#include <iostream>
#include <string>
#include <sstream>
#include <cstdlib>

#include "auth_manager.h"
#include "session_manager.h"
#include "file_manager.h"

// 显示欢迎界面
void ShowWelcome() {
    std::cout << "=====================================" << std::endl;
    std::cout << "     中小学数学卷子自动生成系统" << std::endl;
    std::cout << "=====================================" << std::endl;
}

// 显示主菜单
void ShowMainMenu(const std::string& username, const std::string& difficulty) {
    std::cout << "\n=====================================" << std::endl;
    std::cout << "当前用户: " << username << " (" << difficulty << "老师)" << std::endl;
    std::cout << "当前出题类型: " << difficulty << std::endl;
    std::cout << "=====================================" << std::endl;
    std::cout << "请选择操作:" << std::endl;
    std::cout << "1. 生成题目（输入题目数量 10-30）" << std::endl;
    std::cout << "2. 切换难度（输入：切换为小学/初中/高中）" << std::endl;
    std::cout << "3. 退出登录（输入：-1）" << std::endl;
    std::cout << "> ";
}

int main() {
    AuthManager auth_manager;
    SessionManager session_manager;
    FileManager file_manager;
    
    while (true) {
        ShowWelcome();
        std::cout << "请输入用户名和密码（格式：用户名 密码），或输入 quit 退出系统：" << std::endl;  // 修改提示
        std::cout << "> ";
        
        std::string input;
        std::getline(std::cin, input);
        
        // 去除前后空格
        input.erase(0, input.find_first_not_of(" "));
        input.erase(input.find_last_not_of(" ") + 1);
        
        // 检查是否要退出系统（只在首页）
        if (input == "quit" || input == "exit" || input == "退出") {
            std::cout << "感谢使用中小学数学卷子自动生成系统，再见！" << std::endl;
            break;  // 退出整个程序
        }
        
        std::istringstream iss(input);
        std::string username, password;
        iss >> username >> password;
        
        // 检查输入格式
        if (username.empty() || password.empty()) {
            std::cout << "请输入正确的用户名、密码" << std::endl;
            continue;
        }
        
        // 检查是否正好有两个token
        std::vector<std::string> tokens;
        std::string token;
        while (iss >> token) {
            tokens.push_back(token);
        }

        if (!tokens.empty()) {  // 如果还有更多token，说明输入格式错误
            std::cout << "输入格式错误：请输入用户名和密码，用空格分隔" << std::endl;
            continue;
        }

        std::string user_type;
        if (auth_manager.Authenticate(username, password, &user_type)) {
            const char* difficulty_name = 
                (user_type == "primary") ? "小学" :
                (user_type == "junior") ? "初中" : "高中";
            
            std::cout << "登录成功！当前选择为" << difficulty_name << "出题" << std::endl;
            
            session_manager.SetUser(username, user_type);
            file_manager.CreateUserDirectory(username);
            
            // 主循环
            bool logged_in = true;
            while (logged_in) {
                ShowMainMenu(username, session_manager.GetCurrentDifficulty());
                
                std::string command;
                std::getline(std::cin, command);
                
                // 去除前后空格
                command.erase(0, command.find_first_not_of(" "));
                command.erase(command.find_last_not_of(" ") + 1);
                
                if (command.empty()) {
                    continue;
                }
                
                // 首先检查退出命令
                if (command == "-1") {
                    std::cout << "退出当前用户，重新登录..." << std::endl;
                    logged_in = false;
                    continue;
                }
                
                // 检查切换难度命令
                if (command.find("切换为") == 0) {
                    std::string new_difficulty = command.substr(9);
                    
                    if (new_difficulty == "小学" || new_difficulty == "初中" || new_difficulty == "高中") {
                        std::string difficulty_type = 
                            (new_difficulty == "小学") ? "primary" :
                            (new_difficulty == "初中") ? "junior" : "senior";
                        
                        if (session_manager.SwitchDifficulty(difficulty_type)) {
                            std::cout << "切换成功！当前出题类型: " << new_difficulty << std::endl;
                        }
                    } else {
                        std::cout << "请输入小学、初中和高中三个选项中的一个" << std::endl;
                    }
                    continue;
                }
                
                // 尝试解析为数字（题目数量）
                try {
                    int count = std::stoi(command);
                    if (count >= 10 && count <= 30) {
                        std::cout << "正在生成" << session_manager.GetCurrentDifficulty() 
                                  << "数学题目，数量: " << count << "..." << std::endl;
                        
                        QuestionGenerator* generator = session_manager.GetCurrentGenerator();
                        auto questions = generator->GenerateQuestions(count, username);
                        
                        if (file_manager.SaveQuestions(username, questions)) {
                            std::cout << "题目生成完成！已保存到文件。" << std::endl;
                        } else {
                            std::cout << "文件保存失败！" << std::endl;
                        }
                    } else {
                        std::cout << "题目数量范围应为10-30，请重新输入" << std::endl;
                    }
                } catch (const std::exception& e) {
                    std::cout << "无效命令，请重新输入" << std::endl;
                    std::cout << "有效命令：10-30（生成题目）、-1（退出登录）、切换为小学/初中/高中" << std::endl;
                }
            }
        } else {
            std::cout << "请输入正确的用户名、密码" << std::endl;
        }
    }
    
    return 0;
}