;;; mastodon-media.el --- Functions for inlining Mastodon media -*- lexical-binding: t -*- ;; Copyright (C) 2017-2019 Johnson Denen ;; Copyright (C) 2020-2022 Marty Hiatt ;; Author: Johnson Denen ;; Marty Hiatt ;; Maintainer: Marty Hiatt ;; Version: 1.0.0 ;; Homepage: https://codeberg.org/martianh/mastodon.el ;; This file is not part of GNU Emacs. ;; This file is part of mastodon.el. ;; mastodon.el 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. ;; mastodon.el 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 mastodon.el. If not, see . ;;; Commentary: ;; mastodon-media.el provides functions for inlining media. ;; Known bug gnutls -12 when trying to access images on some systems. ;; It looks like their may be a version mismatch between the encryption ;; required by the server and client. ;;; Code: (require 'url-cache) (autoload 'mastodon-tl--propertize-img-str-or-url "mastodon-tl") (defvar url-show-status) (defvar mastodon-tl--shr-image-map-replacement) (defgroup mastodon-media nil "Inline Mastadon media." :prefix "mastodon-media-" :group 'mastodon) (defcustom mastodon-media--avatar-height 20 "Height of the user avatar images (if shown)." :type 'integer) (defcustom mastodon-media--preview-max-height 250 "Max height of any media attachment preview to be shown in timelines." :type 'integer) (defcustom mastodon-media--enable-image-caching nil "Whether images should be cached." :type 'boolean) (defvar mastodon-media--generic-avatar-data (base64-decode-string "iVBORw0KGgoAAAANSUhEUgAAAGQAAABkCAIAAAD/gAIDAAAACXBIWXMAAAsTAAALEwEAmpwYAAAA B3RJTUUH4QUIFCg2lVD1hwAAABZ0RVh0Q29tbWVudABHZW5lcmljIGF2YXRhcsyCnMsAAAcGSURB VHja7dzdT1J/HAfwcw7EQzMKW0pGRMK4qdRZbdrs6aIRbt506V1b/AV1U2td9l9UXnmhW6vgwuko SbcOD/a0RB4CCRCRg0AIR4Hz8LvgN2cKCMI5wOH7uXBuugO+eH8+fM/3HIFpmoZAVVYIIABYAAtg ASyABbAAAcACWAALYAEsgAUIABbAAlgAC2ABLEAAsAAWwAJYAAtgAQKAxUjxm+R50DRN0zRFUf+8 kggCwzAMwwDrfyOSJGmattlsdrvd5XLlcrndnyoUir6+vpGRkZMnT/J4vIarwY26MaTAZLVap6en fT7f9vY2QRA7Ozv/vJJ8vkgk4vP5XV1dWq1Wq9VKpdIGkjUGi6IoFEWnp6ddLlcymSRJsvzv83g8 kUikUCi0Wq1Opzt16lS7YBEE8ebNG6PRiGHYoUwHyW7cuPHo0SOlUsl9LIIgXrx4Ybfb//79e7Qj CIXC3t7ex48fX7lyhctYBSkURTOZTC3H4fF4SqXy6dOnLHuxh0VR1PPnz2uX2uv17Nmzy5cvc21R StP0q1ev7HZ7XaQgCCJJ0u/3T0xMBINBrmGhKGo0Go88p0p5Wa1Wg8GQSqW4g0XT9NTUFIZhdT9y Npudn59nLVwIO7FyuVxVrRIqr1AoZDab2QkXG1hTU1PJZJKhg5MkOT8/HwqFuIBF07TP52MoVrvh YqLHG4BlsVi2t7cZfQiSJB0OBwudyDiWzWYjCILpR1lZWeECltPp3LeXwEQFg8FoNNryWPl8noVp ws6jgG1lgAWwuI914cIFPp/xnX6ZTCYSiVoeq7+/n4U/Q61Wy+Xylse6desWC8kaGBiQSCQtjyWR SGQyGY/HY+4hpFJpV1cXRwa8TqdjtBOHh4fVajVHsLRarVKpZChcUqn07t27LPQgS1gSiUSn04nF 4rofGYbh4eHhgYEBTq2ztFrtyMhI3ZtRo9GMjY2xEyv2sCQSiV6vV6lUdWzGzs7O8fHxwcFBDq7g 5XL5kydPent76+LV2dmp1+vv37/P5gqe7SvSDofj5cuXteydwjAslUr1ev2DBw9YPt1pwL0ODodj YmLCYrEcYZ8LhmGNRjM+Ps5yphqGBUFQKBQyGo0mk2l1dTWfz5MkSVFUPp8/+GSEQiEMw8eOHYNh