/*
 *  Copyright (C) 1999-2000 Harri Porten (porten@kde.org)
 *  Copyright (C) 2003, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved.
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#ifndef JSArray_h
#define JSArray_h

#include "ArrayConventions.h"
#include "ButterflyInlines.h"
#include "JSObject.h"

namespace JSC {

    class JSArray;
    class LLIntOffsetsExtractor;

    class JSArray : public JSNonFinalObject {
        friend class LLIntOffsetsExtractor;
        friend class Walker;
        friend class JIT;

public:
    typedef JSNonFinalObject Base;

    protected:
    explicit JSArray(VM& vm, Structure* structure, Butterfly* butterfly)
        : JSNonFinalObject(vm, structure, butterfly)
        {
        }

    public:
    static JSArray* create(VM&, Structure*, unsigned initialLength = 0);

        // tryCreateUninitialized is used for fast construction of arrays whose size and
        // contents are known at time of creation. Clients of this interface must:
        //   - null-check the result (indicating out of memory, or otherwise unable to allocate vector).
        //   - call 'initializeIndex' for all properties in sequence, for 0 <= i < initialLength.
    static JSArray* tryCreateUninitialized(VM&, Structure*, unsigned initialLength);

        JS_EXPORT_PRIVATE static bool defineOwnProperty(JSObject*, ExecState*, PropertyName, PropertyDescriptor&, bool throwException);

        static bool getOwnPropertySlot(JSCell*, ExecState*, PropertyName, PropertySlot&);
        static bool getOwnPropertyDescriptor(JSObject*, ExecState*, PropertyName, PropertyDescriptor&);

        static JS_EXPORTDATA const ClassInfo s_info;
        
    unsigned length() const { return getArrayLength(); }
        // OK to use on new arrays, but not if it might be a RegExpMatchArray.
        bool setLength(ExecState*, unsigned, bool throwException = false);

        void sort(ExecState*);
        void sort(ExecState*, JSValue compareFunction, CallType, const CallData&);
        void sortNumeric(ExecState*, JSValue compareFunction, CallType, const CallData&);

        void push(ExecState*, JSValue);
        JSValue pop(ExecState*);

    enum ShiftCountMode {
        // This form of shift hints that we're doing queueing. With this assumption in hand,
        // we convert to ArrayStorage, which has queue optimizations.
        ShiftCountForShift,

        // This form of shift hints that we're just doing care and feeding on an array that
        // is probably typically used for ordinary accesses. With this assumption in hand,
        // we try to preserve whatever indexing type it has already.
        ShiftCountForSplice
    };

    bool shiftCountForShift(ExecState* exec, unsigned startIndex, unsigned count)
        {
        return shiftCountWithArrayStorage(startIndex, count, ensureArrayStorage(exec->vm()));
    }
    bool shiftCountForSplice(ExecState* exec, unsigned startIndex, unsigned count)
    {
        return shiftCountWithAnyIndexingType(exec, startIndex, count);
    }
    template<ShiftCountMode shiftCountMode>
    bool shiftCount(ExecState* exec, unsigned startIndex, unsigned count)
    {
        switch (shiftCountMode) {
        case ShiftCountForShift:
            return shiftCountForShift(exec, startIndex, count);
        case ShiftCountForSplice:
            return shiftCountForSplice(exec, startIndex, count);
        default:
            CRASH();
            return false;
        }
        }

    bool unshiftCountForShift(ExecState* exec, unsigned startIndex, unsigned count)
        {
        return unshiftCountWithArrayStorage(exec, startIndex, count, ensureArrayStorage(exec->vm()));
            }
    bool unshiftCountForSplice(ExecState* exec, unsigned startIndex, unsigned count)
    {
        return unshiftCountWithAnyIndexingType(exec, startIndex, count);
        }
    template<ShiftCountMode shiftCountMode>
    bool unshiftCount(ExecState* exec, unsigned startIndex, unsigned count)
        {
        switch (shiftCountMode) {
        case ShiftCountForShift:
            return unshiftCountForShift(exec, startIndex, count);
        case ShiftCountForSplice:
            return unshiftCountForSplice(exec, startIndex, count);
        default:
            CRASH();
            return false;
        }
        }

