#include <graphics.h>
#include <conio.h>
#include <iostream>
#include <string.h>
#include <vector>
#include <algorithm>
#include <string>
#include <sstream>
#include <windows.h>
#include <tchar.h>
using namespace std;

// 全局常量定义
#define WIN_WIDTH 800
#define WIN_HEIGHT 600
#define FONT_SIZE 16
#define COLOR_BG RGB(245, 245, 245)       // 背景色
#define COLOR_MENU RGB(60, 179, 113)      // 菜单底色
#define COLOR_TEXT RGB(255, 255, 255)     // 文字白色
#define COLOR_BLACK RGB(0, 0, 0)          // 黑色
#define COLOR_RED RGB(255, 0, 0)          // 红色
#define COLOR_BLUE RGB(0, 0, 255)         // 蓝色

// 输入焦点枚举（统一管理所有输入框焦点）
enum InputFocusType {
    FOCUS_NONE,        // 无焦点
    FOCUS_LOGIN_PWD,   // 登录密码框
    FOCUS_COURSE_NUM,  // 课程编号（添加/修改）
    FOCUS_COURSE_NAME, // 课程名称
    FOCUS_COURSE_CREDIT,// 课程学分
    FOCUS_COURSE_TEACHER,// 授课教师
    FOCUS_DEL_COURSE_NUM,// 删除课程编号
    FOCUS_EDIT_COURSE_NUM,// 修改课程-查询编号
    FOCUS_STU_NUM,     // 学生学号
    FOCUS_STU_NAME,    // 学生姓名
    FOCUS_STU_SEX,     // 学生性别
    FOCUS_STU_GRADE,   // 学生年级
    FOCUS_STU_SELECT_STU_NUM,// 选课-学生学号
    FOCUS_STU_SELECT_COURSE_NUM,// 选课-课程编号
    FOCUS_CHANGE_PWD1, // 修改密码-新密码
    FOCUS_CHANGE_PWD2  // 修改密码-确认密码
};

// 全局变量
string adminPwd = "1234";                // 管理员密码
bool isLogin = false;                     // 登录状态
string inputBuffer = "";                  // 通用输入缓冲区
string tempStr1 = "";                     // 临时输入1（课程名称/学生姓名等）
string tempStr2 = "";                     // 临时输入2（学分/性别等）
string tempStr3 = "";                     // 临时输入3（教师/年级等）
int currentMenu = 0;                      // 当前菜单：0-登录 1-主菜单 2-课程管理 3-学生管理
InputFocusType currentFocus = FOCUS_NONE; // 当前输入焦点
DWORD lastCursorTime = 0;                 // 光标闪烁计时
bool showCursor = true;                   // 光标显示状态
// 键盘输入防抖标记
bool keyBackPressed = false;
bool keyEnterPressed = false;
bool charKeysPressed[95] = { false };       // 32-126可打印字符防抖

// 信息基类
class info {
protected:
    long number;    // 编号
    string name;    // 名称
public:
    info() {}
    info(long num, string name) : number(num), name(name) {}
    long getNumber() { return number; }
    string getName() { return name; }
    void setName(string n) { name = n; }
};

// 课程类
class course : public info {
private:
    int credit;             // 学分
    string teachername;     // 授课教师
public:
    course() {}
    course(long num, string name, int cre, string tea) : info(num, name) {
        credit = cre;
        teachername = tea;
    }
    int getCredit() { return credit; }
    string getTeacher() { return teachername; }
    void setCredit(int c) { credit = c; }
    void setTeacher(string t) { teachername = t; }

    // 静态方法声明
    static void addCourse(long num, string name, int cre, string tea);
    static void delCourse(long num);
    static void editCourse(long num, string name, int cre, string tea);
    static bool isHave(long num);
    static course* getCourse(long num);
    static vector<course>& getCourseList();
};

// 学生类
class student : public info {
private:
    string sex;          // 性别
    string grade;        // 年级
    long scredit;        // 总学分
    vector<course> havec;// 已选课程
public:
    student() {}
    student(long num, string name, string se, string gra, long scr = 0) : info(num, name) {
        sex = se;
        grade = gra;
        scredit = scr;
    }

    string getSex() { return sex; }
    string getGrade() { return grade; }
    long getSCredit() { return scredit; }
    vector<course>& getHaveC() { return havec; }
    void setSex(string s) { sex = s; }
    void setGrade(string g) { grade = g; }
    void setSCredit(long sc) { scredit = sc; }

