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** This file is part of the Qt Build Suite.
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#include "itemreaderastvisitor.h"
#include "asttools.h"
#include "builtindeclarations.h"
#include "identifiersearch.h"
#include "itemreader.h"
#include <jsextensions/jsextensions.h>
#include <parser/qmljsast_p.h>
#include <tools/error.h>
#include <tools/fileinfo.h>
#include <tools/qbsassert.h>
#include <tools/qttools.h>
#include <logging/translator.h>

#include <QDirIterator>
#include <QFileInfo>
#include <QStringList>

using namespace QbsQmlJS;

namespace qbs {
namespace Internal {

ItemReaderASTVisitor::ItemReaderASTVisitor(ItemReader *reader, ItemReaderResult *result)
    : m_reader(reader)
    , m_readerResult(result)
    , m_languageVersion(readImportVersion(reader->builtins()->languageVersion()))
    , m_file(FileContext::create())
    , m_item(0)
    , m_sourceValue(0)
{
}

ItemReaderASTVisitor::~ItemReaderASTVisitor()
{
}

void ItemReaderASTVisitor::setFilePath(const QString &filePath)
{
    m_file->setFilePath(filePath);
}

void ItemReaderASTVisitor::setSourceCode(const QString &sourceCode)
{
    m_file->setContent(sourceCode);
}

bool ItemReaderASTVisitor::visit(AST::UiProgram *ast)
{
    Q_UNUSED(ast);
    m_sourceValue.clear();
    m_file->m_searchPaths = m_reader->searchPaths();

    if (Q_UNLIKELY(!ast->members->member))
        throw ErrorInfo(Tr::tr("No root item found in %1.").arg(m_file->filePath()));

    return true;
}

bool ItemReaderASTVisitor::addPrototype(const QString &fileName, const QString &filePath,
                                        const QString &as, bool needsCheck)
{
    if (needsCheck && fileName.size() <= 4)
        return false;

    const QString componentName = fileName.left(fileName.size() - 4);
    // ### validate componentName

    if (needsCheck && !componentName.at(0).isUpper())
        return false;

    QStringList prototypeName;
    if (!as.isEmpty())
        prototypeName.append(as);
    prototypeName.append(componentName);
    m_typeNameToFile.insert(prototypeName, filePath);
    return true;
}

void ItemReaderASTVisitor::collectPrototypes(const QString &path, const QString &as)
{
    QStringList fileNames; // Yes, file *names*.
    if (m_reader->findDirectoryEntries(path, &fileNames)) {
        foreach (const QString &fileName, fileNames)
            addPrototype(fileName, path + QLatin1Char('/') + fileName, as, false);
        return;
    }

    QDirIterator dirIter(path, QStringList(QLatin1String("*.qbs")));
    while (dirIter.hasNext()) {
        const QString filePath = dirIter.next();
        const QString fileName = dirIter.fileName();
        if (addPrototype(fileName, filePath, as, true))
            fileNames << fileName;
    }
    m_reader->cacheDirectoryEntries(path, fileNames);
}

bool ItemReaderASTVisitor::visit(AST::UiImportList *uiImportList)
{
    foreach (const QString &searchPath, m_reader->searchPaths())
        collectPrototypes(searchPath + QLatin1String("/imports"), QString());

    const QString path = FileInfo::path(m_file->filePath());

    // files in the same directory are available as prototypes
    collectPrototypes(path, QString());

    QSet<QString> importAsNames;
    QHash<QString, JsImport> jsImports;

    for (const AST::UiImportList *it = uiImportList; it; it = it->next) {
        const AST::UiImport *const import = it->import;

        QStringList importUri;
        bool isBase = false;
        if (import->importUri) {
            importUri = toStringList(import->importUri);
            isBase = (importUri.size() == 1 && importUri.first() == QLatin1String("qbs"))
                    || (importUri.size() == 2 && importUri.first() == QLatin1String("qbs")
                        && importUri.last() == QLatin1String("base"));
            if (isBase)
                checkImportVersion(import->versionToken);
            else if (import->versionToken.length)
                m_reader->logger().printWarning(ErrorInfo(Tr::tr("Superfluous version specification."),
                                                    toCodeLocation(import->versionToken)));
        }

