/* 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 "Types.h"

#include "Zone.h"

#include "Strings.h"

#include "Structures.h"

#include "Heap-inl.h"

using namespace ke;

Type *

Type::NewVoid(Zone *zone)

{

    Local<Type> type(zone, Type::cast(zone->allocate(MapKind_Type, sizeof(Type), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    type->kind_ = VOID;

    type->contained_ = NULL;

    return type;

}

Type *

Type::NewUnchecked(Zone *zone)

{

    Local<Type> type(zone, Type::cast(zone->allocate(MapKind_Type, sizeof(Type), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    type->kind_ = UNCHECKED;

    type->contained_ = NULL;

    return type;

}

Type *

Type::NewPrimitive(Zone *zone, PrimitiveType prim)

{

    Local<Type> type(zone, Type::cast(zone->allocate(MapKind_Type, sizeof(Type), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    type->kind_ = PRIMITIVE;

    type->name_ = NULL;

    type->contained_ = NULL;

    type->primitive_ = prim;

    return type;

}

Type *

Type::NewArray(Zone *zone, Handle<Type> contained, int elements, bool isConst)

{

    Local<Type> type(zone, Type::cast(zone->allocate(MapKind_Type, sizeof(Type), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    type->kind_ = ARRAY;

    type->name_ = NULL;

    type->contained_ = contained;

    type->elements_ = elements;

    if (!contained->isArray())

        type->levels_ = 1;

    else

        type->levels_ = contained->levels() + 1;

    type->const_ = isConst;

    return type;

}

Type *

Type::NewExternalArray(Zone *zone, Handle<Type> contained)

{

    Local<Type> type(zone, Type::cast(zone->allocate(MapKind_Type, sizeof(Type), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    assert(contained->isPrimitive());

    type->kind_ = EXTERNAL_ARRAY;

    type->name_ = NULL;

    type->contained_ = contained;

    type->elements_ = DYNAMIC_ARRAY_SIZE;

    type->levels_ = 1;

    type->const_ = false;

    return type;

}

Type *

Type::NewReference(Zone *zone, Handle<Type> contained, bool isConst)

{

    Local<Type> type(zone, Type::cast(zone->allocate(MapKind_Type, sizeof(Type), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    type->kind_ = REFERENCE;

    type->name_ = NULL;

    type->contained_ = contained;

    type->const_ = isConst;

    return type;

}

Type *

Type::NewEnum(Zone *zone, Handle<String> name)

{

    Local<Type> type(zone, Type::cast(zone->allocate(MapKind_Type, sizeof(Type), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    type->kind_ = ENUM;

    type->name_ = name;

    type->contained_ = NULL;

    return type;

}

#if 0

Type *

Type::NewNative(Zone *zone, Handle<Type> returnType, Handle<FixedArray> parameters,

                Handle<FixedArray> defaults, bool variadic)

{

    Local<Type> type(zone, Type::cast(zone->allocate(MapKind_Type, sizeof(Type), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    type->kind_ = NATIVE;

    type->name_ = NULL;

    type->contained_ = NULL;

    type->fields_ = NULL;

    type->newMap_ = NULL;

    type->returnType_ = returnType;

    type->parameters_ = parameters;

    type->defaults_ = defaults;

    type->variadicNative_ = variadic;

    return type;

}

#endif

bool

Type::Compare(Type *left, Type *right)

{

    if (left == right)

        return true;

    if (left->kind() != right->kind())

        return false;

    switch (left->kind()) {

      case Type::PRIMITIVE:

        return left->primitive() == right->primitive();

      case Type::ARRAY:

      {

        if (left->levels() != right->levels())

          return false;

        if (left->elements_ != right->elements_)

            return false;

        return Compare(left->contained(), right->contained());

      }

      case Type::FUNCTION:

      {

        FunctionType *fleft = FunctionType::cast(left);

        FunctionType *fright = FunctionType::cast(right);

        if (!Compare(fleft->returnType(), fright->returnType()))

            return false;

        if (fleft->parameters()->length() != fright->parameters()->length())

            return false;

        if (fleft->isNative() != fright->isNative())

            return false;

        if (fleft->isNative() && (fleft->isNativeVariadic() != fright->isNativeVariadic()))

            return false;

        for (unsigned i = 0; i < fleft->parameters()->length(); i++) {

            Type *leftparam = fleft->parameterAt(i);

            Type *rightparam = fright->parameterAt(i);

            if (!Compare(leftparam, rightparam))

                return false;

        }

        return true;

      }

      case Type::ENUM:

        return false;

      case Type::VOID:

      	return true;

      default:

        assert(left->kind() == Type::REFERENCE);

        return Compare(left->contained(), right->contained());

    }

}

StructType *

StructType::New(Zone *zone, Handle<String> name, Handle<FixedArray> fields)

{

    Local<StructType> type(zone, StructType::cast(zone->allocate(MapKind_StructType, sizeof(StructType), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    type->kind_ = STRUCT;

    type->name_ = name;

    type->contained_ = NULL;

    type->newMap_ = NULL;

    type->fields_ = fields;

    // Fill in field offsets.

    StructureBufferBuilder builder;

    Local<Type> fieldType(zone);

    for (size_t i = 0; i < fields->length(); i++) {

        Descriptor *desc = Descriptor::cast(fields->at(i));

        fieldType = desc->type();

        unsigned offset;

        if (!builder.add(fieldType, &offset))

            return NULL;

        desc->setOffset(offset);

    }

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

    if (!map)

        return NULL;

    type->newMap_ = map;

    return type;

}

Descriptor *

StructType::lookupField(Handle<String> name, unsigned *index)

{

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

        Descriptor *desc = Descriptor::cast(fields_->at(i));

        if (desc->name() == name) {

            if (index)

                *index = i;

            return desc;

        }

    }

    return NULL;

}

FunctionType *

FunctionType::New(Zone *zone, TokenKind token)

{

    Local<FunctionType> type(zone, FunctionType::cast(zone->allocate(MapKind_FunctionType, sizeof(FunctionType), Heap::Tenure_Old)));

    if (!type)

        return NULL;

    type->kind_ = FUNCTION;

    type->name_ = NULL;

    type->contained_ = NULL;

    type->parameters_ = NULL;

    type->defaults_ = NULL;

    type->returnType_ = NULL;

    type->token_ = token;

    return type;

}

// :TODO: this leaks an interior pointer.

const char *

ke::GetTypeName(Type *type)

{

    if (type->isArray())

        return "array";

    if (type->isFunction())

        return "function";

    if (type->isVoid())

        return "void";

    if (type->isEnum() || type->isStruct())

        return type->name()->chars();

    if (type->isReference())

        type = type->contained();

    switch (type->primitive()) {

      case PrimitiveType_Bool:

        return "bool";

      case PrimitiveType_Char:

        return "String";

      case PrimitiveType_Int32:

        return "int";

      case PrimitiveType_Float:

        return "Float";

      default:

        return "<unknown>";

    }

}