;;; cc-menus.el --- imenu support for CC Mode

;; Copyright (C) 1985, 1987, 1992-2021 Free Software Foundation, Inc.

;; Authors:    1998- Martin Stjernholm
;;             1992-1999 Barry A. Warsaw
;;             1987 Dave Detlefs
;;             1987 Stewart Clamen
;;             1985 Richard M. Stallman
;; Maintainer: bug-cc-mode@gnu.org
;; Created:    22-Apr-1997 (split from cc-mode.el)
;; Keywords:   c languages
;; Package:    cc-mode

;; 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:

;;; Code:

(eval-when-compile
  (let ((load-path
	 (if (and (boundp 'byte-compile-dest-file)
		  (stringp byte-compile-dest-file))
	     (cons (file-name-directory byte-compile-dest-file) load-path)
	   load-path)))
    (load "cc-bytecomp" nil t)))

(cc-require 'cc-defs)

;; The things referenced in imenu, which we don't require.
(cc-bytecomp-defvar imenu-case-fold-search)
(cc-bytecomp-defvar imenu-generic-expression)
(cc-bytecomp-defvar imenu-create-index-function)
(cc-bytecomp-defun c-literal-limits)

\f
;; imenu integration
(defvar cc-imenu-c-prototype-macro-regexp nil
  "RE matching macro names used to conditionally specify function prototypes.

For example:

    #ifdef __STDC__
      #define _P(x) x
    #else
      #define _P(x) /*nothing*/
    #endif

    int main _P( (int argc, char *argv[]) )

A sample value might look like: `\\(_P\\|_PROTO\\)'.")

;;			  *Warning for cc-mode developers*
;;
;; `cc-imenu-objc-generic-expression' elements depend on
;; `cc-imenu-c++-generic-expression'. So if you change this
;; expression, you need to change following variables,
;; `cc-imenu-objc-generic-expression-*-index',
;; too. `cc-imenu-objc-function' uses these *-index variables, in
;; order to know where the each regexp *group \\(foobar\\)* elements
;; are started.
;;
;; *-index variables are initialized during `cc-imenu-objc-generic-expression'
;; being initialized.
;;

(defvar cc-imenu-c++-generic-expression
  `(
    ;; Try to match ::operator definitions first. Otherwise `X::operator new ()'
    ;; will be incorrectly recognized as function `new ()' because the regexps
    ;; work by backtracking from the end of the definition.
    (nil
     ,(concat
       "^\\<.*"
       "[^" c-alnum "_:<>~]"                  ; match any non-identifier char
                                              ; (note: this can be `\n')
       "\\("
	  "\\([" c-alnum "_:<>~]*::\\)?"      ; match an operator
          "operator\\>[ \t]*"
          "\\(()\\|[^(]*\\)"                  ; special case for `()' operator
       "\\)"