uLu7e2hoaGxsjM05tbfYvpkNx/FQKBSJRCAI6unpwTBsbW0tmUwWbtc6mCMEQSAIOn78+Llz586f P9/T05PL5QKBgEKh4GyyCkZfvnwJhULhcHhzczOTyRRuYMtms/l8PpPJZDKZnZ2dvc9HIBCIxeIT J04Uvil87ejoOH36tEwm02g0V69evXjxIkewCkZer/fr16+/f/+OxWKlrvQQBEEQxL7dYQRBhEJh 0fNwBEHEYrFMJlOpVP39/RqNhgU1prAKTDMzMy6XKxqNJhIJptY+CHLmzBmZTHbp0qXbt2+rVKpW wtplWl5eDofDTF803Bs0tVrNKFmdsXAcn52dnZ2dDQaD7DAVJRsdHb1z507dT93rhoXj+MrKytzc 3NLSEnNNVyHZ2bNnr127NjQ0NDg4WEey+mDhOP7u3bu5ubkyI5z9iMnl8nv37o2OjgoEgmbBisVi r1+/ttlsjQ1UmYg9fPiwo6OjwVg4jn///v3Dhw/Ly8vNEKiiXhKJpK+vT6fT1d6S/FqkUBSdnJz0 +/1QsxZFUclkEkXReDxOkuT169dr8TpisnAcN5lMb9++ZfP+11pKIBAUdgpv3rx55BGGtIMUBEG5 XM7tdhsMhoWFhb3/S8UsVitK1curaqzV1dX379+3nNQ+r42NjSPsPlaH5fP5mnyiV+Ll9XonJyfD 4XC1XkhVDTgzM/Pz50+oxSubzX779u3z58/VLneQyqUMBsOnT5+acz1V7XoiHo9//PjRZDKl0+n6 Y3k8HrPZ3Gxr9Fq81tfXl5aWAoFA5cO+IqxIJFLYSIA4VARBuN3uxcXFyoc9v5IGNJvNVquVAw14 sBktFkt3d7dUKq3k5BGpJFYLCwucacCizZhIJCoJF3JorBYXF//8+QNxtAiCKFwiqKRvkEPnOoqi HGvAfeFKJBIVTnqkfKx+/PjBsbleKlwej6cmLI/H43A4OByr3XClUimn03louMphra2teb1eqA0q m836fL6tra0jYkUiEb/fz8k3waLhikQiXq+3/NtiSayNjY1fv35BbVP5fN7pdG5tbR0Fy+12c360 Hxzz5a8KI6V6EMMwzo/2fZ2YTqej0WgqlSoVLqRUDwYCAajNiqKoYDBYphOLY8ViscItVG1VJEmu r6+XeU8sjhWPxzc3N9sNiyAIDMOqS1YbDqwKx1YRrFQqxc7HJDRnpdPpUuEqgoVhWL0+i6hFz6tL ja3iM4u1zw1qwhlfJihI0bfCNhxYe4NSqg3/A862hQAbrdtHAAAAAElFTkSuQmCC") "The PNG data for a generic 100x100 avatar.") (defvar mastodon-media--generic-broken-image-data (base64-decode-string "iVBORw0KGgoAAAANSUhEUgAAAMgAAADICAYAAACtWK6eAAAACXBIWXMAAAsTAAALEwEAmpwYAAAA B3RJTUUH4QUIFQUVFt+0LQAAABZ0RVh0Q29tbWVudABHZW5lcmljIGF2YXRhcsyCnMsAAAdoSURB VHja7d1NSFRrAIfx//iB6ZDSMJYVkWEk0ceYFUkkhhQlEUhEg0FlC1eBoRTUwlbRok0TgRQURZAE FgpjJmFajpK4kggxpXHRQEGWUJZizpy7uPfC5eKiV+dD5zw/mN05jrxnnjnfcxyWZVkCMKc0SXI4 HIwEMIcUhgAgEIBAAAIBCAQgEIBAAAIBCAQgEAAEAhAIQCAAgQAEAhAIQCAAgQA2kBaNP8Jt7ViM onErOWsQgEAAAgEIBCAQgEAAAgEIBCAQgEAAEAhAIACBAAQCEAhAIACBAAQCEAhAIAAIBCAQgEAA AgEIBCAQgEAAAgEIBACBAAQCEAhAIACBAAQCEAhAIACBAAQCgEAAAgEIBCAQgECAxSyNIYitz58/ a3BwUIODgxoZGVEoFFIoFNK3b980NTWlX79+SZIyMzOVlZWlVatWae3atSooKJDH49HOnTvl8XiU ksJ3WSI4LMuyHA7Hgv6IZVmM5D8mJyf1/PlzdXZ2qrOzU8FgcMF/0+126+DBg6qqqlJFRYXS0vhe +6MP9wI/1wQSJeFwWH6/X01NTWpra9PU1FTM3isvL0/nz5/XuXPntHz5ciqIcSCy/v50L+hlV+Pj 49a1a9esdevWLXgMTV8ul8u6c+eOFYlELMwtKmNNIOa+fv1qXbp0yXI6nXEP4/+v0tJS6+PHj9RA IIk3PT1tXb161crOzk54GP995ebmWt3d3RRBIInj9/utgoKCRRXGf18ZGRmW3++niigHwk56PHf4 Yiw9PV0dHR0qLy9nD52jWAQylxUrVmhgYEAbN24kkCgsM84+JZmJiQmdPn1akUiEweBE4eL/NsrN zVVZWZlKSkpUWFioTZs2yeVyKTs7W7Ozs5qYmNDExITev3+v/v5+9fX1qb+/f8FjevPmTdXW1rIG IZDFN9gbNmyQ1+uV1+uVx+MxXlAjIyNqbGzU3bt39fPnz3n9vytXrlQwGJTT6SQQThQm/ohIamqq VVlZaXV1dUXtPT98+GCVlZXNe7n4fD6OYnGYN7GDnZ6ebtXU1FhjY2Mxed9IJGLV19fPa7kUFRUR CIEkZrAdDod15syZmIXxf7W1tfNaNqOjowSygBdHseZh7969GhgY0IMHD5Sfnx+X97xx44Z2795t PF93dzcLjMO88TvHcP/+ffX19WnXrl3xXVApKbp9+7bxfSFv3rxhwRFI7B07dkxDQ0Oqrq5O2P9Q