
	 (value init-value))
    (dolist (e (nreverse all))
      (goto-char e)
      (setq value (apply function value args)))
    (goto-char item)
    (move-marker item nil)
    value))

(defun org-list-set-item-visibility (item struct view)
  "Set visibility of ITEM in STRUCT to VIEW.

Possible values are: `folded', `children' or `subtree'.  See
`org-cycle' for more information."
  (cond
   ((eq view 'folded)
    (let ((item-end (org-list-get-item-end-before-blank item struct)))
      ;; Hide from eol
      (org-flag-region (save-excursion (goto-char item) (line-end-position))
		       item-end t 'outline)))
   ((eq view 'children)
    ;; First show everything.
    (org-list-set-item-visibility item struct 'subtree)
    ;; Then fold every child.
    (let* ((parents (org-list-parents-alist struct))
	   (children (org-list-get-children item struct parents)))
      (dolist (child children)
	(org-list-set-item-visibility child struct 'folded))))
   ((eq view 'subtree)
    ;; Show everything
    (let ((item-end (org-list-get-item-end item struct)))
      (org-flag-region item item-end nil 'outline)))))

(defun org-list-item-body-column (item)
  "Return column at which body of ITEM should start."
  (save-excursion
    (goto-char item)
    (looking-at "[ \t]*\\(\\S-+\\)")
    (+ (progn (goto-char (match-end 1)) (current-column))
       (if (and org-list-two-spaces-after-bullet-regexp
		(string-match-p org-list-two-spaces-after-bullet-regexp
				(match-string 1)))
	   2
	 1))))


\f
;;; Interactive functions

(defalias 'org-list-get-item-begin 'org-in-item-p)

(defun org-beginning-of-item ()
  "Go to the beginning of the current item.
Throw an error when not in a list."
  (interactive)
  (let ((begin (org-in-item-p)))
    (if begin (goto-char begin) (error "Not in an item"))))

(defun org-beginning-of-item-list ()
  "Go to the beginning item of the current list or sublist.
Throw an error when not in a list."
  (interactive)
  (let ((begin (org-in-item-p)))
    (if (not begin)
	(error "Not in an item")
      (goto-char begin)
      (let* ((struct (org-list-struct))
	     (prevs (org-list-prevs-alist struct)))
	(goto-char (org-list-get-list-begin begin struct prevs))))))

(defun org-end-of-item-list ()
  "Go to the end of the current list or sublist.
Throw an error when not in a list."
  (interactive)
  (let ((begin (org-in-item-p)))
    (if (not begin)
	(error "Not in an item")
      (goto-char begin)
      (let* ((struct (org-list-struct))
	     (prevs (org-list-prevs-alist struct)))
	(goto-char (org-list-get-list-end begin struct prevs))))))

(defun org-end-of-item ()
  "Go to the end of the current item.
Throw an error when not in a list."
  (interactive)
  (let ((begin (org-in-item-p)))
    (if (not begin)
	(error "Not in an item")
      (goto-char begin)
      (let ((struct (org-list-struct)))
	(goto-char (org-list-get-item-end begin struct))))))

(defun org-previous-item ()
  "Move to the beginning of the previous item.
Throw an error when not in a list.  Also throw an error when at
first item, unless `org-list-use-circular-motion' is non-nil."
  (interactive)
  (let ((item (org-in-item-p)))
    (if (not item)
	(error "Not in an item")
      (goto-char item)
      (let* ((struct (org-list-struct))
	     (prevs (org-list-prevs-alist struct))
	     (prevp (org-list-get-prev-item item struct prevs)))
	(cond
	 (prevp (goto-char prevp))
	 (org-list-use-circular-motion
	  (goto-char (org-list-get-last-item item struct prevs)))
	 (t (error "On first item")))))))

(defun org-next-item ()
  "Move to the beginning of the next item.
Throw an error when not in a list.  Also throw an error when at
last item, unless `org-list-use-circular-motion' is non-nil."
  (interactive)
  (let ((item (org-in-item-p)))
    (if (not item)
	(error "Not in an item")
      (goto-char item)
      (let* ((struct (org-list-struct))
	     (prevs (org-list-prevs-alist struct))
	     (prevp (org-list-get-next-item item struct prevs)))
	(cond
	 (prevp (goto-char prevp))
	 (org-list-use-circular-motion
	  (goto-char (org-list-get-first-item item struct prevs)))
	 (t (error "On last item")))))))

(defun org-move-item-down ()
  "Move the item at point down, i.e. swap with following item.
Sub-items (items with larger indentation) are considered part of
the item, so this really moves item trees."
  (interactive)
  (unless (org-at-item-p) (error "Not at an item"))
  (let* ((col (current-column))
	 (item (point-at-bol))
	 (struct (org-list-struct))
	 (prevs (org-list-prevs-alist struct))
	 (next-item (org-list-get-next-item (point-at-bol) struct prevs)))
    (unless (or next-item org-list-use-circular-motion)
      (user-error "Cannot move this item further down"))
    (if (not next-item)
	(setq struct (org-list-send-item item 'begin struct))
      (setq struct (org-list-swap-items item next-item struct))
      (goto-char
       (org-list-get-next-item item struct (org-list-prevs-alist struct))))
    (org-list-write-struct struct (org-list-parents-alist struct))
    (org-move-to-column col)))

(defun org-move-item-up ()
  "Move the item at point up, i.e. swap with previous item.
Sub-items (items with larger indentation) are considered part of
the item, so this really moves item trees."
  (interactive)
  (unless (org-at-item-p) (error "Not at an item"))
  (let* ((col (current-column))
	 (item (point-at-bol))
	 (struct (org-list-struct))
	 (prevs (org-list-prevs-alist struct))
	 (prev-item (org-list-get-prev-item (point-at-bol) struct prevs)))
    (unless (or prev-item org-list-use-circular-motion)
      (user-error "Cannot move this item further up"))
    (if (not prev-item)
	(setq struct (org-list-send-item item 'end struct))
      (setq struct (org-list-swap-items prev-item item struct)))
    (org-list-write-struct struct (org-list-parents-alist struct))
    (org-move-to-column col)))

(defun org-insert-item (&optional checkbox)
  "Insert a new item at the current level.
If cursor is before first character after bullet of the item, the
new item will be created before the current one.

If CHECKBOX is non-nil, add a checkbox next to the bullet.

Return t when things worked, nil when we are not in an item, or
item is invisible."
  (interactive "P")
  (let ((itemp (org-in-item-p))
	(pos (point)))
    ;; If cursor isn't is a list or if list is invisible, return nil.
    (unless (or (not itemp)
		(save-excursion
		  (goto-char itemp)
		  (org-invisible-p)))
      (if (save-excursion
	    (goto-char itemp)
	    (org-at-item-timer-p))
	  ;; Timer list: delegate to `org-timer-item'.
	  (progn (org-timer-item) t)
	(let* ((struct (save-excursion (goto-char itemp)
				       (org-list-struct)))
	       (prevs (org-list-prevs-alist struct))
	       ;; If we're in a description list, ask for the new term.
	       (desc (when (eq (org-list-get-list-type itemp struct prevs)
			       'descriptive)
		       " :: ")))
	  (setq struct (org-list-insert-item pos struct prevs checkbox desc))
	  (org-list-write-struct struct (org-list-parents-alist struct))
	  (when checkbox (org-update-checkbox-count-maybe))
	  (looking-at org-list-full-item-re)
	  (goto-char (if (and (match-beginning 4)
			      (save-match-data
				(string-match "[.)]" (match-string 1))))
			 (match-beginning 4)
		       (match-end 0)))
	  (when desc (backward-char 1))
	  t)))))

