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

// ============================================================================
// Test Fixture for CmsEngine
// ============================================================================
class CmsEngineTest : public ::testing::Test {
protected:
    void SetUp() override {
        // 在每个测试用例之前创建一个新的 CmsEngine 实例
        engine = new CmsEngine();
    }

    void TearDown() override {
        delete engine;
    }

    CmsEngine* engine;
};

// ============================================================================
// Tests for ingestEvent
// ============================================================================

/**
 * @brief 测试 ingestEvent 正常输入场景
 *
 * 验证一个有效的事件（非空 ID，优先级 <= 255）可以被成功接入。
 */
TEST_F(CmsEngineTest, testIngestEventNormal) {
    EventRecord event;
    event.id = "EVT-001";
    event.priority = 100;
    event.status = EventStatus::Pending;

    bool result = engine->ingestEvent(event);
    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 空 ID 场景
 *
 * 验证空 ID 的事件会被拒绝接入。
 */
TEST_F(CmsEngineTest, testIngestEventEmptyId) {
    EventRecord event;
    event.id = "";
    event.priority = 100;

    bool result = engine->ingestEvent(event);
    EXPECT_FALSE(result);

    // 验证事件未被存储
    const EventRecord* found = engine->findEventById("");
    EXPECT_EQ(found, nullptr);
}

/**
 * @brief 测试 ingestEvent 优先级边界值场景
 *
 * 验证优先级为 0（最小值）和 255（最大值）的事件可以被接入。
 */
TEST_F(CmsEngineTest, testIngestEventPriorityBoundary) {
    // 测试优先级为 0
    EventRecord event1;
    event1.id = "EVT-002";
    event1.priority = 0;
    EXPECT_TRUE(engine->ingestEvent(event1));

    // 测试优先级为 255
    EventRecord event2;
    event2.id = "EVT-003";
    event2.priority = 255;
    EXPECT_TRUE(engine->ingestEvent(event2));

    // 验证两个事件都已存储
    EXPECT_NE(engine->findEventById("EVT-002"), nullptr);
    EXPECT_NE(engine->findEventById("EVT-003"), nullptr);
}

/**
 * @brief 测试 ingestEvent 优先级越界场景
 *
 * 验证优先级超过 255 的事件会被拒绝接入。
 */
TEST_F(CmsEngineTest, testIngestEventPriorityOverflow) {
    EventRecord event;
    event.id = "EVT-004";
    event.priority = 256;  // 超过最大值

    bool result = engine->ingestEvent(event);
    EXPECT_FALSE(result);

    // 验证事件未被存储
    const EventRecord* found = engine->findEventById("EVT-004");
    EXPECT_EQ(found, nullptr);
}

/**
 * @brief 测试 ingestEvent 优先级为负数场景
 *
 * 验证优先级为负数的事件可以被接入（因为负数小于 255）。
 */
TEST_F(CmsEngineTest, testIngestEventNegativePriority) {
    EventRecord event;
    event.id = "EVT-005";
    event.priority = -1;  // 负数，但小于 255

    bool result = engine->ingestEvent(event);
    EXPECT_TRUE(result);

    // 验证事件已存储
    const EventRecord* found = engine->findEventById("EVT-005");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->priority, -1);
}

/**
 * @brief 测试 ingestEvent 多次接入相同 ID 事件场景
 *
 * 验证相同 ID 的事件可以被多次接入（事件库允许重复 ID）。
 */
TEST_F(CmsEngineTest, testIngestEventDuplicateId) {
    EventRecord event1;
    event1.id = "EVT-006";
    event1.priority = 50;
    EXPECT_TRUE(engine->ingestEvent(event1));

    EventRecord event2;
    event2.id = "EVT-006";  // 相同 ID
    event2.priority = 100;
    EXPECT_TRUE(engine->ingestEvent(event2));

    // 验证 findEventById 返回第一个匹配的事件
    const EventRecord* found = engine->findEventById("EVT-006");
    ASSERT_NE(found, nullptr);
    EXPECT_EQ(found->priority, 50);  // 返回第一个
}

// ============================================================================
// Tests for processPendingEvents
// ============================================================================

/**
 * @brief 测试 processPendingEvents 正常处理场景
 *
 * 验证 Pending 状态的事件会被正确处理并生成 TaskPlan。
 */
TEST_F(CmsEngineTest, testProcessPendingEventsNormal) {
    // 添加一个 Pending 事件
    EventRecord event;
    event.id = "EVT-010";
    event.priority = 100;
    event.status = EventStatus::Pending;
    engine->ingestEvent(event);

    size_t processed = engine->processPendingEvents();
    EXPECT_EQ(processed, 1);

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

    // 验证生成了一个 TaskPlan
    const auto& plans = engine->getAllPlans();
    ASSERT_EQ(plans.size(), 1);
    EXPECT_EQ(plans[0].name, "AutoPlan-EVT-010");
    EXPECT_EQ(plans[0].type, PlanType::Centralized);
    EXPECT_EQ(plans[0].status, PlanStatus::Drafting);
    EXPECT_EQ(plans[0].relatedEventId, "EVT-010");
    EXPECT_EQ(plans[0].resourceQuota, 0.5);
    EXPECT_EQ(plans[0].constraints, "自动生成约束");
}

/**
 * @brief 测试 processPendingEvents 无 Pending 事件场景
 *
 * 验证当没有 Pending 事件时，返回 0 且不生成 TaskPlan。
 */
TEST_F(CmsEngineTest, testProcessPendingEventsNoPending) {
    // 添加一个非 Pending 事件
    EventRecord event;
    event.id = "EVT-011";
    event.priority = 100;
    event.status = EventStatus::Generated;  // 不是 Pending
    engine->ingestEvent(event);

    size_t processed = engine->processPendingEvents();
    EXPECT_EQ(processed, 0);

