+ (insert content)
+ (elpher-restore-pos))
+ (elpher-with-clean-buffer
+ (insert "LOADING GEMINI... (use 'u' to cancel)\n"))
+ (setq elpher-gemini-redirect-chain nil)
+ (elpher-get-gemini-response address renderer))
+ (error
+ (elpher-network-error address the-error)))))
+
+(defun elpher-render-gemini (body &optional mime-type-string)
+ "Render gemini response BODY with rendering MIME-TYPE-STRING."
+ (if (not body)
+ t
+ (let* ((mime-type-string* (if (or (not mime-type-string)
+ (string-empty-p mime-type-string))
+ "text/gemini; charset=utf-8"
+ mime-type-string))
+ (mime-type-split (split-string mime-type-string* ";" t))
+ (mime-type (string-trim (car mime-type-split)))
+ (parameters (mapcar (lambda (s)
+ (let ((key-val (split-string s "=")))
+ (list (downcase (string-trim (car key-val)))
+ (downcase (string-trim (cadr key-val))))))
+ (cdr mime-type-split))))
+ (when (string-prefix-p "text/" mime-type)
+ (setq body (decode-coding-string
+ body
+ (if (assoc "charset" parameters)
+ (intern (cadr (assoc "charset" parameters)))
+ 'utf-8)))
+ (setq body (replace-regexp-in-string "\r" "" body)))
+ (pcase mime-type
+ ((or "text/gemini" "")
+ (elpher-render-gemini-map body parameters))
+ ("text/html"
+ (elpher-render-html body))
+ ((pred (string-prefix-p "text/"))
+ (elpher-render-gemini-plain-text body parameters))
+ ((pred (string-prefix-p "image/"))
+ (elpher-render-image body))
+ (_other
+ (elpher-render-download body))))))
+
+(defun elpher-gemini-get-link-url (link-line)
+ "Extract the url portion of LINK-LINE, a gemini map file link line.
+Returns nil in the event that the contents of the line following the
+=> prefix are empty."
+ (let ((l (split-string (substring link-line 2))))
+ (if l
+ (string-trim (elt l 0))
+ nil)))
+
+(defun elpher-gemini-get-link-display-string (link-line)
+ "Extract the display string portion of LINK-LINE, a gemini map file link line.
+Return nil if this portion is not provided."
+ (let* ((rest (string-trim (elt (split-string link-line "=>") 1)))
+ (idx (string-match "[ \t]" rest)))
+ (and idx
+ (elpher-color-filter-apply (string-trim (substring rest (+ idx 1)))))))
+
+(defun elpher-collapse-dot-sequences (filename)
+ "Collapse dot sequences in the (absolute) FILENAME.
+For instance, the filename \"/a/b/../c/./d\" will reduce to \"/a/c/d\""
+ (let* ((path (split-string filename "/" t))
+ (is-directory (string-match-p (rx (: (or "." ".." "/") line-end)) filename))
+ (path-reversed-normalized
+ (seq-reduce (lambda (a b)
+ (cond ((equal b "..") (cdr a))
+ ((equal b ".") a)
+ (t (cons b a))))
+ path nil))
+ (path-normalized (reverse path-reversed-normalized)))
+ (if path-normalized
+ (concat "/" (string-join path-normalized "/") (and is-directory "/"))
+ "/")))
+
+(defun elpher-address-from-gemini-url (url)
+ "Extract address from URL with defaults as per gemini map files.
+While there's obviously some redundancy here between this function and
+`elpher-address-from-url', gemini map file URLs require enough special
+treatment that a separate function is warranted."
+ (let ((address (url-generic-parse-url url))
+ (current-address (elpher-page-address elpher-current-page)))
+ (unless (and (url-type address) (not (url-fullness address))) ;avoid mangling mailto: urls
+ (if (url-host address) ;if there is an explicit host, filenames are absolute
+ (if (string-empty-p (url-filename address))
+ (setf (url-filename address) "/")) ;ensure empty filename is marked as absolute
+ (setf (url-host address) (url-host current-address))
+ (setf (url-fullness address) (url-host address)) ; set fullness to t if host is set
+ (setf (url-portspec address) (url-portspec current-address)) ; (url-port) too slow!
+ (unless (string-prefix-p "/" (url-filename address)) ;deal with relative links
+ (setf (url-filename address)
+ (concat (file-name-directory (url-filename current-address))
+ (url-filename address)))))
+ (when (url-host address)
+ (setf (url-host address) (puny-encode-domain (url-host address))))
+ (unless (url-type address)
+ (setf (url-type address) (url-type current-address)))
+ (when (equal (url-type address) "gemini")
+ (setf (url-filename address)
+ (elpher-collapse-dot-sequences (url-filename address)))))
+ (elpher-remove-redundant-ports address)))
+
+(defun elpher-gemini-insert-link (link-line)
+ "Insert link described by LINK-LINE into a text/gemini document."
+ (let ((url (elpher-gemini-get-link-url link-line)))
+ (when url
+ (let* ((given-display-string (elpher-gemini-get-link-display-string link-line))
+ (address (elpher-address-from-gemini-url url))
+ (type (if address (elpher-address-type address) nil))
+ (type-map-entry (cdr (assoc type elpher-type-map)))
+ (fill-prefix (make-string (+ 1 (length elpher-gemini-link-string)) ?\s)))
+ (when type-map-entry
+ (insert elpher-gemini-link-string)
+ (let* ((face (elt type-map-entry 3))
+ (display-string (or given-display-string
+ (elpher-address-to-iri address)))
+ (page (elpher-make-page display-string
+ address)))
+ (insert-text-button display-string
+ 'face face
+ 'elpher-page page
+ 'action #'elpher-click-link
+ 'follow-link t
+ 'help-echo #'elpher--page-button-help))
+ (newline))))))
+
+(defun elpher-gemini-insert-header (header-line)
+ "Insert header described by HEADER-LINE into a text/gemini document.
