Adding ABP core modules to ABP/Opera

lib/matcher.js

+/*
+ * This Source Code is subject to the terms of the Mozilla Public License
+ * version 2.0 (the "License"). You can obtain a copy of the License at
+ * http://mozilla.org/MPL/2.0/.
+ */
+
+//
+// This mimicks the API of the Matcher module in ABP/Firefox but users Opera's
+// URLFilter API.
+//
+
+(function()
+{
+  var WhitelistFilter = null;
+  var RegExpFilter = null;
+  var resourceTypes = [
+      "DOCUMENT", "FONT", "IMAGE", "MEDIA", "OBJECT", "OBJECT_SUBREQUEST",
+      "OTHER", "SCRIPT", "STYLESHEET", "SUBDOCUMENT", "XMLHTTPREQUEST"
+  ];
+
+  require.scopes.matcher =
+  {
+    defaultMatcher:
+    {
+      _rules: {},
+
+      /**
+       * Converts rule text from Adblock Plus format (implicit * at beginning
+       * and end of the rule unless there is an anchor) to Opera format (* has
+       * to be specified explicitly).
+       */
+      _getRuleText: function(/**Filter*/ filter) /**String*/
+      {
+        var text = filter.regexpSource;
+
+        // |foo => foo
+        // foo => *foo
+        // *foo and ||foo stay unchanged
+        if (text.substr(0, 2) != "||")
+        {
+          var start = text.substr(0, 1);
+          if (start == "|")
+            text = text.slice(1);
+          else if (start != "*")
+            text = "*" + text;
+        }
+
+        // foo| => foo
+        // foo => foo*
+        // foo* stays unchanged
+        var end = text.substr(-1);
+        if (end == "|")
+          text = text.slice(0, -1);
+        else if (end != "*")
+          text = text + "*";
+
+        return text;
+      },
+
+      /**
+       * Converts type options of a filter into a bit mask as expected by Opera.
+       */
+      _getRuleTypes: function(/**Filter*/ filter) /**Integer*/
+      {
+        var types = 0;
+        var urlfilter = opera.extension.urlfilter;
+        for (var i = 0; i < resourceTypes.length; i++)
+        {
+          var type = resourceTypes[i];
+          if (filter.contentType & RegExpFilter.typeMap[type])
+            types |= urlfilter["RESOURCE_" + type];
+        }
+        return types;
+      },
+
+      /**
+       * Converts domain options of a filter into includeDomains/excludeDomains
+       * options as expected by Opera. The options object has to be passed in,
+       * properties will be added to it if necessary.
+       */
+      _getRuleDomains: function(/**Filter*/ filter, /**Object*/ options)
+      {
+        if (filter.domainSource)
+        {
+          var domains = filter.domainSource.split(filter.domainSeparator);
+          for (var i = 0; i < domains.length; i++)
+          {
+            var domain = domains[i];
+            if (domain == "")
+              continue;
+
+            var type = "includeDomains";
+            if (domain[0] == "~")
+            {
+              type = "excludeDomains";
+              domain = domain.substr(1);
+            }
+            if (!(type in options))
+              options[type] = [];
+            options[type].push(domain);
+          }
+        }
+      },
+
+      /**
+       * Converts third-party filter option to the format expected by Opera.
+       * The options object has to be passed in, a property will be added to it
+       * if necessary.
+       */
+      _getRuleThirdParty: function(/**Filter*/ filter, /**Object*/ options)
+      {
+        if (filter.thirdParty !== null)
+          options.thirdParty = filter.thirdParty;
+      },
+
+      /**
+       * Converts an Adblock Plus filter to a rule that can be processed by
+       * Opera. The following options will be set:
+       *
+       *  type: urlfilter to be used, either "allow" or "block"
+       *  text: rule text
+       *  options: rule options
+       */
+      _generateRule: function(/**Filter*/ filter) /**Object*/
+      {
+        if (!WhitelistFilter)
+        {
+          WhitelistFilter = require("filterClasses").WhitelistFilter;
+          RegExpFilter = require("filterClasses").RegExpFilter;
+        }
+
+        var rule = {
+          type: filter instanceof WhitelistFilter ? "allow" : "block",
+          text: this._getRuleText(filter),
+          options: {
+            resources: this._getRuleTypes(filter)
+          }
+        };
+        this._getRuleDomains(filter, rule.options);
+        this._getRuleThirdParty(filter, rule.options);
+        return rule;
+      },
+
+      add: function(filter)
+      {
+        if (filter.text in this._rules)
+          return;
+
+        var rule = this._generateRule(filter);
+        opera.extension.urlfilter[rule.type].add(rule.text, rule.options);
+        this._rules[filter.text] = rule;
+      },
+
+      remove: function(filter)
+      {
+        if (!(filter.text in this._rules))
+          return;
+
+        var rule = this._rules[filter.text];
+        opera.extension.urlfilter[rule.type].remove(rule.text);
+        delete this._rules[filter.text];
+      },
+
+      clear: function()
+      {
+        for (var text in this._rules)
+        {
+          var rule = this._rules[text];
+          opera.extension.urlfilter[rule.type].remove(rule.text);
+        }
+        this._rules = {};
+      }
+    }
+  };
+})();