    // 验证事件状态未改变
    const EventRecord* foundEvent = engine->findEventById("EVT-011");
    ASSERT_NE(foundEvent, nullptr);
    EXPECT_EQ(foundEvent->status, EventStatus::Generated);

    // 验证没有生成 TaskPlan
    const auto& plans = engine->getAllPlans();
    EXPECT_EQ(plans.size(), 0);
}

/**
 * @brief 测试 processPendingEvents 多个 Pending 事件场景
 *
 * 验证多个 Pending 事件都会被处理并生成对应的 TaskPlan。
 */
TEST_F(CmsEngineTest, testProcessPendingEventsMultiple) {
    // 添加三个 Pending 事件
    for (int i = 0; i < 3; ++i) {
        EventRecord event;
        event.id = "EVT-0" + std::to_string(i + 1);
        event.priority = 50 + i * 10;
        event.status = EventStatus::Pending;
        engine->ingestEvent(event);
    }

    size_t processed = engine->processPendingEvents();
    EXPECT_EQ(processed, 3);

    // 验证所有事件状态已更新
    for (int i = 0; i < 3; ++i) {
        std::string eventId = "EVT-0" + std::to_string(i + 1);
        const EventRecord* foundEvent = engine->findEventById(eventId);
        ASSERT_NE(foundEvent, nullptr);
        EXPECT_EQ(foundEvent->status, EventStatus::Generated);
    }

    // 验证生成了三个 TaskPlan
    const auto& plans = engine->getAllPlans();
    ASSERT_EQ(plans.size(), 3);
    for (int i = 0; i < 3; ++i) {
        std::string eventId = "EVT-0" + std::to_string(i + 1);
        EXPECT_EQ(plans[i].name, "AutoPlan-" + eventId);
        EXPECT_EQ(plans[i].relatedEventId, eventId);
    }
}

/**
 * @brief 测试 processPendingEvents 混合状态事件场景
 *
 * 验证只有 Pending 状态的事件被处理，其他状态的事件被忽略。
 */
TEST_F(CmsEngineTest, testProcessPendingEventsMixedStatus) {
    // 添加一个 Pending 事件
    EventRecord pendingEvent;
    pendingEvent.id = "EVT-020";
    pendingEvent.priority = 100;
    pendingEvent.status = EventStatus::Pending;
    engine->ingestEvent(pendingEvent);

    // 添加一个 Generated 事件
    EventRecord generatedEvent;
    generatedEvent.id = "EVT-021";
    generatedEvent.priority = 100;
    generatedEvent.status = EventStatus::Generated;
    engine->ingestEvent(generatedEvent);

    size_t processed = engine->processPendingEvents();
    EXPECT_EQ(processed, 1);

    // 验证只有 Pending 事件被处理
    const EventRecord* foundPending = engine->findEventById("EVT-020");
    ASSERT_NE(foundPending, nullptr);
    EXPECT_EQ(foundPending->status, EventStatus::Generated);

    const EventRecord* foundGenerated = engine->findEventById("EVT-021");
    ASSERT_NE(foundGenerated, nullptr);
    EXPECT_EQ(foundGenerated->status, EventStatus::Generated);  // 未改变

    // 验证只生成了一个 TaskPlan
    const auto& plans = engine->getAllPlans();
    ASSERT_EQ(plans.size(), 1);
    EXPECT_EQ(plans[0].relatedEventId, "EVT-020");
}

/**
 * @brief 测试 processPendingEvents 空事件库场景
 *
 * 验证当事件库为空时，返回 0 且不生成 TaskPlan。
 */
TEST_F(CmsEngineTest, testProcessPendingEventsEmpty) {
    size_t processed = engine->processPendingEvents();
    EXPECT_EQ(processed, 0);

    const auto& plans = engine->getAllPlans();
    EXPECT_EQ(plans.size(), 0);
}

/**
 * @brief 测试 processPendingEvents 生成 ID 唯一性场景
 *
 * 验证每次生成的 TaskPlan ID 是唯一的。
 */
TEST_F(CmsEngineTest, testProcessPendingEventsUniqueIds) {
    // 添加两个 Pending 事件
    EventRecord event1;
    event1.id = "EVT-030";
    event1.priority = 100;
    event1.status = EventStatus::Pending;
    engine->ingestEvent(event1);

    EventRecord event2;
    event2.id = "EVT-031";
    event2.priority = 100;
    event2.status = EventStatus::Pending;
    engine->ingestEvent(event2);

    engine->processPendingEvents();

    const auto& plans = engine->getAllPlans();
    ASSERT_EQ(plans.size(), 2);
    EXPECT_NE(plans[0].id, plans[1].id);  // ID 必须唯一
}

/**
 * @brief 测试 processPendingEvents 多次调用场景
 *
 * 验证多次调用 processPendingEvents 不会重复处理已处理的事件。
 */
TEST_F(CmsEngineTest, testProcessPendingEventsMultipleCalls) {
    // 添加一个 Pending 事件
    EventRecord event;
    event.id = "EVT-040";
    event.priority = 100;
    event.status = EventStatus::Pending;
    engine->ingestEvent(event);

    // 第一次调用
    size_t first = engine->processPendingEvents();
    EXPECT_EQ(first, 1);

    // 第二次调用（应该没有 Pending 事件了）
    size_t second = engine->processPendingEvents();
    EXPECT_EQ(second, 0);

    // 验证只生成了一个 TaskPlan
    const auto& plans = engine->getAllPlans();
    ASSERT_EQ(plans.size(), 1);
}