+ (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.
+Returns the url portion in the event that the display-string portion is empty."
+ (let* ((rest (string-trim (elt (split-string link-line "=>") 1)))
+ (idx (string-match "[ \t]" rest)))
+ (string-trim (if idx
+ (substring rest (+ idx 1))
+ rest))))
+
+(defun elpher-collapse-dot-sequences (filename)
+ "Collapse dot sequences in FILENAME.
+For instance, the filename /a/b/../c/./d will reduce to /a/c/d"
+ (let* ((path (split-string filename "/"))
+ (path-reversed-normalized
+ (seq-reduce (lambda (a b)
+ (cond ((and a (equal b "..") (cdr a)))
+ ((and (not a) (equal b "..")) a) ;leading .. are dropped
+ ((equal b ".") a)
+ (t (cons b a))))
+ path nil)))
+ (string-join (reverse path-reversed-normalized) "/")))
+
+(defun elpher-address-from-gemini-url (url)
+ "Extract address from URL with defaults as per gemini map files."
+ (let ((address (url-generic-parse-url url)))
+ (unless (and (url-type address) (not (url-fullness address))) ;avoid mangling mailto: urls
+ (setf (url-fullness address) t)
+ (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 (elpher-page-address elpher-current-page)))
+ (unless (string-prefix-p "/" (url-filename address)) ;deal with relative links
+ (setf (url-filename address)
+ (concat (file-name-directory
+ (url-filename (elpher-page-address elpher-current-page)))
+ (url-filename address)))))
+ (unless (url-type address)
+ (setf (url-type address) "gemini"))
+ (if (equal (url-type address) "gemini")
+ (setf (url-filename address)
+ (elpher-collapse-dot-sequences (url-filename address)))))
+ 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))
+ (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))))
+ (when display-string
+ (insert elpher-gemini-link-string)
+ (if type-map-entry
+ (let* ((face (elt type-map-entry 3))
+ (filtered-display-string (ansi-color-filter-apply display-string))
+ (page (elpher-make-page filtered-display-string address)))
+ (insert-text-button filtered-display-string
+ 'face face
+ 'elpher-page page
+ 'action #'elpher-click-link
+ 'follow-link t
+ 'help-echo #'elpher--page-button-help))
+ (insert (propertize display-string 'face 'elpher-unknown)))
+ (insert "\n"))))
+
+(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))))
+ (unless (display-graphic-p)
+ (insert (make-string level ?#) " "))
+ (insert (propertize header 'face
+ (pcase level
+ (1 'elpher-gemini-heading1)
+ (2 'elpher-gemini-heading2)
+ (3 'elpher-gemini-heading3)
+ (_ 'default)))
+ "\n"))))
+
+(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 "\\(^[ \t]*\\)\\(\*[ \t]\\)?" text-line)
+ (let* ((processed-text-line (if (match-string 2 text-line)
+ (concat
+ (replace-regexp-in-string "\*"
+ elpher-gemini-bullet-string
+ (match-string 0 text-line))
+ (substring text-line (match-end 0)))
+ text-line))
+ (fill-prefix (if (match-string 1 text-line)
+ (replace-regexp-in-string "\*" " " (match-string 0 text-line))
+ 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
+ (let ((preformatted nil))
+ (auto-fill-mode 1)
+ (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))))
+
+;; Finger page connection
+
+(defun elpher-get-finger-page (renderer &optional force-ipv4)
+ "Opens a finger connection to the current page address.
+The result is rendered using RENDERER. When the optional argument
+FORCE-IPV4 is non-nil, the IPv4 address returned by a DNS lookup will
+be used explicitly in making the connection."
+ (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))))
+ (port (let ((given-port (elpher-address-port address)))
+ (if (> given-port 0) given-port 79)))
+ (host (elpher-address-host address))
+ (selector-string-parts nil)
+ (proc (open-network-stream "elpher-process"
+ nil
+ (if force-ipv4 (dns-query host) host)
+ port
+ :type 'plain
+ :nowait t))
+ (timer (run-at-time elpher-connection-timeout
+ nil
+ (lambda ()
+ (pcase (process-status proc)
+ ('connect
+ (elpher-process-cleanup)
+ (unless force-ipv4
+ (message "Connection timed out. Retrying with IPv4 address.")
+ (elpher-get-finger-page renderer t))))))))
+ (setq elpher-network-timer timer)
+ (set-process-coding-system proc 'binary)
+ (set-process-filter proc
+ (lambda (_proc string)
+ (when timer
+ (cancel-timer timer)
+ (setq timer nil))
+ (setq selector-string-parts
+ (cons string selector-string-parts))))
+ (set-process-sentinel proc
+ (lambda (_proc event)
+ (condition-case _the-error
+ (cond
+ ((string-prefix-p "deleted" event))
+ ((string-prefix-p "open" event)
+ (let ((inhibit-eol-conversion t))
+ (process-send-string
+ proc
+ (concat user "\r\n"))))
+ (t
+ (when timer
+ (cancel-timer timer)
+ (setq timer nil))
+ (funcall renderer (apply #'concat
+ (reverse selector-string-parts)))
+ (elpher-restore-pos)))))))
+ (error
+ (elpher-network-error address the-error))))))
+
+
+;; Other URL page opening
+
+(defun elpher-get-other-url-page (renderer)
+ "Getter which attempts to open the URL specified by the current page (RENDERER must be nil)."
+ (when renderer
+ (elpher-visit-previous-page)
+ (error "Command not supported for general URLs"))
+ (let* ((address (elpher-page-address elpher-current-page))
+ (url (elpher-address-to-url address)))
+ (progn
+ (elpher-visit-previous-page) ; Do first in case of non-local exits.
+ (message "Opening URL...")
+ (if elpher-open-urls-with-eww
+ (browse-web url)
+ (browse-url url)))))
+
+;; 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))