       "[ \t]*([^)]*)[ \t]*[^ \t;]"           ; followed by ws, arg list,
                                              ; require something other than
                                              ; a `;' after the (...) to
                                              ; avoid prototypes.  Can't
                                              ; catch cases with () inside
                                              ; the parentheses surrounding
                                              ; the parameters.  e.g.:
                                              ; `int foo(int a=bar()) {...}'
       ) 1)
    ;; Special case to match a line like `main() {}'
    ;; e.g. no return type, not even on the previous line.
    (nil
     ,(concat
       "^"
       "\\([" c-alpha "_][" c-alnum "_:<>~]*\\)" ; match function name
       "[ \t]*("			      ; see above, BUT
       "[ \t]*\\([^ \t(*][^)]*\\)?)"          ; the arg list must not start
       "[ \t]*[^ \t;(]"                       ; with an asterisk or parentheses
       ) 1)
    ;; General function name regexp
    (nil
     ,(concat
       "^\\<"                                 ; line MUST start with word char
       ;; \n added to prevent overflow in regexp matcher.
       ;; https://lists.gnu.org/r/emacs-pretest-bug/2007-02/msg00021.html
       "[^()\n]*"                             ; no parentheses before
       "[^" c-alnum "_:<>~]"                  ; match any non-identifier char
       "\\([" c-alpha "_][" c-alnum "_:<>~]*\\)" ; match function name
       "\\([ \t\n]\\|\\\\\n\\)*("	      ; see above, BUT the arg list
       "\\([ \t\n]\\|\\\\\n\\)*"	      ; must not start
       "\\([^ \t\n(*]"			      ; with an asterisk or parentheses
       "[^()]*\\(([^()]*)[^()]*\\)*"	      ; Maybe function pointer arguments
       "\\)?)"
       "\\([ \t\n]\\|\\\\\n\\)*[^ \t\n;(]"
       ) 1)
    ;; Special case for definitions using phony prototype macros like:
    ;; `int main _PROTO( (int argc,char *argv[]) )'.
    ;; This case is only included if cc-imenu-c-prototype-macro-regexp is set.
    ;; Only supported in c-code, so no `:<>~' chars in function name!
    ,@(if cc-imenu-c-prototype-macro-regexp
            `((nil
                 ,(concat
                   "^\\<.*"                   ; line MUST start with word char
		   "[^" c-alnum "_]"          ; match any non-identifier char
		   "\\([" c-alpha "_][" c-alnum "_]*\\)" ; match function name
                   "[ \t]*"                   ; whitespace before macro name
                   cc-imenu-c-prototype-macro-regexp
                   "[ \t]*("                  ; ws followed by first paren.
                   "[ \t]*([^)]*)[ \t]*)[ \t]*[^ \t;]" ; see above
                   ) 1)))
    ;; Class definitions
    ("Class"
     ,(concat
         "^"                                  ; beginning of line is required
         "\\(template[ \t]*<[^>]+>[ \t]*\\)?" ; there may be a `template <...>'
         "\\(class\\|struct\\)[ \t]+"
         "\\("                                ; the string we want to get
	 "[" c-alnum "_]+"                    ; class name
         "\\(<[^>]+>\\)?"                     ; possibly explicitly specialized
         "\\)"
         "\\([ \t\n]\\|\\\\\n\\)*[:{]"
         ) 3))
  "Imenu generic expression for C++ mode.  See `imenu-generic-expression'.")

(defvar cc-imenu-c-generic-expression
  cc-imenu-c++-generic-expression
  "Imenu generic expression for C mode.  See `imenu-generic-expression'.")


;; Auxiliary regexps for Java try to match their trailing whitespace where
;; appropriate, but _not_ starting whitespace.

(defconst cc-imenu-java-ellipsis-regexp
  (concat
   "\\.\\{3\\}"
   "[ \t\n\r]*"))

(defun cc-imenu-java-build-type-args-regex (depth)
  "Builds regexp for type arguments list with DEPTH allowed
nested angle brackets constructs."
  (if (> depth 0)
      (concat "<"
		"[][.," c-alnum "_? \t\n\r]+"
		(if (> depth 1)
		    "\\(")
		(cc-imenu-java-build-type-args-regex (1- depth))
		(if (> depth 1)
		  (concat "[][.," c-alnum "_? \t\n\r]*"
			  "\\)*"))
	      ">")))

(defconst cc-imenu-java-type-spec-regexp
  (concat
   ;; zero or more identifiers followed by a dot
   "\\("
     "[" c-alpha "_][" c-alnum "_]*\\."
   "\\)*"
   ;; a single mandatory identifier without a dot
   "[" c-alpha "_][" c-alnum "_]*"
   ;; then choice:
   "\\("
   ;; (option 1) type arguments list which _may_ be followed with brackets
   ;; and/or spaces, then optional variable arity
     "[ \t\n\r]*"
     (cc-imenu-java-build-type-args-regex 3)
     "[][ \t\n\r]*"
     "\\(" cc-imenu-java-ellipsis-regexp "\\)?"
   "\\|"
   ;; (option 2) just brackets and/or spaces (there should be at least one),
   ;; then optional variable arity
     "[][ \t\n\r]+"
     "\\(" cc-imenu-java-ellipsis-regexp "\\)?"
   "\\|"
   ;; (option 3) just variable arity
     cc-imenu-java-ellipsis-regexp
   "\\)"))

