fix: remove newlines in link descriptions

Currently, when an orgmode link has a newline in its description, it
is passed to the description of the Gemini link. Example:

```org
[[https://example.com][This is a link with a
newline to example.com]]
```

Which exports to:

```gmi
=> https://example.com This is a link with a
newline to example.com
```

This commit fixes this by replacing newlines with a simple space. The
new output is:

```gmi
=> https://example.com This is a link with a newline to example.com
```

It also fixes a compilation error on Emacs 30 by properly escaping
quotation marks.

Signed-off-by: Lucien Cartier-Tilet <lucien@phundrak.com>

ox-gemini.el

@@ -39,24 +39,37 @@
         (?f "To file"
             (lambda (a s v b)
               (org-gemini-export-to-file a s v b nil)))))
-  :translate-alist '((code . org-gemini-code-inline)
+  :translate-alist '((quote-block . org-gemini-quote-block)
+                     (code . org-gemini-code-inline)
+                     (export-block . org-gemini-export-block)
                      (paragraph . org-gemini-paragraph)
                      (headline . org-gemini-headline)
                      (link . org-gemini-link)
                      (section . org-gemini-section)
                      (src-block . org-gemini-code-block)
                      (item . org-gemini-item)
-                     (quote-block . org-gemini-quote-block)
-                     (template . org-gemini-template)))
+                     (template . org-gemini-template)
+                     (table . org-gemini-table)))
 
 (defun org-gemini-paragraph (_paragraph contents _info)
   "CONTENTS is the text of the paragraph."
   (concat (replace-regexp-in-string "\n" " " contents)
           "\n"))
 
-(defun org-gemini-item (_input contents _info)
-  "CONTENTS is the text of the individual item."
-  (format "* %s" contents))
+(defun org-gemini-item (item contents info)
+  "Generate a Gemtext item from the org CONTENTS.
+CONTENTS is the text of the individual item.
+ITEM is the parsed-org element with all properties."
+  (concat "* "
+          ;; vv Code from ox-md! vv
+	  (pcase (org-element-property :checkbox item)
+	    (`on "[X] ")
+	    (`trans "[-] ")
+	    (`off "[ ] "))
+	  (let ((tag (org-element-property :tag item)))
+	    (and tag (format "%s :: " (org-export-data tag info))))
+          ;; ^^ ^^
+          contents))
 
 (defun org-gemini-quote-block (_input contents _info)
   "CONTENTS is the text of the quote."
@@ -65,13 +78,16 @@
    (replace-regexp-in-string "\n\\'" "" contents)))
 
 (defun org-gemini-code-inline (input _contents info)
-  "INPUT is either a 'src-block' or 'example-block' element.  INFO is a plist."
+  "Generate an inline code in Gemtext from the parsed INPUT.
+INPUT is either a \\='src-block\\=' or \\='example-block\\='
+element.  INFO is a plist."
   ;; there's a bug here where there's a trailing space in the ``
   (format "`%s`" (org-export-format-code-default input info)))
 
 (defun org-gemini-code-block (src-block _contents info)
   "SRC-BLOCK is a codeblock.  INFO is a plist."
-  (let ((name (org-element-property :name src-block)))
+  (let ((name (or (caaar (org-element-property :caption src-block))
+                  (org-element-property :name src-block))))
     (org-remove-indentation
      (format "```%s\n%s```"
              (or name "")
@@ -80,7 +96,8 @@
 (defun org-gemini--describe-links (links _width info)
   "Describe links is the footer-portion of the link data.
 
-It's output just before each section.  LINKS is a list of each link.  INFO is a plist."
+It's output just before each section.  LINKS is a list of each link.
+INFO is a plist."
   (concat
    (mapconcat
     (lambda (link)
@@ -92,9 +109,10 @@ It's output just before each section.  LINKS is a list of each link.  INFO is a
                        (concat (file-name-sans-extension (org-element-property :path link)) ".gmi")
                      raw-path))
              (desc (org-element-contents link))
-             (anchor (org-export-data
-                      (or desc (org-element-property :raw-link link))
-                      info)))
+             (anchor (string-replace "\n" " "
+                                     (org-export-data
+                                      (or desc (org-element-property :raw-link link))
+                                      info))))
         (format "=> %s %s\n" (url-encode-url path) anchor)))
     links "")
    (when (car links)
@@ -116,7 +134,9 @@ Note: the footer with the actual links are handled in
   "Transcode a SECTION element from Org to GEMINI.
 CONTENTS is the contents of the section.  INFO is a plist holding
 contextual information."
-  (let ((links
+  ;; CONTENTS is nil when the section has no text but it has properties setted.
+  (let ((contents-str (or contents "")) ;; ensure that contents is a string.
+        (links
          (and (plist-get info :ascii-links-to-notes)
               ;; Take care of links in first section of the document.
               (not (org-element-lineage section '(headline)))
@@ -125,8 +145,8 @@ contextual information."
                (org-ascii--current-text-width section info)
                info))))
     (org-remove-indentation
-      (if (not (org-string-nw-p links)) contents
-        (concat (org-element-normalize-string contents) "\n\n" links))
+      (if (not (org-string-nw-p links)) contents-str
+        (concat (org-element-normalize-string contents-str) "\n\n" links))
       ;; Do not apply inner margin if parent headline is low level.
       (let ((headline (org-export-get-parent-headline section)))
         (if (or (not headline) (org-export-low-level-p headline info)) 0
@@ -136,7 +156,8 @@ contextual information."
     (element info _text-width &optional _underline _notags toc)
     "Build a title heading.
 
-ELEMENT is an org-element.  TOC is whether to show the table of contents.  INFO is unimportant."
+ELEMENT is an org-element.  TOC is whether to show the table of contents.
+INFO is unimportant."
   (let ((number (org-element-property :level element))
         (text
          (org-trim
@@ -196,8 +217,10 @@ holding contextual information."
                   (format "%c "
                           (nth (mod (1- low-level) (length bullets)) bullets))))
             (concat bullet title "\n" pre-blanks
-                    ;; Contents, indented by length of bullet.
-                    (org-ascii--indent-string body (length bullet))))
+                    ;; In Gemtext, text should not be indentend. Otherwise,
+                    ;; source code blocks, links, and other line types would not
+                    ;; be interpreted by clients because of the initial spacing.
+                    body))
         ;; Else: Standard headline.
         (concat title "\n" pre-blanks body)))))
 
@@ -274,6 +297,24 @@ Return output file name."
   (org-publish-org-to
    'gemini filename ".gmi" plist pub-dir))
 
+(defun org-gemini-export-block (export-block _contents _info)
+  "Transcode a EXPORT-BLOCK element from Org to Markdown.
+CONTENTS is nil.  INFO is a plist holding contextual information."
+  (when (member (org-element-property :type export-block)
+                '("GEMINI" "GMI" "GEMTEXT"))
+    (org-remove-indentation (org-element-property :value export-block))))
+
+(defun org-gemini-table (table contents info)
+  "Generate a Gemtext table from the parsed Org.
+Use the `org-ascii-table' but surrounded by backticks.
+Parameters: TABLE is the parsed org-element table.  CONTENTS is the text with
+properties.  INFO is a plist with export options."
+  (let ((name (or (caaar (org-element-property :caption table))
+                  (org-element-property :name table))))
+    (format "```%s\n%s\n```\n"
+            (or name "")
+            (org-ascii-table table contents info))))
+
 
 (provide 'ox-gemini)
 ;;; ox-gemini.el ends here