/* vim: set ts=4 sw=4 tw=99 et:

 *

 * Copyright (C) 2012 David Anderson

 *

 * This file is part of SourcePawn.

 *

 * SourcePawn is free software: you can redistribute it and/or modify it under

 * the terms of the GNU General Public License as published by the Free

 * Software Foundation, either version 3 of the License, or (at your option)

 * any later version.

 * 

 * SourcePawn 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 General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License along with

 * SourcePawn. If not, see http://www.gnu.org/licenses/.

 */

#include <string.h>

#include "Array.h"

#include "FixedArray.h"

#include "Heap.h"

#include "Zone.h"

#include "Structures.h"

#include "Heap-inl.h"

using namespace ke;

ArrayMap *

ArrayMap::New(Zone *zone, Handle<ArrayType> type)

{

    Local<Map> obj(zone, zone->allocateMap(MapKind_Array, sizeof(ArrayMap), MapKind_MetaArray));

    if (!obj)

        return NULL;

    Local<ArrayMap> map(zone, ArrayMap::cast(obj));

    map->type_ = type;

    return map;

}

ArrayMap *

ArrayMap::Attach(Zone *zone, Handle<ArrayType> type)

{

    if (type->newMap())

        return ArrayMap::cast(type->newMap());

    Local<ArrayMap> map(zone, ArrayMap::New(zone, type));

    if (!map)

        return NULL;

    // Ensure the inner type has an ArrayMap if needed.

    if (type->contained()->isArray()) {

        Local<ArrayType> contained(zone, ArrayType::cast(type->contained()));

        if (!ArrayMap::Attach(zone, contained))

            return NULL;

    }

    type->setNewMap(map);

    return map;

}

Array *

Array::NewRaw(Zone *zone, Handle<ArrayMap> map, unsigned nelements, Heap::Tenure tenure)

{

    if (nelements > (INT_MAX / SizeForElement(map->type()))) {

        zone->reportError(Message_ArraySizeTooBig);

        return NULL;

    }

    size_t bytes = sizeof(Array);

    if (map->type()->hasInlineElements())

        bytes += SizeForElement(map->type()) * nelements;

    Local<Array> array(zone, Array::cast(zone->allocate(map, bytes, tenure)));

    if (!array)

        return NULL;

    array->length_ = 0;

    array->elements_ = NULL;

    if (map->type()->hasInlineElements()) {

        // This must be a fixed array containing no traceables.

        assert(nelements > 0);

        assert(map->type()->isFixedLength());

        assert(!map->type()->contained()->isTraceable());

        // Compute an interior |elements_| pointer, such that if elements_

        // is accessed like a FixedArray, we reach the appropriate vector.

        array->elements_ = Address((Array *)array + 1) - ByteArray::offsetToElements();

        array->length_ = nelements;

        memset(array->bytes(), 0, SizeForElement(map->type()) * nelements);

        return array;

    }

    // If there is nothing to allocate, we don't bother creating elements yet.

    if (!nelements)

        return array;

    if (!map->type()->contained()->isTraceable()) {

        size_t nbytes = SizeForElement(map->type()) * nelements;

        Local<ByteArray> elements(zone, ByteArray::New(zone, nbytes, tenure));

        if (!elements)

            return NULL;

        array->updateLengthAndElements(zone, nelements, elements);

        return array;

    }

    Local<FixedArray> elements(zone, FixedArray::New(zone, nelements, tenure));

    if (!elements)

        return NULL;

    array->updateLengthAndElements(zone, nelements, elements);

    // If this is an array of structs, we're required to allocate those structs now.

    if (map->type()->contained()->isStruct()) {

        Local<StructType> childType(zone, StructType::cast(map->type()->contained()));

        Local<StructMap> childMap(zone, childType->newMap());

        Local<Struct> child(zone);

        for (unsigned i = 0; i < nelements; i++) {

            child = Struct::New(zone, childMap, tenure);

            if (!child)

                return NULL;

            elements->set(zone, i, child);

