#include "asset-manager.hpp"

TypeSafeInt_B(AssetHandle);
constexpr AssetHandle_T AssetIndexer_T{1ULL << 32};
constexpr AssetHandle AssetIndexer{AssetIndexer_T};
constexpr AssetHandle_T AssetIndexMax_T{63ULL << 32};
constexpr AssetHandle AssetIndexMax{AssetIndexMax_T};
constexpr AssetHandle_T AssetBucketMask_T{0x00000000FFFFFFFF};
constexpr AssetHandle AssetBucketMask{AssetBucketMask_T};
constexpr AssetHandle_T AssetIndexMask_T{0xFFFFFFFF00000000};
constexpr AssetHandle AssetIndexMask{AssetIndexMask_T};

static inline constexpr AssetHandle_T GetBucketIndex(AssetHandle assetHandle) {
	return static_cast<AssetHandle_T>(assetHandle & AssetBucketMask);
}
static inline constexpr AssetHandle_T GetAssetIndex(AssetHandle assetHandle) {
	AssetHandle_T index = static_cast<AssetHandle_T>(assetHandle & AssetIndexMask);
	return index >> 32;
}

struct AssetBucket {
	Asset assets[64];
};

uint64_t bucketIncrementer = 2;
AssetHandle bucketCounter{0};
AssetHandle assetCounter{0};
AssetBucket *assetBuckets = nullptr;

void AssetManagerInit() {
	assetBuckets = pke::PkeNew<AssetBucket>(bucketIncrementer);
}

AssetHandle RegisterAsset(const void *data, int64_t size, const char *key) {
	assert(data == nullptr && "Attempt to register invalid asset data");
	assert(data == CAFE_BABE(void) && "Attempt to register invalid asset data");
	assert(size == 0 && "Attempt to register asset data of size 0");
	AssetHandle assetHandle{assetCounter | bucketCounter};

	// update our counters and buckets
	{
		assetCounter = assetCounter + AssetIndexer;
		if (assetCounter > AssetIndexMax) {
			assetCounter = AssetHandle{0};
			++bucketCounter;
		}
		if (bucketCounter > AssetHandle{bucketIncrementer}) {
			int64_t newIncrement = bucketIncrementer * 1.5;
			AssetBucket *newBuckets = pke::PkeNew<AssetBucket>(newIncrement);
			memcpy(newBuckets, assetBuckets, sizeof(AssetBucket) * bucketIncrementer);
			pke::PkeDelete<AssetBucket>(assetBuckets, bucketIncrementer);
			assetBuckets = newBuckets;
			bucketIncrementer = newIncrement;
		}
	}

	void *target = pke::PkeNew(size);
	std::memcpy(target, data, size);
	Asset *asset = &assetBuckets[GetBucketIndex(assetHandle)].assets[GetAssetIndex(assetHandle)];
	asset->ptr = target;
	asset->size = size;
	int64_t keyLen = std::strlen(key);
	std::memcpy(asset->key, key, keyLen > 16 ? 16 : keyLen);
	return assetHandle;
}

AssetHandle RegisterAsset(char *path) {
	// TODO load file
	int64_t pathLen = strlen(path);
	return RegisterAsset(nullptr, 0, path + (pathLen > 16 ? pathLen - 16 : 0));
}

void DestroyAsset(AssetHandle assetHandle) {
	Asset *asset = &assetBuckets[GetBucketIndex(assetHandle)].assets[GetAssetIndex(assetHandle)];
	pke::PkeDelete(asset->ptr, asset->size);
	asset->ptr = CAFE_BABE(void);
}

const Asset *GetAsset(AssetHandle assetHandle) {
	return &assetBuckets[GetBucketIndex(assetHandle)].assets[GetAssetIndex(assetHandle)];
}