;;; my-org-article.el --- Summary  -*- lexical-binding: t -*-

;;; Commentary:

;; EXAMPLE:
;; # -*- ispell-local-dictionary: "german" -*-

;;; Code:
(require 'ox-latex)

;;; Function Declarations
(defvar my-org-article-export-with-toc)
(defvar my-org-article-latex-default-packages-alist)
(defvar my-org-article-latex-packages-alist)
(defvar my-org-article-latex-compiler)
(defvar my-org-article-latex-default-class)
(defvar my-org-article-latex-default-class-options)
(defvar my-org-article-latex-header)
(defvar my-org-article-latex-header-extra)

(org-export-define-derived-backend 'article-latex 'latex

  :menu-entry
  '(?A "Export to LaTeX (Article)"
       ((?L "As LaTeX buffer" my-org-article-latex-export-as-latex)
	      (?l "As LaTeX file" my-org-article-latex-export-to-latex)
	      (?p "As PDF file" my-org-article-latex-export-to-pdf)
	      (?o "As PDF file and open"
	          (lambda (a s v b)
	            (if a (my-org-article-latex-export-to-pdf t s v b)
		            (org-open-file (my-org-article-latex-export-to-pdf nil s v b)))))))
  :options-alist
  '((:with-toc nil "toc" my-org-article-export-with-toc)
    (:latex-class "LATEX_CLASS" nil my-org-article-latex-default-class t)
    (:latex-class-options "LATEX_CLASS_OPTIONS" nil my-org-article-latex-default-class-options t)
    (:latex-header "LATEX_HEADER" nil my-org-article-latex-header newline)
    (:latex-header-extra "LATEX_HEADER_EXTRA" nil my-org-article-latex-header-extra newline)
    (:latex-compiler "LATEX_COMPILER" nil my-org-article-latex-compiler t))

  :translate-alist
  '((template . my-org-article-latex-template))
  )


;;; User Configurable Variables

(defgroup my-org-export-article nil
  "Options for exporting Org mode files."
  :tag "Org Export"
  :group 'org)

(defcustom my-org-article-export-with-toc nil
  "See `org-export-with-toc'."
  :group 'my-org-export-article
  :type '(choice
	  (const :tag "No Table of Contents" nil)
	  (const :tag "Full Table of Contents" t)
	  (integer :tag "TOC to level"))
  :safe (lambda (x)
	  (or (booleanp x)
	      (integerp x))))

;;;; Compilation

(defcustom my-org-articel-latex-compiler "lualatex"
  "See `org-latex-compiler'."
  :group 'my-org-export-article
  :type '(choice
	  (const :tag "pdfLaTeX" "pdflatex")
	  (const :tag "XeLaTeX"  "xelatex")
	  (const :tag "LuaLaTeX" "lualatex")
	  (const :tag "Unset" ""))
  :version "26.1"
  :package-version '(Org . "9.0"))

;;;; Preamble

(defcustom my-org-article-latex-class "koma-letter"
  "The default LaTeX class."
  :group 'my-org-export-article
  :type '(string :tag "LaTeX class"))

(defcustom my-org-article-latex-default-class-options "[enlargefirstpage]"
  "The default LaTeX class options."
  :group 'my-org-export-article
  :type '(string :tag "LaTeX class"))

(add-to-list 'org-latex-classes
             '("koma-letter" "\\documentclass{scrlttr2}"
               ("\\section{%s}" . "\\section*{%s}")
               ("\\subsection{%s}" . "\\subsection*{%s}")
               ("\\subsubsection{%s}" . "\\subsubsection*{%s}")
               ("\\paragraph{%s}" . "\\paragraph*{%s}")
               ("\\subparagraph{%s}" . "\\subparagraph*{%s}")))

(defcustom my-org-article-latex-header
  "\\setlength{\\parskip}{6pt}
\\setlength{\\parindent}{0pt}
\\setlength{\\textheight}{22.5cm}

\\newcommand{\\fromassociation}{<<fromassociation>>}
\\newcommand{\\fromname}{<<fromname>>}
\\setkomavar{fromname}{\\fromname}
\\newcommand{\\fromstreet}{<<fromstreet>>}
\\newcommand{\\fromplace}{<<fromplace>>}
\\setkomavar{fromaddress}{\\fromstreet, \\fromplace}
\\setkomavar{fromphone}{<<fromphone>>}
\\setkomavar{fromurl}{<<fromurl>>}
\\setkomavar{fromemail}{<<fromemail>>}
\\setkomavar{place}{<<place>>}
\\newcommand\\toassociation{<<toassociation>>}
\\newcommand\\toname{<<toname>>}
\\newcommand\\tostreet{<<tostreet>>}
\\newcommand\\toplace{<<toplace>>}
\\newcommand\\subject{<<subject>>}
\\newcommand\\subjectextra{<<subjectextra>>}

% adjust some spacings
\\makeatletter
\\@setplength{toaddrwidth}{10cm}
\\makeatother
"
  "Preamble options."
  :group 'my-org-export-article)

