#include <iostream>
#include <fstream>
#include <string>
#include <stdexcept>
#include <ctime>
#include <vector>
#include <sstream>
#include <limits>

class MathUtils {
public:
    static int add(int a, int b) {
        return a + b;
    }
    
    static bool validateInput(int num) {
        return num >= 0 && num <= 10000;
    }
};

class Logger {
private:
    std::string filename;
    
public:
    Logger(const std::string& fname) : filename(fname) {}
    
    void log(const std::string& message) {
        std::ofstream file(filename, std::ios::app);
        if (file.is_open()) {
            time_t now = time(0);
            file << "[" << ctime(&now) << "] " << message << "\n";
        }
    }
    
    std::vector<std::string> readLogs() {
        std::vector<std::string> logs;
        std::ifstream file(filename);
        if (file.is_open()) {
            std::string line;
            while (getline(file, line)) {
                logs.push_back(line);
            }
        }
        return logs;
    }
};

class InputHandler {
public:
    static int getInteger(const std::string& prompt) {
        int value;
        while (true) {
            std::cout << prompt;
            if (std::cin >> value) {
                if (MathUtils::validateInput(value)) {
                    break;
                } else {
                    std::cout << "输入必须在0-10000范围内\n";
                }
            } else {
                std::cin.clear();
                std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
                std::cout << "无效输入，请输入整数\n";
            }
        }
        return value;
    }
};

class TestRunner {
public:
    static void runTests() {
        testAddition();
        testInputValidation();
        std::cout << "所有测试通过\n";
    }
    
private:
    static void testAddition() {
        if (MathUtils::add(2, 3) != 5) {
            throw std::runtime_error("加法测试失败");
        }
        if (MathUtils::add(0, 0) != 0) {
            throw std::runtime_error("零加法测试失败");
        }
    }
    
    static void testInputValidation() {
        if (!MathUtils::validateInput(5000)) {
            throw std::runtime_error("输入验证测试失败");
        }
        if (MathUtils::validateInput(-1)) {
            throw std::runtime_error("负输入验证测试失败");
        }
    }
};

void displayMenu() {
    std::cout << "\n===== 高级加法计算器 =====\n";
    std::cout << "1. 计算两个数的和\n";
    std::cout << "2. 查看计算历史\n";
    std::cout << "3. 运行测试\n";
    std::cout << "4. 退出\n";
    std::cout << "选择: ";
}

int main() {
    Logger logger("calculator.log");
    
    while (true) {
        displayMenu();
        int choice;
        std::cin >> choice;
        
        try {
            switch (choice) {
                case 1: {
                    int a = InputHandler::getInteger("输入第一个数: ");
                    int b = InputHandler::getInteger("输入第二个数: ");
                    int result = MathUtils::add(a, b);
                    
                    std::ostringstream oss;
                    oss << a << " + " << b << " = " << result;
                    logger.log(oss.str());
                    
                    std::cout << "结果: " << oss.str() << "\n";
                    break;
                }
                case 2: {
                    auto logs = logger.readLogs();
                    std::cout << "\n=== 计算历史 ===\n";
                    for (const auto& log : logs) {
                        std::cout << log << "\n";
                    }
                    break;
                }
                case 3:
                    TestRunner::runTests();
                    break;
                case 4:
                    return 0;
                default:
                    std::cout << "无效选择\n";
            }
        } catch (const std::exception& e) {
            std::cerr << "错误: " << e.what() << "\n";
            logger.log(std::string("错误: ") + e.what());
        }
    }
}