/**
 * @file test_asset_cache.cpp
 * @brief AssetCache 单元测试
 * 
 * 测试资源缓存的添加、获取、淘汰等功能。
 */

#include "test_framework.h"
#include <extra2d/asset/asset_cache.h>
#include <extra2d/asset/asset.h>

using namespace extra2d;
using namespace extra2d::test;

// ---------------------------------------------------------------------------
// 测试辅助类
// ---------------------------------------------------------------------------

/**
 * @brief 测试用资源类
 */
class TestAsset : public Asset {
public:
    AssetType type() const override { return AssetType::Data; }
    
    bool loaded() const override {
        return state_.load(std::memory_order_acquire) == AssetState::Loaded;
    }
    
    size_t memSize() const override { return dataSize_; }
    
    void setData(size_t size) {
        dataSize_ = size;
        setState(AssetState::Loaded);
    }
    
    static Ref<TestAsset> create(const std::string& path, size_t size = 100) {
        auto asset = std::make_shared<TestAsset>();
        asset->setId(AssetID(path));
        asset->setPath(path);
        asset->setData(size);
        return asset;
    }

private:
    size_t dataSize_ = 0;
};

// ---------------------------------------------------------------------------
// 基本功能测试
// ---------------------------------------------------------------------------

TEST(AssetCache, Create) {
    AssetCache cache;
    
    TEST_ASSERT_EQ(0u, cache.count());
    TEST_ASSERT_EQ(0u, cache.bytes());
    TEST_ASSERT_EQ(0u, cache.limit());
}

TEST(AssetCache, CreateWithLimit) {
    AssetCache cache(1024 * 1024);
    
    TEST_ASSERT_EQ(1024 * 1024, cache.limit());
}

TEST(AssetCache, AddAsset) {
    AssetCache cache;
    
    auto asset = TestAsset::create("test.asset", 100);
    auto handle = cache.add(asset);
    
    TEST_ASSERT_TRUE(handle.valid());
    TEST_ASSERT_EQ(1u, cache.count());
    TEST_ASSERT_EQ(100u, cache.bytes());
}

TEST(AssetCache, AddNullAsset) {
    AssetCache cache;
    
    Ref<TestAsset> nullAsset;
    auto handle = cache.add(nullAsset);
    
    TEST_ASSERT_FALSE(handle.valid());
    TEST_ASSERT_EQ(0u, cache.count());
}

TEST(AssetCache, GetAsset) {
    AssetCache cache;
    
    auto asset = TestAsset::create("test.asset", 200);
    cache.add(asset);
    
    auto handle = cache.get<TestAsset>(AssetID("test.asset"));
    
    TEST_ASSERT_TRUE(handle.valid());
    TEST_ASSERT_TRUE(handle.get() != nullptr);
    TEST_ASSERT_EQ(asset.get(), handle.get().get());
}

TEST(AssetCache, GetNonExistent) {
    AssetCache cache;
    
    auto handle = cache.get<TestAsset>(AssetID("nonexistent.asset"));
    
    TEST_ASSERT_FALSE(handle.valid());
}

TEST(AssetCache, HasAsset) {
    AssetCache cache;
    
    auto asset = TestAsset::create("test.asset", 100);
    cache.add(asset);
    
    TEST_ASSERT_TRUE(cache.has(AssetID("test.asset")));
    TEST_ASSERT_FALSE(cache.has(AssetID("other.asset")));
}

TEST(AssetCache, RemoveAsset) {
    AssetCache cache;
    
    auto asset = TestAsset::create("test.asset", 100);
    cache.add(asset);
    
    TEST_ASSERT_TRUE(cache.remove(AssetID("test.asset")));
    TEST_ASSERT_EQ(0u, cache.count());
    TEST_ASSERT_FALSE(cache.has(AssetID("test.asset")));
}

TEST(AssetCache, RemoveNonExistent) {
    AssetCache cache;
    
    TEST_ASSERT_FALSE(cache.remove(AssetID("nonexistent.asset")));
}

// ---------------------------------------------------------------------------
// 缓存统计测试
// ---------------------------------------------------------------------------

TEST(AssetCache, Stats_Initial) {
    AssetCache cache;
    
    auto stats = cache.stats();
    
    TEST_ASSERT_EQ(0u, stats.hits);
    TEST_ASSERT_EQ(0u, stats.misses);
    TEST_ASSERT_EQ(0u, stats.count);
}