XFysffv2Gc0zOjrKwiOQ2Hv69Kny8vIS/n8cP37caPqxsTEWHoHYa//HxPfv3xk0ArGP1atXG03/ 7z3vIBBbyM3NNZo+KyuLQSMQ+5icnDSaPicnh0EjEPsYHh42mp7L3gnEVnp6eoymLyoqYtAIxD4e PXpkNP3+/fsZtAXgcvclpL29XUeOHPnj6Z1Op8bHx7Vs2TJ7fri5o9A+ZmZmdPHiRaN5vF6vbeNg E8tmGhoaNDQ0ZPTteeHCBQaOQJLfkydPdP36daN5Tp48qc2bNzN47IMkt9evX+vw4cOanp7+43ly cnI0PDy8KK4dYx8EMRMIBHT06FGjOCTJ5/PZPg42sZJce3u7Dh06pB8/fhjNV11dndBL8tnEYhMr 5lpaWuT1evX792+j+YqLixUIBLj+ik2s5NXc3KwTJ04Yx5Gfn69nz54RB5tYyaupqUlVVVWanZ01 ms/tdqujo4P9DgJJXg8fPtSpU6cUDoeN43j58qUKCwsZRAJJTvfu3dPZs2eNf0/X7Xarq6tL27dv ZxAJJDn5fD7V1NQYx7FmzRq9evVK27ZtYxAJJDk1NDSorq7O+ChgQUGBent7tWXLFgYxxniecILU 1dXJ5/MZz7d161a9ePHC+N50sAZZMq5cuTKvOEpKStTT00McccSJwji7devWvJ7bceDAAbW2ttr6 cQbGH26eD7K0BAIBlZeXG5/nqKioUEtLizIyMhhEAklOX758kcfj0adPn4zXHG1tbcSRoEDYB4mT y5cvG8exZ88etba2Egf7IMnt7du32rFjh9G5jvz8fA0MDBj/UBxYgyw5jY2NRnGkpqaqubmZOBYB AomxmZkZPX782Gie+vr6uD9/BGxiJURvb69KS0v/ePrMzEyFQiG5XC4Gj02s5BcIBIymr6ysJA42 sezj3bt3RtObPv8DBLKkBYNBo+m5r4NAbCUUChlNv379egaNQOzD9FdJ2P8gEFsxfQQaFyMuLhzm jfUAG45tOBw2fhY6ojP2rEGWwiqdONjEAggEIBCAQAACAUAgAIEA0cIPx8UYJ1FZgwAEAhAIAAIB CAQgEIBAAAIBFiNOFMaY6V1tnFhkDQIQCEAgAIEABAKAQAACAQgEIBCAQAACAQgEIBCAQABIXO4e c1y+zhoEIBCAQAAQCEAgAIEABAIQCEAgAIEABAIQCEAgAAgEIBCAQAACAQgEIBCAQAACAQgEAIEA BAIQCEAgAIEABAIsJVH58WqHw8FIgjUIQCAACAQgEIBAAAIBCAQgEIBAAAIBCAQgEAAEAhAIQCBA fKRJkmVZjAQwh78A6vCRWJE8K+8AAAAASUVORK5CYII=") "The PNG data for a generic 200x200 \"broken image\" view.") (defun mastodon-media--process-image-response (status-plist marker image-options region-length url) "Callback function processing the url retrieve response for URL. STATUS-PLIST is the usual plist of status events as per `url-retrieve'. IMAGE-OPTIONS are the precomputed options to apply to the image. MARKER is the marker to where the response should be visible. REGION-LENGTH is the length of the region that should be replaced with the image." (when (marker-buffer marker) ; if buffer hasn't been killed (let ((url-buffer (current-buffer)) (is-error-response-p (eq :error (car status-plist)))) (unwind-protect (let* ((data (unless is-error-response-p (goto-char (point-min)) (search-forward "\n\n") (buffer-substring (point) (point-max)))) (image (when data (apply #'create-image data (if (version< emacs-version "27.1") (when image-options 'imagemagick) nil) ; inbuilt scaling in 27.1 t image-options)))) (when mastodon-media--enable-image-caching (unless (url-is-cached url) ; cache if not already cached (url-store-in-cache url-buffer))) (with-current-buffer (marker-buffer marker) ;; Save narrowing in our buffer (let ((inhibit-read-only t)) (save-restriction (widen) (put-text-property marker (+ marker region-length) 'media-state 'loaded) (when image ;; We only set the image to display if we could load ;; it; we already have set a default image when we ;; added the tag. (put-text-property marker (+ marker region-length) 