        QString as;
        if (isBase) {
            if (Q_UNLIKELY(!import->importId.isNull())) {
                throw ErrorInfo(Tr::tr("Import of qbs.base must have no 'as <Name>'"),
                            toCodeLocation(import->importIdToken));
            }
        } else {
            if (importUri.count() == 2 && importUri.first() == QLatin1String("qbs")) {
                const QString extensionName = importUri.last();
                if (JsExtensions::hasExtension(extensionName)) {
                    if (Q_UNLIKELY(!import->importId.isNull())) {
                        throw ErrorInfo(Tr::tr("Import of built-in extension '%1' "
                                               "must not have 'as' specifier.").arg(extensionName));
                    }
                    if (Q_UNLIKELY(m_file->m_jsExtensions.contains(extensionName))) {
                        m_reader->logger().printWarning(Tr::tr("Built-in extension '%1' already "
                                                               "imported.").arg(extensionName));
                    } else {
                        m_file->m_jsExtensions << extensionName;
                    }
                    continue;
                }
            }

            if (import->importId.isNull()) {
                if (!import->fileName.isNull()) {
                    throw ErrorInfo(Tr::tr("File imports require 'as <Name>'"),
                                    toCodeLocation(import->importToken));
                }
                if (importUri.isEmpty()) {
                    throw ErrorInfo(Tr::tr("Invalid import URI."),
                                    toCodeLocation(import->importToken));
                }
                as = importUri.last();
            } else {
                as = import->importId.toString();
            }

            if (Q_UNLIKELY(importAsNames.contains(as))) {
                throw ErrorInfo(Tr::tr("Cannot import into the same name more than once."),
                            toCodeLocation(import->importIdToken));
            }
            if (Q_UNLIKELY(JsExtensions::hasExtension(as))) {
                throw ErrorInfo(Tr::tr("Cannot reuse the name of built-in extension '%1'.")
                                .arg(as));
            }
            importAsNames.insert(as);
        }

        if (!import->fileName.isNull()) {
            QString filePath = FileInfo::resolvePath(path, import->fileName.toString());

            QFileInfo fi(filePath);
            if (Q_UNLIKELY(!fi.exists()))
                throw ErrorInfo(Tr::tr("Cannot find imported file %0.").arg(filePath),
                            CodeLocation(m_file->filePath(), import->fileNameToken.startLine,
                                         import->fileNameToken.startColumn));
            filePath = fi.canonicalFilePath();
            if (fi.isDir()) {
                collectPrototypes(filePath, as);
            } else {
                if (filePath.endsWith(QLatin1String(".js"), Qt::CaseInsensitive)) {
                    JsImport &jsImport = jsImports[as];
                    jsImport.scopeName = as;
                    jsImport.filePaths.append(filePath);
                    jsImport.location = toCodeLocation(import->firstSourceLocation());
                } else if (filePath.endsWith(QLatin1String(".qbs"), Qt::CaseInsensitive)) {
                    m_typeNameToFile.insert(QStringList(as), filePath);
                } else {
                    throw ErrorInfo(Tr::tr("Can only import .qbs and .js files"),
                                CodeLocation(m_file->filePath(), import->fileNameToken.startLine,
                                             import->fileNameToken.startColumn));
                }
            }
        } else if (!importUri.isEmpty()) {
            const QString importPath = isBase
                    ? QLatin1String("qbs/base") : importUri.join(QDir::separator());
            bool found = m_typeNameToFile.contains(importUri);
            if (!found) {
                foreach (const QString &searchPath, m_reader->searchPaths()) {
                    const QFileInfo fi(FileInfo::resolvePath(
                                           FileInfo::resolvePath(searchPath,
                                                                 QLatin1String("imports")),
                                           importPath));
                    if (fi.isDir()) {
                        // ### versioning, qbsdir file, etc.
                        const QString &resultPath = fi.absoluteFilePath();
                        collectPrototypes(resultPath, as);

