Introduce a user scripts mechanism

Allowing programmatic injection of JavaScript to accomplish
all sorts of tasks on the render process side.
This API gives control over the point during the loading phase
at which the script is run, whether it is run on sub-frames or
not, as well as the JavaScript world it is run in (either the
page's main world, or an arbitrary isolated world).

This only has the Widgets API. The Quick API, tests and docs
are coming in separate patches

Change-Id: Ia1c79f68f8dfd4d964281d9723d09062ed7abe46
Reviewed-by: Andras Becsi <andras.becsi@theqtcompany.com>

3 files changed, 344 insertions, 0 deletions

diff --git a/src/core/renderer/content_renderer_client_qt.cpp b/src/core/renderer/content_renderer_client_qt.cpp
index bde8e8455..242c8ef6d 100644
--- a/src/core/renderer/content_renderer_client_qt.cpp
+++ b/src/core/renderer/content_renderer_client_qt.cpp
@@ -52,6 +52,7 @@
 
 #include "renderer/web_channel_ipc_transport.h"
 #include "renderer/qt_render_view_observer.h"
+#include "renderer/user_script_controller.h"
 
 #include "grit/renderer_resources.h"
 
@@ -71,6 +72,7 @@ void ContentRendererClientQt::RenderThreadStarted()
     renderThread->RegisterExtension(WebChannelIPCTransport::getV8Extension());
     m_visitedLinkSlave.reset(new visitedlink::VisitedLinkSlave);
     renderThread->AddObserver(m_visitedLinkSlave.data());
+    renderThread->AddObserver(UserScriptController::instance());
 }
 
 void ContentRendererClientQt::RenderViewCreated(content::RenderView* render_view)
@@ -78,6 +80,7 @@ void ContentRendererClientQt::RenderViewCreated(content::RenderView* render_view
     // RenderViewObservers destroy themselves with their RenderView.
     new QtRenderViewObserver(render_view);
     new WebChannelIPCTransport(render_view);
+    UserScriptController::instance()->renderViewCreated(render_view);
 }
 
