/*

 * Copyright (C) 2008, 2009 Apple Inc. All rights reserved.

 * Copyright (C) 2010 Google Inc. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 *

 * 1.  Redistributions of source code must retain the above copyright

 *     notice, this list of conditions and the following disclaimer.

 * 2.  Redistributions in binary form must reproduce the above copyright

 *     notice, this list of conditions and the following disclaimer in the

 *     documentation and/or other materials provided with the distribution.

 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of

 *     its contributors may be used to endorse or promote products derived

 *     from this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY

 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include "config.h"

#include "ScriptDebugServer.h"

#if ENABLE(JAVASCRIPT_DEBUGGER)

#include "DOMWindow.h"

#include "EventLoop.h"

#include "Frame.h"

#include "FrameTree.h"

#include "FrameView.h"

#include "JSDOMWindowCustom.h"

#include "JavaScriptCallFrame.h"

#include "Page.h"

#include "PageGroup.h"

#include "PluginView.h"

#include "ScriptBreakpoint.h"

#include "ScriptController.h"

#include "ScriptDebugListener.h"

#include "ScrollView.h"

#include "Widget.h"

#include <debugger/DebuggerCallFrame.h>

#include <parser/SourceCode.h>

#include <runtime/JSLock.h>

#include <wtf/MainThread.h>

#include <wtf/StdLibExtras.h>

#include <wtf/UnusedParam.h>

using namespace JSC;

namespace WebCore {

ScriptDebugServer& ScriptDebugServer::shared()

{

    DEFINE_STATIC_LOCAL(ScriptDebugServer, server, ());

    return server;

}

ScriptDebugServer::ScriptDebugServer()

    : m_callingListeners(false)

    , m_pauseOnExceptionsState(DontPauseOnExceptions)

    , m_pauseOnNextStatement(false)

    , m_paused(false)

    , m_pausedPage(0)

    , m_doneProcessingDebuggerEvents(true)

    , m_breakpointsActivated(true)

    , m_pauseOnCallFrame(0)

    , m_recompileTimer(this, &ScriptDebugServer::recompileAllJSFunctions)

{

}

ScriptDebugServer::~ScriptDebugServer()

{

    deleteAllValues(m_pageListenersMap);

}

void ScriptDebugServer::addListener(ScriptDebugListener* listener, Page* page)

{

    ASSERT_ARG(listener, listener);

    ASSERT_ARG(page, page);

    pair<PageListenersMap::iterator, bool> result = m_pageListenersMap.add(page, 0);

    if (result.second)

        result.first->second = new ListenerSet;

    ListenerSet* listeners = result.first->second;

    listeners->add(listener);

    didAddListener(page);

}

void ScriptDebugServer::removeListener(ScriptDebugListener* listener, Page* page)

{

    ASSERT_ARG(listener, listener);

    ASSERT_ARG(page, page);

    PageListenersMap::iterator it = m_pageListenersMap.find(page);

    if (it == m_pageListenersMap.end())

        return;

    ListenerSet* listeners = it->second;

    listeners->remove(listener);

    if (listeners->isEmpty()) {

        m_pageListenersMap.remove(it);

        delete listeners;

    }

    didRemoveListener(page);

}

void ScriptDebugServer::pageCreated(Page* page)

{

    ASSERT_ARG(page, page);

    if (!hasListenersInterestedInPage(page))

        return;

    page->setDebugger(this);

}

bool ScriptDebugServer::isDebuggerAlwaysEnabled()

{

    return false;

}

bool ScriptDebugServer::hasListenersInterestedInPage(Page* page)

{

    ASSERT_ARG(page, page);

    return m_pageListenersMap.contains(page);

}

bool ScriptDebugServer::setBreakpoint(const String& sourceID, ScriptBreakpoint breakpoint, unsigned lineNumber, unsigned* actualLineNumber)

{

    intptr_t sourceIDValue = sourceID.toIntPtr();

    if (!sourceIDValue)

        return false;

    BreakpointsMap::iterator it = m_breakpoints.find(sourceIDValue);

    if (it == m_breakpoints.end())

        it = m_breakpoints.set(sourceIDValue, SourceBreakpoints()).first;

    it->second.set(lineNumber, breakpoint);

    *actualLineNumber = lineNumber;

    return true;

