wesnoth-mode.el

   1 ;; wesnoth-mode.el - A major mode for editing WML.
   2 ;; Copyright (C) 2006, 2007, 2008 Chris Mann
   3
   4 ;; This program is free software; you can redistribute it and/or
   5 ;; modify it under the terms of the GNU General Public License as
   6 ;; published by the Free Software Foundation; either version 2 of the
   7 ;; License, or (at your option) any later version.
   8
   9 ;; This program is distributed in the hope that it will be useful, but
  10 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
  11 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12 ;; General Public License for more details.
  13
  14 ;; You should have received a copy of the GNU General Public License
  15 ;; along with this program; see the file COPYING.  If not, write to the
  16 ;; Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
  17 ;; MA 02139, USA.
  18
  19 ;;; Description:
  20 ;;   wesnoth-mode is a major mode for Emacs which assists in the editing
  21 ;;   of Wesnoth Markup Language (WML) files.  Currently, this mode
  22 ;;   features syntax highlighting support, automatic indentation,
  23 ;;   tag-completion and preliminary support for syntax checking.
  24
  25 ;;; Usage:
  26 ;;   Add the following to your .emacs:
  27 ;;     (add-to-list 'load-path "path/to/wesnoth-mode")
  28 ;;     (autoload 'wesnoth-mode "wesnoth-mode" "Major mode for editing WML." t)
  29 ;;   Optionally adding:
  30 ;;     (add-to-list 'auto-mode-alist '("\\.cfg\\'" . wesnoth-mode))
  31 ;;   to automatically load wesnoth-mode for all files ending in '.cfg'.
  32
  33 ;;; Changes:
  34 ;; 1.2.2+git
  35 ;; * Added support for several new tags.
  36 ;; * Added menu for wesnoth-mode.
  37 ;; * Significant speed increase to indentation.
  38 ;; * Indentation can now be customised using `wesnoth-indent-preprocessor-bol'
  39 ;;   and `wesnoth-indent-savefile'; support for `wesnoth-indentation-function'
  40 ;;   has been removed.
  41 ;; * Trailing whitespace is no longer created when creating a second
  42 ;;   consectutive newline.
  43 ;; 1.2.2
  44 ;; * Added functions: `wesnoth-indent', `wesnoth-element-closing',
  45 ;;   `wesnoth-element', `wesnoth-element-opening',
  46 ;;   `wesnoth-insert-and-indent', `wesnoth-insert-missing-closing'.
  47 ;; * Renamed `wesnoth-indent-line-default', `wesnoth-indent-line-savefile' and
  48 ;;   `wesnoth-jump-backward', `wesnoth-jump-forward' to
  49 ;;   `wesnoth-indent-withtags-inline', `wesnoth-indent-default-inline' and
  50 ;;   `wesnoth-backward-tag', `wesnoth-forward-tag', respectively.
  51 ;; * Fixed a bug in indentation where content was needed between elements pairs
  52 ;;   for indentation to work.
  53 ;; * Fixed `wesnoth-newline-and-indent' ignoring the state of
  54 ;;   `wesnoth-auto-indent-flag'.
  55 ;; * Fixed `{...}' and `#endif' not font-locking correctly.
  56 ;; * Added indentation styles: `wesnoth-indent-default',
  57 ;;   `wesnoth-indent-withtags' which implement a a similar indentation
  58 ;;   style to the existing styles, however all preprocessor statements are
  59 ;;   indented to the first column.
  60 ;; * Added support for several new tags.
  61 ;; * Modified `wesnoth-newline' to behave more consistently.
  62 ;; * `wesnoth-jump-to-matching', `wesnoth-forward-tag', `wesnoth-backward-tag'
  63 ;;   now leaves point at the beginning (when moving backward) or end (when
  64 ;;   moving forward) of the match.
  65 ;; * `wesnoth-jump-to-matching' now attempts to find a target if necessary and
  66 ;;   will now work on preprocessor statements.  Will now warn if jump
  67 ;;   destination may not be correct (due to errors in WML structure).
  68 ;; * Indentation style is now determined by `wesnoth-indentation-function'.
  69 ;; * `wesnoth-check-structure' can now be applied over an active region and
  70 ;;   now checks preprocessor statements for correct nesting.
