Ticket #3433: 3433_replay_cache_v1.1.patch

source/ps/VisualReplay.cpp

@@ -62 +62 @@
 }
 
 /**
- * Load all replays found in the directory.
- *
- * Since files are spread across the harddisk,
- * loading hundreds of them can consume a lot of time.
+ * Load the replay cache and check if there are new/deleted ones
+ * If so, update their data.
  */
 JS::Value VisualReplay::GetReplays(ScriptInterface& scriptInterface)
 {
@@ -72 +70 @@
     TIMER(L"GetReplays");
     JSContext* cx = scriptInterface.GetContext();
     JSAutoRequest rq(cx);
+    
+    std::map<CStr, u32> fileList;
 
+    const OsPath cacheFileName = GetDirectoryName() / L"replayCache.json";
+    JS::RootedObject cachedReplaysObject(cx);
+
+    bool cacheFound = FileExists(cacheFileName);
+    if (cacheFound)
+    {
+        // Open cache file
+        std::istream* cacheStream = new std::ifstream(cacheFileName.string8().c_str());
+
+        // Read file into chacheStr
+        CStr cacheStr((std::istreambuf_iterator<char>(*cacheStream)), std::istreambuf_iterator<char>());
+
+        // Create empty JS object and parse the context of the cache into it
+        JS::RootedValue cachedReplays(cx);
+        scriptInterface.Eval("({})", &cachedReplays);
+        scriptInterface.ParseJSON(cacheStr, &cachedReplays);
+        SAFE_DELETE(cacheStream);
+
+        JS::RootedObject temp(cx, &cachedReplays.toObject());
+        cachedReplaysObject = temp;
+
+        // Create list of files included in the cache
+        u32 cacheLength = 0;
+        JS_GetArrayLength(cx, cachedReplaysObject, &cacheLength);
+        for (u32 a = 0; a < cacheLength ; a++)
+        {
+            JS::RootedValue replay(cx);
+            JS_GetElement(cx, cachedReplaysObject, a, &replay);
+
+            JS::RootedObject replayObject(cx, &replay.toObject());
+            JS::RootedValue file(cx);
+            JS_GetProperty(cx, replayObject, "directory", &file);
+
+            CStr fileName;
+            scriptInterface.FromJSVal(cx, file, fileName);
+            fileList.emplace(fileName, a);
+        }
+    }
+
+    JS::RootedObject replays(cx, JS_NewArrayObject(cx, 0));
+    bool newReplays = false;
+    DirectoryNames directories;
     u32 i = 0;
-    DirectoryNames directories;
-    JS::RootedObject replays(cx, JS_NewArrayObject(cx, 0));
-
     if (GetDirectoryEntries(GetDirectoryName(), NULL, &directories) == INFO::OK)
+    {
         for (OsPath& directory : directories)
         {
             if (SDL_QuitRequested())
                 return JSVAL_NULL;
 
-            JS::RootedValue replayData(cx, LoadReplayData(scriptInterface, directory));
-            if (!replayData.isNull())
-                JS_SetElement(cx, replays, i++, replayData);
+            std::map<CStr, u32>::iterator it = fileList.find(directory.string8());
+            
+            // directory is not element of fileList
+            if (it == fileList.end())
+            {
+                JS::RootedValue replayData(cx, LoadReplayData(scriptInterface, directory));
+                if (!replayData.isNull())
+                {
+                    JS_SetElement(cx, replays, i++, replayData);
+                    newReplays = true;
+                }
+            }
+            else
+                fileList.erase(it);
         }
+
+        // No replay was changed, so just return the cache
+        if (!newReplays && fileList.empty())
+            return JS::ObjectValue(*cachedReplaysObject);
+        // Cache found, so copy the replays from the cache that are not deleted
+        else if (cacheFound)
+        {
+            std::vector<u32> deleteIndices;
+            for (auto const file : fileList)
+                deleteIndices.push_back(file.second);
+
+            u32 cacheLength = 0;
+            JS_GetArrayLength(cx, cachedReplaysObject, &cacheLength);
+
+            for (u32 a = 0; a < cacheLength; ++a)
+                // a not in deleteIndices, so copy it into replays
+                if (std::find(deleteIndices.begin(), deleteIndices.end(), a) == deleteIndices.end())
+                {
+                    JS::RootedValue replay(cx);
+                    JS_GetElement(cx, cachedReplaysObject, a, &replay);
+                    JS_SetElement(cx, replays, i++, replay);
+                }
+        }
+
+        JS::RootedValue replaysRooted(cx, JS::ObjectValue(*replays));
+        std::ofstream stream(cacheFileName.string8().c_str(), std::ofstream::out | std::ofstream::trunc);
+        stream << scriptInterface.StringifyJSON(&replaysRooted);
+        stream.close();
+    }
+
     return JS::ObjectValue(*replays);
 }