// ================================================================================================
// Audio Backend - 共享内存测试
// ================================================================================================

#include <gtest/gtest.h>
#include <gmock/gmock.h>
#include "communication/shm/shared_memory.h"
#include "tests/common/test_fixtures.h"
#include <thread>
#include <chrono>
#include <vector>
#include <string>
#include <mutex>
#include <condition_variable>
#include <atomic>

using namespace audio_backend;
using namespace audio_backend::communication;
using namespace std::chrono_literals;

// 共享内存测试固定装置
class SharedMemoryTest : public test::CommunicationTest {
protected:
    void SetUp() override {
        test::CommunicationTest::SetUp();
        
        // 创建基本配置
        base_config_.segment_name = "audio_backend_test_shm";
        base_config_.segment_size = 1024 * 1024;  // 1MB
        base_config_.create_if_not_exists = true;
        base_config_.remove_on_destroy = true;
    }
    
    void TearDown() override {
        // 确保共享内存管理器被销毁
        shm_manager_.reset();
        
        test::CommunicationTest::TearDown();
    }
    
    // 创建共享内存管理器
    std::unique_ptr<SharedMemoryManager> create_shm_manager(bool creating = true) {
        ShmConfig config = base_config_;
        
        // 如果不是创建者，就不要移除共享内存
        if (!creating) {
            config.remove_on_destroy = false;
        }
        
        return std::make_unique<SharedMemoryManager>(config);
    }

protected:
    ShmConfig base_config_;
    std::unique_ptr<SharedMemoryManager> shm_manager_;
};

// 测试创建和初始化
TEST_F(SharedMemoryTest, CreateAndInitialize) {
    // 创建共享内存管理器
    shm_manager_ = create_shm_manager();
    
    // 验证创建状态
    EXPECT_FALSE(shm_manager_->is_initialized());
    
    // 验证配置
    const auto& config = shm_manager_->get_config();
    EXPECT_EQ(config.segment_name, base_config_.segment_name);
    EXPECT_EQ(config.segment_size, base_config_.segment_size);
    EXPECT_TRUE(config.create_if_not_exists);
    EXPECT_TRUE(config.remove_on_destroy);
    
    // 初始化
    EXPECT_EQ(shm_manager_->initialize(), ShmError::Success);
    EXPECT_TRUE(shm_manager_->is_initialized());
    
    // 获取统计信息
    const auto& stats = shm_manager_->get_statistics();
    EXPECT_EQ(stats.total_size, base_config_.segment_size);
    EXPECT_GT(stats.used_size, 0);  // 至少有一些元数据
    EXPECT_LT(stats.used_size, stats.total_size);  // 但不会全部用完
    EXPECT_EQ(stats.allocation_count, 0);  // 还没有分配任何对象
}

// 测试对象分配和释放
TEST_F(SharedMemoryTest, AllocateAndDeallocate) {
    // 创建和初始化共享内存管理器
    shm_manager_ = create_shm_manager();
    ASSERT_EQ(shm_manager_->initialize(), ShmError::Success);
    
    // 分配简单对象
    int* test_int = shm_manager_->allocate_object<int>("test_int");
    ASSERT_NE(test_int, nullptr);
    
    // 设置值
    *test_int = 42;
    
    // 查找对象
    int* found_int = shm_manager_->find_object<int>("test_int");
    ASSERT_NE(found_int, nullptr);
    EXPECT_EQ(*found_int, 42);
    
    // 验证统计信息
    const auto& stats_after_alloc = shm_manager_->get_statistics();
    EXPECT_EQ(stats_after_alloc.allocation_count, 1);
    EXPECT_GT(stats_after_alloc.used_size, sizeof(int));  // 包括元数据和对象
    
    // 修改值并验证共享状态
    *test_int = 100;
    EXPECT_EQ(*found_int, 100);
    
    // 释放对象
    bool deallocated = shm_manager_->deallocate_object<int>("test_int");
    EXPECT_TRUE(deallocated);
    
    // 释放后应找不到对象
    int* not_found = shm_manager_->find_object<int>("test_int");
    EXPECT_EQ(not_found, nullptr);
    
    // 验证统计信息
    const auto& stats_after_dealloc = shm_manager_->get_statistics();
    EXPECT_EQ(stats_after_dealloc.allocation_count, 0);
    EXPECT_EQ(stats_after_dealloc.used_size, stats_after_dealloc.used_size);  // 应该回到初始状态
}