  71 ;; * `wesnoth-newline' and `wesnoth-newline-and-indent' can now be forced to
  72 ;;   perform indentation by providing a prefix argument.
  73 ;; * Indentation styles now leave point at the first non-whitespace character of
  74 ;;   the line.
  75 ;; * `wesnoth-check-tag-names' now reports on success.
  76 ;; * `wesnoth-insert-tag' is now able to insert tags around a region.
  77 ;; * `outline-minor-mode' now works on macro definitions.
  78 ;; 1.2.1
  79 ;; * Base indent now defaults to 4.
  80 ;; * Added support for #ifndef.
  81 \f
  82 (defconst wesnoth-mode-version "1.2.2+git"
  83   "The current version of wesnoth-mode.")
  84
  85 (defgroup wesnoth-mode nil "Wesnoth-mode access"
  86   :group 'languages
  87   :prefix "wesnoth-")
  88
  89 (defcustom wesnoth-indent-preprocessor-bol t
  90   "Style used to indent preprocessor statements.
  91 If non-nil, preprocessor statements are indented to the first
  92 column.  Otherwise, they are indented as tags."
  93   :type 'boolean
  94   :group 'wesnoth-mode)
  95
  96 (defcustom wesnoth-indent-savefile t
  97   "Style used to indent WML elements.
  98 If non-nil, attributes will be indented further than their
  99 containing element.  Otherwise, attributes will be indented at
 100 the same level."
 101   :type 'boolean
 102   :group 'wesnoth-mode)
 103
 104 (defcustom wesnoth-auto-indent-flag t
 105   "Whether to attempt tag indentation when a newline is created.
 106 If nil, no indentation will be attempted.  Otherwise, attempt to
 107 indent the line."
 108   :type 'boolean
 109   :group 'wesnoth-mode)
 110
 111 (defcustom wesnoth-base-indent 4
 112   "The number of columns to indent WML."
 113   :type 'integer
 114   :group 'wesnoth-mode)
 115
 116 (defconst wesnoth-preprocessor-regexp
 117   "#\\(?:define \\|e\\(?:lse\\|nd\\(?:\\(?:de\\|i\\)f\\)\\)\\|\\(?:ifn?\\|un\\)def \\)"
 118   "Regular expression to match all preprocessor statements.")
 119
 120 (defconst wesnoth-preprocessor-opening-regexp
 121   "#\\(?:define \\|else\\|ifdef \\|ifndef \\)"
 122   "Regular expression to match \"opening\" preprocessor statements.")
 123
 124 (defconst wesnoth-preprocessor-closing-regexp
 125   "#e\\(?:lse\\|nd\\(?:\\(?:de\\|i\\)f\\)\\)"
 126   "Regular expression to match \"closing\" preprocessor statements.")
 127
 128 (defvar wesnoth-mode-hook nil)
 129
 130 (defvar wesnoth-mode-map ()
 131   "Keymap used in wesnoth mode.")
 132 (unless wesnoth-mode-map
 133   (setq wesnoth-mode-map (make-sparse-keymap))
 134   (define-key wesnoth-mode-map "\C-\M-a" 'wesnoth-backward-tag)
 135   (define-key wesnoth-mode-map "\C-\M-e" 'wesnoth-forward-tag)
 136   (define-key wesnoth-mode-map "\C-c\C-m" 'wesnoth-jump-to-matching)
 137   (define-key wesnoth-mode-map "\C-cm" 'wesnoth-jump-to-matching)
 138   (define-key wesnoth-mode-map "\C-m" 'wesnoth-newline)
 139   (define-key wesnoth-mode-map "\C-j" 'wesnoth-newline-and-indent)
 140   (define-key wesnoth-mode-map "\C-c\C-c" 'wesnoth-check-structure)
 141   (define-key wesnoth-mode-map "\C-cc" 'wesnoth-check-structure)