}

void ScriptDebugServer::removeBreakpoint(const String& sourceID, unsigned lineNumber)

{

    intptr_t sourceIDValue = sourceID.toIntPtr();

    if (!sourceIDValue)

        return;

    BreakpointsMap::iterator it = m_breakpoints.find(sourceIDValue);

    if (it != m_breakpoints.end())

        it->second.remove(lineNumber);

}

bool ScriptDebugServer::hasBreakpoint(intptr_t sourceID, unsigned lineNumber) const

{

    if (!m_breakpointsActivated)

        return false;

    BreakpointsMap::const_iterator it = m_breakpoints.find(sourceID);

    if (it == m_breakpoints.end())

        return false;

    SourceBreakpoints::const_iterator breakIt = it->second.find(lineNumber);

    if (breakIt == it->second.end() || !breakIt->second.enabled)

        return false;

    // An empty condition counts as no condition which is equivalent to "true".

    if (breakIt->second.condition.isEmpty())

        return true;

    JSValue exception;

    JSValue result = m_currentCallFrame->evaluate(stringToUString(breakIt->second.condition), exception);

    if (exception) {

        // An erroneous condition counts as "false".

        return false;

    }

    return result.toBoolean(m_currentCallFrame->scopeChain()->globalObject->globalExec());

}

void ScriptDebugServer::clearBreakpoints()

{

    m_breakpoints.clear();

}

void ScriptDebugServer::setBreakpointsActivated(bool activated)

{

    m_breakpointsActivated = activated;

}

void ScriptDebugServer::setPauseOnExceptionsState(PauseOnExceptionsState pause)

{

    m_pauseOnExceptionsState = pause;

}

void ScriptDebugServer::pause()

{

    m_pauseOnNextStatement = true;

}

void ScriptDebugServer::continueProgram()

{

    if (!m_paused)

        return;

    m_pauseOnNextStatement = false;

    m_doneProcessingDebuggerEvents = true;

}

void ScriptDebugServer::stepIntoStatement()

{

    if (!m_paused)

        return;

    m_pauseOnNextStatement = true;

    m_doneProcessingDebuggerEvents = true;

}

void ScriptDebugServer::stepOverStatement()

{

    if (!m_paused)

        return;

    m_pauseOnCallFrame = m_currentCallFrame.get();

    m_doneProcessingDebuggerEvents = true;

}

void ScriptDebugServer::stepOutOfFunction()

{

    if (!m_paused)

        return;

    m_pauseOnCallFrame = m_currentCallFrame ? m_currentCallFrame->caller() : 0;

    m_doneProcessingDebuggerEvents = true;

}

bool ScriptDebugServer::editScriptSource(const String&, const String&, String&)

{

    // FIXME(40300): implement this.

    return false;

}

JavaScriptCallFrame* ScriptDebugServer::currentCallFrame()

{

    if (!m_paused)

        return 0;

    return m_currentCallFrame.get();

}

void ScriptDebugServer::dispatchDidPause(ScriptDebugListener* listener)

{

    ASSERT(m_paused);

    ScriptState* state = m_currentCallFrame->scopeChain()->globalObject->globalExec();

    listener->didPause(state);

}

void ScriptDebugServer::dispatchDidContinue(ScriptDebugListener* listener)

{

    listener->didContinue();

}

void ScriptDebugServer::dispatchDidParseSource(const ListenerSet& listeners, const JSC::SourceCode& source, ScriptWorldType worldType)

{

    String sourceID = ustringToString(JSC::UString::from(source.provider()->asID()));

    String url = ustringToString(source.provider()->url());

    String data = ustringToString(JSC::UString(source.data(), source.length()));

    int firstLine = source.firstLine();

    Vector<ScriptDebugListener*> copy;

    copyToVector(listeners, copy);

    for (size_t i = 0; i < copy.size(); ++i)

        copy[i]->didParseSource(sourceID, url, data, firstLine, worldType);

}

void ScriptDebugServer::dispatchFailedToParseSource(const ListenerSet& listeners, const SourceCode& source, int errorLine, const String& errorMessage)

{

    String url = ustringToString(source.provider()->url());

    String data = ustringToString(JSC::UString(source.data(), source.length()));

    int firstLine = source.firstLine();