    // 静态方法声明
    static void addStudent(long num, string name, string se, string gra);
    static void delStudent(long num);
    static void editStudent(long num, string name, string se, string gra);
    static bool isHave(long num);
    static student* getStudent(long num);
    static vector<student>& getStudentList();
    static void addCourseToStudent(long stuNum, long courseNum);
    static void delCourseFromStudent(long stuNum, long courseNum);
};

// 全局容器
vector<course> courseList;
vector<student> studentList;

// 课程类静态方法实现
vector<course>& course::getCourseList() { return courseList; }
void course::addCourse(long num, string name, int cre, string tea) {
    courseList.push_back(course(num, name, cre, tea));
}
void course::delCourse(long num) {
    for (auto it = courseList.begin(); it != courseList.end(); it++) {
        if (it->getNumber() == num) {
            courseList.erase(it);
            break;
        }
    }
}
void course::editCourse(long num, string name, int cre, string tea) {
    for (auto& c : courseList) {
        if (c.getNumber() == num) {
            if (!name.empty()) c.setName(name);
            if (cre > 0) c.setCredit(cre);
            if (!tea.empty()) c.setTeacher(tea);
            break;
        }
    }
}
bool course::isHave(long num) {
    for (auto& c : courseList) {
        if (c.getNumber() == num) return true;
    }
    return false;
}
course* course::getCourse(long num) {
    for (auto& c : courseList) {
        if (c.getNumber() == num) return &c;
    }
    return nullptr;
}

// 学生类静态方法实现
vector<student>& student::getStudentList() { return studentList; }
void student::addStudent(long num, string name, string se, string gra) {
    studentList.push_back(student(num, name, se, gra));
}
void student::delStudent(long num) {
    for (auto it = studentList.begin(); it != studentList.end(); it++) {
        if (it->getNumber() == num) {
            studentList.erase(it);
            break;
        }
    }
}
void student::editStudent(long num, string name, string se, string gra) {
    for (auto& s : studentList) {
        if (s.getNumber() == num) {
            if (!name.empty()) s.setName(name);
            if (!se.empty()) s.setSex(se);
            if (!gra.empty()) s.setGrade(gra);
            break;
        }
    }
}
bool student::isHave(long num) {
    for (auto& s : studentList) {
        if (s.getNumber() == num) return true;
    }
    return false;
}
student* student::getStudent(long num) {
    for (auto& s : studentList) {
        if (s.getNumber() == num) return &s;
    }
    return nullptr;
}
void student::addCourseToStudent(long stuNum, long courseNum) {
    student* stu = getStudent(stuNum);
    course* crs = course::getCourse(courseNum);
    if (stu && crs) {
        // 检查是否已选
        for (auto& c : stu->getHaveC()) {
            if (c.getNumber() == courseNum) return;
        }
        stu->getHaveC().push_back(*crs);
    }
}
void student::delCourseFromStudent(long stuNum, long courseNum) {
    student* stu = getStudent(stuNum);
    if (stu) {
        for (auto it = stu->getHaveC().begin(); it != stu->getHaveC().end(); it++) {
            if (it->getNumber() == courseNum) {
                stu->getHaveC().erase(it);
                break;
            }
        }
    }
}

// 工具函数：绘制按钮
void drawButton(int x, int y, int w, int h, const TCHAR* text, COLORREF bgColor, COLORREF textColor) {
    setfillcolor(bgColor);
    solidroundrect(x, y, x + w, y + h, 10, 10);
    settextcolor(textColor);
    setbkmode(TRANSPARENT);
    settextstyle(FONT_SIZE, 0, _T("微软雅黑"));
    outtextxy(x + w / 2 - textwidth(text) / 2, y + h / 2 - textheight(text) / 2, text);
}

// 工具函数：检查鼠标是否点击按钮/输入框
bool isClickArea(int x, int y, int w, int h, int mouseX, int mouseY) {
    return (mouseX >= x && mouseX <= x + w && mouseY >= y && mouseY <= y + h);
}

// 工具函数：数字转字符串
string num2str(long num) {
    stringstream ss;
    ss << num;
    return ss.str();
}

// 工具函数：字符串转数字
long str2num(string str) {
    if (str.empty()) return 0;
    long num;
    stringstream ss(str);
    ss >> num;
    return num;
}

// 工具函数：更新光标闪烁状态
void updateCursor() {
    DWORD currentTime = GetTickCount();
    if (currentTime - lastCursorTime > 500) { // 500ms闪烁一次
        showCursor = !showCursor;
        lastCursorTime = currentTime;
    }
}