(defcustom my-org-article-latex-header-extra ""
  "Preamble extra options."
  :group 'my-org-export-article)

(defcustom my-org-article-latex-default-packages-alist
  '(("AUTO" "inputenc"  t ("pdflatex"))
    ("T1"   "fontenc"   t ("pdflatex"))
    (""     "graphicx"  t)
    (""     "grffile"   t)
    (""     "longtable" nil)
    (""     "wrapfig"   nil)
    (""     "rotating"  nil)
    ("normalem" "ulem"  t)
    (""     "amsmath"   t)
    (""     "textcomp"  t)
    (""     "amssymb"   t)
    (""     "capt-of"   nil)
    (""     "hyperref"  nil)
    ;; 
    ("ngerman" "babel"            nil)
    ("utf8"    "inputenc"         nil)
    (""        "scrlayer-scrpage" nil)
    )
  "See `org-latex-default-packages-alist'."
  :group 'my-org-export-article
  ;;:set 'org-set-packages-alist
  ;;:get 'org-get-packages-alist
  :version "26.1"
  :package-version '(Org . "8.3")
  :type '(repeat
	  (choice
	   (list :tag "options/package pair"
		 (string :tag "options")
		 (string :tag "package")
		 (boolean :tag "Snippet")
		 (choice
		  (const :tag "For all compilers" nil)
		  (repeat :tag "Allowed compiler" string)))
	   (string :tag "A line of LaTeX"))))

(defcustom my-org-article-latex-packages-alist nil
  "See `org-latex-packages-alist'."
  :group 'my-org-export-article
  ;;:set 'org-set-packages-alist
  ;;:get 'org-get-packages-alist
  :type '(repeat
	  (choice
	   (list :tag "options/package pair"
		 (string :tag "options")
		 (string :tag "package")
		 (boolean :tag "Snippet"))
	   (string :tag "A line of LaTeX"))))

;;;; Document

(defcustom my-org-letter-latex-opening
  "\\firsthead{
  \\begin{flushright}\\textsf{\\begin{tabular}{l}
  \\fromassociation \\\\ \\usekomavar{fromname} \\\\ \\fromstreet \\\\
  \\fromplace\\\\[3mm] \\usekomavar{fromphone} \\\\ \\usekomavar{fromemail}
  \\end{tabular}}\\end{flushright}
}
% Kopf und Fußzeile der Folgeseiten
\\defpagestyle{nextpage}{{} {} {\\textsf{\\parbox{\\hsize}{\\usekomavar{fromname}\\today\\ \\hrulefill\\ \\pagename~\\thepage}}}}
  {{} {} {}}
\\pagestyle{nextpage}

\\begin{letter}{Empfänger} % den Wert Empfänger nicht verändern
\\setkomavar{toname}{\\toassociation \\\\ \\toname}
\\setkomavar{toaddress}{\\tostreet \\\\ \\toplace}

\\setkomavar{subject}{\\subject \\\\ {\\normalfont \\subjectextra}}

\\opening{Sehr geehrter \\toname,}"
  "Letter opening."
  :group 'my-org-export-article)

(defcustom my-org-letter-latex-closing
  "\\closing{Freundliche Grüße,}"
  "Letter closing."
  :group 'my-org-export-article)


;;; Template

;;;###autoload
(defun my-org-article-latex-make-preamble (info &optional template snippet?)
  "See `org-latex-make-preamble'"
  (let* ((class (plist-get info :latex-class))
	 (class-template
	  (or template
	      (let* ((class-options (plist-get info :latex-class-options))
		     (header (nth 1 (assoc class (plist-get info :latex-classes)))))
		(and (stringp header)
		     (if (not class-options) header
		       (replace-regexp-in-string
			"^[ \t]*\\\\documentclass\\(\\(\\[[^]]*\\]\\)?\\)"
			class-options header t nil 1))))
	      (user-error "Unknown LaTeX class `%s'" class))))
    (org-latex-guess-polyglossia-language
     (org-latex-guess-babel-language
      (org-latex-guess-inputenc
       (org-element-normalize-string
	(org-splice-latex-header
	 class-template
	 (org-latex--remove-packages my-org-letter-latex-default-packages-alist info)
	 (org-latex--remove-packages my-org-letter-latex-packages-alist info)
	 snippet?
	 (mapconcat #'org-element-normalize-string
		 (list (s-replace-all
            (list (cons "<<fromassociation>>" (plist-get info :letter-from-association))
                  (cons "<<fromname>>" (plist-get info :letter-from-name))
                  (cons "<<fromstreet>>" (plist-get info :letter-from-street))
                  (cons "<<fromplace>>" (plist-get info :letter-from-place))
                  (cons "<<fromphone>>" (plist-get info :letter-from-phone))
                  (cons "<<fromurl>>" (plist-get info :letter-from-url))
                  (cons "<<fromemail>>" (plist-get info :letter-from-email))
                  (cons "<<toassociation>>" (plist-get info :letter-to-association))
                  (cons "<<toname>>" (plist-get info :letter-to-name))
                  (cons "<<tostreet>>" (plist-get info :letter-to-street))
                  (cons "<<toplace>>" (plist-get info :letter-to-place))
                  (cons "<<place>>" (plist-get info :letter-place))
                  (cons "<<date>>" (plist-get info :date))
                  (cons "<<subject>>" (string-replace "\n" "\\\\" (plist-get info :letter-subject)))
                  (cons "<<subjectextra>>" (string-replace "\n" "\\\\" (plist-get info :letter-subject-extra))))
            (plist-get info :latex-header))
			  (and (not snippet?)
			       (plist-get info :latex-header-extra)))
		    ""))))
      info)
     info)))

