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#include "evaluator.h"

#include "evaluationdata.h"
#include "evaluatorscriptclass.h"
#include "filecontext.h"
#include "filetags.h"
#include "item.h"
#include "scriptengine.h"
#include "value.h"

#include <buildgraph/buildgraph.h>
#include <jsextensions/jsextensions.h>
#include <logging/translator.h>
#include <tools/error.h>
#include <tools/scripttools.h>
#include <tools/qbsassert.h>
#include <tools/qttools.h>
#include <tools/stringconstants.h>

#include <QtCore/qdebug.h>

namespace qbs {
namespace Internal {

Evaluator::Evaluator(ScriptEngine *scriptEngine)
    : m_scriptEngine(scriptEngine)
    , m_scriptClass(new EvaluatorScriptClass(scriptEngine))
{
}

Evaluator::~Evaluator()
{
    for (const auto &data : qAsConst(m_scriptValueMap))
        delete attachedPointer<EvaluationData>(data);
    delete m_scriptClass;
}

QScriptValue Evaluator::property(const Item *item, const QString &name)
{
    return scriptValue(item).property(name);
}

QScriptValue Evaluator::value(const Item *item, const QString &name, bool *propertyWasSet)
{
    QScriptValue v;
    evaluateProperty(&v, item, name, propertyWasSet);
    return v;
}

bool Evaluator::boolValue(const Item *item, const QString &name,
                          bool *propertyWasSet)
{
    return value(item, name, propertyWasSet).toBool();
}

int Evaluator::intValue(const Item *item, const QString &name, int defaultValue,
                        bool *propertyWasSet)
{
    QScriptValue v;
    if (!evaluateProperty(&v, item, name, propertyWasSet))
        return defaultValue;
    return v.toInt32();
}

FileTags Evaluator::fileTagsValue(const Item *item, const QString &name, bool *propertySet)
{
    return FileTags::fromStringList(stringListValue(item, name, propertySet));
}

QString Evaluator::stringValue(const Item *item, const QString &name,
                               const QString &defaultValue, bool *propertyWasSet)
{
    QScriptValue v;
    if (!evaluateProperty(&v, item, name, propertyWasSet))
        return defaultValue;
    return v.toString();
}

static QStringList toStringList(const QScriptValue &scriptValue)
{
    if (scriptValue.isString()) {
        return QStringList(scriptValue.toString());
    } else if (scriptValue.isArray()) {
        QStringList lst;
        int i = 0;
        forever {
            QScriptValue elem = scriptValue.property(i++);
            if (!elem.isValid())
                break;
            lst.push_back(elem.toString());
        }
        return lst;
    }
    return QStringList();
}

QStringList Evaluator::stringListValue(const Item *item, const QString &name, bool *propertyWasSet)
{
    QScriptValue v = property(item, name);
    handleEvaluationError(item, name, v);
    if (propertyWasSet)
        *propertyWasSet = isNonDefaultValue(item, name);
    return toStringList(v);
}

bool Evaluator::isNonDefaultValue(const Item *item, const QString &name) const
{
    const ValueConstPtr v = item->property(name);
    return v && (v->type() != Value::JSSourceValueType
                 || !static_cast<const JSSourceValue *>(v.get())->isBuiltinDefaultValue());
}

void Evaluator::convertToPropertyType(const PropertyDeclaration &decl, const CodeLocation &loc,
                                      QScriptValue &v)
{
    m_scriptClass->convertToPropertyType(decl, loc, v);
}

QScriptValue Evaluator::scriptValue(const Item *item)
{
    QScriptValue &scriptValue = m_scriptValueMap[item];
    if (scriptValue.isObject()) {
        // already initialized
        return scriptValue;
    }

    auto edata = new EvaluationData;
    edata->evaluator = this;
    edata->item = item;
    edata->item->setObserver(this);

    scriptValue = m_scriptEngine->newObject(m_scriptClass);
    attachPointerTo(scriptValue, edata);
    return scriptValue;
}

void Evaluator::onItemPropertyChanged(Item *item)
{
    EvaluationData *data = attachedPointer<EvaluationData>(m_scriptValueMap.value(item));
    if (data)
        data->valueCache.clear();
}

void Evaluator::handleEvaluationError(const Item *item, const QString &name,
        const QScriptValue &scriptValue)
{
    throwOnEvaluationError(m_scriptEngine, scriptValue, [&item, &name] () {
        const ValueConstPtr &value = item->property(name);
        return value ? value->location() : CodeLocation();
    });
}

void Evaluator::setPathPropertiesBaseDir(const QString &dirPath)
{
    m_scriptClass->setPathPropertiesBaseDir(dirPath);
}

void Evaluator::clearPathPropertiesBaseDir()
{
    m_scriptClass->clearPathPropertiesBaseDir();
}

bool Evaluator::evaluateProperty(QScriptValue *result, const Item *item, const QString &name,
        bool *propertyWasSet)
{
    *result = property(item, name);
    handleEvaluationError(item, name, *result);
    if (propertyWasSet)
        *propertyWasSet = isNonDefaultValue(item, name);
    return result->isValid() && !result->isUndefined();
}

Evaluator::FileContextScopes Evaluator::fileContextScopes(const FileContextConstPtr &file)
{
    FileContextScopes &result = m_fileContextScopesMap[file];
    if (!result.fileScope.isObject()) {
        if (file->idScope())
            result.fileScope = scriptValue(file->idScope());
        else
            result.fileScope = m_scriptEngine->newObject();
        result.fileScope.setProperty(StringConstants::filePathGlobalVar(), file->filePath());
        result.fileScope.setProperty(StringConstants::pathGlobalVar(), file->dirPath());
    }
    if (!result.importScope.isObject()) {
        try {
            result.importScope = m_scriptEngine->newObject();
            setupScriptEngineForFile(m_scriptEngine, file, result.importScope,
                                     ObserveMode::Enabled);
        } catch (const ErrorInfo &e) {
            result.importScope = m_scriptEngine->currentContext()->throwError(e.toString());
        }
    }
    return result;
}

void Evaluator::setCachingEnabled(bool enabled)
{
    m_scriptClass->setValueCacheEnabled(enabled);
}

PropertyDependencies Evaluator::propertyDependencies() const
{
    return m_scriptClass->propertyDependencies();
}

void Evaluator::clearPropertyDependencies()
{
    m_scriptClass->clearPropertyDependencies();
}

void throwOnEvaluationError(ScriptEngine *engine, const QScriptValue &scriptValue,
                            const std::function<CodeLocation()> &provideFallbackCodeLocation)
{
    if (Q_LIKELY(!engine->hasErrorOrException(scriptValue)))
        return;
    QString message;
    QString filePath;
    int line = -1;
    const QScriptValue value = scriptValue.isError() ? scriptValue
                                                     : engine->uncaughtException();
    if (value.isError()) {
        QScriptValue v = value.property(QStringLiteral("message"));
        if (v.isString())
            message = v.toString();
        v = value.property(StringConstants::fileNameProperty());
        if (v.isString())
            filePath = v.toString();
        v = value.property(QStringLiteral("lineNumber"));
        if (v.isNumber())
            line = v.toInt32();
        throw ErrorInfo(message, CodeLocation(filePath, line, -1, false));
    } else {
        message = value.toString();
        throw ErrorInfo(message, provideFallbackCodeLocation());
    }
}

} // namespace Internal
} // namespace qbs