                        QDirIterator dirIter(resultPath, QStringList(QLatin1String("*.js")));
                        while (dirIter.hasNext()) {
                            dirIter.next();
                            JsImport &jsImport = jsImports[as];
                            if (jsImport.scopeName.isNull()) {
                                jsImport.scopeName = as;
                                jsImport.location = toCodeLocation(import->firstSourceLocation());
                            }
                            jsImport.filePaths.append(dirIter.filePath());
                        }
                        found = true;
                        break;
                    }
                }
            }
            if (Q_UNLIKELY(!found)) {
                throw ErrorInfo(Tr::tr("import %1 not found")
                                .arg(importUri.join(QLatin1String("."))),
                                toCodeLocation(import->fileNameToken));
            }
        }
    }

    for (QHash<QString, JsImport>::const_iterator it = jsImports.constBegin();
         it != jsImports.constEnd(); ++it)
    {
        m_file->m_jsImports += it.value();
    }

    return false;
}

bool ItemReaderASTVisitor::visit(AST::UiObjectDefinition *ast)
{
    const QString typeName = ast->qualifiedTypeNameId->name.toString();

    Item *item = Item::create(m_reader->m_pool);
    item->m_file = m_file;
    item->m_parent = m_item;
    item->m_typeName = typeName;
    item->m_location = ::qbs::Internal::toCodeLocation(m_file->filePath(),
                                                       ast->qualifiedTypeNameId->identifierToken);

    if (m_item) {
        // Add this item to the children of the parent item.
        m_item->m_children += item;
    } else {
        // This is the root item.
        m_item = item;
        m_readerResult->rootItem = item;
    }

    if (ast->initializer) {
        qSwap(m_item, item);
        ast->initializer->accept(this);
        qSwap(m_item, item);
    }

    m_reader->m_builtins->setupItemForBuiltinType(item);

    if (item->typeName() != QLatin1String("Properties")
            && item->typeName() != QLatin1String("SubProject")) {
        setupAlternatives(item);
    }

    // resolve inheritance
    const QStringList fullTypeName = toStringList(ast->qualifiedTypeNameId);
    const QString baseTypeFileName = m_typeNameToFile.value(fullTypeName);
    if (!baseTypeFileName.isEmpty()) {
        const ItemReaderResult baseFile = m_reader->internalReadFile(baseTypeFileName);

        inheritItem(item, baseFile.rootItem);
        if (baseFile.rootItem->m_file->m_idScope) {
            // Make ids from the derived file visible in the base file.
            // ### Do we want to turn off this feature? It's QMLish but kind of strange.
            ensureIdScope(item->m_file);
            baseFile.rootItem->m_file->m_idScope->setPrototype(item->m_file->m_idScope);
        }
    }

    return false;
}

void ItemReaderASTVisitor::checkDuplicateBinding(Item *item, const QStringList &bindingName,
                                  const AST::SourceLocation &sourceLocation)
{
    if (Q_UNLIKELY(item->properties().contains(bindingName.last()))) {
        QString msg = Tr::tr("Duplicate binding for '%1'");
        throw ErrorInfo(msg.arg(bindingName.join(QLatin1String("."))),
                    qbs::Internal::toCodeLocation(m_file->filePath(), sourceLocation));
    }
}

bool ItemReaderASTVisitor::visit(AST::UiPublicMember *ast)
{
    PropertyDeclaration p;
    if (Q_UNLIKELY(ast->name.isEmpty()))
        throw ErrorInfo(Tr::tr("public member without name"));
    if (Q_UNLIKELY(ast->memberType.isEmpty()))
        throw ErrorInfo(Tr::tr("public member without type"));
    if (Q_UNLIKELY(ast->type == AST::UiPublicMember::Signal))
        throw ErrorInfo(Tr::tr("public member with signal type not supported"));
    p.setName(ast->name.toString());
    p.setType(PropertyDeclaration::propertyTypeFromString(ast->memberType.toString()));
    if (p.type() == PropertyDeclaration::UnknownType)
        throw ErrorInfo(Tr::tr("Unknown type '%1' in property declaration.")
                        .arg(ast->memberType.toString()), toCodeLocation(ast->typeToken));
    if (ast->typeModifier.compare(QLatin1String("list")))
        p.setFlags(p.flags() | PropertyDeclaration::ListProperty);
    else if (Q_UNLIKELY(!ast->typeModifier.isEmpty()))
        throw ErrorInfo(Tr::tr("public member with type modifier '%1' not supported").arg(
                        ast->typeModifier.toString()));

    m_item->m_propertyDeclarations.insert(p.name(), p);

