;;; srecode/mode.el --- Minor mode for managing and using SRecode templates  -*- lexical-binding: t; -*-

;; Copyright (C) 2008-2021 Free Software Foundation, Inc.

;; Author: Eric M. Ludlam <zappo@gnu.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:
;;
;; Minor mode for working with SRecode template files.
;;
;; Depends on Semantic for minor-mode convenience functions.

(require 'mode-local)
(require 'srecode)
(require 'srecode/insert)
(require 'srecode/find)
(require 'srecode/map)
(require 'semantic/decorate)
(require 'semantic/wisent)
(require 'semantic/senator)
(require 'semantic/wisent)

(eval-when-compile
  (require 'semantic/find))

;;; Code:

(defcustom srecode-minor-mode-hook nil
  "Hook run at the end of the function `srecode-minor-mode'."
  :group 'srecode
  :type 'hook)

;; We don't want to waste space.  There is a menu after all.
;;(add-to-list 'minor-mode-alist '(srecode-minor-mode ""))

(defvar srecode-prefix-key [(control ?c) ?/]
  "The common prefix key in srecode minor mode.")

(defvar srecode-prefix-map
  (let ((km (make-sparse-keymap)))
    ;; Basic template codes
    (define-key km "/" #'srecode-insert)
    (define-key km [insert] #'srecode-insert)
    (define-key km "." #'srecode-insert-again)
    (define-key km "E" #'srecode-edit)
    ;; Template indirect binding
    (let ((k ?a))
      (while (<= k ?z)
	(define-key km (format "%c" k) #'srecode-bind-insert)
	(setq k (1+ k))))
    km)
  "Keymap used behind the srecode prefix key in srecode minor mode.")

(defvar srecode-menu-bar
  (list
   "SRecoder"
   ["Insert Template"
    srecode-insert
    :active t
    :help "Insert a template by name."]
   ["Insert Template Again"
    srecode-insert-again
    :active t
    :help "Run the same template as last time again."]
     ["Edit Template"
    srecode-edit
    :active t
    :help "Edit a template for this language by name."]
   "---"
   '( "Insert ..." :filter srecode-minor-mode-templates-menu )
   '( "Generate ..." :filter srecode-minor-mode-generate-menu )
   "---"
   ["Customize..."
    (customize-group "srecode")
    :active t
    :help "Customize SRecode options"]
   (list
    "Debugging Tools..."
    ["Dump Template MAP"
     srecode-get-maps
     :active t
     :help "Calculate (if needed) and display the current template file map."]
    ["Dump Tables"
     srecode-dump-templates
     :active t
     :help "Dump the current template table."]
    ["Dump Dictionary"
     srecode-dictionary-dump
     :active t
     :help "Calculate and dump a dictionary for point."]
    ["Show Macro Help"
     srecode-macro-help
     :active t
     :help "Display the different types of macros available."]))
  "Menu for srecode minor mode.")

(defvar srecode-minor-menu nil
  "Menu keymap build from `srecode-menu-bar'.")

(defcustom srecode-takeover-INS-key nil
  "Use the insert key for inserting templates."
  :group 'srecode
  :type 'boolean)

(defvar srecode-mode-map
  (let ((km (make-sparse-keymap)))
    (define-key km srecode-prefix-key srecode-prefix-map)
    (easy-menu-define srecode-minor-menu km "Srecode Minor Mode Menu"
                      srecode-menu-bar)
    (when srecode-takeover-INS-key
      (define-key km [insert] srecode-prefix-map))
    km)
  "Keymap for srecode minor mode.")

;;;###autoload
(define-minor-mode srecode-minor-mode
  "Toggle srecode minor mode.

The minor mode can be turned on only if semantic feature is
available and the current buffer was set up for parsing.  Return
non-nil if the minor mode is enabled.

