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**
** Copyright (C) 2019 The Qt Company Ltd.
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** This file is part of the tools applications of the Qt Toolkit.
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** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
** included in the packaging of this file. Please review the following
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#include "qqmljsimportvisitor_p.h"

#include <QtCore/qfileinfo.h>
#include <QtCore/qdir.h>
#include <QtCore/qqueue.h>

QT_BEGIN_NAMESPACE

using namespace QQmlJS::AST;

QQmlJSImportVisitor::QQmlJSImportVisitor(
        QQmlJSImporter *importer, const QString &implicitImportDirectory,
        const QStringList &qmltypesFiles)
    : m_implicitImportDirectory(implicitImportDirectory)
    , m_qmltypesFiles(qmltypesFiles)
    , m_currentScope(QQmlJSScope::create(QQmlJSScope::JSFunctionScope))
    , m_importer(importer)
{
    m_globalScope = m_currentScope;
}

void QQmlJSImportVisitor::enterEnvironment(QQmlJSScope::ScopeType type, const QString &name,
                                           const QQmlJS::SourceLocation &location)
{
    m_currentScope = QQmlJSScope::create(type, m_currentScope);
    if (type == QQmlJSScope::GroupedPropertyScope)
        m_currentScope->setInternalName(name);
    else
        m_currentScope->setBaseTypeName(name);
    m_currentScope->setIsComposite(true);
    m_currentScope->setSourceLocation(location);
}

void QQmlJSImportVisitor::leaveEnvironment()
{
    m_currentScope = m_currentScope->parentScope();
}

void QQmlJSImportVisitor::resolveAliases()
{
    QQueue<QQmlJSScope::Ptr> objects;
    objects.enqueue(m_qmlRootScope);

    while (!objects.isEmpty()) {
        const QQmlJSScope::Ptr object = objects.dequeue();
        const auto properties = object->ownProperties();
        for (auto property : properties) {
            if (!property.isAlias())
                continue;
            const auto it = m_scopesById.find(property.typeName());
            if (it != m_scopesById.end()) {
                property.setType(QQmlJSScope::ConstPtr(*it));
                object->addOwnProperty(property);
            }
        }

        const auto childScopes = object->childScopes();
        for (const auto &childScope : childScopes)
            objects.enqueue(childScope);
    }
}

QQmlJSScope::Ptr QQmlJSImportVisitor::result() const
{
    return m_qmlRootScope;
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::UiProgram *)
{
    m_rootScopeImports = m_importer->importBuiltins();

    if (!m_qmltypesFiles.isEmpty())
        m_rootScopeImports.insert(m_importer->importQmltypes(m_qmltypesFiles));

    m_rootScopeImports.insert(m_importer->importDirectory(m_implicitImportDirectory));

    m_errors.append(m_importer->takeWarnings());
    return true;
}

void QQmlJSImportVisitor::endVisit(UiProgram *)
{
    resolveAliases();
}

bool QQmlJSImportVisitor::visit(UiObjectDefinition *definition)
{
    QString superType;
    for (auto segment = definition->qualifiedTypeNameId; segment; segment = segment->next) {
        if (!superType.isEmpty())
            superType.append(u'.');
        superType.append(segment->name.toString());
    }
    enterEnvironment(QQmlJSScope::QMLScope, superType, definition->firstSourceLocation());
    if (!m_qmlRootScope)
        m_qmlRootScope = m_currentScope;

    m_currentScope->resolveTypes(m_rootScopeImports);
    return true;
}

void QQmlJSImportVisitor::endVisit(UiObjectDefinition *)
{
    m_currentScope->resolveGroupedScopes();
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(UiPublicMember *publicMember)
{
    switch (publicMember->type) {
    case UiPublicMember::Signal: {
        UiParameterList *param = publicMember->parameters;
        QQmlJSMetaMethod method;
        method.setMethodType(QQmlJSMetaMethod::Signal);
        method.setMethodName(publicMember->name.toString());
        while (param) {
            method.addParameter(param->name.toString(), param->type->name.toString());
            param = param->next;
        }
        m_currentScope->addOwnMethod(method);
        break;
    }
    case UiPublicMember::Property: {
        auto typeName = publicMember->memberType
                ? publicMember->memberType->name
                : QStringView();
        const bool isAlias = (typeName == QLatin1String("alias"));
        if (isAlias) {
            const auto expression = cast<ExpressionStatement *>(publicMember->statement);
            if (const auto idExpression = cast<IdentifierExpression *>(expression->expression))
                typeName = idExpression->name;
        }
        QQmlJSMetaProperty prop;
        prop.setPropertyName(publicMember->name.toString());
        prop.setTypeName(typeName.toString());
        prop.setIsList(publicMember->typeModifier == QLatin1String("list"));
        prop.setIsWritable(!publicMember->isReadonlyMember);
        prop.setIsAlias(isAlias);
        prop.setType(m_rootScopeImports.value(prop.typeName()));
        m_currentScope->insertPropertyIdentifier(prop);
        break;
    }
    }
    return true;
}