+The gemini map file line describing the header is given
+by HEADER-LINE."
+ (when (string-match "^\\(#+\\)[ \t]*" header-line)
+ (let* ((level (length (match-string 1 header-line)))
+ (header (substring header-line (match-end 0)))
+ (face (pcase level
+ (1 'elpher-gemini-heading1)
+ (2 'elpher-gemini-heading2)
+ (3 'elpher-gemini-heading3)
+ (_ 'default)))
+ (fill-column (if (display-graphic-p)
+ (/ (* fill-column
+ (font-get (font-spec :name (face-font 'default)) :size))
+ (font-get (font-spec :name (face-font face)) :size)) fill-column)))
+ (unless (display-graphic-p)
+ (insert (make-string level ?#) " "))
+ (insert (propertize header
+ 'face face
+ 'gemini-heading t
+ 'rear-nonsticky t))
+ (newline))))
+
+(defun elpher-gemini-insert-text (text-line)
+ "Insert a plain non-preformatted TEXT-LINE into a text/gemini document.
+This function uses Emacs' auto-fill to wrap text sensibly to a maximum
+width defined by `elpher-gemini-max-fill-width'."
+ (string-match
+ (rx (: line-start
+ (optional
+ (group (or (: "*" (+ (any " \t")))
+ (: ">" (* (any " \t"))))))))
+ text-line)
+ (let* ((line-prefix (match-string 1 text-line))
+ (processed-text-line
+ (if line-prefix
+ (cond ((string-prefix-p "*" line-prefix)
+ (concat
+ (replace-regexp-in-string "\\*"
+ elpher-gemini-bullet-string
+ (match-string 0 text-line))
+ (substring text-line (match-end 0))))
+ ((string-prefix-p ">" line-prefix)
+ (propertize text-line 'face 'elpher-gemini-quoted))
+ (t text-line))
+ text-line))
+ (fill-prefix (if line-prefix
+ (make-string (length (match-string 0 text-line)) ?\s)
+ nil)))
+ (insert (elpher-process-text-for-display processed-text-line))
+ (newline)))
+
+(defun elpher-render-gemini-map (data _parameters)
+ "Render DATA as a gemini map file, PARAMETERS is currently unused."
+ (elpher-with-clean-buffer
+ (auto-fill-mode 1)
+ (let ((preformatted nil)
+ (adaptive-fill-mode nil)) ;Prevent automatic setting of fill-prefix
+ (setq-local fill-column (min (window-width) elpher-gemini-max-fill-width))
+ (dolist (line (split-string data "\n"))
+ (cond
+ ((string-prefix-p "```" line) (setq preformatted (not preformatted)))
+ (preformatted (insert (elpher-process-text-for-display
+ (propertize line 'face 'elpher-gemini-preformatted))
+ "\n"))
+ ((string-prefix-p "=>" line)
+ (elpher-gemini-insert-link line))
+ ((string-prefix-p "#" line) (elpher-gemini-insert-header line))
+ (t (elpher-gemini-insert-text line)))))
+ (elpher-cache-content
+ (elpher-page-address elpher-current-page)
+ (buffer-string))))
+
+(defun elpher-render-gemini-plain-text (data _parameters)
+ "Render DATA as plain text file. PARAMETERS is currently unused."
+ (elpher-with-clean-buffer
+ (insert (elpher-process-text-for-display data))
+ (elpher-cache-content
+ (elpher-page-address elpher-current-page)
+ (buffer-string))))
+
+(defun elpher-build-current-imenu-index ()
+ "Build imenu index for current elpher buffer."
+ (save-excursion
+ (goto-char (point-min))
+ (let ((match nil)
+ (headers nil))
+ (while (setq match (text-property-search-forward 'gemini-heading t t))
+ (push (cons
+ (buffer-substring-no-properties (prop-match-beginning match)
+ (prop-match-end match))
+ (prop-match-beginning match))
+ headers))
+ (reverse headers))))
+
+;; Finger page connection
+
+(defun elpher-get-finger-page (renderer)
+ "Opens a finger connection to the current page address.
+The result is rendered using RENDERER."
+ (let* ((address (elpher-page-address elpher-current-page))
+ (content (elpher-get-cached-content address)))
+ (if (and content (funcall renderer nil))
+ (elpher-with-clean-buffer
+ (insert content)
+ (elpher-restore-pos))
+ (elpher-with-clean-buffer
+ (insert "LOADING... (use 'u' to cancel)\n"))
+ (condition-case the-error
+ (let* ((kill-buffer-query-functions nil)
+ (user (let ((filename (elpher-address-filename address)))
+ (if (> (length filename) 1)
+ (substring filename 1)
+ (elpher-address-user address)))))
+ (elpher-get-host-response address 79
+ (concat user "\r\n")
+ renderer))
+ (error
+ (elpher-network-error address the-error))))))
+
+
+;; Telnet page connection
+
+(defun elpher-get-telnet-page (renderer)
+ "Opens a telnet connection to the current page address (RENDERER must be nil)."
+ (when renderer
+ (elpher-visit-previous-page)
+ (error "Command not supported for telnet URLs"))
+ (let* ((address (elpher-page-address elpher-current-page))