;;; Buid --- The builder for FG42 -*- lexical-binding: t; -*-
;;
;; Copyright (c) 2010-2022 Sameer Rahmani & Contributors
;;
;; Author: Sameer Rahmani <lxsameer@gnu.org>
;; URL: https://gitlab.com/FG42/FG42
;; Version: 3.0.0
;;
;; This program 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.
;;
;; This program 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 thnis program.  If not, see <http://www.gnu.org/licenses/>.
;;
;;; Commentary:
;; Cubes are the building blocks of any `FG42' editor.  Each `cube' is a
;; unit which defines different abilities in a deterministic and idempotent
;; way.  Cubes are composable and a composition of cubes creates an editor.
;;
;;; Code:
(require 'ox-html)

(require 'cubes/all)
(require 'fg42/build/core)
(require 'fg42/build/utils)
(require 'fg42/build/ox-template)

(defvar cube-template (from-root "/docs/site/templates/cube.org"))
(defvar cubes-index-template (from-root "/docs/site/templates/cubes.org"))


(defun fg42/build-docs-for-cube (build-dir cube)
  "Build the given CUBE's doc in BUILD-DIR"
  (let* ((cubes-dir (expand-file-name "site/cubes/" build-dir))
         (props (symbol-plist cube))
         (docs  (plist-get props :docs))
         (cube-file (concat (expand-file-name (symbol-name cube) cubes-dir)
                            ".org")))
    (copy-template cube-template
                   cube-file
                   `((:title . ,(plist-get props :title))
                     (:docs . ,docs)))))


(defun fg42/build-docs-copy-base (build-dir)
  "Copy the base structure of the website to the BUILD-DIR."
  (copy-directory (from-docs "/pages")
                  (expand-file-name "site/pages" build-dir) nil t))


(defun fg42/build-prepare-docs (build-dir host)
  "Prepare the documents and the website in the given BUILD-DIR."
  (fg42/build-docs-copy-base build-dir)

  ;; Build the org files for each cube
  (message "Processing the docs for all the cubes")
  (mapcar (lambda (cube)
            (fg42/build-docs-for-cube build-dir cube))
          fg42/available-cubes)

  ;; Build the cubes list index file
  (message "Processing cubes index file")
  (copy-template cubes-index-template
                 (expand-file-name "site/cubes/index.org" build-dir)
                 (list
                  (cons :links (mapconcat (lambda (c)
                                            (format "- [[%s][%s]]\n"
                                                    ;; href
                                                    (format "%s/cubes/%s.html"  host c)
                                                    ;; title
                                                    (plist-get (symbol-plist c) :title)))
                                          (sort fg42/available-cubes 'string<))))))


(defun all-org-files ()
  "Return a list of all the org files in the orgs directory."

  (split-string
   (shell-command-to-string (format "find %s -iname \"*.org\"" org-directory))
   "\n" t))


(defun get-all-tags ()
  "Return a list of all the tags in the org files."
  (seq-reduce
   ;; all-tags is in (tags . tags->files) form
   (lambda (all-tags file)
     (if (get-file-global-props file "PAGE")
         ;; Ignore pages
         all-tags
       (with-temp-buffer
         (insert-file-contents file)
         (let ((tags (mapcar #'car (org-get-buffer-tags))))
           (seq-reduce
            (lambda (result tag)
              (let ((tag-list (car result))
                    (tag->file (cdr result)))
                (cons
                 ;; Tag list
                 (if (member tag tag-list) tag-list (sort (cons tag tag-list) 'string<))
                 ;; tag->file
                 (cons (cons tag
                             ;; Current value of the the given tag (all the files
                             ;; that contain that tag)
                             (append (list file) (cdr (assoc tag tag->file))))
                       tag->file))))
            tags
            all-tags)))))
   (all-org-files)
   '()))


(defun get-all-posts ()
  "Return all the post org files.
Not pages."
  (let ((files (all-org-files)))
    (seq-reduce
     (lambda (result file)
       (let ((is-page? (string= (get-file-global-props file "PAGE") "true")))
         (if (not is-page?)
             ;; It's a post
             (cons
              (list
               ;; This is not effecient since we parse the file
               ;; on each query, but who cares :D ?
               (->epoch (get-file-global-props file "DATE"))
               (get-file-global-props file "TITLE")
               (replace-regexp-in-string "\\.org" ".html"
                                         (file-name-nondirectory file)))
              result)
           result)))
     files
     '())))


