#include <gtest/gtest.h>
#include <string>
#include <vector>
#include <chrono>
#include "app.hpp"

// ============================================================================
// 测试夹具：CmsEngineTest
// ============================================================================
class CmsEngineTest : public ::testing::Test {
protected:
    CmsEngine engine;

    // 辅助函数：创建一个有效的事件（注意：EventRecord 没有 timestamp 成员）
    EventRecord createValidEvent(const std::string& id = "EVT-001", int priority = 100) {
        EventRecord evt;
        evt.id = id;
        evt.priority = priority;
        evt.status = EventStatus::Pending;
        return evt;
    }

    // 辅助函数：向引擎添加多个事件
    void addEventsToEngine(const std::vector<EventRecord>& events) {
        for (const auto& evt : events) {
            engine.ingestEvent(evt);
        }
    }
};

// ============================================================================
// ingestEvent 测试用例
// ============================================================================

/**
 * @brief 测试 ingestEvent 正常输入：有效事件应成功接入
 */
TEST_F(CmsEngineTest, testIngestEventValidEvent) {
    EventRecord evt = createValidEvent("EVT-001", 100);
    bool result = engine.ingestEvent(evt);
    EXPECT_TRUE(result);

    // 验证事件已存储
    const EventRecord* found = engine.findEventById("EVT-001");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->id, "EVT-001");
    EXPECT_EQ(found->priority, 100);
    EXPECT_EQ(found->status, EventStatus::Pending);
}

/**
 * @brief 测试 ingestEvent 边界值：优先级为 0 的最小值
 */
TEST_F(CmsEngineTest, testIngestEventPriorityMin) {
    EventRecord evt = createValidEvent("EVT-002", 0);
    bool result = engine.ingestEvent(evt);
    EXPECT_TRUE(result);

    const EventRecord* found = engine.findEventById("EVT-002");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->priority, 0);
}

/**
 * @brief 测试 ingestEvent 边界值：优先级为 255 的最大值
 */
TEST_F(CmsEngineTest, testIngestEventPriorityMax) {
    EventRecord evt = createValidEvent("EVT-003", 255);
    bool result = engine.ingestEvent(evt);
    EXPECT_TRUE(result);

    const EventRecord* found = engine.findEventById("EVT-003");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->priority, 255);
}

/**
 * @brief 测试 ingestEvent 异常输入：空 ID 应返回 false
 */
TEST_F(CmsEngineTest, testIngestEventEmptyId) {
    EventRecord evt = createValidEvent("", 100);
    bool result = engine.ingestEvent(evt);
    EXPECT_FALSE(result);

    // 验证事件未存储
    const EventRecord* found = engine.findEventById("");
    EXPECT_EQ(found, nullptr);
}

/**
 * @brief 测试 ingestEvent 异常输入：优先级超过 255 应返回 false
 */
TEST_F(CmsEngineTest, testIngestEventPriorityOverflow) {
    EventRecord evt = createValidEvent("EVT-004", 256);
    bool result = engine.ingestEvent(evt);
    EXPECT_FALSE(result);

    const EventRecord* found = engine.findEventById("EVT-004");
    EXPECT_EQ(found, nullptr);
}

/**
 * @brief 测试 ingestEvent 特殊场景：重复 ID 的事件应允许接入
 */
TEST_F(CmsEngineTest, testIngestEventDuplicateId) {
    EventRecord evt1 = createValidEvent("EVT-005", 100);
    EventRecord evt2 = createValidEvent("EVT-005", 200);

    bool result1 = engine.ingestEvent(evt1);
    EXPECT_TRUE(result1);

    bool result2 = engine.ingestEvent(evt2);
    EXPECT_TRUE(result2);

    // 验证两个事件都存储（findEventById 返回第一个匹配的）
    const EventRecord* found = engine.findEventById("EVT-005");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->priority, 100);
}

// ============================================================================
// processPendingEvents 测试用例
// ============================================================================

/**
 * @brief 测试 processPendingEvents 正常输入：处理所有 Pending 事件
 */
TEST_F(CmsEngineTest, testProcessPendingEventsAllPending) {
    std::vector<EventRecord> events = {
        createValidEvent("EVT-010", 100),
        createValidEvent("EVT-011", 200),
        createValidEvent("EVT-012", 150)
    };
    addEventsToEngine(events);

    size_t processed = engine.processPendingEvents();
    EXPECT_EQ(processed, 3);

    // 验证事件状态已更新
    const EventRecord* evt1 = engine.findEventById("EVT-010");
    ASSERT_NE(evt1, nullptr);
    EXPECT_EQ(evt1->status, EventStatus::Generated);

    const EventRecord* evt2 = engine.findEventById("EVT-011");
    ASSERT_NE(evt2, nullptr);
    EXPECT_EQ(evt2->status, EventStatus::Generated);

    // 验证生成了对应的 TaskPlan
    const std::vector<TaskPlan>& plans = engine.getAllPlans();
    EXPECT_EQ(plans.size(), 3);
    EXPECT_EQ(plans[0].relatedEventId, "EVT-010");
    EXPECT_EQ(plans[0].type, PlanType::Centralized);
    EXPECT_EQ(plans[0].status, PlanStatus::Drafting);
}

