;; notmuch-hello.el --- welcome to notmuch, a frontend
;;
;; Copyright © David Edmondson
;;
;; This file is part of Notmuch.
;;
;; Notmuch 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.
;;
;; Notmuch 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 Notmuch.  If not, see <http://www.gnu.org/licenses/>.
;;
;; Authors: David Edmondson <dme@dme.org>

(require 'widget)

(require 'notmuch-lib)

(defvar notmuch-hello-searches-to-save 10)
(defvar notmuch-hello-search-width 60)

(defvar notmuch-hello-recent-searches nil)

(defun notmuch-hello-save-search (search)
  (if (not (memq search notmuch-hello-recent-searches))
      (push search notmuch-hello-recent-searches))
  (if (> (length notmuch-hello-recent-searches)
	 notmuch-hello-searches-to-save)
      (setq notmuch-hello-recent-searches (butlast notmuch-hello-recent-searches))))

(defun notmuch-hello-trim (search)
  "Trim whitespace."
  (if (string-match "^[[:space:]]*\\(.*[^[:space:]]\\)[[:space:]]*$" search)
      (match-string 1 search)
    search))

(defun notmuch-hello-search (search)
  (let ((search (notmuch-hello-trim search)))
    (notmuch-hello-save-search search)
    (notmuch-search search)))

(defun notmuch-hello ()
  (interactive)

  (switch-to-buffer "*notmuch-hello*")
  (kill-all-local-variables)
  (let ((inhibit-read-only t))
    (erase-buffer))

  (let ((all (overlay-lists)))
    ;; Delete all the overlays.
    (mapcar 'delete-overlay (car all))
    (mapcar 'delete-overlay (cdr all)))

  (widget-insert "\nWelcome to notmuch.\n\n")
  (let ((start (point)))
    (widget-insert "Search: ")
    (widget-create 'editable-field
		   :size notmuch-hello-search-width
		   :action (lambda (widget &rest ignore)
			     (let ((search (widget-value widget)))
			       (notmuch-hello-search search))))
    (widget-insert "\n")
    (indent-rigidly start (point) 4))

  (when notmuch-hello-recent-searches
    (widget-insert "\nRecent searches:\n\n")
    (let ((start (point)))
      (mapcar '(lambda (search)
		 (widget-create 'editable-field
				:size notmuch-hello-search-width
				:action (lambda (widget &rest ignore)
					  (let ((search (widget-value widget)))
					    (notmuch-hello-search search)))
				search)
		 (widget-insert "\n"))
	      notmuch-hello-recent-searches)
      (indent-rigidly start (point) 4)))

  (widget-insert "\nFolders:\n\n")
  (let ((start (point)))
    (mapcar '(lambda (folder)
	       (let ((w (widget-create 'push-button
				       :notify (lambda (widget &rest ignore)
						 (notmuch-search (widget-get widget :notmuch-search-terms)))
				       "open")))
		 (widget-put w :notmuch-search-terms (cdr folder)))
	       (widget-insert (format " %6s %s\n" (notmuch-folder-count (cdr folder)) (car folder))))
	    notmuch-folders)
    (indent-rigidly start (point) 4))

  (widget-insert "\nAll tags:\n\n")
  (let ((start (point)))
    (mapcar '(lambda (tag)
	       (let ((w (widget-create 'push-button
				       :notify (lambda (widget &rest ignore)
						 (notmuch-search (widget-get widget :notmuch-search-terms)))
				       "open")))
		 (widget-put w :notmuch-search-terms (concat "tag:" tag)))
	       (widget-insert (format " %6s %s\n" (notmuch-folder-count
						   (concat "tag:" tag))
				      tag)))
	    (process-lines notmuch-command "search-tags"))
    (indent-rigidly start (point) 4))

  (use-local-map widget-keymap)
  (local-set-key "=" 'notmuch-hello)
  (local-set-key "q" '(lambda () (interactive) (kill-buffer (current-buffer))))

  (widget-setup)

  ;; Always put point inside the `search' widget, which we know is
  ;; first.
  (goto-char (point-min))
  (widget-forward 1))