TEST(AssetCache, Stats_HitMiss) {
    AssetCache cache;
    
    auto asset = TestAsset::create("test.asset", 100);
    cache.add(asset);
    
    cache.get<TestAsset>(AssetID("test.asset"));
    cache.get<TestAsset>(AssetID("nonexistent.asset"));
    
    auto stats = cache.stats();
    
    TEST_ASSERT_EQ(1u, stats.hits);
    TEST_ASSERT_EQ(1u, stats.misses);
}

TEST(AssetCache, Stats_Reset) {
    AssetCache cache;
    
    auto asset = TestAsset::create("test.asset", 100);
    cache.add(asset);
    
    cache.get<TestAsset>(AssetID("test.asset"));
    cache.get<TestAsset>(AssetID("nonexistent.asset"));
    
    cache.resetStats();
    
    auto stats = cache.stats();
    
    TEST_ASSERT_EQ(0u, stats.hits);
    TEST_ASSERT_EQ(0u, stats.misses);
}

// ---------------------------------------------------------------------------
// 内存限制测试
// ---------------------------------------------------------------------------

TEST(AssetCache, SetLimit) {
    AssetCache cache;
    
    cache.setLimit(500);
    
    TEST_ASSERT_EQ(500u, cache.limit());
}

TEST(AssetCache, MemoryTracking) {
    AssetCache cache;
    
    auto asset1 = TestAsset::create("asset1", 100);
    auto asset2 = TestAsset::create("asset2", 200);
    
    cache.add(asset1);
    cache.add(asset2);
    
    TEST_ASSERT_EQ(300u, cache.bytes());
}

TEST(AssetCache, Clear) {
    AssetCache cache;
    
    auto asset1 = TestAsset::create("asset1", 100);
    auto asset2 = TestAsset::create("asset2", 200);
    
    cache.add(asset1);
    cache.add(asset2);
    
    cache.clear();
    
    TEST_ASSERT_EQ(0u, cache.count());
    TEST_ASSERT_EQ(0u, cache.bytes());
}

// ---------------------------------------------------------------------------
// LRU 测试
// ---------------------------------------------------------------------------

TEST(AssetCache, LRU_AccessOrder) {
    AssetCache cache;
    
    auto asset1 = TestAsset::create("asset1", 100);
    auto asset2 = TestAsset::create("asset2", 100);
    auto asset3 = TestAsset::create("asset3", 100);
    
    cache.add(asset1);
    cache.add(asset2);
    cache.add(asset3);
    
    cache.get<TestAsset>(AssetID("asset1"));
    
    TEST_ASSERT_TRUE(cache.has(AssetID("asset1")));
    TEST_ASSERT_TRUE(cache.has(AssetID("asset2")));
    TEST_ASSERT_TRUE(cache.has(AssetID("asset3")));
}

// ---------------------------------------------------------------------------
// Purge 测试
// ---------------------------------------------------------------------------

TEST(AssetCache, Purge_NoReferences) {
    AssetCache cache;
    
    {
        auto asset = TestAsset::create("test.asset", 100);
        cache.add(asset);
    }
    
    size_t purged = cache.purge();
    
    TEST_ASSERT_EQ(1u, purged);
    TEST_ASSERT_EQ(0u, cache.count());
}

TEST(AssetCache, Purge_WithReferences) {
    AssetCache cache;
    
    auto asset = TestAsset::create("test.asset", 100);
    auto handle = cache.add(asset);
    
    size_t purged = cache.purge();
    
    TEST_ASSERT_EQ(0u, purged);
    TEST_ASSERT_EQ(1u, cache.count());
}

// ---------------------------------------------------------------------------
// 多资源测试
// ---------------------------------------------------------------------------

TEST(AssetCache, MultipleAssets) {
    AssetCache cache;
    
    for (int i = 0; i < 10; ++i) {
        auto asset = TestAsset::create("asset" + std::to_string(i), 100);
        cache.add(asset);
    }
    
    TEST_ASSERT_EQ(10u, cache.count());
    TEST_ASSERT_EQ(1000u, cache.bytes());
    
    for (int i = 0; i < 10; ++i) {
        TEST_ASSERT_TRUE(cache.has(AssetID("asset" + std::to_string(i))));
    }
}

TEST(AssetCache, RemoveMultiple) {
    AssetCache cache;
    
    for (int i = 0; i < 5; ++i) {
        auto asset = TestAsset::create("asset" + std::to_string(i), 100);
        cache.add(asset);
    }
    
    for (int i = 0; i < 3; ++i) {
        cache.remove(AssetID("asset" + std::to_string(i)));
    }
    
    TEST_ASSERT_EQ(2u, cache.count());
    TEST_ASSERT_EQ(200u, cache.bytes());
}