(defun org-list-repair ()
  "Fix indentation, bullets and checkboxes in the list at point."
  (interactive)
  (unless (org-at-item-p) (error "This is not a list"))
  (let* ((struct (org-list-struct))
	 (parents (org-list-parents-alist struct)))
    (org-list-write-struct struct parents)))

(defun org-cycle-list-bullet (&optional which)
  "Cycle through the different itemize/enumerate bullets.
This cycle the entire list level through the sequence:

   `-'  ->  `+'  ->  `*'  ->  `1.'  ->  `1)'

If WHICH is a valid string, use that as the new bullet.  If WHICH
is an integer, 0 means `-', 1 means `+' etc.  If WHICH is
`previous', cycle backwards."
  (interactive "P")
  (unless (org-at-item-p) (error "Not at an item"))
  (save-excursion
    (beginning-of-line)
    (let* ((struct (org-list-struct))
           (parents (org-list-parents-alist struct))
           (prevs (org-list-prevs-alist struct))
           (list-beg (org-list-get-first-item (point) struct prevs))
           (bullet (org-list-get-bullet list-beg struct))
	   (alpha-p (org-list-use-alpha-bul-p list-beg struct prevs))
	   (case-fold-search nil)
	   (current (cond
		     ((string-match "[a-z]\\." bullet) "a.")
		     ((string-match "[a-z])" bullet) "a)")
		     ((string-match "[A-Z]\\." bullet) "A.")
		     ((string-match "[A-Z])" bullet) "A)")
		     ((string-match "\\." bullet) "1.")
		     ((string-match ")" bullet) "1)")
		     (t (org-trim bullet))))
           ;; Compute list of possible bullets, depending on context.
	   (bullet-list
	    (append '("-" "+" )
		    ;; *-bullets are not allowed at column 0.
		    (unless (looking-at "\\S-") '("*"))
		    ;; Description items cannot be numbered.
		    (unless (or (eq org-plain-list-ordered-item-terminator ?\))
				(org-at-item-description-p))
		      '("1."))
		    (unless (or (eq org-plain-list-ordered-item-terminator ?.)
				(org-at-item-description-p))
		      '("1)"))
		    (unless (or (not alpha-p)
				(eq org-plain-list-ordered-item-terminator ?\))
				(org-at-item-description-p))
		      '("a." "A."))
		    (unless (or (not alpha-p)
				(eq org-plain-list-ordered-item-terminator ?.)
				(org-at-item-description-p))
		      '("a)" "A)"))))
	   (len (length bullet-list))
	   (item-index (- len (length (member current bullet-list))))
	   (get-value (lambda (index) (nth (mod index len) bullet-list)))
	   (new (cond
		 ((member which bullet-list) which)
		 ((numberp which) (funcall get-value which))
		 ((eq 'previous which) (funcall get-value (1- item-index)))
		 (t (funcall get-value (1+ item-index))))))
      ;; Use a short variation of `org-list-write-struct' as there's
      ;; no need to go through all the steps.
      (let ((old-struct (copy-tree struct)))
        (org-list-set-bullet list-beg struct (org-list-bullet-string new))
        (org-list-struct-fix-bul struct prevs)
        (org-list-struct-fix-ind struct parents)
        (org-list-struct-apply-struct struct old-struct)))))

;;;###autoload
(define-minor-mode org-list-checkbox-radio-mode
  "When turned on, use list checkboxes as radio buttons."
  :lighter " CheckBoxRadio"
  (unless (eq major-mode 'org-mode)
    (user-error "Cannot turn this mode outside org-mode buffers")))

(defun org-toggle-radio-button (&optional arg)
  "Toggle off all checkboxes and toggle on the one at point."
  (interactive "P")
  (if (not (org-at-item-p))
      (user-error "Cannot toggle checkbox outside of a list")
    (let* ((cpos (org-in-item-p))
	   (struct (org-list-struct))
	   (orderedp (org-entry-get nil "ORDERED"))
	   (parents (org-list-parents-alist struct))
	   (old-struct (copy-tree struct))
	   (cbox (org-list-get-checkbox cpos struct))
           (prevs (org-list-prevs-alist struct))
	   (start (org-list-get-list-begin (point-at-bol) struct prevs))
	   (new (unless (and cbox (equal arg '(4)) (equal start cpos))
		  "[ ]")))
      (dolist (pos (org-list-get-all-items
		    start struct (org-list-prevs-alist struct)))
	(org-list-set-checkbox pos struct new))
      (when new
	(org-list-set-checkbox
	 cpos struct
	 (cond ((equal arg '(4)) (unless cbox "[ ]"))
	       ((equal arg '(16)) (unless cbox "[-]"))
	       (t (if (equal cbox "[X]") "[ ]" "[X]")))))
      (org-list-struct-fix-box struct parents prevs orderedp)
      (org-list-struct-apply-struct struct old-struct)
      (org-update-checkbox-count-maybe))))

(defun org-at-radio-list-p ()
  "Is point at a list item with radio buttons?"
  (when (org-match-line (org-item-re))	;short-circuit
    (let* ((e (save-excursion (beginning-of-line) (org-element-at-point))))
      ;; Check we're really on a line with a bullet.
      (when (memq (org-element-type e) '(item plain-list))
	;; Look for ATTR_ORG attribute in the current plain list.
	(let ((plain-list (org-element-lineage e '(plain-list) t)))
	  (org-with-point-at (org-element-property :post-affiliated plain-list)
	    (let ((case-fold-search t)
		  (regexp "^[ \t]*#\\+attr_org:.* :radio \\(\\S-+\\)")
		  (begin (org-element-property :begin plain-list)))
	      (and (re-search-backward regexp begin t)
		   (not (string-equal "nil" (match-string 1)))))))))))

(defun org-toggle-checkbox (&optional toggle-presence)
  "Toggle the checkbox in the current line.

With prefix argument TOGGLE-PRESENCE, add or remove checkboxes.
With a double prefix argument, set the checkbox to \"[-]\".

When there is an active region, toggle status or presence of the
first checkbox there, and make every item inside have the same
status or presence, respectively.