/**
 * @brief 测试 processPendingEvents 边界值：没有 Pending 事件
 */
TEST_F(CmsEngineTest, testProcessPendingEventsNoPending) {
    // 添加一个非 Pending 状态的事件
    EventRecord evt = createValidEvent("EVT-020", 100);
    evt.status = EventStatus::Generated;
    engine.ingestEvent(evt);

    size_t processed = engine.processPendingEvents();
    EXPECT_EQ(processed, 0);

    // 验证没有生成新的 TaskPlan
    const std::vector<TaskPlan>& plans = engine.getAllPlans();
    EXPECT_EQ(plans.size(), 0);
}

/**
 * @brief 测试 processPendingEvents 边界值：空事件库
 */
TEST_F(CmsEngineTest, testProcessPendingEventsEmpty) {
    size_t processed = engine.processPendingEvents();
    EXPECT_EQ(processed, 0);

    const std::vector<TaskPlan>& plans = engine.getAllPlans();
    EXPECT_EQ(plans.size(), 0);
}

/**
 * @brief 测试 processPendingEvents 特殊场景：混合状态的事件
 */
TEST_F(CmsEngineTest, testProcessPendingEventsMixedStatus) {
    EventRecord evt1 = createValidEvent("EVT-030", 100);
    evt1.status = EventStatus::Pending;
    engine.ingestEvent(evt1);

    EventRecord evt2 = createValidEvent("EVT-031", 200);
    evt2.status = EventStatus::Generated;
    engine.ingestEvent(evt2);

    EventRecord evt3 = createValidEvent("EVT-032", 150);
    evt3.status = EventStatus::Pending;
    engine.ingestEvent(evt3);

    size_t processed = engine.processPendingEvents();
    EXPECT_EQ(processed, 2);

    // 验证只有 Pending 的事件被处理
    const EventRecord* evt1_after = engine.findEventById("EVT-030");
    ASSERT_NE(evt1_after, nullptr);
    EXPECT_EQ(evt1_after->status, EventStatus::Generated);

    const EventRecord* evt2_after = engine.findEventById("EVT-031");
    ASSERT_NE(evt2_after, nullptr);
    EXPECT_EQ(evt2_after->status, EventStatus::Generated);

    const EventRecord* evt3_after = engine.findEventById("EVT-032");
    ASSERT_NE(evt3_after, nullptr);
    EXPECT_EQ(evt3_after->status, EventStatus::Generated);

    // 验证生成了 2 个 TaskPlan
    const std::vector<TaskPlan>& plans = engine.getAllPlans();
    EXPECT_EQ(plans.size(), 2);
}

// ============================================================================
// findEventById 测试用例
// ============================================================================

/**
 * @brief 测试 findEventById 正常输入：查找已存在的事件
 */
TEST_F(CmsEngineTest, testFindEventByIdExisting) {
    EventRecord evt = createValidEvent("EVT-100", 100);
    engine.ingestEvent(evt);

    const EventRecord* found = engine.findEventById("EVT-100");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->id, "EVT-100");
    EXPECT_EQ(found->priority, 100);
    EXPECT_EQ(found->status, EventStatus::Pending);
}

/**
 * @brief 测试 findEventById 边界值：查找空字符串 ID
 */
TEST_F(CmsEngineTest, testFindEventByIdEmptyString) {
    // 添加一个空 ID 的事件（虽然 ingestEvent 会拒绝，但直接测试 findEventById）
    const EventRecord* found = engine.findEventById("");
    EXPECT_EQ(found, nullptr);
}

/**
 * @brief 测试 findEventById 异常输入：查找不存在的事件
 */
TEST_F(CmsEngineTest, testFindEventByIdNonExistent) {
    EventRecord evt = createValidEvent("EVT-200", 100);
    engine.ingestEvent(evt);

    const EventRecord* found = engine.findEventById("EVT-999");
    EXPECT_EQ(found, nullptr);
}

/**
 * @brief 测试 findEventById 特殊场景：查找长 ID 字符串
 */
TEST_F(CmsEngineTest, testFindEventByIdLongId) {
    std::string longId = "EVT-" + std::string(100, 'A');
    EventRecord evt = createValidEvent(longId, 100);
    engine.ingestEvent(evt);

    const EventRecord* found = engine.findEventById(longId);
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->id, longId);
}

/**
 * @brief 测试 findEventById 特殊场景：多个事件中查找特定 ID
 */
TEST_F(CmsEngineTest, testFindEventByIdAmongMultiple) {
    std::vector<EventRecord> events = {
        createValidEvent("EVT-300", 100),
        createValidEvent("EVT-301", 200),
        createValidEvent("EVT-302", 150)
    };
    addEventsToEngine(events);

    // 查找中间的事件
    const EventRecord* found = engine.findEventById("EVT-301");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->id, "EVT-301");
    EXPECT_EQ(found->priority, 200);

    // 查找第一个事件
    found = engine.findEventById("EVT-300");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->id, "EVT-300");

    // 查找最后一个事件
    found = engine.findEventById("EVT-302");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->id, "EVT-302");
}

/**
 * @brief 测试 findEventById 特殊场景：查找已处理事件的状态
 */
TEST_F(CmsEngineTest, testFindEventByIdAfterProcessing) {
    EventRecord evt = createValidEvent("EVT-400", 100);
    engine.ingestEvent(evt);

    // 处理事件
    engine.processPendingEvents();

    // 查找事件并验证状态已更新
    const EventRecord* found = engine.findEventById("EVT-400");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->status, EventStatus::Generated);
}