/*

 * 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:

 *

 *     * Redistributions of source code must retain the above copyright

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

 *     * 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.

 *     * Neither the name of Google Inc. 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 THE COPYRIGHT HOLDERS AND 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 THE COPYRIGHT

 * OWNER OR 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 "Frame.h"

#include "JavaScriptCallFrame.h"

#include "Page.h"

#include "ScriptDebugListener.h"

#include "V8Binding.h"

#include "V8DOMWindow.h"

#include "V8Proxy.h"

#include <wtf/StdLibExtras.h>

namespace WebCore {

static Frame* retrieveFrame(v8::Handle<v8::Context> context)

{

    if (context.IsEmpty())

        return 0;

    // Test that context has associated global dom window object.

    v8::Handle<v8::Object> global = context->Global();

    if (global.IsEmpty())

        return 0;

    global = V8DOMWrapper::lookupDOMWrapper(V8DOMWindow::GetTemplate(), global);

    if (global.IsEmpty())

        return 0;

    return V8Proxy::retrieveFrame(context);

}

ScriptDebugServer& ScriptDebugServer::shared()

{

    DEFINE_STATIC_LOCAL(ScriptDebugServer, server, ());

    return server;

}

ScriptDebugServer::ScriptDebugServer()

    : m_pauseOnExceptionsState(DontPauseOnExceptions)

    , m_pausedPage(0)

    , m_enabled(true)

{

}

void ScriptDebugServer::setDebuggerScriptSource(const String& scriptSource)

{

    m_debuggerScriptSource = scriptSource;

}

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

{

    if (!m_enabled)

        return;

    V8Proxy* proxy = V8Proxy::retrieve(page->mainFrame());

    if (!proxy)

        return;

    v8::HandleScope scope;

    v8::Local<v8::Context> debuggerContext = v8::Debug::GetDebugContext();

    v8::Context::Scope contextScope(debuggerContext);

    if (!m_listenersMap.size()) {

        ensureDebuggerScriptCompiled();

        ASSERT(!m_debuggerScript.get()->IsUndefined());

        v8::Debug::SetDebugEventListener2(&ScriptDebugServer::v8DebugEventCallback);

    }

    m_listenersMap.set(page, listener);

    v8::Local<v8::Context> context = proxy->mainWorldContext();

    v8::Handle<v8::Function> getScriptsFunction = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("getScripts")));

    v8::Handle<v8::Value> argv[] = { context->GetData() };

    v8::Handle<v8::Value> value = getScriptsFunction->Call(m_debuggerScript.get(), 1, argv);

    if (value.IsEmpty())

        return;

    ASSERT(!value->IsUndefined() && value->IsArray());

    v8::Handle<v8::Array> scriptsArray = v8::Handle<v8::Array>::Cast(value);

    for (unsigned i = 0; i < scriptsArray->Length(); ++i)

        dispatchDidParseSource(listener, v8::Handle<v8::Object>::Cast(scriptsArray->Get(v8::Integer::New(i))));

}

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

{

    if (!m_listenersMap.contains(page))

        return;

    if (m_pausedPage == page)

        continueProgram();

    m_listenersMap.remove(page);

    if (m_listenersMap.isEmpty())

        v8::Debug::SetDebugEventListener(0);

    // FIXME: Remove all breakpoints set by the agent.

}

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

{

    v8::HandleScope scope;

    v8::Local<v8::Context> debuggerContext = v8::Debug::GetDebugContext();

    v8::Context::Scope contextScope(debuggerContext);

    v8::Local<v8::Object> args = v8::Object::New();

    args->Set(v8::String::New("scriptId"), v8String(sourceID));

    args->Set(v8::String::New("lineNumber"), v8::Integer::New(lineNumber));

    args->Set(v8::String::New("condition"), v8String(breakpoint.condition));

    args->Set(v8::String::New("enabled"), v8::Boolean::New(breakpoint.enabled));

    v8::Handle<v8::Function> setBreakpointFunction = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("setBreakpoint")));

    v8::Handle<v8::Value> result = v8::Debug::Call(setBreakpointFunction, args);

    if (!result->IsNumber())

        return false;

    ASSERT(result->Int32Value() >= 0);

    *actualLineNumber = result->Int32Value();

    return true;

}

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

{

    v8::HandleScope scope;

    v8::Local<v8::Context> debuggerContext = v8::Debug::GetDebugContext();

    v8::Context::Scope contextScope(debuggerContext);

    v8::Local<v8::Object> args = v8::Object::New();

    args->Set(v8::String::New("scriptId"), v8String(sourceID));

    args->Set(v8::String::New("lineNumber"), v8::Integer::New(lineNumber));

    v8::Handle<v8::Function> removeBreakpointFunction = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("removeBreakpoint")));

    v8::Debug::Call(removeBreakpointFunction, args);

