// Copyright (C) 2021 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0

#include "qqmljsfunctioninitializer_p.h"

#include <private/qqmljsmemorypool_p.h>

#include <QtCore/qloggingcategory.h>
#include <QtCore/qfileinfo.h>

#include <QtQml/private/qqmlsignalnames_p.h>

QT_BEGIN_NAMESPACE

using namespace Qt::StringLiterals;

/*!
 * \internal
 * \class QQmlJSFunctionInitializer
 *
 * QQmlJSFunctionInitializer analyzes the IR to produce an initial
 * QQmlJSCompilePass::Function for further analysis. It only looks for the
 * signature and the QML scope and doesn't visit the byte code.
 */

static QString bindingTypeDescription(QmlIR::Binding::Type type)
{
    switch (type) {
    case QmlIR::Binding::Type_Invalid:
        return u"invalid"_s;
    case QmlIR::Binding::Type_Boolean:
        return u"a boolean"_s;
    case QmlIR::Binding::Type_Number:
        return u"a number"_s;
    case QmlIR::Binding::Type_String:
        return u"a string"_s;
    case QmlIR::Binding::Type_Null:
        return u"null"_s;
    case QmlIR::Binding::Type_Translation:
        return u"a translation"_s;
    case QmlIR::Binding::Type_TranslationById:
        return u"a translation by id"_s;
    case QmlIR::Binding::Type_Script:
        return u"a script"_s;
    case QmlIR::Binding::Type_Object:
        return u"an object"_s;
    case QmlIR::Binding::Type_AttachedProperty:
        return u"an attached property"_s;
    case QmlIR::Binding::Type_GroupProperty:
        return u"a grouped property"_s;
    }

    return u"nothing"_s;
}

void QQmlJSFunctionInitializer::populateSignature(
        const QV4::Compiler::Context *context, QQmlJS::AST::FunctionExpression *ast,
        QQmlJSCompilePass::Function *function, QQmlJS::DiagnosticMessage *error)
{
    const auto signatureError = [&](const QString &message) {
        error->type = QtWarningMsg;
        error->loc = ast->firstSourceLocation();
        error->message = message;
        function->isFullyTyped = false;
    };

    if (!m_typeResolver->canCallJSFunctions()) {
        signatureError(u"Ignoring type annotations as requested "
                       "by pragma FunctionSignatureBehavior"_s);
        return;
    }

    QQmlJS::AST::BoundNames arguments;
    if (ast->formals)
        arguments = ast->formals->formals();

    // If the function has no arguments and no return type annotation we assume it's untyped.
    // You can annotate it to return void to make it typed.
    // Otherwise we first assume it's typed and reset the flag if we detect a problem.
    function->isFullyTyped = !arguments.isEmpty() || ast->typeAnnotation;

    if (function->argumentTypes.isEmpty()) {
        for (const QQmlJS::AST::BoundName &argument : std::as_const(arguments)) {
            if (argument.typeAnnotation) {
                if (const auto type = m_typeResolver->typeFromAST(argument.typeAnnotation->type)) {
                    function->argumentTypes.append(
                                m_typeResolver->tracked(
                                    m_typeResolver->globalType(type)));
                } else {
                    function->argumentTypes.append(
                                m_typeResolver->tracked(
                                    m_typeResolver->globalType(m_typeResolver->varType())));
                    signatureError(u"Cannot resolve the argument type %1."_s
                                   .arg(argument.typeAnnotation->type->toString()));
                }
            } else {
                function->argumentTypes.append(
                            m_typeResolver->tracked(
                                m_typeResolver->globalType(m_typeResolver->varType())));
                signatureError(u"Functions without type annotations won't be compiled"_s);
            }
        }
    } else {
        for (qsizetype i = 0, end = arguments.size(); i != end; ++i) {
            const QQmlJS::AST::BoundName &argument = arguments[i];
            if (argument.typeAnnotation) {
                if (const auto type = m_typeResolver->typeFromAST(argument.typeAnnotation->type)) {
                    if (!m_typeResolver->registerContains(function->argumentTypes[i], type)) {
                        signatureError(u"Type annotation %1 on signal handler "
                                        "contradicts signal argument type %2"_s
                                       .arg(argument.typeAnnotation->type->toString(),
                                            function->argumentTypes[i].descriptiveName()));
                    }
                }
            }
        }
    }

    if (!function->returnType) {
        if (ast->typeAnnotation) {
            function->returnType = m_typeResolver->typeFromAST(ast->typeAnnotation->type);
            if (!function->returnType)
                signatureError(u"Cannot resolve return type %1"_s.arg(
                                   QmlIR::IRBuilder::asString(ast->typeAnnotation->type->typeId)));
        }
    }

    for (int i = QQmlJSCompilePass::FirstArgument + function->argumentTypes.size();
         i < context->registerCountInFunction; ++i) {
        function->registerTypes.append(m_typeResolver->tracked(
                                           m_typeResolver->globalType(m_typeResolver->voidType())));
    }

    function->addressableScopes = m_typeResolver->objectsById();
    function->code = context->code;
    function->sourceLocations = context->sourceLocationTable.get();
}

static void diagnose(
        const QString &message, QtMsgType type, const QQmlJS::SourceLocation &location,
        QQmlJS::DiagnosticMessage *error)
{
    *error = QQmlJS::DiagnosticMessage{
        message,
        type,
        location
    };
}