void QQmlJSImportVisitor::visitFunctionExpressionHelper(QQmlJS::AST::FunctionExpression *fexpr)
{
    using namespace QQmlJS::AST;
    auto name = fexpr->name.toString();
    if (!name.isEmpty()) {
        if (m_currentScope->scopeType() == QQmlJSScope::QMLScope) {
            QQmlJSMetaMethod method(name, QStringLiteral("void"));
            method.setMethodType(QQmlJSMetaMethod::Method);
            FormalParameterList *parameters = fexpr->formals;
            while (parameters) {
                method.addParameter(parameters->element->bindingIdentifier.toString(), QString());
                parameters = parameters->next;
            }
            m_currentScope->addOwnMethod(method);
        } else {
            m_currentScope->insertJSIdentifier(
                        name, {
                            QQmlJSScope::JavaScriptIdentifier::LexicalScoped,
                            fexpr->firstSourceLocation()
                        });
        }
        enterEnvironment(QQmlJSScope::JSFunctionScope, name, fexpr->firstSourceLocation());
    } else {
        enterEnvironment(QQmlJSScope::JSFunctionScope, QStringLiteral("<anon>"),
                         fexpr->firstSourceLocation());
    }
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::FunctionExpression *fexpr)
{
    visitFunctionExpressionHelper(fexpr);
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::FunctionExpression *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::FunctionDeclaration *fdecl)
{
    visitFunctionExpressionHelper(fdecl);
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::FunctionDeclaration *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::ClassExpression *ast)
{
    QQmlJSMetaProperty prop;
    prop.setPropertyName(ast->name.toString());
    m_currentScope->addOwnProperty(prop);
    enterEnvironment(QQmlJSScope::JSFunctionScope, ast->name.toString(),
                     ast->firstSourceLocation());
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::ClassExpression *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(UiScriptBinding *scriptBinding)
{
    const auto id = scriptBinding->qualifiedId;
    const auto *statement = cast<ExpressionStatement *>(scriptBinding->statement);
    if (!id->next && id->name == QLatin1String("id")) {
        const auto *idExprension = cast<IdentifierExpression *>(statement->expression);
        m_scopesById.insert(idExprension->name.toString(), m_currentScope);
    } else {
        for (auto group = id; group->next; group = group->next) {
            const QString name = group->name.toString();

            if (name.isEmpty() || name.front().isUpper())
                break; // TODO: uppercase grouped scopes are attached properties. Handle them.

            enterEnvironment(QQmlJSScope::GroupedPropertyScope, name, group->firstSourceLocation());
        }

        // TODO: remember the actual binding, once we can process it.

        while (m_currentScope->scopeType() == QQmlJSScope::GroupedPropertyScope)
            leaveEnvironment();

        if (!statement || !statement->expression->asFunctionDefinition()) {
            enterEnvironment(QQmlJSScope::JSFunctionScope, QStringLiteral("binding"),
                             scriptBinding->statement->firstSourceLocation());
        }
    }

    return true;
}

void QQmlJSImportVisitor::endVisit(UiScriptBinding *scriptBinding)
{
    const auto id = scriptBinding->qualifiedId;
    if (id->next || id->name != QLatin1String("id")) {
        const auto *statement = cast<ExpressionStatement *>(scriptBinding->statement);
        if (!statement || !statement->expression->asFunctionDefinition())
            leaveEnvironment();
    }
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::UiEnumDeclaration *uied)
{
    QQmlJSMetaEnum qmlEnum(uied->name.toString());
    for (const auto *member = uied->members; member; member = member->next)
        qmlEnum.addKey(member->member.toString());
    m_currentScope->addEnum(qmlEnum);
    return true;
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::UiImport *import)
{
    // construct path
    QString prefix = QLatin1String("");
    if (import->asToken.isValid()) {
        prefix += import->importId;
    }
    auto filename = import->fileName.toString();
    if (!filename.isEmpty()) {
        const QFileInfo file(filename);
        const QFileInfo path(file.isRelative() ? QDir(m_implicitImportDirectory).filePath(filename)
                                               : filename);
        if (path.isDir()) {
            m_rootScopeImports.insert(m_importer->importDirectory(path.canonicalFilePath(), prefix));
        } else if (path.isFile()) {
            const auto scope = m_importer->importFile(path.canonicalFilePath());
            m_rootScopeImports.insert(prefix.isEmpty() ? scope->internalName() : prefix, scope);
        }