\\{srecode-mode-map}"
  :keymap srecode-mode-map
  ;; If we are turning things on, make sure we have templates for
  ;; this mode first.
  (if srecode-minor-mode
      (if (not (apply
		#'append
		(mapcar (lambda (map)
			  (srecode-map-entries-for-mode map major-mode))
			(srecode-get-maps))))
	  (setq srecode-minor-mode nil)
	;; Else, we have success, do stuff
	;; FIXME: Where are `cedet-m3-menu-do-hooks' nor `srecode-m3-items'?
	(when (fboundp 'srecode-m3-items)
	  (add-hook 'cedet-m3-menu-do-hooks #'srecode-m3-items nil t)))
    (when (fboundp 'srecode-m3-items)
      (remove-hook 'cedet-m3-menu-do-hooks #'srecode-m3-items t)))
  ;; Run hooks if we are turning this on.
  (when srecode-minor-mode
    (run-hooks 'srecode-minor-mode-hook))
  srecode-minor-mode)

;;;###autoload
(define-minor-mode global-srecode-minor-mode
  "Toggle global use of srecode minor mode."
  :global t :group 'srecode
  ;; Not needed because it's autoloaded instead.
  ;; :require 'srecode/mode
  (semantic-toggle-minor-mode-globally
   'srecode-minor-mode (if global-srecode-minor-mode 1 -1)))

;; Use the semantic minor mode magic stuff.
(semantic-add-minor-mode 'srecode-minor-mode "")

;;; Menu Filters
;;
(defun srecode-minor-mode-templates-menu (_menu-def)
  "Create a menu item of cascading filters active for this mode.
MENU-DEF is the menu to bind this into."
  ;; Doing this SEGVs Emacs on windows.
  ;;(srecode-load-tables-for-mode major-mode)

  (let* ((modetable (srecode-get-mode-table major-mode))
	 (subtab (when modetable (oref modetable tables)))
	 (context nil)
	 (active nil)
	 (ltab nil)
	 (temp nil)
	 (alltabs nil)
	 )
    (if (not subtab)
	;; No tables, show a "load the tables" option.
	(list (vector "Load Mode Tables..."
		      (lambda ()
			(interactive)
			(srecode-load-tables-for-mode major-mode))
		      ))
      ;; Build something
      (setq context (car-safe (srecode-calculate-context)))

      (while subtab
	(when (srecode-template-table-in-project-p (car subtab))
	  (setq ltab (oref (car subtab) templates))
	  (while ltab
	    (setq temp (car ltab))

	    ;; Do something with this template.

	    (let* ((ctxt (oref temp context))
		   (ctxtcons (assoc ctxt alltabs))
		   (bind (if (slot-boundp temp 'binding)
			     (oref temp binding)))
		   (name (eieio-object-name-string temp)))

	      (when (not ctxtcons)
		(if (string= context ctxt)
		    ;; If this context is not in the current list of contexts
		    ;; is equal to the current context, then manage the
		    ;; active list instead
		    (setq active
			  (setq ctxtcons (or active (cons ctxt nil))))
		  ;; This is not an active context, add it to alltabs.
		  (setq ctxtcons (cons ctxt nil))
		  (setq alltabs (cons ctxtcons alltabs))))

	      (let ((new (vector
			  (if bind
			      (concat name "   (" bind ")")
			    name)
			  (lambda () (interactive)
			    (srecode-insert (concat ctxt ":" name)))
			  t)))

		(push new (cdr ctxtcons))))

	    (setq ltab (cdr ltab))))
  	(setq subtab (cdr subtab)))

      ;; Now create the menu
      (easy-menu-filter-return
       (easy-menu-create-menu
	"Semantic Recoder Filters"
	(append (cdr active)
		alltabs)
	))
      )))

(defvar srecode-minor-mode-generators nil
  "List of code generators to be displayed in the srecoder menu.")

(defun srecode-minor-mode-generate-menu (_menu-def)
  "Create a menu item of cascading filters active for this mode.
MENU-DEF is the menu to bind this into."
  ;; Doing this SEGVs Emacs on windows.
  ;;(srecode-load-tables-for-mode major-mode)
  (let ((allgeneratorapps nil))

    (dolist (gen srecode-minor-mode-generators)
      (setq allgeneratorapps
	    (cons (vector (cdr gen) (car gen))
		  allgeneratorapps))
      (message "Adding %S to srecode menu" (car gen))
      )

    (easy-menu-filter-return
     (easy-menu-create-menu
      "Semantic Recoder Generate Filters"
      allgeneratorapps)))
  )