}

void ScriptDebugServer::clearBreakpoints()

{

    ensureDebuggerScriptCompiled();

    v8::HandleScope scope;

    v8::Local<v8::Context> debuggerContext = v8::Debug::GetDebugContext();

    v8::Context::Scope contextScope(debuggerContext);

    v8::Handle<v8::Function> clearBreakpoints = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("clearBreakpoints")));

    v8::Debug::Call(clearBreakpoints);

}

void ScriptDebugServer::setBreakpointsActivated(bool enabled)

{

    ensureDebuggerScriptCompiled();

    v8::HandleScope scope;

    v8::Local<v8::Context> debuggerContext = v8::Debug::GetDebugContext();

    v8::Context::Scope contextScope(debuggerContext);

    v8::Local<v8::Object> args = v8::Object::New();

    args->Set(v8::String::New("enabled"), v8::Boolean::New(enabled));

    v8::Handle<v8::Function> setBreakpointsActivated = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("setBreakpointsActivated")));

    v8::Debug::Call(setBreakpointsActivated, args);

}

ScriptDebugServer::PauseOnExceptionsState ScriptDebugServer::pauseOnExceptionsState()

{

    ensureDebuggerScriptCompiled();

    v8::HandleScope scope;

    v8::Context::Scope contextScope(v8::Debug::GetDebugContext());

    v8::Handle<v8::Function> function = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("pauseOnExceptionsState")));

    v8::Handle<v8::Value> argv[] = { v8::Handle<v8::Value>() };

    v8::Handle<v8::Value> result = function->Call(m_debuggerScript.get(), 0, argv);

    return static_cast<ScriptDebugServer::PauseOnExceptionsState>(result->Int32Value());

}

void ScriptDebugServer::setPauseOnExceptionsState(PauseOnExceptionsState pauseOnExceptionsState)

{

    ensureDebuggerScriptCompiled();

    v8::HandleScope scope;

    v8::Context::Scope contextScope(v8::Debug::GetDebugContext());

    v8::Handle<v8::Function> setPauseOnExceptionsFunction = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("setPauseOnExceptionsState")));

    v8::Handle<v8::Value> argv[] = { v8::Int32::New(pauseOnExceptionsState) };

    setPauseOnExceptionsFunction->Call(m_debuggerScript.get(), 1, argv);

}

void ScriptDebugServer::continueProgram()

{

    if (m_pausedPage)

        m_clientMessageLoop->quitNow();

    didResume();

}

void ScriptDebugServer::stepIntoStatement()

{

    ASSERT(m_pausedPage);

    v8::Handle<v8::Function> function = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("stepIntoStatement")));

    v8::Handle<v8::Value> argv[] = { m_executionState.get() };

    function->Call(m_debuggerScript.get(), 1, argv);

    continueProgram();

}

void ScriptDebugServer::stepOverStatement()

{

    ASSERT(m_pausedPage);

    v8::Handle<v8::Function> function = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("stepOverStatement")));

    v8::Handle<v8::Value> argv[] = { m_executionState.get() };

    function->Call(m_debuggerScript.get(), 1, argv);

    continueProgram();

}

void ScriptDebugServer::stepOutOfFunction()

{

    ASSERT(m_pausedPage);

    v8::Handle<v8::Function> function = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("stepOutOfFunction")));

    v8::Handle<v8::Value> argv[] = { m_executionState.get() };

    function->Call(m_debuggerScript.get(), 1, argv);

    continueProgram();

}

bool ScriptDebugServer::editScriptSource(const String& sourceID, const String& newContent, String& newSourceOrErrorMessage)

{

    ensureDebuggerScriptCompiled();

    v8::HandleScope scope;

    OwnPtr<v8::Context::Scope> contextScope;

    if (!m_pausedPage)

        contextScope.set(new v8::Context::Scope(v8::Debug::GetDebugContext()));

    v8::Handle<v8::Function> function = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("editScriptSource")));

    v8::Handle<v8::Value> argv[] = { v8String(sourceID), v8String(newContent) };

    v8::TryCatch tryCatch;

    tryCatch.SetVerbose(false);

    v8::Handle<v8::Value> result = function->Call(m_debuggerScript.get(), 2, argv);

    if (tryCatch.HasCaught()) {

        v8::Local<v8::Message> message = tryCatch.Message();

        if (!message.IsEmpty())

            newSourceOrErrorMessage = toWebCoreStringWithNullOrUndefinedCheck(message->Get());

        return false;

    }

    ASSERT(!result.IsEmpty());

    newSourceOrErrorMessage = toWebCoreStringWithNullOrUndefinedCheck(result);

    // Call stack may have changed after if the edited function was on the stack.

    if (m_currentCallFrame)

        m_currentCallFrame.clear();

    return true;

