/** * (c) 2010 StatusNet, Inc. */ (function() { /** * Quickie wrapper around ooembed JSON lookup */ var oEmbed = { api: 'http://oohembed.com/oohembed', width: 100, height: 75, cache: {}, callbacks: {}, /** * Do a cached oEmbed lookup for the given URL. * * @param {String} url * @param {function} callback */ lookup: function(url, callback) { if (typeof oEmbed.cache[url] == "object") { // We already have a successful lookup. callback(oEmbed.cache[url]); } else if (typeof oEmbed.callbacks[url] == "undefined") { // No lookup yet... Start it! oEmbed.callbacks[url] = [callback]; oEmbed.rawLookup(url, function(data) { oEmbed.cache[url] = data; var callbacks = oEmbed.callbacks[url]; oEmbed.callbacks[url] = undefined; for (var i = 0; i < callbacks.length; i++) { callbacks[i](data); } }); } else { // A lookup is in progress. oEmbed.callbacks[url].push(callback); } }, /** * Do an oEmbed lookup for the given URL. * * @fixme proxy through ourselves if possible? * @fixme use the global thumbnail size settings * * @param {String} url * @param {function} callback */ rawLookup: function(url, callback) { var params = { url: url, format: 'json', maxwidth: oEmbed.width, maxheight: oEmbed.height, token: $('#token').val() }; $.ajax({ url: oEmbed.api, data: params, dataType: 'json', success: function(data, xhr) { callback(data); }, error: function(xhr, textStatus, errorThrown) { callback(null); } }); } }; var LinkPreview = { links: [], state: [], refresh: [], /** * Find URL links from the source text that may be interesting. * * @param {String} text * @return {Array} list of URLs */ findLinks: function (text) { // @fixme match this to core code var re = /(?:^| )(https?:\/\/.+?\/.+?)(?= |$)/mg; var links = []; var matches; while ((matches = re.exec(text)) !== null) { links.push(matches[1]); } return links; }, /** * Start looking up info for a link preview... * May start async data loads. * * @param {number} col: column number to insert preview into */ prepLinkPreview: function(col) { var id = 'link-preview-' + col; var url = LinkPreview.links[col]; LinkPreview.refresh[col] = false; LinkPreview.markLoading(col); oEmbed.lookup(url, function(data) { var thumb = null; var width = 100; if (data && typeof data.thumbnail_url == "string") { thumb = data.thumbnail_url; if (typeof data.thumbnail_width !== "undefined") { if (data.thumbnail_width < width) { width = data.thumbnail_width; } } } else if (data && data.type == 'photo' && typeof data.url == "string") { thumb = data.url; if (typeof data.width !== "undefined") { if (data.width < width) { width = data.width; } } } if (thumb) { var link = $('<span class="inline-attachment"><a><img/></a></span>'); link.find('a') .attr('href', url) .attr('target', '_blank') .last() .find('img') .attr('src', thumb) .attr('width', width) .attr('title', data.title || data.url || url); $('#' + id).empty(); $('#' + id).append(link); } else { // No thumbnail available or error retriving it. LinkPreview.clearLink(col); } if (LinkPreview.refresh[col]) { // Darn user has typed more characters. // Go fetch another link! LinkPreview.prepLinkPreview(col); } else { LinkPreview.markDone(col); } }); }, /** * Update the live preview section with links found in the given text. * May start async data loads. * * @param {String} text: free-form input text */ previewLinks: function(text) { var i; var old = LinkPreview.links; var links = LinkPreview.findLinks(text); LinkPreview.links = links; // Check for existing common elements... for (i = 0; i < old.length && i < links.length; i++) { if (links[i] != old[i]) { if (LinkPreview.state[i] == "loading") { // Slate this column for a refresh when this one's done. LinkPreview.refresh[i] = true; } else { // Change an existing entry! LinkPreview.prepLinkPreview(i); } } } if (links.length > old.length) { // Adding new entries, whee! for (i = old.length; i < links.length; i++) { LinkPreview.addPreviewArea(i); LinkPreview.prepLinkPreview(i); } } else if (old.length > links.length) { // Remove preview entries for links that have been removed. for (i = links.length; i < old.length; i++) { LinkPreview.clearLink(i); } } }, addPreviewArea: function(col) { var id = 'link-preview-' + col; $('#link-preview').append('<span id="' + id + '"></span>'); }, clearLink: function(col) { var id = 'link-preview-' + col; $('#' + id).html(''); }, markLoading: function(col) { LinkPreview.state[col] = "loading"; var id = 'link-preview-' + col; $('#' + id).attr('style', 'opacity: 0.5'); }, markDone: function(col) { LinkPreview.state[col] = "done"; var id = 'link-preview-' + col; $('#' + id).removeAttr('style'); }, /** * Clear out any link preview data. */ clear: function() { LinkPreview.links = []; $('#link-preview').empty(); } }; SN.Init.LinkPreview = function(params) { if (params.api) oEmbed.api = params.api; if (params.width) oEmbed.width = params.width; if (params.height) oEmbed.height = params.height; $('#form_notice') .append('<div id="link-preview" class="thumbnails"></div>') .bind('reset', function() { LinkPreview.clear(); }); // Piggyback on the counter update... var origCounter = SN.U.Counter; SN.U.Counter = function(form) { LinkPreview.previewLinks($('#notice_data-text').val()); return origCounter(form); } } })();