(defconst cc-imenu-java-comment-regexp
  (concat
   "/"
   "\\("
   ;; a traditional comment
     "\\*"
     "\\("
       "[^*]"
     "\\|"
       "\\*+[^/*]"
     "\\)*"
     "\\*+/"
   "\\|"
   ;; an end-of-line comment
     "/[^\n\r]*[\n\r]"
   "\\)"
  "[ \t\n\r]*"
   ))

;; Comments are allowed before the argument, after any of the
;; modifiers and after the identifier.
(defconst cc-imenu-java-method-arg-regexp
  (concat
   "\\(" cc-imenu-java-comment-regexp "\\)*"
   ;; optional modifiers
   "\\("
     ;; a modifier is either an annotation or "final"
     "\\("
       "@[" c-alpha "_]"
       "[" c-alnum "._]*"
       ;; TODO support element-value pairs!
     "\\|"
       "final"
     "\\)"
     ;; a modifier ends with comments and/or ws
     "\\("
       "\\(" cc-imenu-java-comment-regexp "\\)+"
     "\\|"
       "[ \t\n\r]+"
       "\\(" cc-imenu-java-comment-regexp "\\)*"
     "\\)"
   "\\)*"
   ;; type spec
   cc-imenu-java-type-spec-regexp
   ;; identifier
   "[" c-alpha "_]"
   "[" c-alnum "_]*"
   ;; optional comments and/or ws
   "[ \t\n\r]*"
   "\\(" cc-imenu-java-comment-regexp "\\)*"
   ))

(defconst cc-imenu-java-generic-expression
  `((nil
     ,(concat
       cc-imenu-java-type-spec-regexp
       "\\("				      ; method name which gets captured
					      ; into index
         "[" c-alpha "_]"
	 "[" c-alnum "_]*"
       "\\)"
       "[ \t\n\r]*"
       ;; An argument list that contains zero or more arguments.
       (concat
	"("
	"[ \t\n\r]*"
	"\\("
	  "\\(" cc-imenu-java-method-arg-regexp ",[ \t\n\r]*\\)*"
	  cc-imenu-java-method-arg-regexp
	"\\)?"
	")"
	"[.,_" c-alnum " \t\n\r]*"	      ; throws etc.
	"{"
	)) 7))
  "Imenu generic expression for Java mode.  See `imenu-generic-expression'.")


;; Internal variables
(defvar cc-imenu-objc-generic-expression-noreturn-index nil)
(defvar cc-imenu-objc-generic-expression-general-func-index nil)
(defvar cc-imenu-objc-generic-expression-proto-index nil)
(defvar cc-imenu-objc-generic-expression-objc-base-index nil)

