Refactor|FS: Continued refactoring remote file repository classes

The different types of repositories form a class hierarchy, and
the application (DoomsdayApp) can register its own repository type(s).
libcore just provides access to the serverside files.

doomsday/apps/client/src/network/packagedownloader.cpp

@@ -240,15 +240,15 @@ void PackageDownloader::mountFileRepository(shell::ServerInfo const &info)
     // The remote repository feature was added in 2.1. Trying to send a RemoteFeed
     // request to an older server would just result in us getting immediately
     // disconnected.
+
     if (info.version() > Version(2, 1, 0, 2484))
     {
-        d->fileRepository = info.address().asText();
+        d->fileRepository = "doomsday:" + info.address().asText();
         d->isCancelled = false;
         FS::get().makeFolderWithFeed
                 (PATH_REMOTE_SERVER,
-                 RemoteFeedRelay::get().addRepository(RemoteFeedRelay::Server,
-                                                      d->fileRepository,
-                                                      PATH_SERVER_REPOSITORY_ROOT),
+                 filesys::RemoteFeedRelay::get().addRepository(d->fileRepository,
+                                                               PATH_SERVER_REPOSITORY_ROOT),
                  Folder::PopulateAsyncFullTree);
     }
 }
@@ -261,7 +261,7 @@ void PackageDownloader::unmountFileRepository()
     {
         trash(remoteFiles);
     }
-    RemoteFeedRelay::get().removeRepository(d->fileRepository);
+    filesys::RemoteFeedRelay::get().removeRepository(d->fileRepository);
     d->fileRepository.clear();
     d->isCancelled = false;
 }

doomsday/apps/libdoomsday/include/doomsday/filesys/idgameslink.h

@@ -27,6 +27,8 @@ class IdgamesLink : public de::filesys::WebHostedLink
     IdgamesLink(de::String const &address);
 
     void parseRepositoryIndex(QByteArray data) override;
+
+    static de::filesys::Link *construct(de::String const &address);
 };
 
 #endif // LIBDOOMSDAY_FILESYS_IDGAMESLINK_H

doomsday/apps/libdoomsday/src/doomsdayapp.cpp

@@ -28,6 +28,7 @@
 #include "doomsday/filesys/datafile.h"
 #include "doomsday/filesys/datafolder.h"
 #include "doomsday/filesys/virtualmappings.h"
+#include "doomsday/filesys/idgameslink.h"
 #include "doomsday/busymode.h"
 #include "doomsday/world/world.h"
 #include "doomsday/world/entitydef.h"
@@ -151,6 +152,9 @@ DENG2_PIMPL(DoomsdayApp)
             }
         });
         configSaveTimer.start();
+
+        // File system extensions.
+        filesys::RemoteFeedRelay::get().defineLink(IdgamesLink::construct);
     }
 
     ~Impl()
@@ -389,8 +393,7 @@ DENG2_PIMPL(DoomsdayApp)
     void initRemoteRepositories()
     {
         FS::get().makeFolderWithFeed("/remote/idgames",
-                RemoteFeedRelay::get().addRepository(RemoteFeedRelay::IdgamesFileTree,
-                                                     "http://www.gamers.org/pub/idgames/"),
+                filesys::RemoteFeedRelay::get().addRepository("http://www.gamers.org/pub/idgames/"),
                 Folder::PopulateAsyncFullTree);
     }
 

doomsday/apps/libdoomsday/src/filesys/idgameslink.cpp

@@ -108,5 +108,15 @@ void IdgamesLink::parseRepositoryIndex(QByteArray data)
             handleError("Failed to parse directory listing: " + errorMessage);
             wasDisconnected();
         }
-    });
+});
+}
+
+filesys::Link *IdgamesLink::construct(String const &address)
+{
+    if ((address.startsWith("http:") || address.startsWith("https:")) &&
+        !address.contains("dengine.net"))
+    {
+        return new IdgamesLink(address);
+    }
+    return nullptr;
 }

doomsday/sdk/libcore/include/de/core/app.h

@@ -48,11 +48,11 @@ class Module;
 class Path;
 class NativePath;
 class PackageLoader;
-class RemoteFeedRelay;
 class ScriptSystem;
 class System;
 class UnixInfo;
 