// 测试多个共享内存管理器访问相同的共享内存段
TEST_F(SharedMemoryTest, MultipleManagers) {
    // 创建第一个管理器（创建共享内存段）
    auto manager1 = create_shm_manager(true);  // 创建者
    ASSERT_EQ(manager1->initialize(), ShmError::Success);
    
    // 分配一些对象
    int* int_obj = manager1->allocate_object<int>("shared_int");
    ASSERT_NE(int_obj, nullptr);
    *int_obj = 42;
    
    float* float_obj = manager1->allocate_object<float>("shared_float");
    ASSERT_NE(float_obj, nullptr);
    *float_obj = 3.14159f;
    
    // 创建第二个管理器（访问现有共享内存段）
    auto manager2 = create_shm_manager(false);  // 非创建者
    ASSERT_EQ(manager2->initialize(), ShmError::Success);
    
    // 查找和验证对象
    int* found_int = manager2->find_object<int>("shared_int");
    ASSERT_NE(found_int, nullptr);
    EXPECT_EQ(*found_int, 42);
    
    float* found_float = manager2->find_object<float>("shared_float");
    ASSERT_NE(found_float, nullptr);
    EXPECT_FLOAT_EQ(*found_float, 3.14159f);
    
    // 通过第二个管理器修改值
    *found_int = 100;
    *found_float = 2.71828f;
    
    // 验证第一个管理器是否看到更改
    EXPECT_EQ(*int_obj, 100);
    EXPECT_FLOAT_EQ(*float_obj, 2.71828f);
}

// 测试复杂对象和结构体
TEST_F(SharedMemoryTest, ComplexStructures) {
    // 创建和初始化共享内存管理器
    shm_manager_ = create_shm_manager();
    ASSERT_EQ(shm_manager_->initialize(), ShmError::Success);
    
    // 定义复杂结构
    struct ComplexStruct {
        int id;
        float values[10];
        double ratio;
        char name[64];
    };
    
    // 分配结构
    ComplexStruct* complex_obj = shm_manager_->allocate_object<ComplexStruct>("complex_struct");
    ASSERT_NE(complex_obj, nullptr);
    
    // 初始化结构
    complex_obj->id = 123;
    for (int i = 0; i < 10; i++) {
        complex_obj->values[i] = i * 1.5f;
    }
    complex_obj->ratio = 16.0 / 9.0;
    strcpy(complex_obj->name, "音频后端测试结构");
    
    // 查找和验证
    ComplexStruct* found_struct = shm_manager_->find_object<ComplexStruct>("complex_struct");
    ASSERT_NE(found_struct, nullptr);
    EXPECT_EQ(found_struct->id, 123);
    for (int i = 0; i < 10; i++) {
        EXPECT_FLOAT_EQ(found_struct->values[i], i * 1.5f);
    }
    EXPECT_DOUBLE_EQ(found_struct->ratio, 16.0 / 9.0);
    EXPECT_STREQ(found_struct->name, "音频后端测试结构");
}

// 测试环形缓冲区
TEST_F(SharedMemoryTest, RingBufferTest) {
    // 创建和初始化共享内存管理器
    shm_manager_ = create_shm_manager();
    ASSERT_EQ(shm_manager_->initialize(), ShmError::Success);
    
    // 创建环形缓冲区
    const size_t buffer_capacity = 1024;
    RingBuffer<float> ring_buffer(*shm_manager_, "audio_samples", buffer_capacity);
    
    // 验证初始状态
    EXPECT_TRUE(ring_buffer.empty());
    EXPECT_FALSE(ring_buffer.full());
    EXPECT_EQ(ring_buffer.capacity(), buffer_capacity);
    EXPECT_EQ(ring_buffer.available(), 0);
    
    // 测试单个元素推入和弹出
    float test_sample = 0.5f;
    EXPECT_TRUE(ring_buffer.write(&test_sample, 1));
    EXPECT_FALSE(ring_buffer.empty());
    EXPECT_EQ(ring_buffer.available(), 1);
    
    float output_sample;
    EXPECT_TRUE(ring_buffer.read(&output_sample, 1));
    EXPECT_FLOAT_EQ(output_sample, test_sample);
    EXPECT_TRUE(ring_buffer.empty());
    