(defun my-org-article-latex-template (contents info)
  "See `org-latex-template'"
  (let ((title (org-export-data (plist-get info :title) info))
	(spec (org-latex--format-spec info)))
    (concat
     ;; Time-stamp.
     (and (plist-get info :time-stamp-file)
	  (format-time-string "%% Created %Y-%m-%d %a %H:%M\n"))
     ;; LaTeX compiler.
     (org-latex--insert-compiler info)
     ;; Document class and packages.
     (my-org-letter-latex-make-preamble info)
     ;; Possibly limit depth for headline numbering.
     (let ((sec-num (plist-get info :section-numbers)))
       (when (integerp sec-num)
	 (format "\\setcounter{secnumdepth}{%d}\n" sec-num)))
     ;; Author.
     (let ((author (and (plist-get info :with-author)
			(let ((auth (plist-get info :author)))
			  (and auth (org-export-data auth info)))))
	   (email (and (plist-get info :with-email)
		       (org-export-data (plist-get info :email) info))))
       (cond ((and author email (not (string= "" email)))
	      (format "\\author{%s\\thanks{%s}}\n" author email))
	     ((or author email) (format "\\author{%s}\n" (or author email)))))
     ;; Date.
     (let ((date (and (plist-get info :with-date) (org-export-get-date info))))
       (format "\\date{%s}\n" (org-export-data date info)))
     ;; Title and subtitle.
     (let* ((subtitle (plist-get info :subtitle))
	    (formatted-subtitle
	     (when subtitle
	       (format (plist-get info :latex-subtitle-format)
		       (org-export-data subtitle info))))
	    (separate (plist-get info :latex-subtitle-separate)))
       (concat
	(format "\\title{%s%s}\n" title
		(if separate "" (or formatted-subtitle "")))
	(when (and separate subtitle)
	  (concat formatted-subtitle "\n"))))
     ;; Hyperref options.
     (let ((template (plist-get info :latex-hyperref-template)))
       (and (stringp template)
            (format-spec template spec)))
     ;; Document start.
     "\\begin{document}\n\n"
     ;; Title command.
     (let* ((title-command (plist-get info :latex-title-command))
            (command (and (stringp title-command)
                          (format-spec title-command spec))))
       (org-element-normalize-string
	(cond ((not (plist-get info :with-title)) nil)
	      ((string= "" title) nil)
	      ((not (stringp command)) nil)
	      ((string-match "\\(?:[^%]\\|^\\)%s" command)
	       (format command title))
	      (t command))))
     ;; Table of contents.
     (let ((depth (plist-get info :with-toc)))
       (when depth
	 (concat (when (integerp depth)
		   (format "\\setcounter{tocdepth}{%d}\n" depth))
		 (plist-get info :latex-toc-command))))
     ;; Document's body.
     (concat (plist-get info :letter-opening) "\n")
     contents
     (concat (plist-get info :letter-closing) "\n")
     ;; attachments
     (let ((attachments (plist-get info :letter-attachment)))
       (unless (string-equal attachments "")
         (concat "\\vspace*{\\fill}\n"
                 "\\encl{" (string-replace "\n" "\\\\" attachments) "}\n")))
     "\\end{letter}\n"
     ;; Creator.
     (and (plist-get info :with-creator)
	  (concat (plist-get info :creator) "\n"))
     ;; Document end.
     "\\end{document}")))

;;;###autoload
(defun my-org-article-latex-export-to-latex
  (&optional async subtreep visible-only body-only ext-plist)
  "See `org-latex-export-to-latex'"
  (interactive)
  (let ((outfile (org-export-output-file-name ".tex" subtreep)))
    (org-export-to-file 'article-latex outfile
      async subtreep visible-only body-only ext-plist)))

;;;###autoload
(defun my-org-article-latex-export-to-pdf
  (&optional async subtreep visible-only body-only ext-plist)
  "See `org-latex-export-to-pdf'"
  (interactive)
  (let ((outfile (org-export-output-file-name ".tex" subtreep)))
    (org-export-to-file 'article-latex outfile
      async subtreep visible-only body-only ext-plist
      (lambda (file) (org-latex-compile file)))))

(provide 'my-org-article)
;;; my-org-article.el ends here