Issue 5146 - Implement DownloadableSubscription parsing in C++

lib/synchronizer.js

Index: lib/synchronizer.js
===================================================================
--- a/lib/synchronizer.js
+++ b/lib/synchronizer.js
@@ -19,22 +19,20 @@
 
 /**
  * @fileOverview Manages synchronization of filter subscriptions.
  */
 
 const {Downloader, Downloadable,
        MILLIS_IN_SECOND, MILLIS_IN_MINUTE,
        MILLIS_IN_HOUR, MILLIS_IN_DAY} = require("downloader");
-const {Filter} = require("filterClasses");
 const {FilterStorage} = require("filterStorage");
 const {FilterNotifier} = require("filterNotifier");
 const {Prefs} = require("prefs");
 const {Subscription, DownloadableSubscription} = require("subscriptionClasses");
-const {Utils} = require("utils");
 
 const INITIAL_DELAY = 1 * MILLIS_IN_MINUTE;
 const CHECK_INTERVAL = 1 * MILLIS_IN_HOUR;
 const DEFAULT_EXPIRATION_INTERVAL = 5 * MILLIS_IN_DAY;
 
 /**
  * The object providing actual downloading functionality.
  * @type {Downloader}
@@ -148,148 +146,91 @@
                      redirectCallback)
   {
     let lines = responseText.split(/[\r\n]+/);
     let headerMatch = /\[Adblock(?:\s*Plus\s*([\d.]+)?)?\]/i.exec(lines[0]);
     if (!headerMatch)
       return errorCallback("synchronize_invalid_data");
     let minVersion = headerMatch[1];
 
-    // Don't remove parameter comments immediately but add them to a list first,
-    // they need to be considered in the checksum calculation.
-    let remove = [];
-    let params = {
-      redirect: null,
-      homepage: null,
-      title: null,
-      version: null,
-      expires: null
-    };
-    for (let i = 0; i < lines.length; i++)
+    let parser = DownloadableSubscription.parseDownload();
+
+    // Process filters
+    for (let line of lines)
+      parser.process(line);
+
+    if (parser.redirect)
     {
-      let match = /^\s*!\s*(\w+)\s*:\s*(.*)/.exec(lines[i]);
-      if (match)
-      {
-        let keyword = match[1].toLowerCase();
-        let value = match[2];
-        if (keyword in params)
-        {
-          params[keyword] = value;
-          remove.push(i);
-        }
-        else if (keyword == "checksum")
-        {
-          lines.splice(i--, 1);
-          let checksum = Utils.generateChecksum(lines);
-          if (checksum && checksum != value.replace(/=+$/, ""))
-            return errorCallback("synchronize_checksum_mismatch");
-        }
-      }
+      let {redirect} = parser;
+      parser.delete();
+      return redirectCallback(redirect);
     }
 
-    if (params.redirect)
-      return redirectCallback(params.redirect);
-
     // Handle redirects
     let subscription = Subscription.fromURL(downloadable.redirectURL ||
                                             downloadable.url);
     if (downloadable.redirectURL &&
         downloadable.redirectURL != downloadable.url)
     {
       let oldSubscription = Subscription.fromURL(downloadable.url);
       subscription.title = oldSubscription.title;
       subscription.disabled = oldSubscription.disabled;
       subscription.lastCheck = oldSubscription.lastCheck;
 
-      let listed = (oldSubscription.url in FilterStorage.knownSubscriptions);
+      let {listed} = oldSubscription;
       if (listed)
         FilterStorage.removeSubscription(oldSubscription);
 
-      delete Subscription.knownSubscriptions[oldSubscription.url];
-
       if (listed)
         FilterStorage.addSubscription(subscription);
     }
 
     // The download actually succeeded
     subscription.lastSuccess = subscription.lastDownload = Math.round(
       Date.now() / MILLIS_IN_SECOND
     );
     subscription.downloadStatus = "synchronize_ok";
     subscription.downloadCount = downloadable.downloadCount;
     subscription.errors = 0;
 
-    // Remove lines containing parameters
-    for (let i = remove.length - 1; i >= 0; i--)
-      lines.splice(remove[i], 1);
-
     // Process parameters
-    if (params.homepage)
+    if (parser.homepage)
     {
       let url;
       try
       {
-        url = new URL(params.homepage);
+        url = new URL(parser.homepage);
       }
       catch (e)
       {
         url = null;
       }
 
       if (url && (url.protocol == "http:" || url.protocol == "https:"))
         subscription.homepage = url.href;
     }
 
-    if (params.title)
-    {
-      subscription.title = params.title;
-      subscription.fixedTitle = true;
-    }
+    if (minVersion)
+      subscription.requiredVersion = minVersion;
     else
-      subscription.fixedTitle = false;
-
-    subscription.version = (params.version ? parseInt(params.version, 10) : 0);
+      delete subscription.requiredVersion;
 
     let expirationInterval = DEFAULT_EXPIRATION_INTERVAL;
-    if (params.expires)
-    {
-      let match = /^(\d+)\s*(h)?/.exec(params.expires);
-      if (match)
-      {
-        let interval = parseInt(match[1], 10);
-        if (match[2])
-          expirationInterval = interval * MILLIS_IN_HOUR;
-        else
-          expirationInterval = interval * MILLIS_IN_DAY;
-      }
-    }
+    let expiration = parser.finalize(subscription);
+    if (expiration != 0)
+      expirationInterval = expiration;
 
     let [
       softExpiration,
       hardExpiration
     ] = downloader.processExpirationInterval(expirationInterval);
     subscription.softExpiration = Math.round(softExpiration / MILLIS_IN_SECOND);
     subscription.expires = Math.round(hardExpiration / MILLIS_IN_SECOND);
 
-    if (minVersion)
-      subscription.requiredVersion = minVersion;
-    else
-      delete subscription.requiredVersion;
-
-    // Process filters
-    lines.shift();
-    let filters = [];
-    for (let line of lines)
-    {
-      line = Filter.normalize(line);
-      if (line)
-        filters.push(Filter.fromText(line));
-    }
-
-    FilterStorage.updateSubscriptionFilters(subscription, filters);
+    parser.delete();
 
     return undefined;
   },
 
   _onDownloadError(downloadable, downloadURL, error, channelStatus,
                    responseStatus, redirectCallback)
   {
     let subscription = Subscription.fromURL(downloadable.url);
@@ -329,29 +270,29 @@
         request.channel.loadFlags = request.channel.loadFlags |
                                     request.channel.INHIBIT_CACHING |
                                     request.channel.VALIDATE_ALWAYS;
         request.addEventListener("load", ev =>
         {
           if (onShutdown.done)
             return;
 
-          if (!(subscription.url in FilterStorage.knownSubscriptions))
+          if (!subscription.listed)
             return;
 
           let match = /^(\d+)(?:\s+(\S+))?$/.exec(request.responseText);
           if (match && match[1] == "301" &&    // Moved permanently
               match[2] && /^https?:\/\//i.test(match[2]))
           {
             redirectCallback(match[2]);
           }
           else if (match && match[1] == "410") // Gone
           {
             let data = "[Adblock]\n" +
-              subscription.filters.map(f => f.text).join("\n");
+              Array.from(subscription.filters, f => f.text).join("\n");
             redirectCallback("data:text/plain," + encodeURIComponent(data));
           }
         }, false);
         request.send(null);
       }
     }
   }
 };