(defun get-all-sorted-posts ()
  "Return all posts in sorted order."
  (sort
   (get-all-posts)
   (lambda (x y) (> (car x) (car y)))))


(defun latest-org-list (base-url)
  "Return a list of links (using BASE-URL) to the tags in org format."
  (let ((posts (get-all-sorted-posts)))
    (mapconcat
     (lambda (post)
       (format "    - [[%s/essays/%s][%s]]" base-url (nth 2 post) (nth 1 post)))
     posts
     "\n")))


(defun get-all-categories ()
  "Return all the categories of the org files."
  (seq-reduce
   ;; all-cats is in (cats . cat->files) form
   (lambda (all-cats file)
     (let ((is-page? (string= (get-file-global-props file "PAGE") "true"))
           (cat (get-file-global-props file "CATEGORY"))
           (cat-list (car all-cats))
           (cat->file (cdr all-cats)))

       (if (not is-page?)
           (cons
            ;; Category list
            (if (member cat cat-list) cat-list (sort (cons cat cat-list) 'string<))
            ;; cat->file
            (cons (cons cat
                        ;; Current value of the the given cat (all the files
                        ;; under that category)
                        (append (list file) (cdr (assoc cat cat->file))))
                  cat->file))
         all-cats)))
   (all-org-files)
   '()))


(defun category-org-list ()
  "Return a list of links to the categories in org format."
  (let ((categories (get-all-categories)))
    (mapconcat
     (lambda (cat)
       (let ((count (length (cdr (assoc cat (cdr categories))))))
         (format "    - [[./%s.html][%s(%s)]]" cat cat count)))
     (car categories)
     "\n")))


(defun tags-org-list ()
  "Return a list of links to the tags in org format."
  (let ((tags (get-all-tags)))
    (mapconcat
     (lambda (tag)
       (let ((count (length (cdr (assoc tag (cdr tags))))))
         (format "    - [[./%s.html][%s(%s)]]" tag tag count)))
     (car tags)
     "\n")))


(defun create-tag-pages (build-dir)
  "Create all the tag files in the BUILD-DIR."
  (let ((tags (get-all-tags)))
    (mapcar
     (lambda (tag)
       (let ((out (format "%s/site/tags/%s.org" build-dir (or tag "Uncategorized")))
             (files (cdr (assoc tag (cdr tags)))))
         (copy-template
          (from-docs "/templates/links_template.org")
          out
          (list
           (cons :links
                 (mapconcat
                  (lambda (file-pair)
                    (format "- [[file:..%s][%s]]"
                            (replace-regexp-in-string (regexp-quote (from-root "/build/site"))
                                                      ""
                                                      (cdr file-pair)
                                                      nil
                                                      'literal)
                            (get-file-global-props (cdr file-pair) "TITLE")))

                  (sort
                   (mapcar #'pair-file-with-date files)
                   (lambda (x y) (> (car x) (car y))))
                  "\n"))
           (cons :title (or tag "Uncategorized"))))))
     (car tags))))


(defun create-category-pages (build-dir)
  "Create all the category files in the BUILD-DIR."
  (let ((tags (get-all-categories)))
    (mapcar
     (lambda (tag)
       (let ((out (format "%s/site/categories/%s.org" build-dir (or tag "Uncategorized")))
             (files (cdr (assoc tag (cdr tags)))))
         (when (null tag)
           (message "[Error]: The following files are missig a category: %s"
                    (mapconcat
                     (lambda (x) (format "    %s\n" x))
                     (sort
                      (mapcar #'pair-file-with-date files)
                      (lambda (x y) (> (car x) (car y))))))
           (error "The above list of files are missing a category"))

         (copy-template
          (from-docs "/templates/links_template.org")
          out
          (list
           (cons :links
                 (mapconcat
                  (lambda (file-pair)
                    (format "- [[file:..%s][%s]]"
                            (replace-regexp-in-string (regexp-quote (from-root "/build/site"))
                                                      "" (cdr file-pair) nil 'literal)
                            (get-file-global-props (cdr file-pair) "TITLE")))
                  (sort
                   (mapcar #'pair-file-with-date files)
                   (lambda (x y) (> (car x) (car y))))
                  "\n"))
           (cons :title (or tag "Uncategorized"))))))
     (car tags))))


(defun fg42/build-docs (build-dir)
  "Build the documents and the website in the given BUILD-DIR."