// 工具函数：绘制输入框（带焦点和光标）
void drawInputBox(int x, int y, int w, int h, const TCHAR* hint, string& inputStr, bool isFocused, bool isPassword = false) {
    // 绘制输入框边框
    setlinecolor(COLOR_BLACK);
    rectangle(x, y, x + w, y + h);

    // 绘制提示文字/输入内容
    settextcolor(isFocused ? COLOR_BLACK : RGB(160, 160, 160));
    settextstyle(FONT_SIZE, 0, _T("微软雅黑"));
    TCHAR showBuf[256] = { 0 };

    if (inputStr.empty()) {
        outtextxy(x + 10, y + h / 2 - textheight(hint) / 2, hint);
    }
    else {
        if (isPassword) {
            // 密码框显示星号
            string pwdStars(inputStr.length(), '*');
            MultiByteToWideChar(CP_ACP, 0, pwdStars.c_str(), -1, showBuf, 256);
        }
        else {
            MultiByteToWideChar(CP_ACP, 0, inputStr.c_str(), -1, showBuf, 256);
        }
        outtextxy(x + 10, y + h / 2 - textheight(showBuf) / 2, showBuf);
    }

    // 绘制闪烁光标（仅焦点时）
    if (isFocused && showCursor) {
        int cursorX = x + 10 + (inputStr.empty() ? textwidth(hint) : textwidth(showBuf)) + 2;
        line(cursorX, y + 5, cursorX, y + h - 5);
    }
}

// 工具函数：重置所有键盘防抖标记
void resetKeyFlags() {
    keyBackPressed = false;
    keyEnterPressed = false;
    memset(charKeysPressed, 0, sizeof(charKeysPressed));
}

// 工具函数：统一处理键盘输入（适配所有输入框）
void handleKeyboardInput() {
    // 退格键（所有焦点通用）- 防抖处理
    if ((GetAsyncKeyState(VK_BACK) & 0x8000) && !keyBackPressed) {
        keyBackPressed = true;
        switch (currentFocus) {
        case FOCUS_LOGIN_PWD: if (!inputBuffer.empty()) inputBuffer.pop_back(); break;
        case FOCUS_COURSE_NUM: if (!inputBuffer.empty()) inputBuffer.pop_back(); break;
        case FOCUS_COURSE_NAME: if (!tempStr1.empty()) tempStr1.pop_back(); break;
        case FOCUS_COURSE_CREDIT: if (!tempStr2.empty()) tempStr2.pop_back(); break;
        case FOCUS_COURSE_TEACHER: if (!tempStr3.empty()) tempStr3.pop_back(); break;
        case FOCUS_DEL_COURSE_NUM: if (!inputBuffer.empty()) inputBuffer.pop_back(); break;
        case FOCUS_EDIT_COURSE_NUM: if (!inputBuffer.empty()) inputBuffer.pop_back(); break;
        case FOCUS_STU_NUM: if (!inputBuffer.empty()) inputBuffer.pop_back(); break;
        case FOCUS_STU_NAME: if (!tempStr1.empty()) tempStr1.pop_back(); break;
        case FOCUS_STU_SEX: if (!tempStr2.empty()) tempStr2.pop_back(); break;
        case FOCUS_STU_GRADE: if (!tempStr3.empty()) tempStr3.pop_back(); break;
        case FOCUS_STU_SELECT_STU_NUM: if (!inputBuffer.empty()) inputBuffer.pop_back(); break;
        case FOCUS_STU_SELECT_COURSE_NUM: if (!tempStr1.empty()) tempStr1.pop_back(); break;
        case FOCUS_CHANGE_PWD1: if (!inputBuffer.empty()) inputBuffer.pop_back(); break;
        case FOCUS_CHANGE_PWD2: if (!tempStr1.empty()) tempStr1.pop_back(); break;
        default: break;
        }
    }
    else if (!(GetAsyncKeyState(VK_BACK) & 0x8000)) {
        keyBackPressed = false;
    }

