#include "ZoneLoaderFactoryIW3.h"

#include <cassert>
#include <cstring>
#include <type_traits>

#include "Game/IW3/IW3.h"

#include "Utils/ClassUtils.h"
#include "ContentLoaderIW3.h"
#include "Game/IW3/GameAssetPoolIW3.h"
#include "Game/IW3/GameIW3.h"
#include "Game/GameLanguage.h"
#include "Game/IW3/ZoneConstantsIW3.h"
#include "Loading/Processor/ProcessorInflate.h"
#include "Loading/Steps/StepSkipBytes.h"
#include "Loading/Steps/StepAddProcessor.h"
#include "Loading/Steps/StepAllocXBlocks.h"
#include "Loading/Steps/StepLoadZoneContent.h"

using namespace IW3;

class ZoneLoaderFactory::Impl
{
    static GameLanguage GetZoneLanguage(std::string& zoneName)
    {
        return GameLanguage::LANGUAGE_NONE;
    }

    static bool CanLoad(ZoneHeader& header, bool* isSecure, bool* isOfficial)
    {
        assert(isSecure != nullptr);
        assert(isOfficial != nullptr);

        if (header.m_version != ZoneConstants::ZONE_VERSION)
        {
            return false;
        }

        if (!memcmp(header.m_magic, ZoneConstants::MAGIC_UNSIGNED, std::char_traits<char>::length(ZoneConstants::MAGIC_UNSIGNED)))
        {
            *isSecure = false;
            *isOfficial = true;
            return true;
        }

        return false;
    }

    static void SetupBlock(ZoneLoader* zoneLoader)
    {
#define XBLOCK_DEF(name, type) std::make_unique<XBlock>(STR(name), name, type)

        zoneLoader->AddXBlock(XBLOCK_DEF(IW3::XFILE_BLOCK_TEMP, XBlock::Type::BLOCK_TYPE_TEMP));
        zoneLoader->AddXBlock(XBLOCK_DEF(IW3::XFILE_BLOCK_RUNTIME, XBlock::Type::BLOCK_TYPE_RUNTIME));
        zoneLoader->AddXBlock(XBLOCK_DEF(IW3::XFILE_BLOCK_LARGE_RUNTIME, XBlock::Type::BLOCK_TYPE_RUNTIME));
        zoneLoader->AddXBlock(XBLOCK_DEF(IW3::XFILE_BLOCK_PHYSICAL_RUNTIME, XBlock::Type::BLOCK_TYPE_RUNTIME));
        zoneLoader->AddXBlock(XBLOCK_DEF(IW3::XFILE_BLOCK_VIRTUAL, XBlock::Type::BLOCK_TYPE_NORMAL));
        zoneLoader->AddXBlock(XBLOCK_DEF(IW3::XFILE_BLOCK_LARGE, XBlock::Type::BLOCK_TYPE_NORMAL));
        zoneLoader->AddXBlock(XBLOCK_DEF(IW3::XFILE_BLOCK_PHYSICAL, XBlock::Type::BLOCK_TYPE_NORMAL));
        zoneLoader->AddXBlock(XBLOCK_DEF(IW3::XFILE_BLOCK_VERTEX, XBlock::Type::BLOCK_TYPE_NORMAL));
        zoneLoader->AddXBlock(XBLOCK_DEF(IW3::XFILE_BLOCK_INDEX, XBlock::Type::BLOCK_TYPE_NORMAL));

#undef XBLOCK_DEF
    }

public:
    static ZoneLoader* CreateLoaderForHeader(ZoneHeader& header, std::string& fileName)
    {
        bool isSecure;
        bool isOfficial;

        // Check if this file is a supported IW4 zone.
        if (!CanLoad(header, &isSecure, &isOfficial))
            return nullptr;

        // Create new zone
        auto zone = std::make_unique<Zone>(fileName, 0, &g_GameIW3);
        auto* zonePtr = zone.get();
        zone->m_pools = std::make_unique<GameAssetPoolIW3>(zonePtr, 0);
        zone->m_language = GetZoneLanguage(fileName);

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

        SetupBlock(zoneLoader);

        // Skip unknown 1 byte field that the game ignores as well
        // zoneLoader->AddLoadingStep(std::make_unique<StepSkipBytes>(1));

        // Skip timestamp
        // zoneLoader->AddLoadingStep(std::make_unique<StepSkipBytes>(8));

        zoneLoader->AddLoadingStep(std::make_unique<StepAddProcessor>(std::make_unique<ProcessorInflate>(ZoneConstants::AUTHED_CHUNK_SIZE)));

        // Start of the XFile struct
        zoneLoader->AddLoadingStep(std::make_unique<StepSkipBytes>(8));
        // Skip size and externalSize fields since they are not interesting for us
        zoneLoader->AddLoadingStep(std::make_unique<StepAllocXBlocks>());

        // Start of the zone content
        zoneLoader->AddLoadingStep(std::make_unique<StepLoadZoneContent>(std::make_unique<ContentLoader>(), zonePtr, ZoneConstants::OFFSET_BLOCK_BIT_COUNT, ZoneConstants::INSERT_BLOCK));

        // Return the fully setup zoneloader
        return zoneLoader;
    }
};

ZoneLoader* ZoneLoaderFactory::CreateLoaderForHeader(ZoneHeader& header, std::string& fileName)
{
    return Impl::CreateLoaderForHeader(header, fileName);
}