If point is on a headline, apply this to all checkbox items in
the text below the heading, taking as reference the first item in
subtree, ignoring planning line and any drawer following it."
  (interactive "P")
  (if (org-at-radio-list-p)
      (org-toggle-radio-button toggle-presence)
    (save-excursion
      (let* (singlep
	     block-item
	     lim-up
	     lim-down
	     (orderedp (org-entry-get nil "ORDERED"))
	     (_bounds
	      ;; In a region, start at first item in region.
	      (cond
	       ((org-region-active-p)
		(let ((limit (region-end)))
		  (goto-char (region-beginning))
		  (if (org-list-search-forward (org-item-beginning-re) limit t)
		      (setq lim-up (point-at-bol))
		    (error "No item in region"))
		  (setq lim-down (copy-marker limit))))
	       ((org-at-heading-p)
		;; On a heading, start at first item after drawers and
		;; time-stamps (scheduled, etc.).
		(let ((limit (save-excursion (outline-next-heading) (point))))
		  (org-end-of-meta-data t)
		  (if (org-list-search-forward (org-item-beginning-re) limit t)
		      (setq lim-up (point-at-bol))
		    (error "No item in subtree"))
		  (setq lim-down (copy-marker limit))))
	       ;; Just one item: set SINGLEP flag.
	       ((org-at-item-p)
		(setq singlep t)
		(setq lim-up (point-at-bol)
		      lim-down (copy-marker (point-at-eol))))
	       (t (error "Not at an item or heading, and no active region"))))
	     ;; Determine the checkbox going to be applied to all items
	     ;; within bounds.
	     (ref-checkbox
	      (progn
		(goto-char lim-up)
		(let ((cbox (and (org-at-item-checkbox-p) (match-string 1))))
		  (cond
		   ((equal toggle-presence '(16)) "[-]")
		   ((equal toggle-presence '(4))
		    (unless cbox "[ ]"))
		   ((equal "[X]" cbox) "[ ]")
		   (t "[X]"))))))
	;; When an item is found within bounds, grab the full list at
	;; point structure, then: (1) set check-box of all its items
	;; within bounds to REF-CHECKBOX, (2) fix check-boxes of the
	;; whole list, (3) move point after the list.
	(goto-char lim-up)
	(while (and (< (point) lim-down)
		    (org-list-search-forward (org-item-beginning-re)
					     lim-down 'move))
	  (let* ((struct (org-list-struct))
		 (struct-copy (copy-tree struct))
		 (parents (org-list-parents-alist struct))
		 (prevs (org-list-prevs-alist struct))
		 (bottom (copy-marker (org-list-get-bottom-point struct)))
		 (items-to-toggle (cl-remove-if
				   (lambda (e) (or (< e lim-up) (> e lim-down)))
				   (mapcar #'car struct))))
	    (dolist (e items-to-toggle)
	      (org-list-set-checkbox
	       e struct
	       ;; If there is no box at item, leave as-is unless
	       ;; function was called with C-u prefix.
	       (let ((cur-box (org-list-get-checkbox e struct)))
		 (if (or cur-box (equal toggle-presence '(4)))
		     ref-checkbox
		   cur-box))))
	    (setq block-item (org-list-struct-fix-box
			      struct parents prevs orderedp))
	    ;; Report some problems due to ORDERED status of subtree.
	    ;; If only one box was being checked, throw an error, else,
	    ;; only signal problems.
	    (cond
	     ((and singlep block-item (> lim-up block-item))
	      (error
	       "Checkbox blocked because of unchecked box at line %d"
	       (org-current-line block-item)))
	     (block-item
	      (message
	       "Checkboxes were removed due to unchecked box at line %d"
	       (org-current-line block-item))))
	    (goto-char bottom)
	    (move-marker bottom nil)
	    (org-list-struct-apply-struct struct struct-copy)))
	(move-marker lim-down nil))))
  (org-update-checkbox-count-maybe))

(defun org-reset-checkbox-state-subtree ()
  "Reset all checkboxes in an entry subtree."
  (interactive "*")
  (if (org-before-first-heading-p)
      (error "Not inside a tree")
    (save-restriction
      (save-excursion
	(org-narrow-to-subtree)
	(org-show-subtree)
	(goto-char (point-min))
	(let ((end (point-max)))
	  (while (< (point) end)
	    (when (org-at-item-checkbox-p)
	      (replace-match "[ ]" t t nil 1))
	    (beginning-of-line 2)))
	(org-update-checkbox-count-maybe 'all)))))

(defun org-update-checkbox-count (&optional all)
  "Update the checkbox statistics in the current section.

This will find all statistic cookies like [57%] and [6/12] and
update them with the current numbers.

With optional prefix argument ALL, do this for the whole buffer."
  (interactive "P")
  (org-with-wide-buffer
   (let* ((cookie-re "\\(\\(\\[[0-9]*%\\]\\)\\|\\(\\[[0-9]*/[0-9]*\\]\\)\\)")
	  (box-re "^[ \t]*\\([-+*]\\|\\([0-9]+\\|[A-Za-z]\\)[.)]\\)[ \t]+\
\\(?:\\[@\\(?:start:\\)?\\([0-9]+\\|[A-Za-z]\\)\\][ \t]*\\)?\\(\\[[- X]\\]\\)")
          (cookie-data (or (org-entry-get nil "COOKIE_DATA") ""))
	  (recursivep
	   (or (not org-checkbox-hierarchical-statistics)
	       (string-match-p "\\<recursive\\>" cookie-data)))
	  (within-inlinetask (and (not all)
				  (featurep 'org-inlinetask)
				  (org-inlinetask-in-task-p)))
	  (end (cond (all (point-max))
		     (within-inlinetask
		      (save-excursion (outline-next-heading) (point)))
		     (t (save-excursion
			  (org-with-limited-levels (outline-next-heading))
			  (point)))))
	  (count-boxes
	   (lambda (item structs recursivep)
	     ;; Return number of checked boxes and boxes of all types
	     ;; in all structures in STRUCTS.  If RECURSIVEP is
	     ;; non-nil, also count boxes in sub-lists.  If ITEM is
	     ;; nil, count across the whole structure, else count only
	     ;; across subtree whose ancestor is ITEM.
	     (let ((c-on 0) (c-all 0))
	       (dolist (s structs (list c-on c-all))
		 (let* ((pre (org-list-prevs-alist s))
			(par (org-list-parents-alist s))
			(items
			 (cond
			  ((and recursivep item) (org-list-get-subtree item s))
			  (recursivep (mapcar #'car s))
			  (item (org-list-get-children item s par))
			  (t (org-list-get-all-items
			      (org-list-get-top-point s) s pre))))
			(cookies (delq nil (mapcar
					    (lambda (e)
					      (org-list-get-checkbox e s))
					    items))))
		   (cl-incf c-all (length cookies))
		   (cl-incf c-on (cl-count "[X]" cookies :test #'equal)))))))
	  cookies-list cache)
     ;; Move to start.
     (cond (all (goto-char (point-min)))
	   (within-inlinetask (org-back-to-heading t))
	   (t (org-with-limited-levels (outline-previous-heading))))
     ;; Build an alist for each cookie found.  The key is the position
     ;; at beginning of cookie and values ending position, format of
     ;; cookie, number of checked boxes to report and total number of
     ;; boxes.
     (while (re-search-forward cookie-re end t)
       (let ((context (save-excursion (backward-char)
				      (save-match-data (org-element-context)))))
	 (when (and (eq (org-element-type context) 'statistics-cookie)
                    (not (string-match-p "\\<todo\\>" cookie-data)))
	   (push
	    (append
	     (list (match-beginning 1) (match-end 1) (match-end 2))
	     (let* ((container
		     (org-element-lineage
		      context
		      '(drawer center-block dynamic-block inlinetask item
			       quote-block special-block verse-block)))
		    (beg (if container
			     (org-element-property :contents-begin container)
			   (save-excursion
			     (org-with-limited-levels
			      (outline-previous-heading))
			     (point)))))
	       (or (cdr (assq beg cache))
		   (save-excursion
		     (goto-char beg)
		     (let ((end
			    (if container
				(org-element-property :contents-end container)
			      (save-excursion
				(org-with-limited-levels (outline-next-heading))
				(point))))
			   structs)
		       (while (re-search-forward box-re end t)
			 (let ((element (org-element-at-point)))
			   (when (eq (org-element-type element) 'item)
			     (push (org-element-property :structure element)
				   structs)
			     ;; Skip whole list since we have its
			     ;; structure anyway.
			     (while (setq element (org-element-lineage
						   element '(plain-list)))
			       (goto-char
				(min (org-element-property :end element)
				     end))))))
		       ;; Cache count for cookies applying to the same
		       ;; area.  Then return it.
		       (let ((count
			      (funcall count-boxes
				       (and (eq (org-element-type container)
						'item)
					    (org-element-property
					     :begin container))
				       structs
				       recursivep)))
			 (push (cons beg count) cache)
			 count))))))
	    cookies-list))))
     ;; Apply alist to buffer.
     (dolist (cookie cookies-list)
       (let* ((beg (car cookie))
	      (end (nth 1 cookie))
	      (percent (nth 2 cookie))
	      (checked (nth 3 cookie))
	      (total (nth 4 cookie)))
	 (goto-char beg)
	 (insert
	  (if percent (format "[%d%%]" (floor (* 100.0 checked)
					      (max 1 total)))
	    (format "[%d/%d]" checked total)))
	 (delete-region (point) (+ (point) (- end beg)))
	 (when org-auto-align-tags (org-fix-tags-on-the-fly)))))))