    Vector<ScriptDebugListener*> copy;

    copyToVector(listeners, copy);

    for (size_t i = 0; i < copy.size(); ++i)

        copy[i]->failedToParseSource(url, data, firstLine, errorLine, errorMessage);

}

static Page* toPage(JSGlobalObject* globalObject)

{

    ASSERT_ARG(globalObject, globalObject);

    JSDOMWindow* window = asJSDOMWindow(globalObject);

    Frame* frame = window->impl()->frame();

    return frame ? frame->page() : 0;

}

static ScriptWorldType currentWorldType(ExecState* exec)

{

    if (currentWorld(exec) == mainThreadNormalWorld())

        return MAIN_WORLD;

    return EXTENSIONS_WORLD;

}

void ScriptDebugServer::detach(JSGlobalObject* globalObject)

{

    // If we're detaching from the currently executing global object, manually tear down our

    // stack, since we won't get further debugger callbacks to do so. Also, resume execution,

    // since there's no point in staying paused once a window closes.

    if (m_currentCallFrame && m_currentCallFrame->dynamicGlobalObject() == globalObject) {

        m_currentCallFrame = 0;

        m_pauseOnCallFrame = 0;

        continueProgram();

    }

    Debugger::detach(globalObject);

}

void ScriptDebugServer::sourceParsed(ExecState* exec, const SourceCode& source, int errorLine, const UString& errorMessage)

{

    if (m_callingListeners)

        return;

    Page* page = toPage(exec->lexicalGlobalObject());

    if (!page)

        return;

    ScriptWorldType worldType = currentWorldType(exec);

    m_callingListeners = true;

    bool isError = errorLine != -1;

    if (ListenerSet* pageListeners = m_pageListenersMap.get(page)) {

        ASSERT(!pageListeners->isEmpty());

        if (isError)

            dispatchFailedToParseSource(*pageListeners, source, errorLine, ustringToString(errorMessage));

        else

            dispatchDidParseSource(*pageListeners, source, worldType);

    }

    m_callingListeners = false;

}

void ScriptDebugServer::dispatchFunctionToListeners(const ListenerSet& listeners, JavaScriptExecutionCallback callback)

{

    Vector<ScriptDebugListener*> copy;

    copyToVector(listeners, copy);

    for (size_t i = 0; i < copy.size(); ++i)

        (this->*callback)(copy[i]);

}

void ScriptDebugServer::dispatchFunctionToListeners(JavaScriptExecutionCallback callback, Page* page)

{

    if (m_callingListeners)

        return;

    m_callingListeners = true;

    if (ListenerSet* pageListeners = m_pageListenersMap.get(page)) {

        ASSERT(!pageListeners->isEmpty());

        dispatchFunctionToListeners(*pageListeners, callback);

    }

    m_callingListeners = false;

}

void ScriptDebugServer::setJavaScriptPaused(const PageGroup& pageGroup, bool paused)

{

    setMainThreadCallbacksPaused(paused);

    const HashSet<Page*>& pages = pageGroup.pages();

    HashSet<Page*>::const_iterator end = pages.end();

    for (HashSet<Page*>::const_iterator it = pages.begin(); it != end; ++it)

        setJavaScriptPaused(*it, paused);

}

void ScriptDebugServer::setJavaScriptPaused(Page* page, bool paused)

{

    ASSERT_ARG(page, page);

    page->setDefersLoading(paused);

    for (Frame* frame = page->mainFrame(); frame; frame = frame->tree()->traverseNext())

        setJavaScriptPaused(frame, paused);

}

void ScriptDebugServer::setJavaScriptPaused(Frame* frame, bool paused)

{

    ASSERT_ARG(frame, frame);

    if (!frame->script()->canExecuteScripts(NotAboutToExecuteScript))

        return;

    frame->script()->setPaused(paused);

    Document* document = frame->document();

    if (paused)

        document->suspendActiveDOMObjects();

    else

        document->resumeActiveDOMObjects();

    setJavaScriptPaused(frame->view(), paused);

}

void ScriptDebugServer::setJavaScriptPaused(FrameView* view, bool paused)

{

    if (!view)

        return;

    const HashSet<RefPtr<Widget> >* children = view->children();

    ASSERT(children);