 bool ContentRendererClientQt::HasErrorPage(int httpStatusCode, std::string *errorDomain)
diff --git a/src/core/renderer/user_script_controller.cpp b/src/core/renderer/user_script_controller.cpp
new file mode 100644
index 000000000..729500341
--- /dev/null
+++ b/src/core/renderer/user_script_controller.cpp
@@ -0,0 +1,259 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "user_script_controller.h"
+
+#include "content/public/renderer/render_view.h"
+#include "content/public/renderer/render_view_observer.h"
+#include "third_party/WebKit/public/web/WebLocalFrame.h"
+#include "third_party/WebKit/public/web/WebScriptSource.h"
+#include "third_party/WebKit/public/web/WebView.h"
+#include "v8/include/v8.h"
+
+#include "common/qt_messages.h"
+#include "common/user_script_data.h"
+
+Q_GLOBAL_STATIC(UserScriptController, qt_webengine_userScriptController)
+
+static content::RenderView * const globalScriptsIndex = 0;
+
+// Scripts meant to run after the load event will be run 500ms after DOMContentLoaded if the load event doesn't come within that delay.
+static const int afterLoadTimeout = 500;
+
+class UserScriptController::RenderViewObserverHelper : public content::RenderViewObserver
+{
+public:
+    RenderViewObserverHelper(content::RenderView *);
+private:
+    // RenderViewObserver implementation.
+    virtual void DidCreateDocumentElement(blink::WebLocalFrame* frame) Q_DECL_OVERRIDE;
+    virtual void DidFinishDocumentLoad(blink::WebLocalFrame* frame) Q_DECL_OVERRIDE;
+    virtual void DidFinishLoad(blink::WebLocalFrame* frame) Q_DECL_OVERRIDE;
+    virtual void DidStartProvisionalLoad(blink::WebLocalFrame* frame) Q_DECL_OVERRIDE;
+    virtual void FrameDetached(blink::WebFrame* frame) Q_DECL_OVERRIDE;
+    virtual void OnDestruct() Q_DECL_OVERRIDE;
+    virtual bool OnMessageReceived(const IPC::Message& message) Q_DECL_OVERRIDE;
+
+    void onUserScriptAdded(const UserScriptData &);
+    void onUserScriptRemoved(const UserScriptData &);
+    void onScriptsCleared();
+
+    void runScripts(UserScriptData::InjectionPoint, blink::WebLocalFrame *);
+    QSet<blink::WebLocalFrame *> m_pendingFrames;
+};
+
+void UserScriptController::RenderViewObserverHelper::runScripts(UserScriptData::InjectionPoint p, blink::WebLocalFrame *frame)
+{
+    if (p == UserScriptData::AfterLoad && !m_pendingFrames.remove(frame))
+        return;
+    content::RenderView *renderView = content::RenderView::FromWebView(frame->view());
+    const bool isMainFrame = (frame == renderView->GetWebView()->mainFrame());
+
+    QList<uint64> scriptsToRun = UserScriptController::instance()->m_viewUserScriptMap.value(globalScriptsIndex).toList();
+    scriptsToRun.append(UserScriptController::instance()->m_viewUserScriptMap.value(renderView).toList());
+
+    Q_FOREACH (uint64 id, scriptsToRun) {
+        const UserScriptData &script = UserScriptController::instance()->m_scripts.value(id);
+        if (script.injectionPoint != p
+                || (!script.injectForSubframes && !isMainFrame))
+            continue;
+        blink::WebScriptSource source(blink::WebString::fromUTF8(script.source), script.url);
+        if (script.worldId)
+            frame->executeScriptInIsolatedWorld(script.worldId, &source, /*numSources = */1, /*contentScriptExtentsionGroup = */ 1);
+        else
+            frame->executeScript(source);
+    }
+}
+
+
+UserScriptController::RenderViewObserverHelper::RenderViewObserverHelper(content::RenderView *renderView)
+    : content::RenderViewObserver(renderView)
+{
+}
+
+void UserScriptController::RenderViewObserverHelper::DidCreateDocumentElement(blink::WebLocalFrame *frame)
+{
+    runScripts(UserScriptData::DocumentElementCreation, frame);
+}
+
+void UserScriptController::RenderViewObserverHelper::DidFinishDocumentLoad(blink::WebLocalFrame *frame)
+{
+    runScripts(UserScriptData::DocumentLoadFinished, frame);
+    m_pendingFrames.insert(frame);
+    base::MessageLoop::current()->PostDelayedTask(FROM_HERE, base::Bind(&UserScriptController::RenderViewObserverHelper::runScripts,
+                                                                        base::Unretained(this), UserScriptData::AfterLoad, frame),
+                                                  base::TimeDelta::FromMilliseconds(afterLoadTimeout));
+}
+
+void UserScriptController::RenderViewObserverHelper::DidFinishLoad(blink::WebLocalFrame *frame)
+{
+    // DidFinishDocumentLoad always comes before this, so frame has already been marked as pending.
+    base::MessageLoop::current()->PostTask(FROM_HERE, base::Bind(&UserScriptController::RenderViewObserverHelper::runScripts,
+                                                                 base::Unretained(this), UserScriptData::AfterLoad, frame));
+}
+
+void UserScriptController::RenderViewObserverHelper::DidStartProvisionalLoad(blink::WebLocalFrame *frame)
+{
+    m_pendingFrames.remove(frame);
+}
+
+void UserScriptController::RenderViewObserverHelper::FrameDetached(blink::WebFrame *frame)
+{
+    if (frame->isWebLocalFrame())
+        m_pendingFrames.remove(frame->toWebLocalFrame());
+}
+
+void UserScriptController::RenderViewObserverHelper::OnDestruct()
+{
+    UserScriptController::instance()->renderViewDestroyed(render_view());
+}
+
+bool UserScriptController::RenderViewObserverHelper::OnMessageReceived(const IPC::Message &message)
+{
+    bool handled = true;
+    IPC_BEGIN_MESSAGE_MAP(UserScriptController::RenderViewObserverHelper, message)
+        IPC_MESSAGE_HANDLER(RenderViewObserverHelper_AddScript, onUserScriptAdded)
+        IPC_MESSAGE_HANDLER(RenderViewObserverHelper_RemoveScript, onUserScriptRemoved)