}

PassRefPtr<JavaScriptCallFrame> ScriptDebugServer::currentCallFrame()

{

    if (!m_currentCallFrame) {

        v8::Handle<v8::Function> currentCallFrameFunction = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("currentCallFrame")));

        v8::Handle<v8::Value> argv[] = { m_executionState.get() };

        v8::Handle<v8::Value> currentCallFrameV8 = currentCallFrameFunction->Call(m_debuggerScript.get(), 1, argv);

        m_currentCallFrame = JavaScriptCallFrame::create(v8::Debug::GetDebugContext(), v8::Handle<v8::Object>::Cast(currentCallFrameV8));

    }

    return m_currentCallFrame;

}

void ScriptDebugServer::setEnabled(bool value)

{

     m_enabled = value;

}

bool ScriptDebugServer::isDebuggerAlwaysEnabled()

{

    return m_enabled;

}

void ScriptDebugServer::v8DebugEventCallback(const v8::Debug::EventDetails& eventDetails)

{

    ScriptDebugServer::shared().handleV8DebugEvent(eventDetails);

}

void ScriptDebugServer::handleV8DebugEvent(const v8::Debug::EventDetails& eventDetails)

{

    v8::DebugEvent event = eventDetails.GetEvent();

    if (event != v8::Break && event != v8::Exception && event != v8::AfterCompile)

        return;

    v8::Handle<v8::Context> eventContext = eventDetails.GetEventContext();

    ASSERT(!eventContext.IsEmpty());

    Frame* frame = retrieveFrame(eventContext);

    if (frame) {

        ScriptDebugListener* listener = m_listenersMap.get(frame->page());

        if (listener) {

            v8::HandleScope scope;

            if (event == v8::AfterCompile) {

                v8::Context::Scope contextScope(v8::Debug::GetDebugContext());

                v8::Handle<v8::Function> onAfterCompileFunction = v8::Local<v8::Function>::Cast(m_debuggerScript.get()->Get(v8::String::New("getAfterCompileScript")));

                v8::Handle<v8::Value> argv[] = { eventDetails.GetEventData() };

                v8::Handle<v8::Value> value = onAfterCompileFunction->Call(m_debuggerScript.get(), 1, argv);

                ASSERT(value->IsObject());

                v8::Handle<v8::Object> object = v8::Handle<v8::Object>::Cast(value);

                dispatchDidParseSource(listener, object);

            } else if (event == v8::Break || event == v8::Exception) {

                if (event == v8::Exception) {

                    v8::Local<v8::StackTrace> stackTrace = v8::StackTrace::CurrentStackTrace(1);

                    // Stack trace is empty in case of syntax error. Silently continue execution in such cases.

                    if (!stackTrace->GetFrameCount())

                        return;

                }

                // Don't allow nested breaks.

                if (m_pausedPage)

                    return;

                m_executionState.set(eventDetails.GetExecutionState());

                m_pausedPage = frame->page();

                ScriptState* currentCallFrameState = mainWorldScriptState(frame);

                listener->didPause(currentCallFrameState);

                // Wait for continue or step command.

                m_clientMessageLoop->run(m_pausedPage);

                ASSERT(!m_pausedPage);

                // The listener may have been removed in the nested loop.

                if (ScriptDebugListener* listener = m_listenersMap.get(frame->page()))

                    listener->didContinue();

            }

        }

    }

}

void ScriptDebugServer::dispatchDidParseSource(ScriptDebugListener* listener, v8::Handle<v8::Object> object)

{

    listener->didParseSource(

        toWebCoreStringWithNullOrUndefinedCheck(object->Get(v8::String::New("id"))),

        toWebCoreStringWithNullOrUndefinedCheck(object->Get(v8::String::New("name"))),

        toWebCoreStringWithNullOrUndefinedCheck(object->Get(v8::String::New("source"))),

        object->Get(v8::String::New("lineOffset"))->ToInteger()->Value(),

        static_cast<ScriptWorldType>(object->Get(v8::String::New("scriptWorldType"))->Int32Value()));

}

void ScriptDebugServer::ensureDebuggerScriptCompiled()

{

    if (m_debuggerScript.get().IsEmpty()) {

        v8::HandleScope scope;

        v8::Local<v8::Context> debuggerContext = v8::Debug::GetDebugContext();

        v8::Context::Scope contextScope(debuggerContext);

        m_debuggerScript.set(v8::Handle<v8::Object>::Cast(v8::Script::Compile(v8String(m_debuggerScriptSource))->Run()));

    }

}

void ScriptDebugServer::didResume()

{

    m_currentCallFrame.clear();

    m_executionState.clear();

    m_pausedPage = 0;

}

} // namespace WebCore

#endif // ENABLE(JAVASCRIPT_DEBUGGER)