    JSSourceValuePtr value = JSSourceValue::create();
    value->setFile(m_file);
    if (ast->statement) {
        m_sourceValue.swap(value);
        visitStatement(ast->statement);
        m_sourceValue.swap(value);
        const QStringList bindingName(p.name());
        checkDuplicateBinding(m_item, bindingName, ast->colonToken);
    }

    m_item->m_properties.insert(p.name(), value);
    return false;
}

bool ItemReaderASTVisitor::visit(AST::UiScriptBinding *ast)
{
    QBS_CHECK(ast->qualifiedId);
    QBS_CHECK(!ast->qualifiedId->name.isEmpty());

    const QStringList bindingName = toStringList(ast->qualifiedId);

    if (bindingName.length() == 1 && bindingName.first() == QLatin1String("id")) {
        AST::ExpressionStatement *expStmt =
                AST::cast<AST::ExpressionStatement *>(ast->statement);
        if (Q_UNLIKELY(!expStmt))
            throw ErrorInfo(Tr::tr("id: must be followed by identifier"));
        AST::IdentifierExpression *idExp =
                AST::cast<AST::IdentifierExpression *>(expStmt->expression);
        if (Q_UNLIKELY(!idExp || idExp->name.isEmpty()))
            throw ErrorInfo(Tr::tr("id: must be followed by identifier"));
        m_item->m_id = idExp->name.toString();
        ensureIdScope(m_file);
        m_file->m_idScope->m_properties[m_item->m_id] = ItemValue::create(m_item);
        return false;
    }

    JSSourceValuePtr value = JSSourceValue::create();
    value->setFile(m_file);
    m_sourceValue.swap(value);
    visitStatement(ast->statement);
    m_sourceValue.swap(value);

    Item *targetItem = targetItemForBinding(m_item, bindingName, value);
    checkDuplicateBinding(targetItem, bindingName, ast->qualifiedId->identifierToken);
    targetItem->m_properties.insert(bindingName.last(), value);
    return false;
}

bool ItemReaderASTVisitor::visit(AST::FunctionDeclaration *ast)
{
    FunctionDeclaration f;
    if (Q_UNLIKELY(ast->name.isNull()))
        throw ErrorInfo(Tr::tr("function decl without name"));
    f.setName(ast->name.toString());

    // remove the name
    QString funcNoName = textOf(m_file->content(), ast);
    funcNoName.replace(QRegExp(QLatin1String("^(\\s*function\\s*)\\w*")), QLatin1String("(\\1"));
    funcNoName.append(QLatin1Char(')'));
    f.setSourceCode(funcNoName);

    f.setLocation(toCodeLocation(ast->firstSourceLocation()));
    m_item->m_functions += f;
    return false;
}

Version ItemReaderASTVisitor::readImportVersion(const QString &str, const CodeLocation &location)
{
    QStringList lst = str.split(QLatin1Char('.'));
    if (Q_UNLIKELY(lst.count() < 1 || lst.count() > 2))
        throw ErrorInfo(Tr::tr("Wrong number of components in import version."), location);
    Version v;
    int *parts[] = {&v.majorVersionRef(), &v.minorVersionRef(), 0};
    for (int i = 0; i < lst.count(); ++i) {
        bool ok;
        *parts[i] = lst.at(i).toInt(&ok);
        if (Q_UNLIKELY(!ok))
            throw ErrorInfo(Tr::tr("Cannot parse import version."), location);
    }
    return v;
}

bool ItemReaderASTVisitor::visitStatement(AST::Statement *statement)
{
    QBS_CHECK(statement);
    QBS_CHECK(m_sourceValue);