(defun org-get-checkbox-statistics-face ()
  "Select the face for checkbox statistics.
The face will be `org-done' when all relevant boxes are checked.
Otherwise it will be `org-todo'."
  (if (match-end 1)
      (if (equal (match-string 1) "100%")
	  'org-checkbox-statistics-done
	'org-checkbox-statistics-todo)
    (if (and (> (match-end 2) (match-beginning 2))
	     (equal (match-string 2) (match-string 3)))
	'org-checkbox-statistics-done
      'org-checkbox-statistics-todo)))

(defun org-update-checkbox-count-maybe (&optional all)
  "Update checkbox statistics unless turned off by user.
With an optional argument ALL, update them in the whole buffer."
  (when (cdr (assq 'checkbox org-list-automatic-rules))
    (org-update-checkbox-count all))
  (run-hooks 'org-checkbox-statistics-hook))

(defvar org-last-indent-begin-marker (make-marker))
(defvar org-last-indent-end-marker (make-marker))
(defun org-list-indent-item-generic (arg no-subtree struct)
  "Indent a local list item including its children.
When number ARG is a negative, item will be outdented, otherwise
it will be indented.

If a region is active, all items inside will be moved.

If NO-SUBTREE is non-nil, only indent the item itself, not its
children.

STRUCT is the list structure.

Return t if successful."
  (save-excursion
    (let* ((regionp (org-region-active-p))
	   (rbeg (and regionp (region-beginning)))
	   (rend (and regionp (region-end)))
	   (top (org-list-get-top-point struct))
	   (parents (org-list-parents-alist struct))
	   (prevs (org-list-prevs-alist struct))
	   ;; Are we going to move the whole list?
	   (specialp
	    (and (not regionp)
		 (= top (point-at-bol))
		 (cdr (assq 'indent org-list-automatic-rules))
		 (if no-subtree
		     (user-error
		      "At first item: use S-M-<left/right> to move the whole list")
		   t))))
      ;; Determine begin and end points of zone to indent.  If moving
      ;; more than one item, save them for subsequent moves.
      (unless (and (memq last-command '(org-shiftmetaright org-shiftmetaleft))
		   (memq this-command '(org-shiftmetaright org-shiftmetaleft)))
	(if regionp
	    (progn
	      (set-marker org-last-indent-begin-marker rbeg)
	      (set-marker org-last-indent-end-marker rend))
	  (set-marker org-last-indent-begin-marker (point-at-bol))
	  (set-marker org-last-indent-end-marker
		      (cond
		       (specialp (org-list-get-bottom-point struct))
		       (no-subtree (1+ (point-at-bol)))
		       (t (org-list-get-item-end (point-at-bol) struct))))))
      (let* ((beg (marker-position org-last-indent-begin-marker))
	     (end (marker-position org-last-indent-end-marker)))
	(cond
	 ;; Special case: moving top-item with indent rule.
	 (specialp
	  (let* ((level-skip (org-level-increment))
		 (offset (if (< arg 0) (- level-skip) level-skip))
		 (top-ind (org-list-get-ind beg struct))
		 (old-struct (copy-tree struct)))
	    (if (< (+ top-ind offset) 0)
		(error "Cannot outdent beyond margin")
	      ;; Change bullet if necessary.
	      (when (and (= (+ top-ind offset) 0)
			 (string-match "\\*"
				       (org-list-get-bullet beg struct)))
		(org-list-set-bullet beg struct
				     (org-list-bullet-string "-")))
	      ;; Shift every item by OFFSET and fix bullets.  Then
	      ;; apply changes to buffer.
	      (pcase-dolist (`(,pos . ,_) struct)
		(let ((ind (org-list-get-ind pos struct)))
		  (org-list-set-ind pos struct (+ ind offset))))
	      (org-list-struct-fix-bul struct prevs)
	      (org-list-struct-apply-struct struct old-struct))))
	 ;; Forbidden move:
	 ((and (< arg 0)
	       ;; If only one item is moved, it mustn't have a child.
	       (or (and no-subtree
			(not regionp)
			(org-list-has-child-p beg struct))
		   ;; If a subtree or region is moved, the last item
		   ;; of the subtree mustn't have a child.
		   (let ((last-item (caar
				     (reverse
				      (cl-remove-if
				       (lambda (e) (>= (car e) end))
				       struct)))))
		     (org-list-has-child-p last-item struct))))
	  (error "Cannot outdent an item without its children"))
	 ;; Normal shifting
	 (t
	  (let* ((old-struct (copy-tree struct))
		 (new-parents
		  (if (< arg 0)
		      (org-list-struct-outdent beg end struct parents)
		    (org-list-struct-indent beg end struct parents prevs))))
	    (org-list-write-struct struct new-parents old-struct))
	  (org-update-checkbox-count-maybe))))))
  t)

(defun org-outdent-item ()
  "Outdent a local list item, but not its children.
If a region is active, all items inside will be moved."
  (interactive)
  (let ((regionp (org-region-active-p)))
    (cond
     ((or (org-at-item-p)
	  (and regionp
	       (save-excursion (goto-char (region-beginning))
			       (org-at-item-p))))
      (let ((struct (if (not regionp) (org-list-struct)
		      (save-excursion (goto-char (region-beginning))
				      (org-list-struct)))))
	(org-list-indent-item-generic -1 t struct)))
     (regionp (error "Region not starting at an item"))
     (t (error "Not at an item")))))

(defun org-indent-item ()
  "Indent a local list item, but not its children.
If a region is active, all items inside will be moved."
  (interactive)
  (let ((regionp (org-region-active-p)))
    (cond
     ((or (org-at-item-p)
	  (and regionp
	       (save-excursion (goto-char (region-beginning))
			       (org-at-item-p))))
      (let ((struct (if (not regionp) (org-list-struct)
		      (save-excursion (goto-char (region-beginning))
				      (org-list-struct)))))
	(org-list-indent-item-generic 1 t struct)))
     (regionp (error "Region not starting at an item"))
     (t (error "Not at an item")))))

(defun org-outdent-item-tree ()
  "Outdent a local list item including its children.
If a region is active, all items inside will be moved."
  (interactive)
  (let ((regionp (org-region-active-p)))
    (cond
     ((or (org-at-item-p)
	  (and regionp
	       (save-excursion (goto-char (region-beginning))
			       (org-at-item-p))))
      (let ((struct (if (not regionp) (org-list-struct)
		      (save-excursion (goto-char (region-beginning))
				      (org-list-struct)))))
	(org-list-indent-item-generic -1 nil struct)))
     (regionp (error "Region not starting at an item"))
     (t (error "Not at an item")))))

(defun org-indent-item-tree ()
  "Indent a local list item including its children.
If a region is active, all items inside will be moved."
  (interactive)
  (let ((regionp (org-region-active-p)))
    (cond
     ((or (org-at-item-p)
	  (and regionp
	       (save-excursion (goto-char (region-beginning))
			       (org-at-item-p))))
      (let ((struct (if (not regionp) (org-list-struct)
		      (save-excursion (goto-char (region-beginning))
				      (org-list-struct)))))
	(org-list-indent-item-generic 1 nil struct)))
     (regionp (error "Region not starting at an item"))
     (t (error "Not at an item")))))

(defvar org-tab-ind-state)
(defun org-cycle-item-indentation ()
  "Cycle levels of indentation of an empty item.