 142   (define-key wesnoth-mode-map "\C-c\C-n" 'wesnoth-check-tag-names)
 143   (define-key wesnoth-mode-map "\C-cn" 'wesnoth-check-tag-names)
 144   (define-key wesnoth-mode-map "\C-c\C-e" 'wesnoth-insert-tag)
 145   (define-key wesnoth-mode-map "\C-ce" 'wesnoth-insert-tag)
 146   (define-key wesnoth-mode-map (kbd "C-c C-/") 'wesnoth-insert-missing-closing)
 147   (define-key wesnoth-mode-map (kbd "C-c /") 'wesnoth-insert-missing-closing)
 148   ;; Menu
 149   (define-key wesnoth-mode-map [menu-bar wesnoth]
 150     (cons "WML" (make-sparse-keymap "WML")))
 151   (define-key wesnoth-mode-map [menu-bar wesnoth insert-tag]
 152     '("Insert Tag" . wesnoth-insert-tag))
 153   (define-key wesnoth-mode-map [menu-bar wesnoth check-names]
 154     '("Check Tag Names" . wesnoth-check-tag-names))
 155   (define-key wesnoth-mode-map [menu-bar wesnoth check-structure]
 156     '("Check Structure" . wesnoth-check-structure))
 157   (define-key wesnoth-mode-map [menu-bar wesnoth jump-to-matching]
 158     '("Jump to Matching" . wesnoth-jump-to-matching))
 159   (define-key wesnoth-mode-map [menu-bar wesnoth insert-missing-closing]
 160     '("Insert Missing Tag" . wesnoth-insert-missing-closing)))
 161
 162 (defvar wesnoth-syntax-table
 163   (let ((wesnoth-syntax-table (make-syntax-table)))
 164     (modify-syntax-entry ?=  "." wesnoth-syntax-table)
 165     (modify-syntax-entry ?\_ "w" wesnoth-syntax-table)
 166     (modify-syntax-entry ?-  "_" wesnoth-syntax-table)
 167     (modify-syntax-entry ?.  "_" wesnoth-syntax-table)
 168     (modify-syntax-entry ?\n ">" wesnoth-syntax-table)
 169     (modify-syntax-entry ?\r ">" wesnoth-syntax-table)
 170     wesnoth-syntax-table)
 171   "Syntax table for wesnoth-mode.")
 172
 173 ;; Prevents automatic syntax-highlighting of elements which might be
 174 ;; pre-processor statements.
 175 (defvar wesnoth-syntactic-keywords
 176   (list
 177    '("^[\t ]*\\(#\\(?:define \\|e\\(?:lse\\|nd\\(?:\\(?:de\\|i\\)f\\)\\)\\|\\(?:ifn?\\|un\\)def \\)\\)" 1 "w")
 178    '("\\(#[\t ]*.*$\\)" 1 "<"))
 179   "Highlighting syntactic keywords within wesnoth-mode.")
 180
 181 (defvar wesnoth-font-lock-keywords
 182   (list
 183    '("\\(#\\(?:define\\|\\(?:ifn?\\|un\\)def\\)\\)"
 184      1 font-lock-preprocessor-face)
 185    '("\\(#\\(?:define\\|\\(?:ifn?\\|un\\)def\\)\\)[\t ]+\\(\\w+\\)"
 186      2 font-lock-function-name-face)
 187    '("\\(#e\\(?:lse\\|nd\\(?:\\(?:de\\|i\\)f\\)\\)\\)" . font-lock-preprocessor-face)
 188    '("\\({[@~]?\\(\\w\\|\\.\\|/\\|-\\)+}\\)"
 189      (1 font-lock-function-name-face))
 190    '("\\({\\(\\w\\|:\\)+\\|{[~@]?\\)"
 191      (1 font-lock-function-name-face))
 192    ;; Separated from above to support multi-line macro calls.
 193    '("}" .  font-lock-function-name-face)
 194    '("\\[[^]]+\\]" . font-lock-type-face)
 195    '("\\$\\w+" . font-lock-variable-name-face)
 196    '("\\(\\w+\\(\\,[\t ]*\\w+\\)*\\)="
 197      1 font-lock-variable-name-face))
 198   "Syntax highlighting for wesnoth-mode.")
