#include "asset-manager.hpp"

TypeSafeInt_B(AssetHandle);

struct AssetBucket {
	Asset assets[256];
};

uint64_t assetBucketIncrementer = 2;
AssetHandle_T assetBucketCounter{0};
AssetHandle_T assetCounter{0};
AssetBucket *assetBuckets = nullptr;

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

AssetHandle RegisterAsset_Inner(const void *src, void *dst, int64_t size, const char *key) {

	AssetHandle_T assetHandle_T{Buckets_NewHandle<AssetBucket>(256ULL, assetBucketIncrementer, assetBucketCounter, assetCounter, assetBuckets)};
	AssetHandle assetHandle{assetHandle_T};

	if (src != nullptr) {
		std::memcpy(dst, src, size);
	}
	Asset *asset = &assetBuckets[Buckets_GetBucketIndex(assetHandle_T)].assets[Buckets_GetItemIndex(assetHandle_T)];
	asset->ptr = dst;
	asset->size = size;
	int64_t keyLen = std::strlen(key);
	std::memcpy(asset->key, key, keyLen > 16 ? 16 : keyLen);
	return assetHandle;
}

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");
	void *target = pke::PkeNew(size);
	return RegisterAsset_Inner(data, target, size, key);
}

AssetHandle RegisterAsset(const char *path) {
	std::ifstream file(path, std::ios::ate | std::ios::binary);
	if (!file.is_open()) {
		throw "failed to open file";
	}
	auto fileSize = (int64_t)file.tellg();
	void *target = pke::PkeNew(fileSize);

	int64_t pathLen = strlen(path);
	auto assetHandle = RegisterAsset_Inner(nullptr, target, 0, path + (pathLen > 16 ? pathLen - 16 : 0));
	AssetHandle_T assetHandle_T = static_cast<AssetHandle_T>(assetHandle);
	Asset *asset = &assetBuckets[Buckets_GetBucketIndex(assetHandle_T)].assets[Buckets_GetItemIndex(assetHandle_T)];
	file.seekg(0);
	file.read(static_cast<char *>(asset->ptr), fileSize);
	file.close();
	asset->size = fileSize;
	return assetHandle;
}

void DestroyAsset(AssetHandle assetHandle) {
	AssetHandle_T assetHandle_T = static_cast<AssetHandle_T>(assetHandle);
	auto itemIndex = Buckets_GetItemIndex(assetHandle_T);
	Asset *asset = &assetBuckets[Buckets_GetBucketIndex(assetHandle_T)].assets[itemIndex];
	pke::PkeDelete(asset->ptr, asset->size);
	for (long i = 0; i < 16; ++i) {
		asset->key[i] = 0;
	}
	asset->size = 0;
	asset->ptr = CAFE_BABE(void);
	if (itemIndex == assetCounter - (1ULL << 32)) {
		assetCounter -= (1ULL << 32);
	}
}

const Asset *GetAsset(AssetHandle assetHandle) {
	AssetHandle_T assetHandle_T = static_cast<AssetHandle_T>(assetHandle);
	return &assetBuckets[Buckets_GetBucketIndex(assetHandle_T)].assets[Buckets_GetItemIndex(assetHandle_T)];
}