    // 仅处理可打印字符（32-126）- 防抖处理
    for (int i = 0; i < 95; i++) {
        char c = 32 + i;
        if ((GetAsyncKeyState(c) & 0x8000) && !charKeysPressed[i]) {
            charKeysPressed[i] = true;
            // 根据焦点过滤字符类型
            switch (currentFocus) {
                // 仅允许数字
            case FOCUS_COURSE_NUM:
            case FOCUS_DEL_COURSE_NUM:
            case FOCUS_EDIT_COURSE_NUM:
            case FOCUS_STU_NUM:
            case FOCUS_STU_SELECT_STU_NUM:
            case FOCUS_STU_SELECT_COURSE_NUM:
            case FOCUS_COURSE_CREDIT:
                if (c >= '0' && c <= '9') {
                    if (currentFocus == FOCUS_COURSE_CREDIT) tempStr2 += c;
                    else inputBuffer += c;
                }
                break;
                // 允许所有字符（密码框/名称/性别等）
            case FOCUS_LOGIN_PWD: inputBuffer += c; break;
            case FOCUS_COURSE_NAME: tempStr1 += c; break;
            case FOCUS_COURSE_TEACHER: tempStr3 += c; break;
            case FOCUS_STU_NAME: tempStr1 += c; break;
            case FOCUS_STU_SEX: tempStr2 += c; break;
            case FOCUS_STU_GRADE: tempStr3 += c; break;
            case FOCUS_CHANGE_PWD1: inputBuffer += c; break;
            case FOCUS_CHANGE_PWD2: tempStr1 += c; break;
            default: break;
            }
            break;
        }
        else if (!(GetAsyncKeyState(c) & 0x8000)) {
            charKeysPressed[i] = false;
        }
    }
}

// 登录界面
void drawLogin() {
    BeginBatchDraw();
    cleardevice();
    setbkcolor(COLOR_BG);

    // 绘制标题
    settextcolor(COLOR_MENU);
    settextstyle(30, 0, _T("微软雅黑"));
    const TCHAR* title = _T("学生选课管理系统-管理员端");
    outtextxy(WIN_WIDTH / 2 - textwidth(title) / 2, 100, title);

    // 绘制密码输入框
    int inputX = WIN_WIDTH / 2 - 150;
    int inputY = 200;
    int inputW = 300;
    int inputH = 40;

    drawInputBox(inputX, inputY, inputW, inputH, _T("请输入管理员密码"), inputBuffer, currentFocus == FOCUS_LOGIN_PWD, true);

    // 绘制登录按钮
    drawButton(WIN_WIDTH / 2 - 80, 280, 160, 40, _T("登录"), COLOR_MENU, COLOR_TEXT);

    // 处理鼠标事件
    if (MouseHit()) {
        MOUSEMSG msg = GetMouseMsg();
        if (msg.uMsg == WM_LBUTTONDOWN) {
            resetKeyFlags();
            if (isClickArea(WIN_WIDTH / 2 - 80, 280, 160, 40, msg.x, msg.y)) {
                if (inputBuffer == adminPwd) {
                    isLogin = true;
                    currentMenu = 1;
                    inputBuffer = "";
                    currentFocus = FOCUS_NONE;
                }
                else {
                    settextcolor(COLOR_RED);
                    const TCHAR* err = _T("密码错误！请输入1234");
                    outtextxy(WIN_WIDTH / 2 - textwidth(err) / 2, 350, err);
                    inputBuffer = "";
                }
                Sleep(200);
            }
            else if (isClickArea(inputX, inputY, inputW, inputH, msg.x, msg.y)) {
                currentFocus = FOCUS_LOGIN_PWD;
                lastCursorTime = GetTickCount();
            }
            else {
                currentFocus = FOCUS_NONE;
            }
        }
    }

    // 处理键盘输入
    if (currentFocus == FOCUS_LOGIN_PWD) {
        handleKeyboardInput();

        if ((GetAsyncKeyState(VK_RETURN) & 0x8000) && !keyEnterPressed) {
            keyEnterPressed = true;
            if (inputBuffer == adminPwd) {
                isLogin = true;
                currentMenu = 1;
                inputBuffer = "";
                currentFocus = FOCUS_NONE;
            }
            else {
                settextcolor(COLOR_RED);
                const TCHAR* err = _T("密码错误！请输入1234");
                outtextxy(WIN_WIDTH / 2 - textwidth(err) / 2, 350, err);
                inputBuffer = "";
            }
            Sleep(200);
        }
        else if (!(GetAsyncKeyState(VK_RETURN) & 0x8000)) {
            keyEnterPressed = false;
        }
    }

    FlushBatchDraw();
    EndBatchDraw();
    Sleep(10);
}

// 主菜单
void drawMainMenu() {
    BeginBatchDraw();
    cleardevice();
    setbkcolor(COLOR_BG);

    // 标题
    settextcolor(COLOR_MENU);
    settextstyle(30, 0, _T("微软雅黑"));
    const TCHAR* title = _T("主菜单");
    outtextxy(WIN_WIDTH / 2 - textwidth(title) / 2, 50, title);

