/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * 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.
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 * 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,
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 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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#include "config.h"
#include "bindings/core/v8/ScriptPreprocessor.h"

#include "bindings/core/v8/ScriptController.h"
#include "bindings/core/v8/ScriptSourceCode.h"
#include "bindings/core/v8/ScriptValue.h"
#include "bindings/core/v8/V8Binding.h"
#include "bindings/core/v8/V8ScriptRunner.h"
#include "core/frame/FrameConsole.h"
#include "core/frame/FrameHost.h"
#include "core/frame/LocalFrame.h"
#include "wtf/TemporaryChange.h"

namespace WebCore {

ScriptPreprocessor::ScriptPreprocessor(const ScriptSourceCode& preprocessorSourceCode, LocalFrame* frame)
    : m_isPreprocessing(false)
{
    RefPtr<DOMWrapperWorld> world = DOMWrapperWorld::ensureIsolatedWorld(ScriptPreprocessorIsolatedWorldId, DOMWrapperWorld::mainWorldExtensionGroup);
    m_scriptState = ScriptState::from(toV8Context(frame, *world));

    v8::HandleScope handleScope(m_scriptState->isolate());
    ASSERT(frame);
    v8::TryCatch tryCatch;
    tryCatch.SetVerbose(true);
    Vector<ScriptSourceCode> sources;
    sources.append(preprocessorSourceCode);
    Vector<v8::Local<v8::Value> > scriptResults;
    frame->script().executeScriptInIsolatedWorld(ScriptPreprocessorIsolatedWorldId, sources, DOMWrapperWorld::mainWorldExtensionGroup, &scriptResults);

    if (scriptResults.size() != 1) {
        frame->console().addMessage(JSMessageSource, ErrorMessageLevel, "ScriptPreprocessor internal error, one ScriptSourceCode must give exactly one result.");
        return;
    }

    v8::Local<v8::Value> preprocessorFunction = scriptResults[0];
    if (preprocessorFunction.IsEmpty() || !preprocessorFunction->IsFunction()) {
        frame->console().addMessage(JSMessageSource, ErrorMessageLevel, "The preprocessor must compile to a function.");
        return;
    }
    m_preprocessorFunction.set(m_scriptState->isolate(), v8::Handle<v8::Function>::Cast(preprocessorFunction));
}

String ScriptPreprocessor::preprocessSourceCode(const String& sourceCode, const String& sourceName)
{
    if (!isValid())
        return sourceCode;

    return preprocessSourceCode(sourceCode, sourceName, v8::Undefined(m_scriptState->isolate()));
}

String ScriptPreprocessor::preprocessSourceCode(const String& sourceCode, const String& sourceName, const String& functionName)
{
    if (!isValid())
        return sourceCode;

    v8::Handle<v8::String> functionNameString = v8String(m_scriptState->isolate(), functionName);
    return preprocessSourceCode(sourceCode, sourceName, functionNameString);
}

String ScriptPreprocessor::preprocessSourceCode(const String& sourceCode, const String& sourceName, v8::Handle<v8::Value> functionName)
{
    if (!isValid())
        return sourceCode;

    v8::Isolate* isolate = m_scriptState->isolate();
    ScriptState::Scope scope(m_scriptState.get());

    v8::Handle<v8::String> sourceCodeString = v8String(isolate, sourceCode);
    v8::Handle<v8::String> sourceNameString = v8String(isolate, sourceName);
    v8::Handle<v8::Value> argv[] = { sourceCodeString, sourceNameString, functionName};

    v8::TryCatch tryCatch;
    tryCatch.SetVerbose(true);
    TemporaryChange<bool> isPreprocessing(m_isPreprocessing, true);
    v8::Handle<v8::Value> resultValue = V8ScriptRunner::callAsFunction(isolate, m_preprocessorFunction.newLocal(isolate), m_scriptState->context()->Global(), WTF_ARRAY_LENGTH(argv), argv);

    if (!resultValue.IsEmpty() && resultValue->IsString())
        return toCoreStringWithNullCheck(resultValue.As<v8::String>());

    return sourceCode;
}

} // namespace WebCore