The first run indents the item, if applicable.  Subsequent runs
outdent it at meaningful levels in the list.  When done, item is
put back at its original position with its original bullet.

Return t at each successful move."
  (when (org-at-item-p)
    (let* ((struct (org-list-struct))
	   (item (line-beginning-position))
	   (ind (org-list-get-ind item struct)))
      ;; Accept empty items or if cycle has already started.
      (when (or (eq last-command 'org-cycle-item-indentation)
		(and (org-match-line org-list-full-item-re)
		     (>= (match-end 0)
			 (save-excursion
			   (goto-char (org-list-get-item-end item struct))
			   (skip-chars-backward " \t\n")
			   (point)))))
	(setq this-command 'org-cycle-item-indentation)
	(let ((prevs (org-list-prevs-alist struct))
	      (parents (org-list-parents-alist struct)))
	  (if (eq last-command 'org-cycle-item-indentation)
	      ;; When in the middle of the cycle, try to outdent.  If
	      ;; it fails, move point back to its initial position and
	      ;; reset cycle.
	      (pcase-let ((`(,old-ind . ,old-bul) org-tab-ind-state)
			  (allow-outdent
			   (lambda (struct prevs parents)
			     ;; Non-nil if current item can be
			     ;; outdented.
			     (and (not (org-list-get-next-item item nil prevs))
				  (not (org-list-has-child-p item struct))
				  (org-list-get-parent item struct parents)))))
		(cond
		 ((and (> ind old-ind)
		       (org-list-get-prev-item item nil prevs))
		  (org-list-indent-item-generic 1 t struct))
		 ((and (< ind old-ind)
		       (funcall allow-outdent struct prevs parents))
		  (org-list-indent-item-generic -1 t struct))
		 (t
		  (delete-region (line-beginning-position) (line-end-position))
		  (indent-to-column old-ind)
		  (insert old-bul " ")
		  (let* ((struct (org-list-struct))
			 (parents (org-list-parents-alist struct)))
		    (if (and (> ind old-ind)
			     ;; We were previously indenting item.  It
			     ;; is no longer possible.  Try to outdent
			     ;; from initial position.
			     (funcall allow-outdent
				      struct
				      (org-list-prevs-alist struct)
				      parents))
			(org-list-indent-item-generic -1 t struct)
		      (org-list-write-struct struct parents)
		      ;; Start cycle over.
		      (setq this-command 'identity)
		      t)))))
	    ;; If a cycle is starting, remember initial indentation
	    ;; and bullet, then try to indent.  If it fails, try to
	    ;; outdent.
	    (setq org-tab-ind-state
		  (cons ind (org-trim (org-current-line-string))))
	    (cond
	     ((org-list-get-prev-item item nil prevs)
	      (org-list-indent-item-generic 1 t struct))
	     ((and (not (org-list-get-next-item item nil prevs))
		   (org-list-get-parent item struct parents))
	      (org-list-indent-item-generic -1 t struct))
	     (t
	      ;; This command failed.  So will the following one.
	      ;; There's no point in starting the cycle.
	      (setq this-command 'identity)
	      (user-error "Cannot move item")))))))))

(defun org-sort-list
    (&optional with-case sorting-type getkey-func compare-func interactive?)
  "Sort list items.
The cursor may be at any item of the list that should be sorted.
Sublists are not sorted.  Checkboxes, if any, are ignored.

Sorting can be alphabetically, numerically, by date/time as given
by a time stamp, by a property or by priority.

Comparing entries ignores case by default.  However, with an
optional argument WITH-CASE, the sorting considers case as well,
if the current locale allows for it.

The command prompts for the sorting type unless it has been given
to the function through the SORTING-TYPE argument, which needs to
be a character, among ?n ?N ?a ?A ?t ?T ?f ?F ?x or ?X.  Here is
the detailed meaning of each character:

n   Numerically, by converting the beginning of the item to a number.
a   Alphabetically.  Only the first line of item is checked.
t   By date/time, either the first active time stamp in the entry, if
    any, or by the first inactive one.  In a timer list, sort the timers.
x   By \"checked\" status of a check list.

Capital letters will reverse the sort order.

If the SORTING-TYPE is ?f or ?F, then GETKEY-FUNC specifies
a function to be called with point at the beginning of the
record.  It must return a value that is compatible with COMPARE-FUNC,
the function used to compare entries.

Sorting is done against the visible part of the headlines, it
ignores hidden links.

A non-nil value for INTERACTIVE? is used to signal that this
function is being called interactively."
  (interactive (list current-prefix-arg nil nil nil t))
  (let* ((case-func (if with-case 'identity 'downcase))
         (struct (org-list-struct))
         (prevs (org-list-prevs-alist struct))
	 (start (org-list-get-list-begin (point-at-bol) struct prevs))
	 (end (org-list-get-list-end (point-at-bol) struct prevs))
	 (sorting-type
	  (or sorting-type
	      (progn
		(message
		 "Sort plain list: [a]lpha  [n]umeric  [t]ime  [f]unc  [x]checked  A/N/T/F/X means reversed:")
		(read-char-exclusive))))
	 (dcst (downcase sorting-type))
	 (getkey-func
	  (and (= dcst ?f)
	       (or getkey-func
		   (and interactive?
			(org-read-function "Function for extracting keys: "))
		   (error "Missing key extractor"))))
	 (sort-func
	  (cond
	   ((= dcst ?a) #'string-collate-lessp)
	   ((= dcst ?f)
	    (or compare-func
		(and interactive?
		     (org-read-function
		      (concat "Function for comparing keys "
			      "(empty for default `sort-subr' predicate): ")
		      'allow-empty))))
	   ((= dcst ?t) #'<)
	   ((= dcst ?x) #'string<))))
    (message "Sorting items...")
    (save-restriction
      (narrow-to-region start end)
      (goto-char (point-min))
      (let* ((case-fold-search nil)
	     (now (current-time))
	     (next-record (lambda ()
			    (skip-chars-forward " \r\t\n")
			    (or (eobp) (beginning-of-line))))
	     (end-record (lambda ()
			   (goto-char (org-list-get-item-end-before-blank
				       (point) struct))))
	     (value-to-sort
	      (lambda ()
		(when (looking-at "[ \t]*[-+*0-9.)]+\\([ \t]+\\[[- X]\\]\\)?[ \t]+")
		  (cond
		   ((= dcst ?n)
		    (string-to-number
		     (org-sort-remove-invisible
		      (buffer-substring (match-end 0) (point-at-eol)))))
		   ((= dcst ?a)
		    (funcall case-func
			     (org-sort-remove-invisible
			      (buffer-substring
			       (match-end 0) (point-at-eol)))))
		   ((= dcst ?t)
		    (cond
		     ;; If it is a timer list, convert timer to seconds
		     ((org-at-item-timer-p)
		      (org-timer-hms-to-secs (match-string 1)))
		     ((or (save-excursion
			    (re-search-forward org-ts-regexp (point-at-eol) t))
			  (save-excursion (re-search-forward org-ts-regexp-both
							     (point-at-eol) t)))
		      (org-time-string-to-seconds (match-string 0)))
		     (t (float-time now))))
		   ((= dcst ?x) (or (and (stringp (match-string 1))
					 (match-string 1))
				    ""))
		   ((= dcst ?f)
		    (if getkey-func
			(let ((value (funcall getkey-func)))
			  (if (stringp value)
			      (funcall case-func value)
			    value))
		      (error "Invalid key function `%s'" getkey-func)))
		   (t (error "Invalid sorting type `%c'" sorting-type)))))))
	(sort-subr (/= dcst sorting-type)
		   next-record
		   end-record
		   value-to-sort
		   nil
		   sort-func)
	;; Read and fix list again, as `sort-subr' probably destroyed
	;; its structure.
	(org-list-repair)
	(run-hooks 'org-after-sorting-entries-or-items-hook)
	(message "Sorting items...done")))))

(defun org-toggle-item (arg)
  "Convert headings or normal lines to items, items to normal lines.
If there is no active region, only the current line is considered.