 199
 200 (defvar wesnoth-tags-list
 201   (list
 202    "abilities" "about" "advances" "advancefrom" "ai" "allow_recruit" "and"
 203    "animation" "array" "attack" "attacks" "avoid" "binary_path" "bold"
 204    "campaign" "capture_village" "choose""clear_variable" "colour_adjust"
 205    "command" "deaths" "debug_message" "defend" "defends" "defense" "delay"
 206    "destination" "disallow_recruit" "do" "effect" "else" "end_turn" "endlevel"
 207    "entry" "era" "event" "expenses" "filter" "filter_adjacent_location"
 208    "filter_radius" "filter_second" "filter_vision" "format" "frame"
 209    "game_config" "generator" "gold" "have_unit" "header" "hide_unit" "if"
 210    "illuminated_time" "image" "img" "income" "italic" "item" "jump" "kill"
 211    "killed" "label" "language" "leader_goal" "main_map" "menu" "message"
 212    "mini_map" "missile_frame" "modifications" "modify_side" "modify_turns"
 213    "move" "move_unit_fake" "movement_costs" "movetype" "multiplayer"
 214    "multiplayer_side" "music" "not" "num_units" "object" "objectives"
 215    "objective" "observers" "option" "or" "panel" "part" "place_shroud"
 216    "position" "print" "protect_location" "protect_unit" "race" "random"
 217    "recall" "recalls" "recruit" "recruits" "redraw" "ref" "remove_shroud"
 218    "remove_unit_overlay" "removeitem" "replay" "replay_start" "resistance"
 219    "resolution" "results" "role" "save" "scenario" "scroll" "scroll_to"
 220    "scroll_to_unit" "section" "set_recruit" "set_variable" "side"
 221    "side_playing" "snapshot" "sound" "source" "specials" "statistics" "status"
 222    "stone" "store_gold" "store_locations" "store_starting_location"
 223    "store_unit" "story" "target" "team" "teleport" "teleport_anim" "terrain"
 224    "terrain_graphics" "test" "text_input" "textdomain" "theme" "then" "tile"
 225    "time" "time_area" "time_of_day" "topic" "toplevel" "trait" "turn"
 226    "tutorial" "unhide_unit" "unit" "unit_abilities" "unit_alignment"
 227    "unit_description" "unit_hp" "unit_image" "unit_level" "unit_moves"
 228    "unit_overlay" "unit_profile" "unit_status" "unit_traits" "unit_type"
 229    "unit_weapons" "unit_xp" "units" "unstone" "unstore_unit" "upkeep"
 230    "variable" "variables" "village" "villages" "while")
 231   "A list containing all tags which are available for use in WML.")
 232
 233 (defun wesnoth-element-closing ()
 234   "Return string to use for a closing element."
 235   (if wesnoth-indent-preprocessor-bol
 236       "^[ \t]*\\(\\[/.+\\]\\|#enddef\\)"
 237     (concat "^[ \t]*\\(\\[/.+\\]\\|\\("
 238             wesnoth-preprocessor-closing-regexp "\\)\\)")))
 239
 240 (defun wesnoth-element-opening ()
 241   "Return string to use for an opening element."
 242    (if wesnoth-indent-preprocessor-bol
 243        "^[ \t]*\\(\\[[^/]*?\\]\\|#define\\)"
 244    (concat "^[ \t]*\\(\\[[^/]*?\\]\\|\\("
 245            wesnoth-preprocessor-opening-regexp "\\)\\)")))
 246
 247 (defun wesnoth-element ()
 248   "Return string to use for an opening or closing element."
 249    (if wesnoth-indent-preprocessor-bol
 250        "^[\t ]*\\(\\[\\|#define\\|#enddef\\)"
 251      (concat "^[\t ]*\\(\\[\\|"
 252         wesnoth-preprocessor-regexp "\\)")))
 253 \f
 254 ;;; Insertion
 255 (defun wesnoth-insert-tag (tagname &optional start end)
 256   "Inserts the specified opening tag and it's matching closing tag.
 257 Both the opening and closing tags will be placed on their own
 258 lines with point positioned between them.  Completion of tags at
 259 the prompt uses `wesnoth-tags-list'.
 260
 261 TAGNAME is the name of the tag to be inserted.  If START and END
 262 are given, the tags will be inserted around the specified region.
 263 Enabling `transient-mark-mode' will cause `wesnoth-insert-tag' to
 264 insert opening and closing tags around the specified region."