+        IPC_MESSAGE_HANDLER(RenderViewObserverHelper_ClearScripts, onScriptsCleared)
+        IPC_MESSAGE_UNHANDLED(handled = false)
+    IPC_END_MESSAGE_MAP()
+            return handled;
+}
+
+void UserScriptController::RenderViewObserverHelper::onUserScriptAdded(const UserScriptData &script)
+{
+    UserScriptController::instance()->addScriptForView(script, render_view());
+}
+
+void UserScriptController::RenderViewObserverHelper::onUserScriptRemoved(const UserScriptData &script)
+{
+    UserScriptController::instance()->removeScriptForView(script, render_view());
+}
+
+void UserScriptController::RenderViewObserverHelper::onScriptsCleared()
+{
+    UserScriptController::instance()->clearScriptsForView(render_view());
+}
+
+UserScriptController *UserScriptController::instance()
+{
+    return qt_webengine_userScriptController();
+}
+
+bool UserScriptController::OnControlMessageReceived(const IPC::Message &message)
+{
+    bool handled = true;
+    IPC_BEGIN_MESSAGE_MAP(UserScriptController, message)
+        IPC_MESSAGE_HANDLER(UserScriptController_AddScript, onAddScript)
+        IPC_MESSAGE_HANDLER(UserScriptController_RemoveScript, onRemoveScript)
+        IPC_MESSAGE_HANDLER(UserScriptController_ClearScripts, onClearScripts)
+        IPC_MESSAGE_UNHANDLED(handled = false)
+    IPC_END_MESSAGE_MAP()
+    return handled;
+}
+
+UserScriptController::UserScriptController()
+{
+#if !defined(QT_NO_DEBUG) || defined(QT_FORCE_ASSERTS)
+    static bool onlyCalledOnce = true;
+    Q_ASSERT(onlyCalledOnce);
+    onlyCalledOnce = false;
+#endif // !defined(QT_NO_DEBUG) || defined(QT_FORCE_ASSERTS)
+}
+
+void UserScriptController::renderViewCreated(content::RenderView *renderView)
+{
+    // Will destroy itself with their RenderView.
+    new RenderViewObserverHelper(renderView);
+}
+
+void UserScriptController::renderViewDestroyed(content::RenderView *renderView)
+{
+    ViewUserScriptMap::iterator it = m_viewUserScriptMap.find(renderView);
+    if (it == m_viewUserScriptMap.end()) // ASSERT maybe?
+        return;
+    Q_FOREACH (uint64 id, it.value()) {
+        m_scripts.remove(id);
+    }
+    m_viewUserScriptMap.remove(renderView);
+}
+
+void UserScriptController::addScriptForView(const UserScriptData &script, content::RenderView *view)
+{
+    ViewUserScriptMap::iterator it = m_viewUserScriptMap.find(view);
+    if (it == m_viewUserScriptMap.end())
+        it = m_viewUserScriptMap.insert(view, UserScriptSet());
+
+    (*it).insert(script.scriptId);
+    m_scripts.insert(script.scriptId, script);
+}
+
+void UserScriptController::removeScriptForView(const UserScriptData &script, content::RenderView *view)
+{
+    ViewUserScriptMap::iterator it = m_viewUserScriptMap.find(view);
+    if (it == m_viewUserScriptMap.end())
+        return;
+
+    (*it).remove(script.scriptId);
+    m_scripts.remove(script.scriptId);
+}
+
+void UserScriptController::clearScriptsForView(content::RenderView *view)
+{
+    ViewUserScriptMap::iterator it = m_viewUserScriptMap.find(view);
+    if (it == m_viewUserScriptMap.end())
+        return;
+    Q_FOREACH (uint64 id, it.value())
+        m_scripts.remove(id);
+
+    m_viewUserScriptMap.remove(view);
+}
+
+void UserScriptController::onAddScript(const UserScriptData &script)
+{
+    addScriptForView(script, globalScriptsIndex);
+}
+
+void UserScriptController::onRemoveScript(const UserScriptData &script)
+{
+    removeScriptForView(script, globalScriptsIndex);
+}
+
+void UserScriptController::onClearScripts()
+{
+    clearScriptsForView(globalScriptsIndex);
+}
+
diff --git a/src/core/renderer/user_script_controller.h b/src/core/renderer/user_script_controller.h
new file mode 100644
index 000000000..ed83d9dac
--- /dev/null
+++ b/src/core/renderer/user_script_controller.h
@@ -0,0 +1,82 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see http://www.qt.io/terms-conditions. For further
+** information use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPLv3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or later as published by the Free
+** Software Foundation and appearing in the file LICENSE.GPL included in
+** the packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 2.0 requirements will be
+** met: http://www.gnu.org/licenses/gpl-2.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef USER_SCRIPT_CONTROLLER_H
+#define USER_SCRIPT_CONTROLLER_H
+
+#include "content/public/renderer/render_process_observer.h"
+
+#include "common/user_script_data.h"
+
+#include <QtCore/qcompilerdetection.h>
+#include <QtCore/QHash>
+#include <QtCore/QSet>
+
+namespace content {
+class RenderView;
+}
+
+
+class UserScriptController : public content::RenderProcessObserver {
+
+public:
+    static UserScriptController *instance();
+    UserScriptController();
+    void renderViewCreated(content::RenderView *);
+    void renderViewDestroyed(content::RenderView *);
+    void addScriptForView(const UserScriptData &, content::RenderView *);
+    void removeScriptForView(const UserScriptData &, content::RenderView *);
+    void clearScriptsForView(content::RenderView *);
+
+private:
+    Q_DISABLE_COPY(UserScriptController)
+
+    class RenderViewObserverHelper;
+
+    // RenderProcessObserver implementation.
+    virtual bool OnControlMessageReceived(const IPC::Message &message) Q_DECL_OVERRIDE;
+
+    void onAddScript(const UserScriptData &);
+    void onRemoveScript(const UserScriptData &);
+    void onClearScripts();
+
+    typedef QSet<uint64> UserScriptSet;
+    typedef QHash<const content::RenderView *, UserScriptSet> ViewUserScriptMap;
+    ViewUserScriptMap m_viewUserScriptMap;
+    QHash<uint64, UserScriptData> m_scripts;
+};
+
+#endif // USER_SCRIPT_CONTROLLER_H