If the first non blank line in the region is a headline, convert
all headlines to items, shifting text accordingly.

If it is an item, convert all items to normal lines.

If it is normal text, change region into a list of items.
With a prefix argument ARG, change the region in a single item."
  (interactive "P")
  (let ((shift-text
	 (lambda (ind end)
	   ;; Shift text in current section to IND, from point to END.
	   ;; The function leaves point to END line.
	   (let ((min-i 1000) (end (copy-marker end)))
	     ;; First determine the minimum indentation (MIN-I) of
	     ;; the text.
	     (save-excursion
	       (catch 'exit
		 (while (< (point) end)
		   (let ((i (current-indentation)))
		     (cond
		      ;; Skip blank lines and inline tasks.
		      ((looking-at "^[ \t]*$"))
		      ((looking-at org-outline-regexp-bol))
		      ;; We can't find less than 0 indentation.
		      ((zerop i) (throw 'exit (setq min-i 0)))
		      ((< i min-i) (setq min-i i))))
		   (forward-line))))
	     ;; Then indent each line so that a line indented to
	     ;; MIN-I becomes indented to IND.  Ignore blank lines
	     ;; and inline tasks in the process.
	     (let ((delta (- ind min-i)))
	       (while (< (point) end)
		 (unless (or (looking-at "^[ \t]*$")
			     (looking-at org-outline-regexp-bol))
		   (indent-line-to (+ (current-indentation) delta)))
		 (forward-line))))))
	(skip-blanks
	 (lambda (pos)
	   ;; Return beginning of first non-blank line, starting from
	   ;; line at POS.
	   (save-excursion
	     (goto-char pos)
	     (skip-chars-forward " \r\t\n")
	     (point-at-bol))))
	beg end)
    ;; Determine boundaries of changes.
    (if (org-region-active-p)
	(setq beg (funcall skip-blanks (region-beginning))
	      end (copy-marker (region-end)))
      (setq beg (point-at-bol)
	    end (copy-marker (point-at-eol))))
    ;; Depending on the starting line, choose an action on the text
    ;; between BEG and END.
    (org-with-limited-levels
     (save-excursion
       (goto-char beg)
       (cond
	;; Case 1. Start at an item: de-itemize.  Note that it only
	;;         happens when a region is active: `org-ctrl-c-minus'
	;;         would call `org-cycle-list-bullet' otherwise.
	((org-at-item-p)
	 (while (< (point) end)
	   (when (org-at-item-p)
	     (skip-chars-forward " \t")
	     (delete-region (point) (match-end 0)))
	   (forward-line)))
	;; Case 2. Start at an heading: convert to items.
	((org-at-heading-p)
	 ;; Remove metadata
	 (let (org-loop-over-headlines-in-active-region)
	   (org-list--delete-metadata))
	 (let* ((bul (org-list-bullet-string "-"))
		(bul-len (length bul))
		;; Indentation of the first heading.  It should be
		;; relative to the indentation of its parent, if any.
		(start-ind (save-excursion
			     (cond
			      ((not org-adapt-indentation) 0)
			      ((not (outline-previous-heading)) 0)
			      (t (length (match-string 0))))))
		;; Level of first heading.  Further headings will be
		;; compared to it to determine hierarchy in the list.
		(ref-level (org-reduced-level (org-outline-level))))
	   (while (< (point) end)
	     (let* ((level (org-reduced-level (org-outline-level)))
		    (delta (max 0 (- level ref-level)))
		    (todo-state (org-get-todo-state)))
	       ;; If current headline is less indented than the first
	       ;; one, set it as reference, in order to preserve
	       ;; subtrees.
	       (when (< level ref-level) (setq ref-level level))
	       ;; Remove metadata
	       (let (org-loop-over-headlines-in-active-region)
		 (org-list--delete-metadata))
	       ;; Remove stars and TODO keyword.
	       (let ((case-fold-search nil)) (looking-at org-todo-line-regexp))
	       (delete-region (point) (or (match-beginning 3)
					  (line-end-position)))
	       (insert bul)
	       (indent-line-to (+ start-ind (* delta bul-len)))
	       ;; Turn TODO keyword into a check box.
	       (when todo-state
		 (let* ((struct (org-list-struct))
			(old (copy-tree struct)))
		   (org-list-set-checkbox
		    (line-beginning-position)
		    struct
		    (if (member todo-state org-done-keywords)
			"[X]"
		      "[ ]"))
		   (org-list-write-struct struct
					  (org-list-parents-alist struct)
					  old)))
	       ;; Ensure all text down to END (or SECTION-END) belongs
	       ;; to the newly created item.
	       (let ((section-end (save-excursion
				    (or (outline-next-heading) (point)))))
		 (forward-line)
		 (funcall shift-text
			  (+ start-ind (* (1+ delta) bul-len))
			  (min end section-end)))))))
	;; Case 3. Normal line with ARG: make the first line of region
	;;         an item, and shift indentation of others lines to
	;;         set them as item's body.
	(arg (let* ((bul (org-list-bullet-string "-"))
		    (bul-len (length bul))
		    (ref-ind (current-indentation)))
	       (skip-chars-forward " \t")
	       (insert bul)
	       (forward-line)
	       (while (< (point) end)
		 ;; Ensure that lines less indented than first one
		 ;; still get included in item body.
		 (funcall shift-text
			  (+ ref-ind bul-len)
			  (min end (save-excursion (or (outline-next-heading)
						       (point)))))
		 (forward-line))))
	;; Case 4. Normal line without ARG: turn each non-item line
	;;         into an item.
	(t
	 (while (< (point) end)
	   (unless (or (org-at-heading-p) (org-at-item-p))
	     (when (looking-at "\\([ \t]*\\)\\(\\S-\\)")
	       (replace-match
		(concat "\\1" (org-list-bullet-string "-") "\\2"))))
	   (forward-line))))))))

\f
;;; Send and receive lists

(defun org-list-to-lisp (&optional delete)
  "Parse the list at point and maybe DELETE it.

Return a list whose car is a symbol of list type, among
`ordered', `unordered' and `descriptive'.  Then, each item is
a list of strings and other sub-lists.