 265   (interactive
 266    (list (completing-read "Tag: " wesnoth-tags-list nil nil)))
 267   (when (and (not (or start end)) transient-mark-mode mark-active)
 268     (setq start (region-beginning)
 269           end (copy-marker (region-end))))
 270     (if (and start end)
 271         (progn
 272           (goto-char start)
 273           (or (looking-at "^[\t ]*$")
 274               (open-line 1))
 275           (insert "[" tagname "]")
 276           (goto-char end)
 277           (or (looking-back "^[\t ]*$")
 278               (newline))
 279           (insert "[/" tagname "]\n")
 280           (setq end (point))  ;; New target for indent-region
 281           (indent-region start end))
 282       (or (looking-back "^[\t ]*$")
 283           (newline))
 284       (wesnoth-insert-and-indent "[" tagname "]")
 285       (wesnoth-insert-and-indent "\n")
 286       (save-excursion
 287         (wesnoth-insert-and-indent "\n[/" tagname "]"))))
 288
 289 (defun wesnoth-insert-missing-closing (&optional start end)
 290   "Insert the next expected closing element at point.
 291
 292 START and END define the region to check for missing closing
 293 elements.  If `transient-mark-mode' is enabled, the region
 294 specified will be used as START and END.  Otherwise, START and
 295 END will be the minimum and maximum positions of the buffer,
 296 respectively."
 297   (interactive)
 298   (if (and transient-mark-mode mark-active)
 299       (setq start (region-beginning)
 300             end (copy-marker (region-end)))
 301     (setq start (point-min)
 302           end (point-max)))
 303   (let ((element (wesnoth-check-structure start end)))
 304     (if element
 305       (if (string= element "Unexpected end of file")
 306           (message "%s" "Error: Expected end of file")
 307         (when (not (looking-at "^[\t ]*$"))
 308           (end-of-line)
 309           (wesnoth-newline))
 310         (insert element)
 311         (wesnoth-indent)
 312         (end-of-line))
 313       (error "%s" "Unable to find element to insert"))))
 314
 315 (defun wesnoth-insert-and-indent (&rest args)
 316   "Concatenate and insert the given string(s) before indenting."
 317   (insert (apply 'concat args))
 318   (wesnoth-indent)
 319   (end-of-line))
 320
 321 (defun wesnoth-newline (&optional indent)
 322   "Indent both the current line and the newline created.
 323 If `wesnoth-auto-indent-flag' is nil, indentation will not be
 324 performed."
 325   (interactive)
 326   (save-excursion
 327     (when (and (or wesnoth-auto-indent-flag indent)
 328                (not (looking-at "^[\t ]*$")))
 329       (wesnoth-indent)))
 330   (newline))
 331 \f
 332 ;;; Movement
 333 (defun wesnoth-forward-tag (repeat)
 334   "Move point to the end of the next tag.
 335 REPEAT is an optional numeric argument.  If REPEAT is non-nil,
 336 jump forward the specified number of tags."
 337   (interactive "p")
 338   (or repeat (setq repeat 1))
 339   (if (< repeat 0)
 340       (wesnoth-backward-tag (abs repeat))
 341     (let ((iterations 0))
 342       (while (< iterations repeat)
 343         (end-of-line)
 344         (search-forward-regexp
 345          (wesnoth-element-opening)
 346          (buffer-size) t)
 347         (setq iterations (1+ iterations))))
 348     (end-of-line)))
 349
 350 (defun wesnoth-backward-tag (repeat)
 351   "Move point to the beginning of the previous tag.
 352 REPEAT is an optional numeric argument.  If REPEAT is non-nil,
 353 jump backward the specified number of tags."
 354   (interactive "p")
 355   (or repeat (setq repeat 1))
 356   (if (< repeat 0)
 357       (wesnoth-forward-tag (abs repeat))
 358     (let ((iterations 0))
 359       (while (< iterations repeat)
 360         (beginning-of-line)
 361         (search-backward-regexp
 362          (wesnoth-element-opening)
 363          0 t)
 364         (unless (bobp)
 365           (search-forward-regexp "[^[:blank:]]")
 366           (backward-char))
 367         (setq iterations (1+ iterations))))))
 368
 369 (defun wesnoth-jump-to-matching ()
 370   "Jump point to the matching opening/closing tag.
 371 A tag must be on the same line as point for jumping to occur.
 372 Tag structure between the start and target positions must be
 373 consistent for jumping to occur."
