modules/follow-relationship.js

   1 /**
   2  * (C) Copyright 2007-2008 Jeremy Maitin-Shepard
   3  *
   4  * Portions of this file were derived from Vimperator,
   5  * (C) Copyright 2007 Doug Kearns
   6  * (C) Copyright 2007-2008 Martin Stubenschrott.
   7  *
   8  * Use, modification, and distribution are subject to the terms specified in the
   9  * COPYING file.
  10 **/
  11
  12 require("element.js");
  13
  14 const RELATIONSHIP_NEXT = 0;
  15 const RELATIONSHIP_PREVIOUS = 1;
  16
  17 var browser_relationship_rel_name = ["next", "previous"];
  18 var browser_relationship_rel_regexp = ["next", "prev|previous"];
  19 var browser_relationship_rev_regexp = ["prev|previous", "next"];
  20
  21 define_variable("browser_relationship_patterns", {},
  22     "Patterns used by `follow-next' and `follow-previous'. "+
  23     "User value may be overridden for specific websites by "+
  24     "page-modes.");
  25
  26 browser_relationship_patterns[RELATIONSHIP_NEXT] =
  27     [/^next$/i,
  28      new RegExp("^>$","i"),
  29      new RegExp("^(>>|»)$","i"),
  30      new RegExp("^(>|»)","i"),
  31      new RegExp("(>|»)$","i"),
  32      new RegExp("\\bnext","i")
  33     ];
  34
  35 browser_relationship_patterns[RELATIONSHIP_PREVIOUS] =
  36     [/^(prev|previous)$/i,
  37      new RegExp("^<$","i"),
  38      new RegExp("^(<<|«)$","i"),
  39      new RegExp("^(<|«)","i"),
  40      new RegExp("(<|«)$","i"),
  41      new RegExp("\\bprev|previous\\b","i")
  42     ];
  43
  44 function document_get_element_by_relationship(buffer, doc, relationship) {
  45     var patterns = buffer.get('browser_relationship_patterns')[relationship];
  46     var rel_name = new RegExp(browser_relationship_rel_regexp[relationship], "i");
  47     var rev_name = new RegExp(browser_relationship_rev_regexp[relationship], "i");
  48
  49     var elems = doc.getElementsByTagName("link");
  50     // links have higher priority than normal <a> hrefs
  51     for (var i = 0; i < elems.length; i++)
  52     {
  53         if (rel_name.test(elems[i].rel) || rev_name.test(elems[i].rev))
  54             return elems[i];
  55     }
  56
  57     // no links? ok, look for hrefs
  58     elems = doc.getElementsByTagName("a");
  59     for (var i = 0; i < elems.length; i++)
  60     {
  61         if (rel_name.test(elems[i].rel) || rev_name.test(elems[i].rev))
  62             return elems[i];
  63     }
  64
  65     for (var j = 0; j < patterns.length; ++j)
  66     {
  67         var pattern = patterns[j];
  68         for (var i = 0; i < elems.length; i++) // Loop through list of A elements again
  69         {
  70             if (pattern.test(elems[i].textContent))
  71                 return elems[i];
  72
  73             // images with alt text being href
  74             var children = elems[i].childNodes;
  75             for (var k = 0; k < children.length; k++)
  76             {
  77                 if (pattern.test(children[k].alt))
  78                     return elems[i];
  79             }
  80         }
  81     }
  82     return null;
  83 }
  84
  85 function browser_follow_relationship(buffer, relationship, target) {
  86     check_buffer(buffer, content_buffer);
  87     for (let frame in frame_iterator(buffer.top_frame, buffer.focused_frame)) {
  88         let elem = document_get_element_by_relationship(
  89             buffer, frame.document, relationship);
  90         if (elem) {
  91             browser_element_follow(buffer, target, elem);
  92             return;
  93         }
  94     }
  95     throw interactive_error("No \"" + browser_relationship_rel_name[relationship]
  96                             + "\" link found");
  97 }
  98
  99 default_browse_targets["follow-relationship"] = "follow";
 100
 101 interactive("follow-next", null, function (I) {
 102     browser_follow_relationship(I.buffer, RELATIONSHIP_NEXT, I.browse_target("follow-relationship"))
 103 });
 104
 105 interactive("follow-previous", null, function (I) {
 106     browser_follow_relationship(I.buffer, RELATIONSHIP_PREVIOUS, I.browse_target("follow-relationship"))
 107 });