For example, the following list:

  1. first item
     + sub-item one
     + [X] sub-item two
     more text in first item
  2. [@3] last item

is parsed as

 (ordered
  (\"first item\"
   (unordered
    (\"sub-item one\")
    (\"[X] sub-item two\"))
   \"more text in first item\")
  (\"[@3] last item\"))

Point is left at list's end."
  (letrec ((struct (org-list-struct))
	   (prevs (org-list-prevs-alist struct))
	   (parents (org-list-parents-alist struct))
	   (top (org-list-get-top-point struct))
	   (bottom (org-list-get-bottom-point struct))
	   (trim
	    (lambda (text)
	      ;; Remove indentation and final newline from TEXT.
	      (org-remove-indentation
	       (if (string-match-p "\n\\'" text)
		   (substring text 0 -1)
		 text))))
	   (parse-sublist
	    (lambda (e)
	      ;; Return a list whose car is list type and cdr a list
	      ;; of items' body.
	      (cons (org-list-get-list-type (car e) struct prevs)
		    (mapcar parse-item e))))
	   (parse-item
	    (lambda (e)
	      ;; Return a list containing counter of item, if any,
	      ;; text and any sublist inside it.
	      (let* ((end (org-list-get-item-end e struct))
		     (children (org-list-get-children e struct parents))
		     (body
		      (save-excursion
			(goto-char e)
			(looking-at "[ \t]*\\S-+[ \t]*")
			(list
			 (funcall
			  trim
			  (concat
			   (make-string (string-width (match-string 0)) ?\s)
			   (buffer-substring-no-properties
			    (match-end 0) (or (car children) end))))))))
		(while children
		  (let* ((child (car children))
			 (sub (org-list-get-all-items child struct prevs))
			 (last-in-sub (car (last sub))))
		    (push (funcall parse-sublist sub) body)
		    ;; Remove whole sub-list from children.
		    (setq children (cdr (memq last-in-sub children)))
		    ;; There is a chunk of text belonging to the item
		    ;; if last child doesn't end where next child
		    ;; starts or where item ends.
		    (let ((sub-end (org-list-get-item-end last-in-sub struct))
			  (next (or (car children) end)))
		      (when (/= sub-end next)
			(push (funcall
			       trim
			       (buffer-substring-no-properties sub-end next))
			      body)))))
		(nreverse body)))))
    ;; Store output, take care of cursor position and deletion of
    ;; list, then return output.
    (prog1 (funcall parse-sublist (org-list-get-all-items top struct prevs))
      (goto-char top)
      (when delete
	(delete-region top bottom)
	(when (and (not (looking-at "[ \t]*$")) (looking-at org-list-end-re))
	  (replace-match ""))))))

(defun org-list-make-subtree ()
  "Convert the plain list at point into a subtree."
  (interactive)
  (let ((item (org-in-item-p)))
    (unless item (error "Not in a list"))
    (goto-char item)
    (let ((level (pcase (org-current-level)
		   (`nil 1)
		   (l (1+ (org-reduced-level l)))))
	  (list (save-excursion (org-list-to-lisp t))))
      (insert (org-list-to-subtree list level) "\n"))))

(defun org-list-to-generic (list params)
  "Convert a LIST parsed through `org-list-to-lisp' to a custom format.

LIST is a list as returned by `org-list-to-lisp', which see.
PARAMS is a property list of parameters used to tweak the output
format.

Valid parameters are:

:backend, :raw

  Export back-end used as a basis to transcode elements of the
  list, when no specific parameter applies to it.  It is also
  used to translate its contents.  You can prevent this by
  setting :raw property to a non-nil value.

:splice

  When non-nil, only export the contents of the top most plain
  list, effectively ignoring its opening and closing lines.

:ustart, :uend

  Strings to start and end an unordered list.  They can also be
  set to a function returning a string or nil, which will be
  called with the depth of the list, counting from 1.

:ostart, :oend

  Strings to start and end an ordered list.  They can also be set
  to a function returning a string or nil, which will be called
  with the depth of the list, counting from 1.

:dstart, :dend

  Strings to start and end a descriptive list.  They can also be
  set to a function returning a string or nil, which will be
  called with the depth of the list, counting from 1.

:dtstart, :dtend, :ddstart, :ddend

  Strings to start and end a descriptive term.

:istart, :iend

  Strings to start or end a list item, and to start a list item
  with a counter.  They can also be set to a function returning
  a string or nil, which will be called with two arguments: the
  type of list and the depth of the item, counting from 1.

:icount

  Strings to start a list item with a counter.  It can also be
  set to a function returning a string or nil, which will be
  called with three arguments: the type of list, the depth of the
  item, counting from 1, and the counter.  Its value, when
  non-nil, has precedence over `:istart'.

:isep

  String used to separate items.  It can also be set to
  a function returning a string or nil, which will be called with
  two arguments: the type of list and the depth of the item,
  counting from 1.  It always start on a new line.

:ifmt

  Function to be applied to the contents of every item.  It is
  called with two arguments: the type of list and the contents.

:cbon, :cboff, :cbtrans

  String to insert, respectively, an un-checked check-box,
  a checked check-box and a check-box in transitional state."
  (require 'ox)
  (let* ((backend (plist-get params :backend))
	 (custom-backend
	  (org-export-create-backend
	   :parent (or backend 'org)
	   :transcoders
	   `((plain-list . ,(org-list--to-generic-plain-list params))
	     (item . ,(org-list--to-generic-item params))
	     (macro . (lambda (m c i) (org-element-macro-interpreter m nil))))))
	 data info)
    ;; Write LIST back into Org syntax and parse it.
    (with-temp-buffer
      (let ((org-inhibit-startup t)) (org-mode))
      (letrec ((insert-list
		(lambda (l)
		  (dolist (i (cdr l))
		    (funcall insert-item i (car l)))))
	       (insert-item
		(lambda (i type)
		  (let ((start (point)))
		    (insert (if (eq type 'ordered) "1. " "- "))
		    (dolist (e i)
		      (if (consp e) (funcall insert-list e)
			(insert e)
			(insert "\n")))
		    (beginning-of-line)
		    (save-excursion
		      (let ((ind (if (eq type 'ordered) 3 2)))
			(while (> (point) start)
			  (unless (looking-at-p "[ \t]*$")
			    (indent-to ind))
			  (forward-line -1))))))))
	(funcall insert-list list))
      (setf data
	    (org-element-map (org-element-parse-buffer) 'plain-list
	      #'identity nil t))
      (setf info (org-export-get-environment backend nil params)))
    (when (and backend (symbolp backend) (not (org-export-get-backend backend)))
      (user-error "Unknown :backend value"))
    (unless backend (require 'ox-org))
    ;; When ':raw' property has a non-nil value, turn all objects back
    ;; into Org syntax.
    (when (and backend (plist-get params :raw))
      (org-element-map data org-element-all-objects
	(lambda (object)
	  (org-element-set-element
	   object (org-element-interpret-data object)))))
    ;; We use a low-level mechanism to export DATA so as to skip all
    ;; usual pre-processing and post-processing, i.e., hooks, filters,
    ;; Babel code evaluation, include keywords and macro expansion,
    ;; and filters.
    (let ((output (org-export-data-with-backend data custom-backend info)))
      ;; Remove final newline.
      (if (org-string-nw-p output) (substring-no-properties output 0 -1) ""))))

(defun org-list--depth (element)
  "Return the level of ELEMENT within current plain list.
ELEMENT is either an item or a plain list."
  (cl-count-if (lambda (ancestor) (eq (org-element-type ancestor) 'plain-list))
	       (org-element-lineage element nil t)))

(defun org-list--trailing-newlines (string)
  "Return the number of trailing newlines in STRING."
  (with-temp-buffer
    (insert string)
    (skip-chars-backward " \t\n")
    (count-lines (line-beginning-position 2) (point-max))))

(defun org-list--generic-eval (value &rest args)
  "Evaluate VALUE according to its type.
VALUE is either nil, a string or a function.  In the latter case,
it is called with arguments ARGS."
  (cond ((null value) nil)
	((stringp value) value)
	((functionp value) (apply value args))
	(t (error "Wrong value: %s" value))))