        }

    }

    return array;

}

static Array *

ConstructSizedArray(Zone *zone, Handle<ArrayMap> map, int dims[MAX_ARRAY_DEPTH],

                    unsigned level, Heap::Tenure tenure)

{

    Local<Array> array(zone, Array::NewRaw(zone, map, dims[level], tenure));

    if (!array)

        return NULL;

    if (map->type()->contained()->isArray()) {

        Local<ArrayType> childType(zone, ArrayType::cast(map->type()->contained()));

        Local<ArrayMap> childMap(zone, childType->newMap());

        Local<Array> child(zone);

        for (unsigned i = 0; i < unsigned(dims[level]); i++) {

            child = ConstructSizedArray(zone, childMap, dims, level + 1, tenure);

            if (!child)

                return NULL;

            array->writeObject(zone, i, child);

        }

    }

    return array;

}

Array *

Array::NewSized(Zone *zone, Handle<ArrayMap> map, int dims[MAX_ARRAY_DEPTH], Heap::Tenure tenure)

{

    for (size_t i = 0; i < map->type()->levels(); i++) {

        if (dims[i] < 0) {

            zone->reportError(Message_InvalidDimensionSize, dims[i], i);

            return NULL;

        }

    }

    return ConstructSizedArray(zone, map, dims, 0, tenure);

}

static Array *

ConstructFixedArray(Zone *zone, Handle<ArrayMap> map, Heap::Tenure tenure)

{

    unsigned length = map->type()->fixedLength();

    Local<Array> array(zone, Array::NewRaw(zone, map, length, tenure));

    if (!array)

        return NULL;

    if (map->type()->contained()->isArray()) {

        Local<ArrayType> childType(zone, ArrayType::cast(map->type()->contained()));

        Local<ArrayMap> childMap(zone, childType->newMap());

        Local<Array> child(zone);

        if (childMap->type()->isFixedLength()) {

            for (unsigned i = 0; i < length; i++) {

                child = ConstructFixedArray(zone, childMap, tenure);

                if (!child)

                    return NULL;

                array->writeObject(zone, i, child);

            }

        } else {

            for (unsigned i = 0; i < length; i++) {

                child = Array::NewRaw(zone, childMap, 0, tenure);

                if (!child)

                    return NULL;

                array->writeObject(zone, i, child);

            }

        }

    }

    return array;

}

Array *

Array::NewFixed(Zone *zone, Handle<ArrayMap> map, Heap::Tenure tenure)

{

    return ConstructFixedArray(zone, map, tenure);

}

Array *

Array::NewString(Zone *zone, Handle<ArrayMap> map, Address buffer, size_t length, Heap::Tenure tenure)

{

    assert(map->type()->isCharArray());

    Local<Array> array(zone, Array::New1D(zone, map, length, tenure));

    if (!array)

        return NULL;

    assert(array->length() >= length);

    memcpy(array->chars(), buffer, length);

    return array;

}

Array *

Array::New1D(Zone *zone, Handle<ArrayMap> map, uint32 elements, Heap::Tenure tenure)

{

    assert(map->type()->levels());

    return Array::NewRaw(zone, map, elements, tenure);

}

Array *

Array::NewEmpty(Zone *zone, Handle<ArrayMap> map, Heap::Tenure tenure)

{

    assert(!map->type()->isFixedLength());

    return Array::NewRaw(zone, map, 0, tenure);

}

Array *

Array::NewExternal(Zone *zone, Handle<ArrayMap> map, void *buffer, unsigned length,

                   Heap::Tenure tenure)

{

    Local<Array> array(zone, Array::cast(zone->allocate(map, sizeof(Array), tenure)));

    if (!array)

        return NULL;

    array->length_ = length;

    array->elements_ = Address(buffer) - ByteArray::offsetToElements();

    return array;

}