modules/page-modes/reddit.js

   1 /**
   2  * (C) Copyright 2008 Martin Dybdal
   3  * (C) Copyright 2009-2010 John Foerch
   4  *
   5  * Use, modification, and distribution are subject to the terms specified in the
   6  * COPYING file.
   7 **/
   8
   9 in_module(null);
  10
  11 require("content-buffer.js");
  12
  13 define_variable("reddit_end_behavior", "stop",
  14     "Controls the behavior of the commands reddit-next-link and "+
  15     "reddit-prev-link when at the last or first link, respectively. "+
  16     "Given as a string, the supported values are 'stop', 'wrap', "+
  17     "and 'page'.  'stop' means to not move the highlight in any "+
  18     "way.  'wrap' means to wrap around to the first (or last) "+
  19     "link.  'page' means to navigate the buffer to the next (or "+
  20     "previous) page on reddit.");
  21
  22 register_user_stylesheet(
  23     "data:text/css," +
  24         escape (
  25             "@-moz-document url-prefix(http://www.reddit.com/) {" +
  26                 ".last-clicked {" +
  27                 " background-color: #bfb !important;" +
  28                 " border: 0px !important;"+
  29                 "}}"));
  30
  31
  32 /* Scroll, if necessary, to make the given element visible */
  33 function reddit_scroll_into_view (window, element) {
  34     var rect = element.getBoundingClientRect();
  35     if (rect.top < 0 || rect.bottom > window.innerHeight)
  36         element.scrollIntoView();
  37 }
  38
  39
  40 /* Move select the next link down from the currently highlighted one.
  41  * When the end of the page is reached, the behavior is controlled by
  42  * the variable reddit_end_behavior.
  43  */
  44 function reddit_next (I) {
  45     var doc = I.buffer.document;
  46     // the behavior of this command depends on whether we have downloaded
  47     // enough of the page to include all of the article links.
  48     var complete = doc.getElementsByClassName('footer').length > 0;
  49     var links = doc.getElementsByClassName('link');
  50     var first = null;
  51     var current = null;
  52     var next = null;
  53     for (var i = 0, llen = links.length; i < llen; i++) {
  54         if (links[i].style.display == 'none')
  55             continue;
  56         if (! first)
  57             first = links[i];
  58         if (current) {
  59             next = links[i];
  60             break;
  61         }
  62         if (links[i].className.indexOf("last-clicked") >= 0)
  63             current = links[i];
  64     }
  65     // The following situations are null-ops:
  66     //  1) there are no links on the page.
  67     //  2) page is incomplete and the current link is the last link.
  68     if (!first || (current && !next && !complete))
  69         return;
  70     if (! next) {
  71         if (current) {
  72             if (reddit_end_behavior == 'stop')
  73                 return;
  74             if (reddit_end_behavior == 'wrap')
  75                 next = first;
  76             if (reddit_end_behavior == 'page') {
  77                 let (xpr = doc.evaluate(
  78                     '//p[@class="nextprev"]/a[text()="next"]', doc, null,
  79                     Ci.nsIDOMXPathResult.ORDERED_NODE_ITERATOR_TYPE, null))
  80                 {
  81                     let nextpage;
  82                     if (xpr && (nextpage = xpr.iterateNext())) {
  83                         dom_remove_class(current, "last-clicked");
  84                         browser_object_follow(I.buffer, FOLLOW_DEFAULT, nextpage);
  85                         return;
  86                     }
  87                 }
  88             }
  89         } else {
  90             // Page may or may not be complete.  If the page is not
  91             // complete, it is safe to assume that there is no current
  92             // link because a current link can only persist on a
  93             // cached page, which would load instantaneously, not
  94             // giving the user the opportunity to run this command.
