;;; pkg-writing.el --- Writing and blogging tools -*- lexical-binding: t -*-

;; Copyright (C) 2024 Cytrogen

;; This file contains:
;; - ox-hugo configuration for blog publishing
;; - YASnippet for text expansion
;; - Newsletter generation tools
;; - Writing-related utilities

;;; Commentary:

;; Tools and configurations specifically for writing, blogging, and content creation.
;; Includes Hugo integration and custom newsletter generation functions.

;;; Code:

;; Ox-Hugo Configuration
;; Blog publishing with Hugo
(unless (package-installed-p 'ox-hugo)
  (package-refresh-contents)
  (package-install 'ox-hugo))

(with-eval-after-load 'ox
  (require 'ox-hugo)
  (setq org-hugo-base-dir "~/Projects/blog"))

;; Universal Elisp Tags Filter
;; Support for Hexo-style block tags
(with-eval-after-load 'ox
  (defun my/org-export-hexo-universal-block (block backend info)
    (when (org-export-derived-backend-p backend 'md)
      (let* ((type (downcase (org-element-property :type block)))
         (content (org-export-data (org-element-contents block) info)))
	(format "{%% %s %%}\n%s{%% end%s %%}" type content type))))
  (add-to-list 'org-export-filter-special-block-functions 'my/org-export-hexo-universal-block))

;; YASnippet Configuration
;; Text expansion system
(unless (package-installed-p 'yasnippet)
  (package-install 'yasnippet))

(with-eval-after-load 'yasnippet
  (yas-global-mode 1)
  (yas-reload-all))

;; Newsletter Tools
;; Custom functions for newsletter generation
(defun my/slugify-title (title)
  "Convert title to anchor-compatible slug, similar to the nodejs script."
  (let ((slug title))
    ;; Remove 《》 brackets
    (setq slug (replace-regexp-in-string "《\\|》" "" slug))
    ;; Remove punctuation, keep Unicode letters, numbers, spaces, hyphens
    (setq slug (replace-regexp-in-string "[^[:alnum:]\\s-]" "" slug))
    ;; Replace spaces with hyphens  
    (setq slug (replace-regexp-in-string "\\s+" "-" slug))
    ;; Convert to lowercase
    (downcase slug)))

(defun my/generate-newsletter-toc ()
  "Generate TOC for newsletter, similar to the nodejs script."
  (interactive)
  (save-excursion
    (goto-char (point-min))
    
    ;; Find the end of details block
    (if (not (re-search-forward "#+END_details" nil t))
        (message "Error: Could not find #+END_details block")
      
      (let ((toc-sections '())
            (current-section nil))
        
        ;; Parse content after the details block
        (while (not (eobp))
          (beginning-of-line)
          (let ((line (thing-at-point 'line t)))
            (cond
             ;; Match H2 headings (exported as ## in markdown)
             ((string-match "^\\* \\(.*\\)$" line)
              (let ((section-title (match-string 1 line)))
                (setq current-section (list :title section-title :articles '()))
                (push current-section toc-sections)))
             
             ;; Match H4 headings with article links (exported as #### [...](url))
             ((and current-section 
                   (string-match "^\\*\\*\\*\\* \\[\\[.*?\\]\\[《\\(.*?\\)》\\]\\]" line))
              (let ((article-title (match-string 1 line)))
                (push article-title (plist-get current-section :articles))))))
          (forward-line 1))
        
        ;; Reverse to get correct order
        (setq toc-sections (reverse toc-sections))
        (dolist (section toc-sections)
          (setq section (plist-put section :articles (reverse (plist-get section :articles)))))
        
        ;; Generate TOC markdown
        (let ((toc-content "\n## 输入\n\n"))
          (dolist (section toc-sections)
            (let ((section-title (plist-get section :title))
                  (articles (plist-get section :articles)))
              (when articles
                (setq toc-content 
                      (concat toc-content 
                              (format "### %s\n\n" section-title)))
                (dolist (article articles)
                  (let ((display-title article)
                        (anchor (my/slugify-title article)))
                    (setq toc-content 
                          (concat toc-content 
                                  (format "- [%s](#%s)\n" display-title anchor))))
                (setq toc-content (concat toc-content "\n")))))
          
          ;; Find the details block and replace its content
          (goto-char (point-min))
          (if (re-search-forward "#+BEGIN_details 本期导读" nil t)
              (progn
                (forward-line 4) ; Skip PROPERTIES block
                (let ((start (point)))
                  (if (re-search-forward "#+END_details" nil t)
                      (progn
                        (beginning-of-line)
                        (delete-region start (point))
                        (insert toc-content)
                        (message "Newsletter TOC generated and inserted!"))
                    (message "Error: Could not find #+END_details"))))
            (message "Error: Could not find details block"))))))))

;; Writing Utilities
;; Additional writing helper functions
(defun my/insert-newsletter-toc ()
  "Deprecated: Use my/generate-newsletter-toc instead."
  (interactive)
  (message "Please use M-x my/generate-newsletter-toc instead."))

(provide 'pkg-writing)
;;; pkg-writing.el ends here