;;; Minor Mode commands
;;
(defun srecode-bind-insert ()
  "Bound insert for Srecode macros.
This command will insert whichever srecode template has a binding
to the current key."
  (interactive)
  (srecode-load-tables-for-mode major-mode)
  (let* ((k last-command-event)
	 (ctxt (srecode-calculate-context))
	 ;; Find the template with the binding K
	 (template (srecode-template-get-table-for-binding
		    (srecode-table) k ctxt)))
    ;; test it.
    (when (not template)
      (error "No template bound to %c" k))
    ;; insert
    (srecode-insert template)
    ))

(defun srecode-edit (template-name)
  "Switch to the template buffer for TEMPLATE-NAME.
Template is chosen based on the mode of the starting buffer."
  ;; @todo - Get a template stack from the last run template, and show
  ;; those too!
  (interactive (list (srecode-read-template-name
		      "Template Name: "
		      (car srecode-read-template-name-history))))
  (if (not (srecode-table))
      (error "No template table found for mode %s" major-mode))
    (let ((temp (srecode-template-get-table (srecode-table) template-name)))
      (if (not temp)
	  (error "No Template named %s" template-name))
      ;; We need a template specific table, since tables chain.
      (let ((tab (oref temp table))
	    (names nil)
	    )
	(find-file (oref tab file))
	(setq names (semantic-find-tags-by-name (oref temp object-name)
						(current-buffer)))
	(cond ((= (length names) 1)
	       (semantic-go-to-tag (car names))
	       (semantic-momentary-highlight-tag (car names)))
	      ((> (length names) 1)
	       (let* ((ctxt (semantic-find-tags-by-name (oref temp context)
							(current-buffer)))
		      (cls (semantic-find-tags-by-class 'context ctxt))
		      )
		 (while (and names
			     (< (semantic-tag-start (car names))
				(semantic-tag-start (car cls))))
		   (setq names (cdr names)))
		 (if names
		     (progn
		       (semantic-go-to-tag (car names))
		       (semantic-momentary-highlight-tag (car names)))
		   (error "Can't find template %s" template-name))
		 ))
	      (t (error "Can't find template %s" template-name)))
	)))

(defun srecode-add-code-generator (function name &optional binding)
  "Add the srecoder code generator FUNCTION with NAME to the menu.
Optional BINDING specifies the keybinding to use in the srecoder map.
BINDING should be a capital letter.  Lower case letters are reserved
for individual templates.
Optional MODE specifies a major mode this function applies to.
Do not specify a mode if this function could be applied to most
programming modes."
  ;; Update the menu generating part.
  (let ((remloop nil))
    (while (setq remloop (assoc function srecode-minor-mode-generators))
      (setq srecode-minor-mode-generators
	    (remove remloop srecode-minor-mode-generators))))

  (add-to-list 'srecode-minor-mode-generators
	       (cons function name))

  ;; Remove this function from any old bindings.
  (when binding
    (let ((oldkey (where-is-internal function
				      (list srecode-prefix-map)
				      t t t)))
      (if (or (not oldkey)
	      (and (= (length oldkey) 1)
		   (= (length binding) 1)
		   (= (aref oldkey 0) (aref binding 0))))
	  ;; Its the same.
	  nil
	;; Remove the old binding
	(define-key srecode-prefix-map oldkey nil)
	)))

  ;; Update Keybindings
  (let ((oldbinding (lookup-key srecode-prefix-map binding)))

    ;; During development, allow overrides.
    (when (and oldbinding
	       (not (eq oldbinding function))
	       (or (eq this-command 'eval-defun) (eq this-command 'checkdoc-eval-defun))
	       (y-or-n-p (format "Override old binding %s? " oldbinding)))
      (setq oldbinding nil))

    (if (not oldbinding)
	(define-key srecode-prefix-map binding function)
      (if (eq function oldbinding)
	  nil
	;; Not the same.
	(message "Conflict binding %S binding to srecode map."
		 binding))))
  )

;; Add default code generators:
(srecode-add-code-generator 'srecode-document-insert-comment "Comments" "C")
(srecode-add-code-generator 'srecode-insert-getset "Get/Set" "G")

(provide 'srecode/mode)

;; Local variables:
;; generated-autoload-file: "loaddefs.el"
;; generated-autoload-load-name: "srecode/mode"
;; End:

;;; srecode/mode.el ends here