        void fillArgList(ExecState*, MarkedArgumentBuffer&);
        void copyToArguments(ExecState*, CallFrame*, uint32_t length);

    static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype, IndexingType indexingType)
        {
        return Structure::create(vm, globalObject, prototype, TypeInfo(ObjectType, StructureFlags), &s_info, indexingType);
        }
        
    protected:
    static const unsigned StructureFlags = OverridesGetOwnPropertySlot | OverridesGetPropertyNames | JSObject::StructureFlags;
        static void put(JSCell*, ExecState*, PropertyName, JSValue, PutPropertySlot&);

        static bool deleteProperty(JSCell*, ExecState*, PropertyName);
    JS_EXPORT_PRIVATE static void getOwnNonIndexPropertyNames(JSObject*, ExecState*, PropertyNameArray&, EnumerationMode);

    private:
        bool isLengthWritable()
        {
        ArrayStorage* storage = arrayStorageOrNull();
        if (!storage)
            return true;
        SparseArrayValueMap* map = storage->m_sparseMap.get();
            return !map || !map->lengthIsReadOnly();
        }

    bool shiftCountWithAnyIndexingType(ExecState*, unsigned startIndex, unsigned count);
    bool shiftCountWithArrayStorage(unsigned startIndex, unsigned count, ArrayStorage*);

    bool unshiftCountWithAnyIndexingType(ExecState*, unsigned startIndex, unsigned count);
    bool unshiftCountWithArrayStorage(ExecState*, unsigned startIndex, unsigned count, ArrayStorage*);
    bool unshiftCountSlowCase(VM&, bool, unsigned);

    template<IndexingType indexingType>
    void sortNumericVector(ExecState*, JSValue compareFunction, CallType, const CallData&);
        
    template<IndexingType indexingType, typename StorageType>
    void sortCompactedVector(ExecState*, ContiguousData<StorageType>, unsigned relevantLength);
        
    template<IndexingType indexingType>
    void sortVector(ExecState*, JSValue compareFunction, CallType, const CallData&);

    bool setLengthWithArrayStorage(ExecState*, unsigned newLength, bool throwException, ArrayStorage*);
        void setLengthWritable(ExecState*, bool writable);

    template<IndexingType indexingType>
    void compactForSorting(unsigned& numDefined, unsigned& newRelevantLength);
    };

inline Butterfly* createContiguousArrayButterfly(VM& vm, unsigned length, unsigned& vectorLength)
    {
    IndexingHeader header;
    vectorLength = std::max(length, BASE_VECTOR_LEN);
    header.setVectorLength(vectorLength);
    header.setPublicLength(length);
    Butterfly* result = Butterfly::create(
        vm, 0, 0, true, header, vectorLength * sizeof(EncodedJSValue));
    return result;
}

inline Butterfly* createArrayButterfly(VM& vm, unsigned initialLength)
{
    Butterfly* butterfly = Butterfly::create(
        vm, 0, 0, true, baseIndexingHeaderForArray(initialLength), ArrayStorage::sizeFor(BASE_VECTOR_LEN));
    ArrayStorage* storage = butterfly->arrayStorage();
    storage->m_indexBias = 0;
    storage->m_sparseMap.clear();
    storage->m_numValuesInVector = 0;
    return butterfly;
}

Butterfly* createArrayButterflyInDictionaryIndexingMode(VM&, unsigned initialLength);

inline JSArray* JSArray::create(VM& vm, Structure* structure, unsigned initialLength)
{
    Butterfly* butterfly;
    if (LIKELY(!hasArrayStorage(structure->indexingType()))) {
        ASSERT(
            hasUndecided(structure->indexingType())
            || hasInt32(structure->indexingType())
            || hasDouble(structure->indexingType())
            || hasContiguous(structure->indexingType()));
        unsigned vectorLength;
        butterfly = createContiguousArrayButterfly(vm, initialLength, vectorLength);
        ASSERT(initialLength < MIN_SPARSE_ARRAY_INDEX);
        if (hasDouble(structure->indexingType())) {
            for (unsigned i = 0; i < vectorLength; ++i)
                butterfly->contiguousDouble()[i] = QNaN;
        }
    } else {
        ASSERT(
            structure->indexingType() == ArrayWithSlowPutArrayStorage
            || structure->indexingType() == ArrayWithArrayStorage);
        butterfly = createArrayButterfly(vm, initialLength);
    }
    JSArray* array = new (NotNull, allocateCell<JSArray>(vm.heap)) JSArray(vm, structure, butterfly);
    array->finishCreation(vm);
        return array;
    }