+namespace filesys { class RemoteFeedRelay; }
 namespace game { class Game; }
 
 /**
@@ -296,7 +296,7 @@ class DENG2_PUBLIC App : DENG2_OBSERVES(Clock, TimeChange)
     /**
      * Returns the remote feed relay that manages connections to remote file repositories.
      */
-    static RemoteFeedRelay &remoteFeedRelay();
+    static filesys::RemoteFeedRelay &remoteFeedRelay();
 
     /**
      * Returns the application's package loader.

doomsday/sdk/libcore/include/de/filesys/Query

@@ -0,0 +1,2 @@
+#include "remote/query.h"
+

doomsday/sdk/libcore/include/de/filesys/remote/link.h

@@ -21,8 +21,8 @@
 
 #include "../../DictionaryValue"
 #include "../../IdentifiedPacket"
-#include "../../RemoteFeedRelay"
 #include "../../String"
+#include "../Query"
 
 namespace de {
 
@@ -31,49 +31,31 @@ class AsyncScope;
 namespace filesys {
 
 /**
- * Active connection to a remote repository. One link is shared by all
- * RemoteFeed instances accessing the same repository.
+ * Base class for an active connection to a remote repository. Specialized subclasses
+ * handle specific types of repositories. One link instance is shared by all RemoteFeed
+ * instances accessing the same repository.
+ *
+ * @ingroup fs
  */
 class DENG2_PUBLIC Link
 {
 public:
     enum State { Deinitialized, Initializing, Ready };
 
-    using QueryId = IdentifiedPacket::Id;
-
-    struct DENG2_PUBLIC Query
-    {
-        QueryId id;
-        String path;
-        RemoteFeedRelay::FileListRequest fileList;
-        RemoteFeedRelay::FileContentsRequest fileContents;
-        duint64 receivedBytes = 0;
-        duint64 fileSize = 0;
-
-        Query(RemoteFeedRelay::FileListRequest req, String path);
-        Query(RemoteFeedRelay::FileContentsRequest req, String path);
-        bool isValid() const;
-        void cancel();
-    };
+    typedef std::function<Link * (String const &address)> Constructor;
 
 public:
-    Link(String const &address);
-
     virtual ~Link();
 
     String address() const;
 
     State state() const;
 
-    virtual void wasConnected();
-
-    virtual void wasDisconnected();
-
-    virtual void handleError(QString errorMessage);
-
     void sendQuery(Query query);
 
 protected:
+    Link(String const &address);
+
     AsyncScope &scope();
 
     Query *findQuery(QueryId id);
@@ -86,6 +68,12 @@ class DENG2_PUBLIC Link
 
     void chunkReceived(QueryId id, duint64 startOffset, Block const &chunk, duint64 fileSize);
 
+    virtual void wasConnected();
+
+    virtual void wasDisconnected();
+
+    virtual void handleError(QString errorMessage);
+
     virtual void transmit(Query const &query) = 0;
 
 private:
@@ -95,4 +83,4 @@ class DENG2_PUBLIC Link
 } // namespace filesys
 } // namespace de
 
-#endif // DENG2_REMOTE_REPOSITORYLINK_H
+#endif // DENG2_FILESYS_LINK_H

doomsday/sdk/libcore/include/de/filesys/remote/nativelink.h

@@ -30,9 +30,11 @@ namespace filesys {
 class DENG2_PUBLIC NativeLink : public Link
 {
 public:
-    NativeLink(String const &address);
+    static Link *construct(String const &address);
 
 protected:
+    NativeLink(String const &address);
+
     void wasConnected() override;
     void transmit(Query const &query) override;
 

