;;; longtable.el --- AUCTeX style for `longtable.sty'.  -*- lexical-binding: t; -*-

;; Copyright (C) 2013--2020  Free Software Foundation, Inc.

;; Maintainer: auctex-devel@gnu.org
;; Author: Mosè Giordano <mose@gnu.org>
;; Keywords: tex

;; This file is part of AUCTeX.

;; AUCTeX 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, or (at your option)
;; any later version.

;; AUCTeX 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 AUCTeX; see the file COPYING.  If not, write to the Free
;; Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
;; 02110-1301, USA.

;;; Commentary:

;; This file adds support for `longtable.sty'.

;;; Code:

(require 'tex)
(require 'latex)

;; Silence the compiler:
(declare-function font-latex-add-keywords
                  "font-latex"
                  (keywords class))

(defvar LaTeX-longtable-skipping-regexp
  (regexp-opt '("[l]" "[r]" "[c]" ""))
  "Regexp matching between \\begin{longtable} and column specification.
For longtable environments only.")

(defun LaTeX-item-longtable (&optional suppress)
  "Insert line break macro on the last line and suitable number of &'s.
For longtable environments.  If SUPPRESS is non-nil, do not
insert line break macro."
  (unless suppress
    (save-excursion
      (end-of-line 0)
      (just-one-space)
      (TeX-insert-macro "\\")))
  (LaTeX-insert-ampersands
   LaTeX-longtable-skipping-regexp #'LaTeX-array-count-columns))

(defun LaTeX-env-longtable (environment)
  "Insert a longtable-like ENVIRONMENT with caption and label."
  (let* ((pos (completing-read (TeX-argument-prompt t nil "Position")
                               '(("l") ("r") ("c"))))
         (fmt (TeX-read-string "Format: " LaTeX-default-format))
         (caption (TeX-read-string "Caption: "))
         (short-caption (when (>= (length caption) LaTeX-short-caption-prompt-length)
                          (TeX-read-string "(Optional) Short caption: "))))
    (setq LaTeX-default-format fmt)
    (LaTeX-insert-environment environment
                              (concat
                               (unless (zerop (length pos))
                                 (concat LaTeX-optop pos LaTeX-optcl))
                               (concat TeX-grop fmt TeX-grcl)))
    ;; top caption -- do nothing if user skips caption
    (unless (zerop (length caption))
      ;; insert `\caption[short-caption]{caption':
      (insert TeX-esc "caption")
      (when (and short-caption (not (string= short-caption "")))
        (insert LaTeX-optop short-caption LaTeX-optcl))
      (insert TeX-grop caption)
      ;; ask for a label and insert it
      (LaTeX-label environment 'environment)
      ;; the longtable `\caption' is equivalent to a
      ;; `\multicolumn', so it needs a `\\' at the
      ;; end of the line.  Prior to that, add } to
      ;; close `\caption{'
      (insert TeX-grcl "\\\\")
      ;; fill the caption
      (when auto-fill-function (LaTeX-fill-paragraph))
      ;; Insert a new line and indent
      (LaTeX-newline)
      (indent-according-to-mode))
    ;; Insert suitable number of &'s, suppress line break
    (LaTeX-item-longtable t)))

(TeX-add-style-hook
 "longtable"
 (lambda ()
   (LaTeX-add-environments
    '("longtable" LaTeX-env-longtable))

   (TeX-add-symbols
    ;; Commands to end table rows
    '("endhead" 0)
    '("endfirsthead" 0)
    '("endfoot" 0)
    '("endlastfoot" 0)
    ;; Caption commands
    '("caption*" 1))

   ;; These parameters are set with \setlength
   (LaTeX-add-lengths
    "LTleft" "LTright" "LTpre" "LTpost" "LTcapwidth")

   ;; This parameter is set with \setcounter
   (LaTeX-add-counters "LTchunksize")

   ;; Use the enhanced table formatting.  Append to
   ;; `LaTeX-indent-environment-list' in order not to override custom settings.
   (add-to-list (make-local-variable 'LaTeX-indent-environment-list)
                '("longtable" LaTeX-indent-tabular) t)

   ;; Append longtable to `LaTeX-label-alist', in order not to override possible
   ;; custome values.
   (add-to-list 'LaTeX-label-alist '("longtable" . LaTeX-table-label) t)

   ;; Append longtable to `LaTeX-item-list' with `LaTeX-item-longtable'
   (add-to-list 'LaTeX-item-list '("longtable" . LaTeX-item-longtable) t)

   ;; Fontification
   (when (and (featurep 'font-latex)
              (eq TeX-install-font-lock 'font-latex-setup))
     ;; Actually, `\caption*{}' macro takes only one mandatory
     ;; argument, not an optional one, the following is a workaround
     ;; to fontify correctly also the standard `\caption[]{}' macro.
     (font-latex-add-keywords '(("caption" "*[{"))
                              'textual)))
 TeX-dialect)

;; `longtable.sty' has two options "errorshow" and "pausing", both for
;; debugging purposes.  We ignore them both in order to make package
;; loading faster in a buffer.
(defvar LaTeX-longtable-package-options nil
  "Package options for the longtable package.")

;; longtable.el ends here