(defvar cc-imenu-objc-generic-expression
  (concat
   ;;
   ;; For C
   ;;
   ;; > Special case to match a line like `main() {}'
   ;; > e.g. no return type, not even on the previous line.
   ;; Pick a token by (match-string 1)
   (car (cdr (nth 1 cc-imenu-c++-generic-expression))) ; -> index += 2
   (prog2 (setq cc-imenu-objc-generic-expression-noreturn-index 1) "")
   "\\|"
   ;; > General function name regexp
   ;; Pick a token by  (match-string 3)
   (car (cdr (nth 2 cc-imenu-c++-generic-expression))) ; -> index += 6
   (prog2 (setq cc-imenu-objc-generic-expression-general-func-index 3) "")
   ;; > Special case for definitions using phony prototype macros like:
   ;; > `int main _PROTO( (int argc,char *argv[]) )'.
   ;; Pick a token by  (match-string 8)
   (if cc-imenu-c-prototype-macro-regexp
       (concat
	"\\|"
	(car (cdr (nth 3 cc-imenu-c++-generic-expression))) ; -> index += 1
	(prog2 (setq cc-imenu-objc-generic-expression-objc-base-index 10) "")
	)
     (prog2 (setq cc-imenu-objc-generic-expression-objc-base-index 9) "")
     "")				; -> index += 0
   (prog2 (setq cc-imenu-objc-generic-expression-proto-index 9) "")
   ;;
   ;; For Objective-C
   ;; Pick a token by (match-string 8 or 9)
   ;;
   "\\|\\("
   "^[-+][:" c-alnum "()*_<>\n\t ]*[;{]"        ; Methods
   "\\|"
   "^@interface[\t ]+[" c-alnum "_]+[\t ]*:"
   "\\|"
   "^@interface[\t ]+[" c-alnum "_]+[\t ]*([" c-alnum "_]+)"
   "\\|"
   ;; For NSObject, NSProxy and Object... They don't have super class.
   "^@interface[\t ]+[" c-alnum "_]+[\t ]*.*$"
   "\\|"
   "^@implementation[\t ]+[" c-alnum "_]+[\t ]*([" c-alnum "_]+)"
   "\\|"
   "^@implementation[\t ]+[" c-alnum "_]+"
   "\\|"
   "^@protocol[\t ]+[" c-alnum "_]+" "\\)")
  "Imenu generic expression for ObjC mode.  See `imenu-generic-expression'.")


;; Imenu support for objective-c uses functions.
(defsubst cc-imenu-objc-method-to-selector (method)
  "Return the objc selector style string of METHOD.
Example:
- perform: (SEL)aSelector withObject: object1 withObject: object2; /* METHOD */
=>
-perform:withObject:withObject:withObject: /* selector */"
  (let ((return "")			; String to be returned
	(p 0)				; Current scanning position in METHOD
	(pmax (length method))		;
	char				; Current scanning target
	(betweenparen 0)		; CHAR is in parentheses.
	argreq				; An argument is required.
	inargvar)			; position of CHAR is in an argument variable.
    (while (< p pmax)
      (setq char (aref method p)
	    p (1+ p))
      (cond
       ;; Is CHAR part of an objc token?
       ((and (not inargvar)   ; Ignore if CHAR is part of an argument variable.
	     (eq 0 betweenparen) ; Ignore if CHAR is in parentheses.
	     (or (and (<= ?a char) (<= char ?z))
		 (and (<= ?A char) (<= char ?Z))
		 (and (<= ?0 char) (<= char ?9))
		 (= ?_ char)))
	(if argreq
	    (setq inargvar t
		  argreq nil)
	  (setq return (concat return (char-to-string char)))))
       ;; Or a white space?
       ((and inargvar (or (eq ?\  char) (eq ?\n char))
	     (setq inargvar nil)))
       ;; Or a method separator?
       ;; If a method separator, the next token will be an argument variable.
       ((eq ?: char)
	(setq argreq t
	      return (concat return (char-to-string char))))
       ;; Or an open parentheses?
       ((eq ?\( char)
	(setq betweenparen (1+ betweenparen)))
       ;; Or a close parentheses?
       ((eq ?\) char)
	(setq betweenparen (1- betweenparen)))))
    return))

(defun cc-imenu-objc-remove-white-space  (str)
  "Remove all spaces and tabs from STR."
  (let ((return "")
	(p 0)
	(max (length str))
	char)
    (while (< p max)
      (setq char (aref str p))
      (setq p (1+ p))
      (if (or (= char ?\ ) (= char ?\t))
	  ()
	(setq return (concat return (char-to-string char)))))
    return))