  95             //
  96             next = first;
  97         }
  98     }
  99     // ordinaries (highlight new, maybe dehighlight old)
 100     if (current)
 101         dom_remove_class(current, "last-clicked");
 102     dom_add_class(next, "last-clicked");
 103     let (anchor = doc.evaluate(
 104         '//*[contains(@class,"last-clicked")]//a[contains(@class,"title")]',
 105         next, null, Ci.nsIDOMXPathResult.FIRST_ORDERED_NODE_TYPE, null))
 106     {
 107         browser_set_element_focus(I.buffer, anchor.singleNodeValue);
 108     }
 109     reddit_scroll_into_view(I.buffer.focused_frame, next);
 110 }
 111 interactive("reddit-next-link",
 112             "Move the 'cursor' to the next reddit entry.",
 113             reddit_next);
 114
 115
 116 /* Select the link before the currently highlighted one.  When the
 117  * beginning of the page is reached, behavior is controlled by the
 118  * variable reddit_end_behavior.
 119  */
 120 function reddit_prev (I) {
 121     var doc = I.buffer.document;
 122     // the behavior of this command depends on whether we have downloaded
 123     // enough of the page to include all of the article links.
 124     var complete = doc.getElementsByClassName('footer').length > 0;
 125     var links = doc.getElementsByClassName('link');
 126     var llen = links.length;
 127     var first = null;
 128     var prev = null;
 129     var current = null;
 130     for (var i = 0; i < llen; i++) {
 131         if (links[i].style.display == 'none')
 132             continue;
 133         if (! first)
 134             first = links[i];
 135         if (links[i].className.indexOf("last-clicked") >= 0) {
 136             current = links[i];
 137             break;
 138         }
 139         prev = links[i];
 140     }
 141     if (! first || // no links were found at all.
 142         (!current && !complete)) // don't know where current is.
 143         return;
 144     if (! prev) {
 145         // the first visible link is the `current' link.
 146         // dispatch on reddit_end_behavior.
 147         if (reddit_end_behavior == 'stop')
 148             return;
 149         else if (reddit_end_behavior == 'wrap') {
 150             // need to get last link on page.
 151             if (complete) {
 152                 for (var i = 0; i < llen; i++) {
 153                     if (links[i].style.display == 'none')
 154                         continue;
 155                     prev = links[i];
 156                 }
 157             }
 158         } else if (reddit_end_behavior == 'page') {
 159             let (xpr = doc.evaluate(
 160                 '//p[@class="nextprev"]/a[text()="prev"]', doc, null,
 161                 Ci.nsIDOMXPathResult.ORDERED_NODE_ITERATOR_TYPE, null))
 162             {
 163                 let prevpage;
 164                 if (xpr && (prevpage = xpr.iterateNext())) {
 165                     dom_remove_class(current, "last-clicked");
 166                     browser_object_follow(I.buffer, FOLLOW_DEFAULT, prevpage);
 167                     return;
 168                 }
 169             }
 170         }
 171     }
 172     // ordinaries (highlight new, maybe dehighlight old)
 173     if (current)
 174         dom_remove_class(current, "last-clicked");
 175     dom_add_class(prev, "last-clicked");
 176     let (anchor = doc.evaluate(
 177         '//*[contains(@class,"last-clicked")]//a[contains(@class,"title")]',
 178         prev, null, Ci.nsIDOMXPathResult.FIRST_ORDERED_NODE_TYPE, null))
 179     {
 180         browser_set_element_focus(I.buffer, anchor.singleNodeValue);
 181     }
 182     reddit_scroll_into_view(I.buffer.focused_frame, prev);
 183 }
 184 interactive("reddit-prev-link",
 185             "Move the 'cursor' to the previous reddit entry.",
 186             reddit_prev);
 187
 188
 189 function reddit_open_comments (I, target) {
 190     var xpr = I.buffer.document.evaluate(
 191         '//*[contains(@class,"last-clicked")]/descendant::a[@class="comments"]',
 192         I.buffer.document, null,
 193         Ci.nsIDOMXPathResult.ORDERED_NODE_ITERATOR_TYPE, null);
 194     let link;
 195     if (xpr && (link = xpr.iterateNext()))
 196         browser_object_follow(I.buffer, target || FOLLOW_DEFAULT, link);
 197 }
 198 function reddit_open_comments_new_buffer (I) {
 199     reddit_open_comments(I, OPEN_NEW_BUFFER);
 200 }
 201 function reddit_open_comments_new_window (I) {
 202     reddit_open_comments(I, OPEN_NEW_WINDOW);
 203 }
 204 interactive("reddit-open-comments",
 205             "Open the comments-page associated with the currently selected link.",
 206             alternates(reddit_open_comments,
 207                        reddit_open_comments_new_buffer,
 208                        reddit_open_comments_new_window));
 209
 210
 211 function reddit_vote_up (I) {
 212     // get the current article and send a click to its vote-up button.