 374   (interactive)
 375   (let ((open-tags 0)
 376         (search-started nil)
 377         (tag-position nil)
 378         (search-backward nil))
 379     (save-excursion
 380       (beginning-of-line)
 381       (if (looking-at
 382            (wesnoth-element))
 383           (when (looking-at (wesnoth-element-closing))
 384             (setq search-backward t))
 385         (if (wesnoth-wml-start-pos)
 386             (if (> (point) (wesnoth-wml-start-pos))
 387                 (search-backward-regexp
 388                  (wesnoth-element)
 389                  (point-min) t)
 390               (goto-char (point-min))
 391               (search-forward-regexp
 392                (wesnoth-element))
 393               (beginning-of-line))
 394           (error "%s" "Unable to locate tag to jump from")))
 395       (if search-backward
 396           (progn
 397             (end-of-line)
 398             (while (and
 399                     (or (< open-tags 0) (not search-started))
 400                     (search-backward-regexp
 401                      (wesnoth-element)
 402                      (point-min) t))
 403               (setq search-started t)
 404               (if (looking-at (wesnoth-element-opening))
 405                   (setq open-tags (1+ open-tags))
 406                 (when (looking-at (wesnoth-element-closing))
 407                     (setq open-tags (1- open-tags)))))
 408             (end-of-line)
 409             (search-backward-regexp "\\[\\|#"))
 410         (while (and
 411                 (or (> open-tags 0) (not search-started))
 412                 (search-forward-regexp
 413                  (wesnoth-element)
 414                  (point-max) t))
 415           (beginning-of-line)
 416           (setq search-started t)
 417           (if (looking-at (wesnoth-element-opening))
 418               (setq open-tags (1+ open-tags))
 419             (when (looking-at (wesnoth-element-closing))
 420                 (setq open-tags (1- open-tags))))
 421           (end-of-line))
 422         (end-of-line))
 423       (setq tag-position (point)))
 424     (and search-backward
 425          (end-of-line))
 426     (and (wesnoth-check-structure (min (point) tag-position)
 427                                   (max (point) tag-position))
 428          (message "%s" "Region concerning jump does not nest correctly; \
 429 target may not be correct"))
 430     (if (interactive-p)
 431         (goto-char tag-position)
 432       tag-position)))
 433 \f
 434 (defun wesnoth-wml-start-pos ()
 435   "Determine the position of `point' relative to where the actual WML begins.
 436 Return the likely starting position of the WML if it is found.
 437 Otherwise return nil."
 438   (save-excursion
 439     (goto-char (point-min))
 440     (when (search-forward-regexp
 441            (concat "^[\t ]*\\(\\[\\|" wesnoth-preprocessor-regexp "\\)")
 442          (buffer-size) t)
 443       (beginning-of-line)
 444       (point))))
 445
 446 (defun wesnoth-indent ()
 447   "Indent the current line as WML."
 448   (beginning-of-line)
 449   (if (or (not (wesnoth-wml-start-pos))
 450           (<= (point) (wesnoth-wml-start-pos))
 451           (nth 3 (syntax-ppss (point)))
 452           (and wesnoth-indent-preprocessor-bol
 453                (looking-at (concat "^[\t ]*" wesnoth-preprocessor-regexp))))
 454       (indent-line-to 0)
 455     (let ((cur-indent))
 456       (save-excursion
 457         (cond
 458          ;; Closing regexp
 459          ((looking-at (wesnoth-element-closing))
 460           (wesnoth-ensure-define-separate)
 461           ;; If closing preceded by closing, decrease indentation
 462           (when (and (looking-at (wesnoth-element-closing)))
 463             (setq cur-indent (- (current-indentation) wesnoth-base-indent))))
 464          ;; Opening regexp
 465          ((looking-at (wesnoth-element-opening))
 466           ;; Goto start-pos if unable to find target
 467           (wesnoth-ensure-define-separate)
 468           ;; If opening preceded by opening, increase indentation
 469           (when (or (looking-at (concat (wesnoth-element-opening)))
 470                     (not
 471                      (wesnoth-check-structure (wesnoth-wml-start-pos) (point))))
 472               (setq cur-indent (+ (current-indentation) wesnoth-base-indent))))
 473          ;; Not opening, not closing
 474          (t
 475           (wesnoth-ensure-define-separate)
 476           ;; Decrease indent if preceded by closing
 477           (if wesnoth-indent-savefile
 478               (and (looking-at (wesnoth-element-opening))
 479                    (setq cur-indent
 480                          (+ (current-indentation) wesnoth-base-indent)))
 481             (and (looking-at (wesnoth-element-closing))
 482                  (setq cur-indent (- (current-indentation)
 483                                      wesnoth-base-indent))))))
 484         ;; Indentation change unnecessary
 485         (unless cur-indent
 486           (setq cur-indent (current-indentation))))
 487       (and (< cur-indent 0) (setq cur-indent 0))
 488       (unless (and (not cur-indent) (= (current-indentation) cur-indent))
 489         (indent-line-to cur-indent))))
 490   (beginning-of-line)
 491   (search-forward-regexp "[\t ]*"))
 492
 493 (defun wesnoth-newline-and-indent (&optional indent)
 494   "Indent both the current line and the newline created.
