package com.suisung.mall.common.utils;

import com.suisung.mall.core.web.service.RedisService;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;
import org.springframework.test.util.ReflectionTestUtils;

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;

import static org.junit.jupiter.api.Assertions.*;
import static org.mockito.Mockito.*;

/**
 * DistributedLockHelper综合测试套件
 */
public class DistributedLockHelperTest {

    private DistributedLockHelper lockHelper;

    @Mock
    private RedisService redisService;

    @BeforeEach
    public void setUp() {
        MockitoAnnotations.openMocks(this);
        lockHelper = new DistributedLockHelper();
        ReflectionTestUtils.setField(lockHelper, "redisService", redisService);
        System.out.println("=== 初始化测试环境 ===");
    }

    @Test
    public void testTryLock_Success() {
        System.out.println("开始执行: testTryLock_Success");

        // 给定条件
        String lockKey = "test_lock";
        long expireTimeSec = 30L;
        String expectedKey = "distributed_lock:" + lockKey;
        System.out.println("测试参数 - 锁键: " + lockKey + ", 过期时间: " + expireTimeSec + "秒");

        // 当调用时
        when(redisService.set(anyString(), anyString(), anyLong())).thenReturn(true);
        boolean result = lockHelper.tryLock(lockKey, expireTimeSec);
        System.out.println("获取锁结果: " + (result ? "成功" : "失败"));

        // 那么验证
        assertTrue(result, "锁应该成功获取");
        verify(redisService).set(eq(expectedKey), anyString(), eq(expireTimeSec));
        System.out.println("验证通过: Redis set 方法被正确调用");
        System.out.println("测试完成: testTryLock_Success\n");
    }

    @Test
    public void testTryLock_Failure() {
        System.out.println("开始执行: testTryLock_Failure");

        // 给定条件
        String lockKey = "test_lock";
        long expireTimeSec = 30L;
        System.out.println("测试参数 - 锁键: " + lockKey + ", 过期时间: " + expireTimeSec + "秒");

        // 当调用时
        when(redisService.set(anyString(), anyString(), anyLong())).thenThrow(new RuntimeException("Redis错误"));
        System.out.println("模拟Redis异常: Redis错误");

        // 那么验证
        assertThrows(RuntimeException.class, () -> {
            lockHelper.tryLock(lockKey, expireTimeSec);
        }, "应该抛出RuntimeException");
        System.out.println("验证通过: 正确捕获了RuntimeException");
        System.out.println("测试完成: testTryLock_Failure\n");
    }

    @Test
    public void testReleaseLock_Success() {
        System.out.println("开始执行: testReleaseLock_Success");

        // 给定条件
        String lockKey = "test_lock";
        String expectedKey = "distributed_lock:" + lockKey;
        String lockValue = "uuid:1";
        System.out.println("测试参数 - 锁键: " + lockKey + ", 锁值: " + lockValue);

        // 设置线程本地变量
        ReflectionTestUtils.setField(lockHelper, "LOCK_VALUE_HOLDER",
                new ThreadLocal<String>() {
                    @Override
                    protected String initialValue() {
                        return lockValue;
                    }
                });

        when(redisService.get(expectedKey)).thenReturn(lockValue);
        System.out.println("模拟Redis get返回值: " + lockValue);

        // 当调用时
        lockHelper.releaseLock(lockKey);
        System.out.println("执行锁释放操作");

        // 那么验证
        verify(redisService).del(expectedKey);
        System.out.println("验证通过: Redis del 方法被正确调用");
        System.out.println("测试完成: testReleaseLock_Success\n");
    }

    @Test
    public void testReleaseLock_WrongOwner() {
        System.out.println("开始执行: testReleaseLock_WrongOwner");

        // 给定条件
        String lockKey = "test_lock";
        String expectedKey = "distributed_lock:" + lockKey;
        String currentValue = "uuid:1";
        String threadValue = "uuid:2"; // 不同的值
        System.out.println("测试参数 - 当前锁值: " + currentValue + ", 线程锁值: " + threadValue);

        // 设置线程本地变量
        ReflectionTestUtils.setField(lockHelper, "LOCK_VALUE_HOLDER",
                new ThreadLocal<String>() {
                    @Override
                    protected String initialValue() {
                        return threadValue;
                    }
                });

        when(redisService.get(expectedKey)).thenReturn(currentValue);
        System.out.println("模拟Redis中当前锁值: " + currentValue);

        // 当调用时
        lockHelper.releaseLock(lockKey);
        System.out.println("执行锁释放操作");