inline JSArray* JSArray::tryCreateUninitialized(VM& vm, Structure* structure, unsigned initialLength)
    {
    unsigned vectorLength = std::max(BASE_VECTOR_LEN, initialLength);
    if (vectorLength > MAX_STORAGE_VECTOR_LENGTH)
        return 0;
        
    Butterfly* butterfly;
    if (LIKELY(!hasArrayStorage(structure->indexingType()))) {
        ASSERT(
            hasUndecided(structure->indexingType())
            || hasInt32(structure->indexingType())
            || hasDouble(structure->indexingType())
            || hasContiguous(structure->indexingType()));

        void* temp;
        if (!vm.heap.tryAllocateStorage(Butterfly::totalSize(0, 0, true, vectorLength * sizeof(EncodedJSValue)), &temp))
            return 0;
        butterfly = Butterfly::fromBase(temp, 0, 0);
        butterfly->setVectorLength(vectorLength);
        butterfly->setPublicLength(initialLength);
        if (hasDouble(structure->indexingType())) {
            for (unsigned i = initialLength; i < vectorLength; ++i)
                butterfly->contiguousDouble()[i] = QNaN;
        }
    } else {
        void* temp;
        if (!vm.heap.tryAllocateStorage(Butterfly::totalSize(0, 0, true, ArrayStorage::sizeFor(vectorLength)), &temp))
            return 0;
        butterfly = Butterfly::fromBase(temp, 0, 0);
        *butterfly->indexingHeader() = indexingHeaderForArray(initialLength, vectorLength);
        ArrayStorage* storage = butterfly->arrayStorage();
        storage->m_indexBias = 0;
        storage->m_sparseMap.clear();
        storage->m_numValuesInVector = initialLength;
    }
        
    JSArray* array = new (NotNull, allocateCell<JSArray>(vm.heap)) JSArray(vm, structure, butterfly);
    array->finishCreation(vm);
    return array;
    }

    JSArray* asArray(JSValue);

    inline JSArray* asArray(JSCell* cell)
    {
        ASSERT(cell->inherits(&JSArray::s_info));
        return jsCast<JSArray*>(cell);
    }

    inline JSArray* asArray(JSValue value)
    {
        return asArray(value.asCell());
    }

    inline bool isJSArray(JSCell* cell) { return cell->classInfo() == &JSArray::s_info; }
    inline bool isJSArray(JSValue v) { return v.isCell() && isJSArray(v.asCell()); }

    inline JSArray* constructArray(ExecState* exec, Structure* arrayStructure, const ArgList& values)
    {
    VM& vm = exec->vm();
        unsigned length = values.size();
    JSArray* array = JSArray::tryCreateUninitialized(vm, arrayStructure, length);

        // FIXME: we should probably throw an out of memory error here, but
        // when making this change we should check that all clients of this
        // function will correctly handle an exception being thrown from here.
    RELEASE_ASSERT(array);

        for (unsigned i = 0; i < length; ++i)
        array->initializeIndex(vm, i, values.at(i));
        return array;
    }
    
    inline JSArray* constructArray(ExecState* exec, Structure* arrayStructure, const JSValue* values, unsigned length)
    {
    VM& vm = exec->vm();
    JSArray* array = JSArray::tryCreateUninitialized(vm, arrayStructure, length);

        // FIXME: we should probably throw an out of memory error here, but
        // when making this change we should check that all clients of this
        // function will correctly handle an exception being thrown from here.
    RELEASE_ASSERT(array);

        for (unsigned i = 0; i < length; ++i)
        array->initializeIndex(vm, i, values[i]);
        return array;
    }

} // namespace JSC

#endif // JSArray_h