 495 If `wesnoth-auto-indent-flag' is nil, indentation will not be
 496 performed."
 497   (interactive)
 498   (wesnoth-newline)
 499   (when (or wesnoth-auto-indent-flag indent)
 500     (wesnoth-indent)))
 501
 502 (defun wesnoth-within-define ()
 503   (interactive)
 504   (let ((upper)
 505         (lower))
 506     (save-excursion
 507       (end-of-line)
 508       (when (looking-back "^[\t ]*#enddef")
 509         (beginning-of-line))
 510       (search-backward-regexp
 511        "^[\t ]*\\(#define\\|#enddef\\)" (wesnoth-wml-start-pos) t)
 512       (if (looking-at "^[\t ]*#define")
 513           (setq upper (point)))
 514       (end-of-line)
 515       (search-forward-regexp
 516        "^[\t ]*#enddef" (point-max) t)
 517       (beginning-of-line)
 518       (if (looking-at "^[\t ]*#enddef")
 519           (setq lower (point))))
 520     (if (and upper (= upper (wesnoth-wml-start-pos)))
 521         nil
 522       (and upper lower))))
 523
 524 (defun wesnoth-ensure-define-separate ()
 525   "Ensure elements in #define blocks don't affect those outside."
 526   (if (and (not (wesnoth-within-define)) wesnoth-indent-preprocessor-bol)
 527       (progn
 528         (search-backward-regexp
 529          (wesnoth-element)
 530          (wesnoth-wml-start-pos) t)
 531         (while (and (wesnoth-within-define)
 532                     (not (= (point) (wesnoth-wml-start-pos))))
 533           (search-backward-regexp
 534            (wesnoth-element)
 535            (wesnoth-wml-start-pos) 'start-pos)))
 536     (search-backward-regexp
 537      (wesnoth-element)
 538      (wesnoth-wml-start-pos) 0)))
 539 \f
 540 ;;; WML checks
 541 (defun wesnoth-check-tag-names ()
 542   "Check the names of all tags in the buffer for correctness.
 543 If a tag is found which is not present in the list an error will
 544 be signalled and point will be moved to the corresponding
 545 position."
 546   (interactive)
 547   (let ((tag-position nil)
 548         (missing-tag-name nil))
 549     (save-excursion
 550       (goto-char (point-min))
 551       (while (and
 552               (search-forward-regexp "^[\t ]*\\[" (point-max) t)
 553               (not tag-position))
 554         (beginning-of-line)
 555         (when (looking-at "^[\t ]*\\[[/]?\\(\\w+\\)\\]")
 556           (unless (member (match-string-no-properties 1) wesnoth-tags-list)
 557             (setq tag-position (point))
 558             (setq missing-tag-name (match-string-no-properties 1))))
 559         (end-of-line)))
 560     (if tag-position
 561         (progn
 562           (goto-char tag-position)
 563           (end-of-line)
 564           (search-backward "[")
 565           (message "'%s' is not known to exist"
 566                    missing-tag-name))
 567       (message "%s" "No unknown tag names found."))))
 568
 569 (defun wesnoth-check-structure (&optional start end)
 570   "Check the buffer for correct nesting of elements.
 571 If a problem is found in the structure, point will be placed at
 572 the location which an element was expected and the expected
 573 element will be displayed in the mini-buffer.