    if (AST::cast<AST::Block *>(statement))
        m_sourceValue->m_flags |= JSSourceValue::HasFunctionForm;

    m_sourceValue->setFile(m_file);
    m_sourceValue->setSourceCode(textRefOf(m_file->content(), statement));
    m_sourceValue->setLocation(statement->firstSourceLocation().startLine,
                               statement->firstSourceLocation().startColumn);

    bool usesBase, usesOuter;
    IdentifierSearch idsearch;
    idsearch.add(QLatin1String("base"), &usesBase);
    idsearch.add(QLatin1String("outer"), &usesOuter);
    idsearch.start(statement);
    if (usesBase)
        m_sourceValue->m_flags |= JSSourceValue::SourceUsesBase;
    if (usesOuter)
        m_sourceValue->m_flags |= JSSourceValue::SourceUsesOuter;
    return false;
}

CodeLocation ItemReaderASTVisitor::toCodeLocation(const AST::SourceLocation &location) const
{
    return CodeLocation(m_file->filePath(), location.startLine, location.startColumn);
}

Item *ItemReaderASTVisitor::targetItemForBinding(Item *item,
                                                   const QStringList &bindingName,
                                                   const JSSourceValueConstPtr &value)
{
    Item *targetItem = item;
    const int c = bindingName.count() - 1;
    for (int i = 0; i < c; ++i) {
        ValuePtr v = targetItem->m_properties.value(bindingName.at(i));
        if (!v) {
            Item *newItem = Item::create(m_reader->m_pool);
            v = ItemValue::create(newItem);
            targetItem->m_properties.insert(bindingName.at(i), v);
        }
        if (Q_UNLIKELY(v->type() != Value::ItemValueType)) {
            QString msg = Tr::tr("Binding to non-item property.");
            throw ErrorInfo(msg, value->location());
        }
        ItemValuePtr jsv = v.staticCast<ItemValue>();
        targetItem = jsv->item();
    }
    return targetItem;
}

void ItemReaderASTVisitor::checkImportVersion(const AST::SourceLocation &versionToken) const
{
    if (!versionToken.length)
        return;
    const QString importVersionString = m_file->content().mid(versionToken.offset, versionToken.length);
    const Version importVersion = readImportVersion(importVersionString,
                                                    toCodeLocation(versionToken));
    if (Q_UNLIKELY(importVersion != m_languageVersion))
        throw ErrorInfo(Tr::tr("Incompatible qbs language version %1. This is version %2.").arg(
                        importVersionString, m_reader->builtins()->languageVersion()),
                    toCodeLocation(versionToken));
}

void ItemReaderASTVisitor::inheritItem(Item *dst, const Item *src)
{
    if (!src->typeName().isEmpty())
        dst->setTypeName(src->typeName());

    int insertPos = 0;
    for (int i = 0; i < src->m_children.count(); ++i) {
        Item *child = src->m_children.at(i);
        dst->m_children.insert(insertPos++, child);
        child->m_parent = dst;
    }

    for (QMap<QString, ValuePtr>::const_iterator it = src->m_properties.constBegin();
         it != src->m_properties.constEnd(); ++it)
    {
        ValuePtr &v = dst->m_properties[it.key()];
        if (v) {
            if (v->type() == it.value()->type()) {
                if (v->type() == Value::JSSourceValueType) {
                    JSSourceValuePtr sv = v.staticCast<JSSourceValue>();
                    while (sv->baseValue())
                        sv = sv->baseValue();
                    const JSSourceValuePtr baseValue = it.value().staticCast<JSSourceValue>();
                    sv->setBaseValue(baseValue);
                    for (QList<JSSourceValue::Alternative>::iterator it
                            = sv->m_alternatives.begin(); it != sv->m_alternatives.end(); ++it) {
                        JSSourceValue::Alternative &alternative = *it;
                        alternative.value->setBaseValue(baseValue);
                    }
                } else if (v->type() == Value::ItemValueType) {
                    QBS_CHECK(v.staticCast<ItemValue>()->item());
                    QBS_CHECK(it.value().staticCast<const ItemValue>()->item());
                    inheritItem(v.staticCast<ItemValue>()->item(),
                                it.value().staticCast<const ItemValue>()->item());
                } else {
                    QBS_CHECK(!"unexpected value type");
                }
            }
        } else {
            v = it.value();
        }
    }