    HashSet<RefPtr<Widget> >::const_iterator end = children->end();

    for (HashSet<RefPtr<Widget> >::const_iterator it = children->begin(); it != end; ++it) {

        Widget* widget = (*it).get();

        if (!widget->isPluginView())

            continue;

        static_cast<PluginView*>(widget)->setJavaScriptPaused(paused);

    }

}

void ScriptDebugServer::pauseIfNeeded(Page* page)

{

    if (m_paused)

        return;

    if (!page || !hasListenersInterestedInPage(page))

        return;

    bool pauseNow = m_pauseOnNextStatement;

    pauseNow |= (m_pauseOnCallFrame == m_currentCallFrame);

    pauseNow |= (m_currentCallFrame->line() > 0 && hasBreakpoint(m_currentCallFrame->sourceID(), m_currentCallFrame->line()));

    if (!pauseNow)

        return;

    m_pauseOnCallFrame = 0;

    m_pauseOnNextStatement = false;

    m_paused = true;

    m_pausedPage = page;

    dispatchFunctionToListeners(&ScriptDebugServer::dispatchDidPause, page);

    setJavaScriptPaused(page->group(), true);

    TimerBase::fireTimersInNestedEventLoop();

    EventLoop loop;

    m_doneProcessingDebuggerEvents = false;

    while (!m_doneProcessingDebuggerEvents && !loop.ended())

        loop.cycle();

    setJavaScriptPaused(page->group(), false);

    m_paused = false;

    m_pausedPage = 0;

    dispatchFunctionToListeners(&ScriptDebugServer::dispatchDidContinue, page);

}

void ScriptDebugServer::callEvent(const DebuggerCallFrame& debuggerCallFrame, intptr_t sourceID, int lineNumber)

{

    if (m_paused)

        return;

    m_currentCallFrame = JavaScriptCallFrame::create(debuggerCallFrame, m_currentCallFrame, sourceID, lineNumber);

    pauseIfNeeded(toPage(debuggerCallFrame.dynamicGlobalObject()));

}

void ScriptDebugServer::atStatement(const DebuggerCallFrame& debuggerCallFrame, intptr_t sourceID, int lineNumber)

{

    if (m_paused)

        return;

    ASSERT(m_currentCallFrame);

    if (!m_currentCallFrame)

        return;

    m_currentCallFrame->update(debuggerCallFrame, sourceID, lineNumber);

    pauseIfNeeded(toPage(debuggerCallFrame.dynamicGlobalObject()));

}

void ScriptDebugServer::returnEvent(const DebuggerCallFrame& debuggerCallFrame, intptr_t sourceID, int lineNumber)

{

    if (m_paused)

        return;

    ASSERT(m_currentCallFrame);

    if (!m_currentCallFrame)

        return;

    m_currentCallFrame->update(debuggerCallFrame, sourceID, lineNumber);

    pauseIfNeeded(toPage(debuggerCallFrame.dynamicGlobalObject()));

    // Treat stepping over a return statement like stepping out.

    if (m_currentCallFrame == m_pauseOnCallFrame)

        m_pauseOnCallFrame = m_currentCallFrame->caller();

    m_currentCallFrame = m_currentCallFrame->caller();

}

void ScriptDebugServer::exception(const DebuggerCallFrame& debuggerCallFrame, intptr_t sourceID, int lineNumber, bool hasHandler)

{

    if (m_paused)

        return;

    ASSERT(m_currentCallFrame);

    if (!m_currentCallFrame)

        return;

    if (m_pauseOnExceptionsState == PauseOnAllExceptions || (m_pauseOnExceptionsState == PauseOnUncaughtExceptions && !hasHandler))

        m_pauseOnNextStatement = true;

    m_currentCallFrame->update(debuggerCallFrame, sourceID, lineNumber);

    pauseIfNeeded(toPage(debuggerCallFrame.dynamicGlobalObject()));

}

void ScriptDebugServer::willExecuteProgram(const DebuggerCallFrame& debuggerCallFrame, intptr_t sourceID, int lineNumber)

{

    if (m_paused)

        return;

    m_currentCallFrame = JavaScriptCallFrame::create(debuggerCallFrame, m_currentCallFrame, sourceID, lineNumber);

    pauseIfNeeded(toPage(debuggerCallFrame.dynamicGlobalObject()));