doomsday/sdk/libcore/include/de/filesys/remote/query.h

@@ -0,0 +1,66 @@
+/** @file remote/query.h
+ *
+ * @authors Copyright (c) 2017 Jaakko Keränen <jaakko.keranen@iki.fi>
+ *
+ * @par License
+ * LGPL: http://www.gnu.org/licenses/lgpl.html
+ *
+ * <small>This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or (at your
+ * option) any later version. This program is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
+ * General Public License for more details. You should have received a copy of
+ * the GNU Lesser General Public License along with this program; if not, see:
+ * http://www.gnu.org/licenses</small>
+ */
+
+#ifndef DENG2_FILESYS_QUERY_H
+#define DENG2_FILESYS_QUERY_H
+
+#include "../../AsyncCallback"
+#include "../../DictionaryValue"
+#include "../../IdentifiedPacket"
+
+namespace de {
+namespace filesys {
+
+typedef DictionaryValue FileList;
+
+typedef std::function<void (FileList const &)> FileListFunc;
+typedef std::function<void (duint64 startOffset, Block const &, duint64 remainingBytes)> DataReceivedFunc;
+
+typedef std::shared_ptr<AsyncCallback<FileListFunc>>     FileListRequest;
+typedef std::shared_ptr<AsyncCallback<DataReceivedFunc>> FileContentsRequest;
+
+using QueryId = IdentifiedPacket::Id;
+
+/**
+ * Query about information stored in the remote repository. The callbacks will
+ * be called when a reply is received.
+ */
+struct DENG2_PUBLIC Query
+{
+    // Query parameters:
+    QueryId id;
+    String path;
+
+    // Callbacks:
+    FileListRequest fileList;
+    FileContentsRequest fileContents;
+
+    // Internal status:
+    duint64 receivedBytes = 0;
+    duint64 fileSize = 0;
+
+    Query(FileListRequest req, String path);
+    Query(FileContentsRequest req, String path);
+    bool isValid() const;
+    void cancel();
+};
+
+} // namespace filesys
+} // namespace de
+
+#endif // DENG2_FILESYS_QUERY_H

doomsday/sdk/libcore/include/de/filesys/remote/remotefeedrelay.h

@@ -23,10 +23,13 @@
 #include "../../Record"
 #include "../../DictionaryValue"
 #include "../../AsyncCallback"
+#include "../Query"
+#include "../Link"
 
 #include <QNetworkAccessManager>
 
 namespace de {
+namespace filesys {
 
 /**
  * Connects to one or more remote file repositories and provides metadata and file
@@ -35,21 +38,13 @@ namespace de {
 class DENG2_PUBLIC RemoteFeedRelay
 {
 public:
-    typedef DictionaryValue FileList;
-
-    typedef std::function<void (FileList const &)> FileListFunc;
-    typedef std::function<void (duint64 startOffset, Block const &, duint64 remainingBytes)> DataReceivedFunc;
-
-    typedef std::shared_ptr<AsyncCallback<FileListFunc>>     FileListRequest;
-    typedef std::shared_ptr<AsyncCallback<DataReceivedFunc>> FileContentsRequest;
-
     static RemoteFeedRelay &get();
 
-    enum RepositoryType {
-        Server,
-        NativePackages,
-        IdgamesFileTree,
-    };
+//    enum RepositoryType {
+//        Server,
+//        NativePackages,
+//        IdgamesFileTree,
+//    };
 
     enum Status { Disconnected, Connected };
 
@@ -58,7 +53,16 @@ class DENG2_PUBLIC RemoteFeedRelay
 public:
     RemoteFeedRelay();
 
-    RemoteFeed *addRepository(RepositoryType type, String const &address, String const &remoteRoot = "/");
+    /**
+     * Defines a new type of remote repository link. The defined links are each
+     * offered a remote repository address, and the first one to create a Link instance
+     * based on the address will be used to communicate with the repository.
+     *
+     * @param linkConstructor  Constructor method.
+     */
+    void defineLink(Link::Constructor linkConstructor);
+
+    RemoteFeed *addRepository(String const &address, String const &remoteRoot = "/");
 
     void removeRepository(String const &address);
 
@@ -80,6 +84,7 @@ class DENG2_PUBLIC RemoteFeedRelay
     DENG2_PRIVATE(d)
 };
 
+} // namespace filesys
 } // namespace de
 
 #endif // LIBDENG2_REMOTEFEEDRELAY_H

doomsday/sdk/libcore/src/core/app.cpp

@@ -101,7 +101,7 @@ DENG2_PIMPL(App)
 
     std::unique_ptr<UnixInfo> unixInfo;
 
-    RemoteFeedRelay remoteFeedRelay;
+    filesys::RemoteFeedRelay remoteFeedRelay;
 
     /// The configuration.
     Path configPath;
@@ -892,7 +892,7 @@ Folder &App::homeFolder()
     return rootFolder().locate<Folder>("home");
 }
 
-RemoteFeedRelay &App::remoteFeedRelay()
+filesys::RemoteFeedRelay &App::remoteFeedRelay()
 {
     return DENG2_APP->d->remoteFeedRelay;
 }