QQmlJSCompilePass::Function QQmlJSFunctionInitializer::run(
        const QV4::Compiler::Context *context,
        const QString &propertyName,
        QQmlJS::AST::Node *astNode,
        const QmlIR::Binding &irBinding,
        QQmlJS::DiagnosticMessage *error)
{
    QQmlJS::SourceLocation bindingLocation;
    bindingLocation.startLine = irBinding.location.line();
    bindingLocation.startColumn = irBinding.location.column();

    QQmlJSCompilePass::Function function;
    function.qmlScope = m_scopeType;

    if (irBinding.type() != QmlIR::Binding::Type_Script) {
        diagnose(u"Binding is not a script binding, but %1."_s.arg(
                     bindingTypeDescription(QmlIR::Binding::Type(quint32(irBinding.type())))),
                 QtDebugMsg, bindingLocation, error);
    }

    function.isProperty = m_objectType->hasProperty(propertyName);
    if (!function.isProperty) {
        if (QQmlSignalNames::isHandlerName(propertyName)) {
            if (auto actualPropertyName =
                QQmlSignalNames::changedHandlerNameToPropertyName(propertyName);
                actualPropertyName && m_objectType->hasProperty(*actualPropertyName)) {
                function.isSignalHandler = true;
            } else {
                auto signalName = QQmlSignalNames::handlerNameToSignalName(propertyName);
                const auto methods = m_objectType->methods(*signalName);
                for (const auto &method : methods) {
                    if (method.isCloned())
                        continue;
                    if (method.methodType() == QQmlJSMetaMethodType::Signal) {
                        function.isSignalHandler = true;
                        const auto arguments = method.parameters();
                        for (qsizetype i = 0, end = arguments.size(); i < end; ++i) {
                            const auto &type = arguments[i].type();
                            if (type.isNull()) {
                                diagnose(u"Cannot resolve the argument type %1."_s.arg(
                                                 arguments[i].typeName()),
                                         QtDebugMsg, bindingLocation, error);
                                function.argumentTypes.append(
                                        m_typeResolver->tracked(
                                                m_typeResolver->globalType(m_typeResolver->varType())));
                            } else {
                                function.argumentTypes.append(m_typeResolver->tracked(
                                        m_typeResolver->globalType(type)));
                            }
                        }
                        break;
                    }
                }
                if (!function.isSignalHandler) {
                    diagnose(u"Could not compile signal handler for %1: The signal does not exist"_s.arg(
                                     *signalName),
                             QtWarningMsg, bindingLocation, error);
                }
            }
        }
    }

    if (!function.isSignalHandler) {
        if (!function.isProperty) {
            diagnose(u"Could not compile binding for %1: The property does not exist"_s.arg(
                         propertyName),
                     QtWarningMsg, bindingLocation, error);
        }

        const auto property = m_objectType->property(propertyName);
        if (const QQmlJSScope::ConstPtr propertyType = property.type()) {
            function.returnType = propertyType->isListProperty()
                    ? m_typeResolver->qObjectListType()
                    : propertyType;
        } else {
            QString message = u"Cannot resolve property type %1 for binding on %2."_s
                    .arg(property.typeName(), propertyName);
            if (m_objectType->isNameDeferred(propertyName)) {
                // If the property doesn't exist but the name is deferred, then
                // it's deferred via the presence of immediate names. Those are
                // most commonly used to enable generalized grouped properties.
                message += u" You may want use ID-based grouped properties here.";
            }
            diagnose(message, QtWarningMsg, bindingLocation, error);
        }

        if (!property.bindable().isEmpty() && !property.isPrivate())
            function.isQPropertyBinding = true;
    }

    QQmlJS::MemoryPool pool;
    auto ast = astNode->asFunctionDefinition();
    if (!ast) {
        QQmlJS::AST::Statement *stmt = astNode->statementCast();
        if (!stmt) {
            Q_ASSERT(astNode->expressionCast());
            QQmlJS::AST::ExpressionNode *expr = astNode->expressionCast();
            stmt = new (&pool) QQmlJS::AST::ExpressionStatement(expr);
        }
        auto body = new (&pool) QQmlJS::AST::StatementList(stmt);
        body = body->finish();

        QString name = u"binding for "_s; // ####
        ast = new (&pool) QQmlJS::AST::FunctionDeclaration(
                pool.newString(name), /*formals*/ nullptr, body);
        ast->lbraceToken = astNode->firstSourceLocation();
        ast->functionToken = ast->lbraceToken;
        ast->rbraceToken = astNode->lastSourceLocation();
    }

    populateSignature(context, ast, &function, error);
    return function;
}

QQmlJSCompilePass::Function QQmlJSFunctionInitializer::run(
        const QV4::Compiler::Context *context,
        const QString &functionName, QQmlJS::AST::Node *astNode,
        QQmlJS::DiagnosticMessage *error)
{
    Q_UNUSED(functionName);

    QQmlJSCompilePass::Function function;
    function.qmlScope = m_scopeType;

    auto ast = astNode->asFunctionDefinition();
    Q_ASSERT(ast);

    populateSignature(context, ast, &function, error);
    return function;
}

QT_END_NAMESPACE