    // 测试批量操作
    std::vector<float> input_samples(100);
    for (size_t i = 0; i < input_samples.size(); ++i) {
        input_samples[i] = static_cast<float>(i) / 100.0f;
    }
    
    size_t pushed = ring_buffer.write(input_samples.data(), input_samples.size());
    EXPECT_EQ(pushed, input_samples.size());
    EXPECT_EQ(ring_buffer.available(), input_samples.size());
    
    std::vector<float> output_samples(input_samples.size());
    size_t popped = ring_buffer.read(output_samples.data(), output_samples.size());
    EXPECT_EQ(popped, input_samples.size());
    
    for (size_t i = 0; i < input_samples.size(); ++i) {
        EXPECT_FLOAT_EQ(output_samples[i], input_samples[i]);
    }
}

// 测试三缓冲机制
TEST_F(SharedMemoryTest, TripleBufferTest) {
    // 创建和初始化共享内存管理器
    shm_manager_ = create_shm_manager();
    ASSERT_EQ(shm_manager_->initialize(), ShmError::Success);
    
    // 创建三缓冲
    TripleBuffer<std::array<float, 512>> triple_buffer(*shm_manager_, "audio_frames");
    
    // 验证初始状态
    EXPECT_FALSE(triple_buffer.has_new_data());
    
    // 生产者写入数据
    auto* write_buffer = triple_buffer.get_write_buffer();
    ASSERT_NE(write_buffer, nullptr);
    
    // 填充测试数据
    for (size_t i = 0; i < write_buffer->size(); ++i) {
        (*write_buffer)[i] = static_cast<float>(i) / 512.0f;
    }
    
    // 提交写入
    triple_buffer.commit_write();
    EXPECT_TRUE(triple_buffer.has_new_data());
    
    // 消费者读取数据
    const auto* read_buffer = triple_buffer.get_read_buffer();
    ASSERT_NE(read_buffer, nullptr);
    
    // 验证数据
    for (size_t i = 0; i < read_buffer->size(); ++i) {
        EXPECT_FLOAT_EQ((*read_buffer)[i], static_cast<float>(i) / 512.0f);
    }
    
    // 提交读取
    triple_buffer.commit_read();
    EXPECT_FALSE(triple_buffer.has_new_data());
}

// 测试共享内存的并发安全性
TEST_F(SharedMemoryTest, ConcurrentAccess) {
    // 创建和初始化共享内存管理器
    shm_manager_ = create_shm_manager();
    ASSERT_EQ(shm_manager_->initialize(), ShmError::Success);
    
    // 创建环形缓冲区
    const size_t buffer_capacity = 1024;
    RingBuffer<int> ring_buffer(*shm_manager_, "concurrent_test", buffer_capacity);
    
    // 创建多个线程同时访问
    const int num_producers = 4;
    const int num_consumers = 4;
    const int items_per_producer = 1000;
    
    std::atomic<int> total_produced(0);
    std::atomic<int> total_consumed(0);
    
    // 创建生产者
    std::vector<std::thread> producers;
    for (int p = 0; p < num_producers; ++p) {
        producers.emplace_back([&, p]() {
            for (int i = 0; i < items_per_producer; ++i) {
                int value = p * items_per_producer + i;
                while (!ring_buffer.write(&value, 1)) {
                    // 缓冲区满，等待一下
                    std::this_thread::yield();
                }
                total_produced++;
            }
        });
    }
    
    // 创建消费者
    std::vector<std::thread> consumers;
    std::vector<std::set<int>> consumed_values(num_consumers);
    
    for (int c = 0; c < num_consumers; ++c) {
        consumers.emplace_back([&, c]() {
            while (total_consumed < num_producers * items_per_producer) {
                int value;
                if (ring_buffer.read(&value, 1)) {
                    consumed_values[c].insert(value);
                    total_consumed++;
                } else {
                    // 缓冲区空，等待一下
                    std::this_thread::yield();
                }
            }
        });
    }
    
    // 等待所有生产者完成
    for (auto& t : producers) {
        t.join();
    }
    
    // 等待所有消费者完成
    for (auto& t : consumers) {
        t.join();
    }
    
    // 验证所有的项都被消费了
    EXPECT_EQ(total_produced.load(), num_producers * items_per_producer);
    EXPECT_EQ(total_consumed.load(), num_producers * items_per_producer);
    
    // 合并所有消费者的集合
    std::set<int> all_consumed;
    for (const auto& set : consumed_values) {
        all_consumed.insert(set.begin(), set.end());
    }
    
    // 验证每个项只被消费了一次
    EXPECT_EQ(all_consumed.size(), num_producers * items_per_producer);
    
    // 验证所有项都被消费了
    for (int p = 0; p < num_producers; ++p) {
        for (int i = 0; i < items_per_producer; ++i) {
            int value = p * items_per_producer + i;
            EXPECT_TRUE(all_consumed.find(value) != all_consumed.end());
        }
    }
}