    }

    QString path {};
    if (!import->importId.isEmpty()) {
        // TODO: do not put imported ids into the same space as qml IDs
        const QString importId = import->importId.toString();
        m_scopesById.insert(importId, m_rootScopeImports.value(importId));
    }
    auto uri = import->importUri;
    while (uri) {
        path.append(uri->name);
        path.append(u'/');
        uri = uri->next;
    }
    path.chop(1);

    const auto imported = m_importer->importModule(
                path, prefix, import->version ? import->version->version : QTypeRevision());

    m_rootScopeImports.insert(imported);

    m_errors.append(m_importer->takeWarnings());
    return true;
}

void QQmlJSImportVisitor::throwRecursionDepthError()
{
    m_errors.append({
                        QStringLiteral("Maximum statement or expression depth exceeded"),
                        QtCriticalMsg,
                        QQmlJS::SourceLocation()
                    });
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::ClassDeclaration *ast)
{
    enterEnvironment(QQmlJSScope::JSFunctionScope, ast->name.toString(),
                     ast->firstSourceLocation());
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::ClassDeclaration *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::ForStatement *ast)
{
    enterEnvironment(QQmlJSScope::JSLexicalScope, QStringLiteral("forloop"),
                     ast->firstSourceLocation());
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::ForStatement *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::ForEachStatement *ast)
{
    enterEnvironment(QQmlJSScope::JSLexicalScope, QStringLiteral("foreachloop"),
                     ast->firstSourceLocation());
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::ForEachStatement *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::Block *ast)
{
    enterEnvironment(QQmlJSScope::JSLexicalScope, QStringLiteral("block"),
                     ast->firstSourceLocation());
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::Block *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::CaseBlock *ast)
{
    enterEnvironment(QQmlJSScope::JSLexicalScope, QStringLiteral("case"),
                     ast->firstSourceLocation());
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::CaseBlock *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::Catch *catchStatement)
{
    enterEnvironment(QQmlJSScope::JSLexicalScope, QStringLiteral("catch"),
                     catchStatement->firstSourceLocation());
    m_currentScope->insertJSIdentifier(
                catchStatement->patternElement->bindingIdentifier.toString(), {
                    QQmlJSScope::JavaScriptIdentifier::LexicalScoped,
                    catchStatement->patternElement->firstSourceLocation()
                });
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::Catch *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::WithStatement *ast)
{
    enterEnvironment(QQmlJSScope::JSLexicalScope, QStringLiteral("with"),
                     ast->firstSourceLocation());
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::WithStatement *)
{
    leaveEnvironment();
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::VariableDeclarationList *vdl)
{
    while (vdl) {
        m_currentScope->insertJSIdentifier(
                    vdl->declaration->bindingIdentifier.toString(),
                    {
                        (vdl->declaration->scope == QQmlJS::AST::VariableScope::Var)
                            ? QQmlJSScope::JavaScriptIdentifier::FunctionScoped
                            : QQmlJSScope::JavaScriptIdentifier::LexicalScoped,
                        vdl->declaration->firstSourceLocation()
                    });
        vdl = vdl->next;
    }
    return true;
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::FormalParameterList *fpl)
{
    for (auto const &boundName : fpl->boundNames()) {
        m_currentScope->insertJSIdentifier(
                    boundName.id, {
                        QQmlJSScope::JavaScriptIdentifier::Parameter,
                        fpl->firstSourceLocation()
                    });
    }
    return true;
}

bool QQmlJSImportVisitor::visit(QQmlJS::AST::UiObjectBinding *uiob)
{
    // property QtObject __styleData: QtObject {...}

    QString name;
    for (auto id = uiob->qualifiedTypeNameId; id; id = id->next)
        name += id->name.toString() + QLatin1Char('.');

    name.chop(1);

    QQmlJSMetaProperty prop;
    prop.setPropertyName(uiob->qualifiedId->name.toString());
    prop.setTypeName(name);
    prop.setIsWritable(true);
    prop.setIsPointer(true);
    prop.setIsAlias(name == QLatin1String("alias"));
    prop.setType(m_rootScopeImports.value(uiob->qualifiedTypeNameId->name.toString()));
    m_currentScope->addOwnProperty(prop);

    enterEnvironment(QQmlJSScope::QMLScope, name, uiob->firstSourceLocation());
    m_currentScope->resolveTypes(m_rootScopeImports);
    return true;
}

void QQmlJSImportVisitor::endVisit(QQmlJS::AST::UiObjectBinding *uiob)
{
    m_currentScope->resolveGroupedScopes();
    const QQmlJSScope::ConstPtr childScope = m_currentScope;
    leaveEnvironment();

    QQmlJSMetaProperty property = m_currentScope->property(uiob->qualifiedId->name.toString());
    property.setType(childScope);
    m_currentScope->addOwnProperty(property);
}

QT_END_NAMESPACE