    for (Item::PropertyDeclarationMap::const_iterator it
            = src->m_propertyDeclarations.constBegin();
            it != src->m_propertyDeclarations.constEnd(); ++it) {
        dst->m_propertyDeclarations[it.key()] = it.value();
    }
}

void ItemReaderASTVisitor::ensureIdScope(const FileContextPtr &file)
{
    if (!file->m_idScope) {
        file->m_idScope = Item::create(m_reader->m_pool);
        file->m_idScope->m_typeName = QLatin1String("IdScope");
    }
}

void ItemReaderASTVisitor::setupAlternatives(Item *item)
{
    QList<Item *>::iterator it = item->m_children.begin();
    while (it != item->m_children.end()) {
        Item *child = *it;
        if (child->typeName() == QLatin1String("Properties")) {
            handlePropertiesBlock(item, child);
            it = item->m_children.erase(it);
        } else {
            ++it;
        }
    }
}

class PropertiesBlockConverter
{
public:
    PropertiesBlockConverter(const QString &condition, Item *propertiesBlockContainer,
                             const Item *propertiesBlock)
        : m_propertiesBlockContainer(propertiesBlockContainer)
        , m_propertiesBlock(propertiesBlock)
    {
        m_alternative.condition = condition;
    }

    void operator()()
    {
        apply(m_propertiesBlockContainer, m_propertiesBlock);
    }

private:
    JSSourceValue::Alternative m_alternative;
    Item *m_propertiesBlockContainer;
    const Item *m_propertiesBlock;

    void apply(Item *a, const Item *b)
    {
        for (QMap<QString, ValuePtr>::const_iterator it = b->properties().constBegin();
                it != b->properties().constEnd(); ++it) {
            if (b == m_propertiesBlock && it.key() == QLatin1String("condition"))
                continue;
            if (it.value()->type() == Value::ItemValueType) {
                apply(a->itemProperty(it.key(), true)->item(),
                      it.value().staticCast<ItemValue>()->item());
            } else if (it.value()->type() == Value::JSSourceValueType) {
                ValuePtr aval = a->property(it.key());
                if (Q_UNLIKELY(aval && aval->type() != Value::JSSourceValueType))
                    throw ErrorInfo(Tr::tr("Incompatible value type in unconditional value at %1.").arg(
                                    aval->location().toString()));
                apply(it.key(), a, aval.staticCast<JSSourceValue>(),
                      it.value().staticCast<JSSourceValue>());
            } else {
                QBS_CHECK(!"Unexpected value type in conditional value.");
            }
        }
    }

    void apply(const QString &propertyName, Item *item, JSSourceValuePtr value,
               const JSSourceValuePtr &conditionalValue)
    {
        QBS_ASSERT(!value || value->file() == conditionalValue->file(), return);
        if (!value) {
            value = JSSourceValue::create();
            value->setFile(conditionalValue->file());
            item->setProperty(propertyName, value);
            static const QString undefinedKeyword = QLatin1String("undefined");
            value->setSourceCode(QStringRef(&undefinedKeyword));
        }
        m_alternative.value = conditionalValue;
        value->addAlternative(m_alternative);
    }
};

void ItemReaderASTVisitor::handlePropertiesBlock(Item *item, const Item *block)
{
    ValuePtr value = block->property(QLatin1String("condition"));
    if (Q_UNLIKELY(!value))
        throw ErrorInfo(Tr::tr("Properties.condition must be provided."),
                    block->location());
    if (Q_UNLIKELY(value->type() != Value::JSSourceValueType))
        throw ErrorInfo(Tr::tr("Properties.condition must be a value binding."),
                    block->location());
    JSSourceValuePtr srcval = value.staticCast<JSSourceValue>();
    const QString condition = srcval->sourceCodeForEvaluation();
    PropertiesBlockConverter convertBlock(condition, item, block);
    convertBlock();
}

} // namespace Internal
} // namespace qbs