// 测试错误处理
TEST_F(SharedMemoryTest, ErrorHandling) {
    // 创建配置，但不创建共享内存
    ShmConfig config = base_config_;
    config.create_if_not_exists = false;  // 不创建新的
    
    // 尝试访问不存在的共享内存
    auto manager = std::make_unique<SharedMemoryManager>(config);
    EXPECT_NE(manager->initialize(), ShmError::Success);
    
    // 正确初始化
    shm_manager_ = create_shm_manager();
    ASSERT_EQ(shm_manager_->initialize(), ShmError::Success);
    
    // 尝试查找不存在的对象
    int* not_found = shm_manager_->find_object<int>("non_existent_object");
    EXPECT_EQ(not_found, nullptr);
    
    // 尝试释放不存在的对象
    bool deallocated = shm_manager_->deallocate_object<int>("non_existent_object");
    EXPECT_FALSE(deallocated);
    
    // 创建对象然后分配同名对象（应失败）
    int* obj1 = shm_manager_->allocate_object<int>("duplicate");
    ASSERT_NE(obj1, nullptr);
    *obj1 = 42;
    
    int* obj2 = shm_manager_->allocate_object<int>("duplicate");
    EXPECT_EQ(obj2, nullptr);
    
    // 检查第一个对象是否还完好
    int* check = shm_manager_->find_object<int>("duplicate");
    ASSERT_NE(check, nullptr);
    EXPECT_EQ(*check, 42);
}

// 测试性能和资源利用
TEST_F(SharedMemoryTest, PerformanceAndResource) {
    // 创建更大的共享内存段
    ShmConfig large_config = base_config_;
    large_config.segment_size = 10 * 1024 * 1024;  // 10MB
    
    auto large_manager = std::make_unique<SharedMemoryManager>(large_config);
    ASSERT_EQ(large_manager->initialize(), ShmError::Success);
    
    // 获取初始统计信息
    const auto& initial_stats = large_manager->get_statistics();
    
    // 分配大量小对象
    const int num_objects = 1000;
    std::vector<int*> objects;
    
    for (int i = 0; i < num_objects; ++i) {
        std::string name = "obj_" + std::to_string(i);
        int* obj = large_manager->allocate_object<int>(name);
        ASSERT_NE(obj, nullptr);
        *obj = i;
        objects.push_back(obj);
    }
    
    // 验证统计信息
    const auto& after_alloc_stats = large_manager->get_statistics();
    EXPECT_EQ(after_alloc_stats.allocation_count, num_objects);
    EXPECT_GT(after_alloc_stats.used_size, initial_stats.used_size);
    
    // 验证所有对象的值
    for (int i = 0; i < num_objects; ++i) {
        EXPECT_EQ(*objects[i], i);
    }
    
    // 释放一半对象
    for (int i = 0; i < num_objects / 2; ++i) {
        std::string name = "obj_" + std::to_string(i);
        bool deallocated = large_manager->deallocate_object<int>(name);
        EXPECT_TRUE(deallocated);
    }
    
    // 验证统计信息
    const auto& after_dealloc_stats = large_manager->get_statistics();
    EXPECT_EQ(after_dealloc_stats.allocation_count, num_objects / 2);
    EXPECT_LT(after_dealloc_stats.used_size, after_alloc_stats.used_size);
    
    // 确保我们可以再次分配这些对象
    for (int i = 0; i < num_objects / 2; ++i) {
        std::string name = "obj_" + std::to_string(i);
        int* obj = large_manager->allocate_object<int>(name);
        ASSERT_NE(obj, nullptr);
        *obj = i + 1000;  // 使用不同的值
    }
    
    // 验证所有对象的值
    for (int i = 0; i < num_objects / 2; ++i) {
        std::string name = "obj_" + std::to_string(i);
        int* obj = large_manager->find_object<int>(name);
        ASSERT_NE(obj, nullptr);
        EXPECT_EQ(*obj, i + 1000);
    }
    
    // 验证另一半对象的值
    for (int i = num_objects / 2; i < num_objects; ++i) {
        std::string name = "obj_" + std::to_string(i);
        int* obj = large_manager->find_object<int>(name);
        ASSERT_NE(obj, nullptr);
        EXPECT_EQ(*obj, i);
    }
}

int main(int argc, char** argv) {
    ::testing::InitGoogleTest(&argc, argv);
    return RUN_ALL_TESTS();
}