        // 那么验证
        verify(redisService, never()).del(anyString());
        System.out.println("验证通过: Redis del 方法未被调用（防止误删）");
        System.out.println("测试完成: testReleaseLock_WrongOwner\n");
    }

    @Test
    public void testConcurrentAccess_SingleLockAcquirer() throws InterruptedException {
        System.out.println("开始执行: testConcurrentAccess_SingleLockAcquirer");

        // 给定条件
        String lockKey = "concurrent_test_lock";
        int threadCount = 10;
        ExecutorService executor = Executors.newFixedThreadPool(threadCount);
        CountDownLatch latch = new CountDownLatch(threadCount);
        AtomicInteger successCounter = new AtomicInteger(0);
        System.out.println("测试参数 - 并发线程数: " + threadCount + ", 锁键: " + lockKey);

        // 模拟Redis并发访问行为
        when(redisService.set(anyString(), anyString(), anyLong()))
                .thenAnswer(invocation -> {
                    // 只有第一次调用成功，其余都失败
                    boolean result = successCounter.get() == 0;
                    if (result) {
                        System.out.println("线程[" + Thread.currentThread().getName() + "] 成功获取锁");
                    }
                    return result;
                });
        System.out.println("模拟Redis行为: 只允许一个线程获取锁");

        // 当执行时
        for (int i = 0; i < threadCount; i++) {
            final int threadId = i;
            executor.submit(() -> {
                try {
                    System.out.println("启动线程[" + threadId + "]");
                    if (lockHelper.tryLock(lockKey, 30)) {
                        int count = successCounter.incrementAndGet();
                        System.out.println("线程[" + threadId + "] 获取锁成功，当前成功计数: " + count);
                        lockHelper.releaseLock(lockKey);
                        System.out.println("线程[" + threadId + "] 释放锁");
                    } else {
                        System.out.println("线程[" + threadId + "] 获取锁失败");
                    }
                } finally {
                    latch.countDown();
                    System.out.println("线程[" + threadId + "] 执行完毕，剩余线程数: " + (latch.getCount()));
                }
            });
        }

        boolean completed = latch.await(5, TimeUnit.SECONDS);
        executor.shutdown();
        System.out.println("所有线程执行完成: " + (completed ? "正常结束" : "超时结束"));

        // 那么验证
        int successCount = successCounter.get();
        assertEquals(1, successCount, "应该只有一个线程获得锁");
        System.out.println("验证通过: 实际成功获取锁的线程数为 " + successCount);
        System.out.println("测试完成: testConcurrentAccess_SingleLockAcquirer\n");
    }

    @Test
    public void testAutoRenewalFunctionality() throws InterruptedException {
        System.out.println("开始执行: testAutoRenewalFunctionality");

        // 给定条件
        String lockKey = "auto_renew_test_lock";
        long expireTimeSec = 5L;
        long maxHoldTimeSec = 10L;
        System.out.println("测试参数 - 锁键: " + lockKey + ", 过期时间: " + expireTimeSec + "秒, 最大持有时间: " + maxHoldTimeSec + "秒");

        when(redisService.set(anyString(), anyString(), anyLong())).thenReturn(true);
        when(redisService.get(anyString())).thenReturn("mock-value");
        System.out.println("模拟Redis set/get操作成功");

        // 当调用时
        DistributedLockHelper.LockHolder lockHolder =
                lockHelper.tryLockWithAutoRenew(lockKey, expireTimeSec, maxHoldTimeSec);
        System.out.println("获取带自动续期功能的锁");

        assertNotNull(lockHolder, "锁持有者不应为空");
        System.out.println("锁持有者创建成功");

        // 等待可能的续期操作
        System.out.println("等待3秒观察自动续期行为...");
        Thread.sleep(3000);

        // 那么验证
        verify(redisService, atLeastOnce()).expire(anyString(), anyLong());
        System.out.println("验证通过: Redis expire 方法至少被调用一次");

        // 清理
        lockHolder.close();
        System.out.println("关闭锁持有者，清理资源");
        System.out.println("测试完成: testAutoRenewalFunctionality\n");
    }

    @Test
    public void testLockHolderAutoClose() {
        System.out.println("开始执行: testLockHolderAutoClose");

        // 给定条件
        String lockKey = "auto_close_test_lock";
        System.out.println("测试参数 - 锁键: " + lockKey);

        when(redisService.set(anyString(), anyString(), anyLong())).thenReturn(true);
        when(redisService.get(anyString())).thenReturn("mock-value");
        System.out.println("模拟Redis操作成功");