  (let ((base-url (if (prod-p) "https://fg42.org" "http://localhost:3003"))
        (stage1-dir (expand-file-name "site" build-dir))
        (final-dir (expand-file-name "site-build" build-dir)))

    ;; Apply all the actions
    (mapcar (lambda (f)
              (funcall f build-dir base-url))
            fg42/build-docs-actions)

    ;; Copy the assets
    (copy-directory (from-docs "/assets")
                    (expand-file-name "assets" stage1-dir) nil t)

    ;; We will use the org-agenda to extract all the tags
    ;;; Set the dir containing org the org-files
    (setq org-directory (expand-file-name "site" build-dir))

    ;;; Discover all the org files
    (setq org-agenda-files (all-org-files))

    (setf user-full-name fg42/build-author-name)
    (setf user-mail-address fg42/build-author-email)

    ;; Disable default header links (top, next)
    (setf org-html-home/up-format "")
    (setf org-html-link-up "")
    (setf org-html-link-home "")
    (setf org-html-scripts "")

    (copy-template (from-docs "/config.org")
                   (expand-file-name "config.org" build-dir)
                   '())

    (message "Creating the main index file")
    (copy-template (from-docs "/templates/index.org")
                   (expand-file-name "site/index.org" build-dir)
                   `((:links . ,(latest-org-list base-url))
                     (:base-url . ,base-url)))

    (message "Creating categories")
    (copy-template (from-docs "/templates/categories.org")
                   (expand-file-name "site/categories/index.org" build-dir)
                   `((:links . ,(category-org-list))))

    (create-category-pages build-dir)

    (message "Creating tags")
    (copy-template (from-docs "/templates/tags.org")
                   (expand-file-name "site/tags/index.org" build-dir)
                   `((:links . ,(tags-org-list))))

    (create-tag-pages build-dir)

    (setq org-html-preamble #'preamble-fn)
    (setq org-html-htmlize-output-type nil)
    (setq org-latex-listings t)

    (setq org-publish-project-alist
          `(("fg42.org"
             :base-directory ,stage1-dir
             :root-directory ,stage1-dir
             :recursive t
             :base-extension "org"
             :publishing-directory ,final-dir
             ;; Exclude the blog archive index autogenerated below
             ;; Note that the regexp is relative to :base-directory
             ;; :exclude "^index.org"
             :section-numbers nil
             :with-author t
             :with-drawers t
             :html-format-drawer-function custom-drawer-format
             :with-properties t
             :with-tags t
             :with-timestamps t
             :with-toc nil
             :base-url ,base-url
             :html-link-home "/"
             :html-template ,(from-docs "/templates/blog.html")
             :html-page-preamble-template ,(from-docs "/templates/page-preamble.html")
             :html-post-preabmle-template ,(from-docs "/templates/post-preamble.html")
             :html-tags-template ,(from-docs "/templates/tags.html")
             :publishing-function org-html-publish-to-templated-html
             :auto-sitemap t
             :htmlized-source nil
             :sitemap-folders ignore
             :sitemap-style list
             :sitemap-title "FG42, The ultimate editor for true believers"
             :sitemap-filename "sitemap.inc"
             :sitemap-sort-files anti-chronologically
             :html-format-headline-function headline-format
             :makeindex nil)

            ("statics"
             :base-directory ,stage1-dir
             :base-extension "css\\|js\\|png\\|jpg\\|gif\\|pdf\\|svg"
             :publishing-directory ,final-dir
             :recursive t
             :publishing-function org-publish-attachment)
            ("build" :components ("fg42.org" "statics"))))

    (org-publish-project "build" t nil)
    (message "Build complete.")
    ))

(provide 'fg42/build/docs)
;;; docs.el ends here