#include "ZoneLoaderFactoryT4.h"

#include "ContentLoaderT4.h"
#include "Game/GameLanguage.h"
#include "Game/T4/GameT4.h"
#include "Game/T4/T4.h"
#include "Game/T4/ZoneConstantsT4.h"
#include "Loading/Processor/ProcessorInflate.h"
#include "Loading/Steps/StepAddProcessor.h"
#include "Loading/Steps/StepAllocXBlocks.h"
#include "Loading/Steps/StepLoadZoneContent.h"
#include "Loading/Steps/StepLoadZoneSizes.h"
#include "Loading/Steps/StepSkipBytes.h"
#include "Utils/ClassUtils.h"
#include "Utils/Endianness.h"

#include <cstring>

using namespace T4;

namespace
{
    void SetupBlock(ZoneMemory& zoneMemory)
    {
#define XBLOCK_DEF(name, type) std::make_unique<XBlock>(STR(name), name, type)

        zoneMemory.AddBlock(XBLOCK_DEF(T4::XFILE_BLOCK_TEMP, XBlockType::BLOCK_TYPE_TEMP));
        zoneMemory.AddBlock(XBLOCK_DEF(T4::XFILE_BLOCK_RUNTIME, XBlockType::BLOCK_TYPE_RUNTIME));
        zoneMemory.AddBlock(XBLOCK_DEF(T4::XFILE_BLOCK_LARGE_RUNTIME, XBlockType::BLOCK_TYPE_RUNTIME));
        zoneMemory.AddBlock(XBLOCK_DEF(T4::XFILE_BLOCK_PHYSICAL_RUNTIME, XBlockType::BLOCK_TYPE_RUNTIME));
        zoneMemory.AddBlock(XBLOCK_DEF(T4::XFILE_BLOCK_VIRTUAL, XBlockType::BLOCK_TYPE_NORMAL));
        zoneMemory.AddBlock(XBLOCK_DEF(T4::XFILE_BLOCK_LARGE, XBlockType::BLOCK_TYPE_NORMAL));
        zoneMemory.AddBlock(XBLOCK_DEF(T4::XFILE_BLOCK_PHYSICAL, XBlockType::BLOCK_TYPE_NORMAL));

#undef XBLOCK_DEF
    }
} // namespace

std::optional<ZoneLoaderInspectionResult> ZoneLoaderFactory::InspectZoneHeader(ZoneDataPeeking& filePeek) const
{
    const auto& header = filePeek.PeekStruct<ZoneHeader>();
    if (endianness::FromLittleEndian(header.m_version) == ZoneConstants::ZONE_VERSION_PC
        && !memcmp(header.m_magic, ZoneConstants::MAGIC_UNSIGNED, std::char_traits<char>::length(ZoneConstants::MAGIC_UNSIGNED)))
    {
        return ZoneLoaderInspectionResult{
            .m_game_id = GameId::T4,
            .m_variant_id = GameVariantId::T4_PC,
            // There is no way to know whether unsigned zones are official.
            .m_is_official = false,
            .m_is_signed = false,
            .m_is_encrypted = false,
        };
    }

    return std::nullopt;
}

std::unique_ptr<ZoneLoader> ZoneLoaderFactory::CreateLoaderForHeader(ZoneDataPeeking& filePeek,
                                                                     const std::string& fileName,
                                                                     std::optional<std::unique_ptr<ProgressCallback>> progressCallback) const
{
    const auto inspectResult = InspectZoneHeader(filePeek);
    if (!inspectResult)
        return nullptr;

    // Create new zone
    auto zone = std::make_unique<Zone>(fileName, 0, inspectResult->m_variant_id);
    auto* zonePtr = zone.get();
    zone->m_language = GameLanguage::LANGUAGE_NONE;

    // File is supported. Now setup all required steps for loading this file.
    auto zoneLoader = std::make_unique<ZoneLoader>(std::move(zone));

    SetupBlock(zonePtr->Memory());

    // Skip the initial header that we peeked at before
    zoneLoader->AddLoadingStep(step::CreateStepSkipBytes(sizeof(ZoneHeader)));

    zoneLoader->AddLoadingStep(step::CreateStepAddProcessor(processor::CreateProcessorInflate(ZoneConstants::AUTHED_CHUNK_SIZE)));
    zoneLoader->AddLoadingStep(step::CreateStepLoadZoneSizes());
    zoneLoader->AddLoadingStep(step::CreateStepAllocXBlocks(zonePtr));
    zoneLoader->AddLoadingStep(step::CreateStepLoadZoneContent(
        [zonePtr](ZoneInputStream& stream)
        {
            return std::make_unique<ContentLoader>(*zonePtr, stream);
        },
        32u,
        ZoneConstants::ZONE_POINTER_OFFSET_BIT_COUNT,
        ZoneConstants::ZONE_POINTER_BLOCK_BIT_COUNT,
        ZoneConstants::INSERT_BLOCK,
        zonePtr,
        std::move(progressCallback)));

    return zoneLoader;
}