 213     var xpr = I.buffer.document.evaluate(
 214         '//*[contains(@class,"last-clicked")]/div[contains(@class,"midcol")]/div[contains(@class,"up")]',
 215         I.buffer.document, null,
 216         Ci.nsIDOMXPathResult.ORDERED_NODE_ITERATOR_TYPE, null);
 217     let link;
 218     if (xpr && (link = xpr.iterateNext()))
 219         browser_object_follow(I.buffer, FOLLOW_DEFAULT, link);
 220 }
 221 interactive("reddit-vote-up",
 222             "Vote the currently selected link up.",
 223             reddit_vote_up);
 224
 225
 226 function reddit_vote_down (I) {
 227     // get the current article and send a click to its vote-down button.
 228     var xpr = I.buffer.document.evaluate(
 229         '//*[contains(@class,"last-clicked")]/div[contains(@class,"midcol")]/div[contains(@class,"down")]',
 230         I.buffer.document, null,
 231         Ci.nsIDOMXPathResult.ORDERED_NODE_ITERATOR_TYPE, null);
 232     let link;
 233     if (xpr && (link = xpr.iterateNext()))
 234         browser_object_follow(I.buffer, FOLLOW_DEFAULT, link);
 235 }
 236 interactive("reddit-vote-down",
 237             "Vote the currently selected link down.",
 238             reddit_vote_down);
 239
 240
 241 define_browser_object_class("reddit-current", null,
 242     function (I, prompt) {
 243         var xpr = I.buffer.document.evaluate(
 244             '//*[contains(@class,"last-clicked")]/*[contains(@class,"entry")]/p[@class="title"]/a',
 245             I.buffer.document, null,
 246             Ci.nsIDOMXPathResult.ORDERED_NODE_ITERATOR_TYPE, null);
 247         yield co_return(xpr.iterateNext());
 248     });
 249
 250
 251 define_keymap("reddit_keymap", $display_name = "reddit");
 252 define_key(reddit_keymap, "j", "reddit-next-link");
 253 define_key(reddit_keymap, "k", "reddit-prev-link");
 254 define_key(reddit_keymap, ",", "reddit-vote-up");
 255 define_key(reddit_keymap, ".", "reddit-vote-down");
 256 define_key(reddit_keymap, "h", "reddit-open-comments");
 257
 258
 259 var reddit_modality = {
 260     normal: reddit_keymap
 261 };
 262
 263
 264 define_page_mode("reddit-mode",
 265     build_url_regex($domain = /([a-zA-Z0-9\-]*\.)*reddit/),
 266     function enable (buffer) {
 267         let (cmds = ["follow-current",
 268                      "follow-current-new-buffer",
 269                      "follow-current-new-buffer-background",
 270                      "follow-current-new-window",
 271                      "copy"]) {
 272             for each (var c in cmds) {
 273                 buffer.default_browser_object_classes[c] =
 274                     browser_object_reddit_current;
 275             }
 276         }
 277         buffer.content_modalities.push(reddit_modality);
 278     },
 279     function disable (buffer) {
 280         var i = buffer.content_modalities.indexOf(reddit_modality);
 281         if (i > -1)
 282             buffer.content_modalities.splice(i, 1);
 283     },
 284     $display_name = "reddit",
 285     $doc = "reddit page-mode: keyboard navigation for reddit.");
 286
 287 page_mode_activate(reddit_mode);
 288
 289 provide("reddit");