(defun org-list--to-generic-plain-list (params)
  "Return a transcoder for `plain-list' elements.
PARAMS is a plist used to tweak the behavior of the transcoder."
  (let ((ustart (plist-get params :ustart))
	(uend (plist-get params :uend))
	(ostart (plist-get params :ostart))
	(oend (plist-get params :oend))
	(dstart (plist-get params :dstart))
	(dend (plist-get params :dend))
	(splice (plist-get params :splice))
	(backend (plist-get params :backend)))
    (lambda (plain-list contents info)
      (let* ((type (org-element-property :type plain-list))
	     (depth (org-list--depth plain-list))
	     (start (and (not splice)
			 (org-list--generic-eval
			  (pcase type
			    (`ordered ostart)
			    (`unordered ustart)
			    (_ dstart))
			  depth)))
	     (end (and (not splice)
		       (org-list--generic-eval
			(pcase type
			  (`ordered oend)
			  (`unordered uend)
			  (_ dend))
			depth))))
	;; Make sure trailing newlines in END appear in the output by
	;; setting `:post-blank' property to their number.
	(when end
	  (org-element-put-property
	   plain-list :post-blank (org-list--trailing-newlines end)))
	;; Build output.
	(concat (and start (concat start "\n"))
		(if (or start end splice (not backend))
		    contents
		  (org-export-with-backend backend plain-list contents info))
		end)))))

(defun org-list--to-generic-item (params)
  "Return a transcoder for `item' elements.
PARAMS is a plist used to tweak the behavior of the transcoder."
  (let ((backend (plist-get params :backend))
	(istart (plist-get params :istart))
	(iend (plist-get params :iend))
	(isep (plist-get params :isep))
	(icount (plist-get params :icount))
	(ifmt (plist-get params :ifmt))
	(cboff (plist-get params :cboff))
	(cbon  (plist-get params :cbon))
	(cbtrans (plist-get params :cbtrans))
	(dtstart (plist-get params :dtstart))
	(dtend (plist-get params :dtend))
	(ddstart (plist-get params :ddstart))
	(ddend (plist-get params :ddend)))
    (lambda (item contents info)
      (let* ((type
	      (org-element-property :type (org-element-property :parent item)))
	     (tag (org-element-property :tag item))
	     (depth (org-list--depth item))
	     (separator (and (org-export-get-next-element item info)
			     (org-list--generic-eval isep type depth)))
	     (closing (pcase (org-list--generic-eval iend type depth)
			((or `nil "") "\n")
			((and (guard separator) s)
			 (if (equal (substring s -1) "\n") s (concat s "\n")))
			(s s))))
	;; When a closing line or a separator is provided, make sure
	;; its trailing newlines are taken into account when building
	;; output.  This is done by setting `:post-blank' property to
	;; the number of such lines in the last line to be added.
	(let ((last-string (or separator closing)))
	  (when last-string
	    (org-element-put-property
	     item
	     :post-blank
	     (max (1- (org-list--trailing-newlines last-string)) 0))))
	;; Build output.
	(concat
	 (let ((c (org-element-property :counter item)))
	   (if (and c icount) (org-list--generic-eval icount type depth c)
	     (org-list--generic-eval istart type depth)))
	 (let ((body
		(if (or istart iend icount ifmt cbon cboff cbtrans (not backend)
			(and (eq type 'descriptive)
			     (or dtstart dtend ddstart ddend)))
		    (concat
		     (pcase (org-element-property :checkbox item)
		       (`on cbon)
		       (`off cboff)
		       (`trans cbtrans))
		     (and tag
			  (concat dtstart
				  (if backend
				      (org-export-data-with-backend
				       tag backend info)
				    (org-element-interpret-data tag))
				  dtend))
		     (and tag ddstart)
		     (let ((contents
			    (if (= (length contents) 0) ""
			      (substring contents 0 -1))))
		       (if ifmt (org-list--generic-eval ifmt type contents)
			 contents))
		     (and tag ddend))
		  (org-export-with-backend backend item contents info))))
	   ;; Remove final newline.
	   (if (equal body "") ""
	     (substring (org-element-normalize-string body) 0 -1)))
	 closing
	 separator)))))

(defun org-list-to-latex (list &optional params)
  "Convert LIST into a LaTeX list.
LIST is a parsed plain list, as returned by `org-list-to-lisp'.
PARAMS is a property list with overruling parameters for
`org-list-to-generic'.  Return converted list as a string."
  (require 'ox-latex)
  (org-list-to-generic list (org-combine-plists '(:backend latex) params)))

(defun org-list-to-html (list &optional params)
  "Convert LIST into a HTML list.
LIST is a parsed plain list, as returned by `org-list-to-lisp'.
PARAMS is a property list with overruling parameters for
`org-list-to-generic'.  Return converted list as a string."
  (require 'ox-html)
  (org-list-to-generic list (org-combine-plists '(:backend html) params)))

(defun org-list-to-texinfo (list &optional params)
  "Convert LIST into a Texinfo list.
LIST is a parsed plain list, as returned by `org-list-to-lisp'.
PARAMS is a property list with overruling parameters for
`org-list-to-generic'.  Return converted list as a string."
  (require 'ox-texinfo)
  (org-list-to-generic list (org-combine-plists '(:backend texinfo) params)))

(defun org-list-to-org (list &optional params)
  "Convert LIST into an Org plain list.
LIST is as returned by `org-list-parse-list'.  PARAMS is a property list
with overruling parameters for `org-list-to-generic'."
  (let* ((make-item
	  (lambda (type _depth &optional c)
	    (concat (if (eq type 'ordered) "1. " "- ")
		    (and c (format "[@%d] " c)))))
	 (defaults
	   (list :istart make-item
		 :icount make-item
		 :ifmt (lambda (_type contents)
			 (replace-regexp-in-string "\n" "\n  " contents))
		 :dtend " :: "
		 :cbon "[X] "
		 :cboff "[ ] "
		 :cbtrans "[-] ")))
    (org-list-to-generic list (org-combine-plists defaults params))))

(defun org-list-to-subtree (list &optional start-level params)
  "Convert LIST into an Org subtree.
LIST is as returned by `org-list-to-lisp'.  Subtree starts at
START-LEVEL or level 1 if nil.  PARAMS is a property list with
overruling parameters for `org-list-to-generic'."
  (let* ((blank (pcase (cdr (assq 'heading org-blank-before-new-entry))
		  (`t t)
		  (`auto (save-excursion
			   (org-with-limited-levels (outline-previous-heading))
			   (org-previous-line-empty-p)))))
	 (level (or start-level 1))
	 (make-stars
	  (lambda (_type depth &optional _count)
	    ;; Return the string for the heading, depending on DEPTH
	    ;; of current sub-list.
	    (let ((oddeven-level (+ level (1- depth))))
	      (concat (make-string (if org-odd-levels-only
				       (1- (* 2 oddeven-level))
				     oddeven-level)
				   ?*)
		      " ")))))
    (org-list-to-generic
     list
     (org-combine-plists
      (list :splice t
	    :istart make-stars
	    :icount make-stars
	    :dtstart " " :dtend " "
	    :isep (if blank "\n\n" "\n")
	    :cbon "DONE " :cboff "TODO " :cbtrans "TODO ")
      params))))

(provide 'org-list)

;; Local variables:
;; generated-autoload-file: "org-loaddefs.el"
;; End:

;;; org-list.el ends here