(defun cc-imenu-objc-function ()
  "Imenu support for Objective C mode."
  (let (methodlist
	clist
	;;
	;; OBJC, Cnoreturn, Cgeneralfunc, Cproto are constants.
	;;
	;;                  *Warning for developers*
	;; These constants depend on `cc-imenu-c++-generic-expression'.
	;;
	(OBJC cc-imenu-objc-generic-expression-objc-base-index)
	;; Special case to match a line like `main() {}'
	(Cnoreturn cc-imenu-objc-generic-expression-noreturn-index)
	;; General function name regexp
	(Cgeneralfunc cc-imenu-objc-generic-expression-general-func-index)
	;; Special case for definitions using phony prototype macros like:
	(Cproto cc-imenu-objc-generic-expression-proto-index)
	langnum
	;;
	(classcount 0)
	toplist
	str
	str2
	(intflen (length "@interface"))
	(implen  (length "@implementation"))
	(prtlen  (length "@protocol"))
	(func
	 ;;
	 ;; Does this emacs have buffer-substring-no-properties?
	 ;;
	 (if (fboundp 'buffer-substring-no-properties)
	     'buffer-substring-no-properties
	   'buffer-substring)))
    (goto-char (point-max))
    ;;
    (while (re-search-backward cc-imenu-objc-generic-expression nil t)
      (when (not (c-literal-limits))
	(setq langnum (if (match-beginning OBJC)
			  OBJC
			(cond
			 ((match-beginning Cproto) Cproto)
			 ((match-beginning Cgeneralfunc) Cgeneralfunc)
			 ((match-beginning Cnoreturn) Cnoreturn))))
	(setq str (funcall func (match-beginning langnum) (match-end langnum)))
	;;
	(cond
	 ;;
	 ;; C
	 ;;
	 ((not (eq langnum OBJC))
	  (setq clist (cons (cons str (match-beginning langnum)) clist)))
	 ;;
	 ;; ObjC
	 ;;
	 ;; An instance Method
	 ((eq (aref str 0) ?-)
	  (setq str (concat "-" (cc-imenu-objc-method-to-selector str)))
	  (setq methodlist (cons (cons str
				       (match-beginning langnum))
				 methodlist)))
	 ;; A factory Method
	 ((eq (aref str 0) ?+)
	  (setq str (concat "+" (cc-imenu-objc-method-to-selector str)))
	  (setq methodlist (cons (cons str
				       (match-beginning langnum))
				 methodlist)))
	 ;; Interface or implementation or protocol
	 ((eq (aref str 0) ?@)
	  (setq classcount (1+ classcount))
	  (cond
	   ((and (> (length str) implen)
		 (string= (substring  str 0 implen) "@implementation"))
	    (setq str (substring str implen)
		  str2 "@implementation"))
	   ((string= (substring  str 0 intflen) "@interface")
	    (setq str (substring str intflen)
		  str2 "@interface"))
	   ((string= (substring  str 0 prtlen) "@protocol")
	    (setq str (substring str prtlen)
		  str2 "@protocol")))
	  (setq str (cc-imenu-objc-remove-white-space str))
	  (setq methodlist (cons (cons str2
				       (match-beginning langnum))
				 methodlist))
	  (setq toplist (cons (cons str methodlist) toplist)
		methodlist nil)))))

    ;; In this buffer, there is only one or zero @{interface|implementation|protocol}.
    (if (< classcount 2)
	(let ((classname (car (car toplist)))
	      (p (cdr (car (cdr (car toplist)))))
	      last)
	  (setq toplist (cons (cons classname p) (cdr (cdr (car toplist)))))
	  ;; Add C lang token
	  (if clist
	      (progn
		(setq last toplist)
		(while (cdr last)
		  (setq last (cdr last)))
		(setcdr last clist))))
      ;; Add C lang tokens as a sub menu
      (if clist
	  (setq toplist (cons (cons "C" clist) toplist))))
    ;;
    toplist
    ))

;(defvar cc-imenu-pike-generic-expression
;  ())
; FIXME: Please contribute one!

(defun cc-imenu-init (mode-generic-expression
		      &optional mode-create-index-function)
  (setq imenu-generic-expression mode-generic-expression
	imenu-case-fold-search nil)
  (when mode-create-index-function
    (setq imenu-create-index-function mode-create-index-function)))

\f
(cc-provide 'cc-menus)

;; Local Variables:
;; indent-tabs-mode: t
;; tab-width: 8
;; End:
;;; cc-menus.el ends here