        // 当调用时
        System.out.println("使用try-with-resources语法获取锁");
        try (DistributedLockHelper.LockHolder holder =
                     lockHelper.tryLockWithAutoRenew(lockKey, 30, 300)) {
            assertNotNull(holder, "锁持有者不应为空");
            System.out.println("锁持有者创建成功");
        }
        System.out.println("try-with-resources块结束，自动调用close方法");

        // 那么验证
        verify(redisService).del(anyString());
        System.out.println("验证通过: Redis del 方法被正确调用");
        System.out.println("测试完成: testLockHolderAutoClose\n");
    }

    @Test
    public void testMultipleLocksIndependence() {
        System.out.println("开始执行: testMultipleLocksIndependence");

        // 给定条件
        String lockKey1 = "lock_1";
        String lockKey2 = "lock_2";
        System.out.println("测试参数 - 锁键1: " + lockKey1 + ", 锁键2: " + lockKey2);

        when(redisService.set(anyString(), anyString(), anyLong())).thenReturn(true);
        System.out.println("模拟Redis set操作成功");

        // 当调用时
        boolean lock1Acquired = lockHelper.tryLock(lockKey1, 30);
        System.out.println("获取第一个锁: " + (lock1Acquired ? "成功" : "失败"));

        boolean lock2Acquired = lockHelper.tryLock(lockKey2, 30);
        System.out.println("获取第二个锁: " + (lock2Acquired ? "成功" : "失败"));

        // 那么验证
        assertTrue(lock1Acquired, "第一个锁应该成功获取");
        assertTrue(lock2Acquired, "第二个锁应该成功获取");
        System.out.println("两个锁都成功获取");

        // 验证它们是不同的键
        verify(redisService).set(eq("distributed_lock:" + lockKey1), anyString(), eq(30L));
        verify(redisService).set(eq("distributed_lock:" + lockKey2), anyString(), eq(30L));
        System.out.println("验证通过: 两个独立的锁键都被正确设置");
        System.out.println("测试完成: testMultipleLocksIndependence\n");
    }

    @Test
    public void testThreadIsolation() throws InterruptedException {
        System.out.println("开始执行: testThreadIsolation");

        // 给定条件
        String lockKey = "thread_isolation_lock";
        ExecutorService executor = Executors.newFixedThreadPool(2);
        CountDownLatch latch = new CountDownLatch(2);
        AtomicInteger[] results = new AtomicInteger[]{new AtomicInteger(0), new AtomicInteger(0)};
        System.out.println("测试参数 - 锁键: " + lockKey + ", 线程数: 2");

        when(redisService.set(anyString(), anyString(), anyLong())).thenReturn(true);
        System.out.println("模拟Redis set操作成功");

        // 当执行时
        System.out.println("启动两个线程竞争同一个锁");
        for (int i = 0; i < 2; i++) {
            final int threadIndex = i;
            executor.submit(() -> {
                try {
                    System.out.println("线程[" + threadIndex + "] 尝试获取锁");
                    if (lockHelper.tryLock(lockKey, 30)) {
                        int count = results[threadIndex].incrementAndGet();
                        System.out.println("线程[" + threadIndex + "] 获取锁成功，计数: " + count);
                        // 持有锁一段时间
                        Thread.sleep(100);
                        System.out.println("线程[" + threadIndex + "] 持有锁100ms后释放");
                        lockHelper.releaseLock(lockKey);
                        System.out.println("线程[" + threadIndex + "] 释放锁");
                    } else {
                        System.out.println("线程[" + threadIndex + "] 获取锁失败");
                    }
                } catch (InterruptedException e) {
                    System.out.println("线程[" + threadIndex + "] 被中断");
                    Thread.currentThread().interrupt();
                } finally {
                    latch.countDown();
                    System.out.println("线程[" + threadIndex + "] 执行完毕");
                }
            });
        }

        boolean completed = latch.await(5, TimeUnit.SECONDS);
        executor.shutdown();
        System.out.println("所有线程执行完成: " + (completed ? "正常结束" : "超时结束"));

        // 那么验证 - 两个线程都应该能够在不同时间获得锁
        int result0 = results[0].get();
        int result1 = results[1].get();
        assertEquals(1, result0, "线程0应该获得一次锁");
        assertEquals(1, result1, "线程1应该获得一次锁");
        System.out.println("验证通过: 线程0获得锁次数=" + result0 + ", 线程1获得锁次数=" + result1);
        System.out.println("测试完成: testThreadIsolation\n");
    }
}