'display image)) ;; We are done with the marker; release it: (set-marker marker nil))) (kill-buffer url-buffer))))))) (defun mastodon-media--load-image-from-url (url media-type start region-length) "Take a URL and MEDIA-TYPE and load the image asynchronously. MEDIA-TYPE is a symbol and either `avatar' or `media-link.' START is the position where we start loading the image. REGION-LENGTH is the range from start to propertize." (let ((image-options (when (or (image-type-available-p 'imagemagick) (image-transforms-p)) ; inbuilt scaling in 27.1 (cond ((eq media-type 'avatar) `(:height ,mastodon-media--avatar-height)) ((eq media-type 'media-link) `(:max-height ,mastodon-media--preview-max-height)))))) (let ((buffer (current-buffer)) (marker (copy-marker start)) (url-show-status nil)) ; stop url.el from spamming us about connecting (condition-case nil ;; catch any errors in url-retrieve so as to not abort ;; whatever called us (if (and mastodon-media--enable-image-caching (url-is-cached url)) ;; if image url is cached, decompress and use it (with-current-buffer (url-fetch-from-cache url) (set-buffer-multibyte nil) (goto-char (point-min)) (zlib-decompress-region (goto-char (search-forward "\n\n")) (point-max)) (mastodon-media--process-image-response nil marker image-options region-length url)) ;; else fetch as usual and process-image-response will cache it (url-retrieve url #'mastodon-media--process-image-response (list marker image-options region-length url))) (error (with-current-buffer buffer ;; TODO: Consider adding retries (put-text-property marker (+ marker region-length) 'media-state 'loading-failed) :loading-failed)))))) (defun mastodon-media--select-next-media-line (end-pos) "Find coordinates of the next media to load before END-POS. Returns the list of (`start' . `end', `media-symbol') points of that line and string found or nil no more media links were found." (let ((next-pos (point))) (while (and (setq next-pos (next-single-property-change next-pos 'media-state)) (or (not (eq 'needs-loading (get-text-property next-pos 'media-state))) (null (get-text-property next-pos 'media-url)) (null (get-text-property next-pos 'media-type)))) ;; do nothing - the loop will proceed ) (when (and next-pos (< next-pos end-pos)) (let ((media-type (get-text-property next-pos 'media-type))) (cond ((eq media-type 'avatar) ; avatars are one character (list next-pos (+ next-pos 1) 'avatar)) ((eq media-type 'media-link) ; media links are 5 characters: [img] (list next-pos (+ next-pos 5) 'media-link))))))) (defun mastodon-media--valid-link-p (link) "Check if LINK is valid. Checks to make sure the missing string has not been returned." (and link (> (length link) 8) (or (string= "http://" (substring link 0 7)) (string= "https://" (substring link 0 8))))) (defun mastodon-media--inline-images (search-start search-end) "Find all `Media_Links:' in the range from SEARCH-START to SEARCH-END. Replace them with the referenced image." (save-excursion (goto-char search-start) (let (line-details) (while (setq line-details (mastodon-media--select-next-media-line search-end)) (let* ((start (car line-details)) (end (cadr line-details)) (media-type (cadr (cdr line-details))) (type (get-text-property start 'mastodon-media-type)) (image-url (get-text-property start 'media-url))) (if (not (mastodon-media--valid-link-p image-url)) ;; mark it at least as not needing loading any more (put-text-property start end 'media-state 'invalid-url) ;; proceed to load this image asynchronously (put-text-property start end 'media-state 'loading) (mastodon-media--load-image-from-url image-url media-type start (- end start)) (when (or (equal type "gifv") (equal type "video")) (mastodon-media--moving-image-overlay start end)))))))) ;; (defvar-local mastodon-media--overlays nil ;; "Holds a list of overlays in the buffer.") (defun mastodon-media--moving-image-overlay (start end) "Add play symbol overlay to moving image media items." (let ((ov (make-overlay start end))) (overlay-put ov 'after-string (propertize "" 'help-echo "Video" 'face '((:height 3.5 :inherit 'font-lock-comment-face)))))) ;; (cl-pushnew ov mastodon-media--overlays))) (defun mastodon-media--get-avatar-rendering (avatar-url) "Return the string to be written that renders the avatar at AVATAR-URL." ;; We use just an empty space as the textual representation. ;; This is what a user will see on a non-graphical display ;; where not showing an avatar at all is preferable. (let ((image-options (when (or (image-type-available-p 'imagemagick) (image-transforms-p)) ; inbuilt scaling in 27.1 `(:height ,mastodon-media--avatar-height)))) (concat (propertize " " 'media-url avatar-url 'media-state 'needs-loading 'media-type 'avatar 'display (apply #'create-image mastodon-media--generic-avatar-data (if (version< emacs-version "27.1") (when image-options 'imagemagick) nil) ; inbuilt scaling in 27.1 t image-options)) " "))) (defun mastodon-media--get-media-link-rendering (media-url &optional full-remote-url type caption) "Return the string to be written that renders the image at MEDIA-URL. FULL-REMOTE-URL is used for `shr-browse-image'. TYPE is the attachment's type field on the server. CAPTION is the image caption if provided." (let* ((help-echo-base "RET/i: load full image (prefix: copy URL), +/-: zoom,\ r: rotate, o: save preview") (help-echo (if caption (concat help-echo-base "\n\"" caption "\"") help-echo-base))) (concat (mastodon-tl--propertize-img-str-or-url "[img]" media-url full-remote-url type help-echo (create-image mastodon-media--generic-broken-image-data nil t)) " "))) (provide 'mastodon-media) ;;; mastodon-media.el ends here