 574
 575 START and END define the region to be checked.  If
 576 `transient-mark-mode' is enabled, the region specified will be
 577 checked.  Otherwise START and END will be the minimum and maximum
 578 positions of the buffer, respectively."
 579   (interactive)
 580   (unless (or start end)
 581     (if (and transient-mark-mode mark-active)
 582         (setq start (region-beginning)
 583               end (copy-marker (region-end)))
 584       (setq start (point-min)
 585             end (point-max))))
 586   (let ((unmatched-tag-list '())
 587         (error-position nil)
 588         (expected nil))
 589     (save-excursion
 590       (goto-char start)
 591       (while (and (search-forward-regexp (wesnoth-element) end t)
 592                   (not error-position))
 593         (beginning-of-line)
 594         (if (looking-at "^[\t ]*#\\(\\w+\\)")
 595             (let ((preprocessor-name (match-string-no-properties 1)))
 596               (cond
 597                ((member 't
 598                         (mapcar
 599                          '(lambda (preproc)
 600                             (string= preprocessor-name preproc))
 601                          '("define" "ifdef" "ifndef")))
 602                 (setq unmatched-tag-list
 603                       (cons preprocessor-name unmatched-tag-list)))
 604                ((string= preprocessor-name "else")
 605                 (unless (string-match "ifn?def" (car unmatched-tag-list))
 606                   (setq error-position (point))))
 607                ((string= preprocessor-name "endif")
 608                 (if (string-match "ifn?def" (car unmatched-tag-list))
 609                     (setq unmatched-tag-list (cdr unmatched-tag-list))
 610                   (setq error-position (point))))
 611                ((string= preprocessor-name "enddef")
 612                 (if (string= (car unmatched-tag-list) "define")
 613                     (setq unmatched-tag-list (cdr unmatched-tag-list))
 614                   (setq error-position (point))))))
 615           (if (looking-at "^[\t ]*\\[\\+?\\(\\w+\\)\\]")
 616               (setq unmatched-tag-list
 617                     (cons (match-string-no-properties 1)
 618                           unmatched-tag-list))
 619             (when (looking-at "^[\t ]*\\[/\\(\\w+\\)\\]")
 620               (if (string= (match-string-no-properties 1)
 621                            (car unmatched-tag-list))
 622                   (setq unmatched-tag-list (cdr unmatched-tag-list))
 623                 (setq error-position (point))))))
 624         (end-of-line)))
 625     (when unmatched-tag-list
 626       (cond ((string= (car unmatched-tag-list) "define")
 627              (setq expected "#enddef"))
 628             ((string-match "ifn?def" (car unmatched-tag-list))
 629              (setq expected "#endif"))
 630             ((not unmatched-tag-list)
 631              (setq expected "Unexpected end of file"))))
 632     (if (interactive-p)
 633         (if (not (or unmatched-tag-list error-position))
 634             (message "%s" "Structure appears consistent.")
 635           (and error-position
 636                (goto-char error-position))
 637           (if (string= expected "Unexpected end of file")
 638               (message "Error %s" expected)
 639             (message "Error: Expecting %s"
 640                      (or
 641                       expected
 642                       (concat " [/" (car unmatched-tag-list) "]")))))
 643       (when (or expected unmatched-tag-list)
 644         (or expected (concat "[/" (car unmatched-tag-list) "]"))))))
 645 \f
 646 ;;; wesnoth-mode
 647 (define-derived-mode wesnoth-mode fundamental-mode "wesnoth-mode"
 648   "Major mode for editing WML."
 649   (set-syntax-table wesnoth-syntax-table)
 650   (set (make-local-variable 'outline-regexp) "[\t ]*#define")
 651   (set (make-local-variable 'comment-start) "#")
 652   (set (make-local-variable 'indent-line-function) 'wesnoth-indent)
 653   (set (make-local-variable 'font-lock-defaults)
 654        '(wesnoth-font-lock-keywords
 655          nil t nil nil
 656          (font-lock-syntactic-keywords . wesnoth-syntactic-keywords)))
 657   (setq indent-tabs-mode nil)
 658   (setq mode-name "WML")
 659   (run-hooks 'wesnoth-mode-hook))
 660
 661 (provide 'wesnoth-mode)