;;; 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 'seq)
(require 'fg42/build/core)

(defun fg42/rss-map-items (file-and-props link)
  "Create a RSS item from the given org FILE with the give http LINK"
  (let* ((file (car file-and-props))
         (values (cadr file-and-props)))
    (format
     (concat
	  "  <item>\n"
	  "    <title>%s</title>\n"
	  "    <link>%s</link>\n"
	  "    <author>%s</author>\n"
	  "    <guid isPermaLink=\"false\">%s</guid>\n"
	  "    <pubDate>%s</pubDate>\n"
	  "    <description><![CDATA[%s]]></description>\n"
	  "  </item>\n")
     (cadr (assoc "TITLE" values))
     link
     (or
      (cadr (assoc "AUTHOR" values))
      fg42/build-author-name)
     link
     (or
      (cadr (assoc "DATE" values))
      (error "'DATE' is missing from '%s'" file))
     (or
      (cadr (assoc "DESC" values))
      (error "'DESC' is missing from '%s'" file)))))


(defun fg42/rss-create-item (post base-url)
  (fg42/rss-map-items
   (car (last post))
   (format "%s%s/%s"
           base-url
           fg42/build-docs-pages-dir
           ;; Path
           (nth 2 post))))

(defun fg42/rss-create (posts base-url dest)
  "Create a RSS xml file via POSTS for the give BASE-URL and save to DEST"
  (with-temp-file dest
    (insert
     (format
      (concat
       "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n"
       "<rss version=\"2.0\">\n"
       "<channel>\n"
       "  <title>%s</title>\n"
       "  <link>%s</link>\n"
       "  <description>%s</description>\n"
       "%s\n"
       "</channel>\n"
       "</rss>\n")
      fg42/build-docs-title
      base-url
      fg42/build-docs-desc
      (mapconcat
       (lambda (post)
         (fg42/rss-create-item post base-url))
       posts)))))


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