    // 功能按钮
    drawButton(WIN_WIDTH / 2 - 100, 150, 200, 50, _T("课程信息管理"), COLOR_MENU, COLOR_TEXT);
    drawButton(WIN_WIDTH / 2 - 100, 230, 200, 50, _T("学生信息管理"), COLOR_MENU, COLOR_TEXT);
    drawButton(WIN_WIDTH / 2 - 100, 310, 200, 50, _T("修改密码"), COLOR_MENU, COLOR_TEXT);
    drawButton(WIN_WIDTH / 2 - 100, 390, 200, 50, _T("退出系统"), COLOR_MENU, COLOR_TEXT);

    // 处理鼠标事件
    if (MouseHit()) {
        MOUSEMSG msg = GetMouseMsg();
        if (msg.uMsg == WM_LBUTTONDOWN) {
            resetKeyFlags();
            currentFocus = FOCUS_NONE;
            if (isClickArea(WIN_WIDTH / 2 - 100, 150, 200, 50, msg.x, msg.y)) {
                currentMenu = 2;
                inputBuffer = tempStr1 = tempStr2 = tempStr3 = "";
            }
            else if (isClickArea(WIN_WIDTH / 2 - 100, 230, 200, 50, msg.x, msg.y)) {
                currentMenu = 3;
                inputBuffer = tempStr1 = tempStr2 = tempStr3 = "";
            }
            else if (isClickArea(WIN_WIDTH / 2 - 100, 310, 200, 50, msg.x, msg.y)) {
                // 修改密码逻辑
                inputBuffer = tempStr1 = "";
                bool waitInput = true;
                while (waitInput) {
                    BeginBatchDraw();
                    cleardevice();
                    settextcolor(COLOR_BLACK);

                    int pwd1X = 100, pwd1Y = 130;
                    int pwd2X = 100, pwd2Y = 220;
                    int pwdW = 200, pwdH = 40;

                    outtextxy(100, 100, _T("请输入新密码："));
                    drawInputBox(pwd1X, pwd1Y, pwdW, pwdH, _T("新密码"), inputBuffer, currentFocus == FOCUS_CHANGE_PWD1, true);

                    outtextxy(100, 190, _T("请确认新密码："));
                    drawInputBox(pwd2X, pwd2Y, pwdW, pwdH, _T("确认密码"), tempStr1, currentFocus == FOCUS_CHANGE_PWD2, true);

                    drawButton(100, 280, 100, 40, _T("确认"), COLOR_MENU, COLOR_TEXT);
                    drawButton(220, 280, 100, 40, _T("取消"), RGB(200, 200, 200), COLOR_BLACK);

                    FlushBatchDraw();
                    EndBatchDraw();

                    if (MouseHit()) {
                        MOUSEMSG msg2 = GetMouseMsg();
                        if (msg2.uMsg == WM_LBUTTONDOWN) {
                            resetKeyFlags();
                            if (isClickArea(pwd1X, pwd1Y, pwdW, pwdH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_CHANGE_PWD1;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(pwd2X, pwd2Y, pwdW, pwdH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_CHANGE_PWD2;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(100, 280, 100, 40, msg2.x, msg2.y)) {
                                if (inputBuffer == tempStr1 && !inputBuffer.empty()) {
                                    adminPwd = inputBuffer;
                                    cleardevice();
                                    outtextxy(100, 350, _T("密码修改成功！"));
                                    FlushBatchDraw();
                                }
                                else {
                                    cleardevice();
                                    outtextxy(100, 350, _T("两次密码不一致！"));
                                    FlushBatchDraw();
                                }
                                Sleep(1000);
                                waitInput = false;
                                currentMenu = 1;
                                currentFocus = FOCUS_NONE;
                            }
                            else if (isClickArea(220, 280, 100, 40, msg2.x, msg2.y)) {
                                waitInput = false;
                                currentMenu = 1;
                                currentFocus = FOCUS_NONE;
                            }
                        }
                    }

                    handleKeyboardInput();
                    updateCursor();
                    Sleep(10);
                }
            }
            else if (isClickArea(WIN_WIDTH / 2 - 100, 390, 200, 50, msg.x, msg.y)) {
                closegraph();
                exit(0);
            }
        }
    }

    FlushBatchDraw();
    EndBatchDraw();
    Sleep(10);
}

// 课程管理界面（核心修复：查看课程、修改课程功能）
void drawCourseMenu() {
    BeginBatchDraw();
    cleardevice();
    setbkcolor(COLOR_BG);

    // 标题与返回按钮
    settextcolor(COLOR_MENU);
    settextstyle(30, 0, _T("微软雅黑"));
    const TCHAR* title = _T("课程信息管理");
    outtextxy(WIN_WIDTH / 2 - textwidth(title) / 2, 30, title);
    drawButton(20, 20, 80, 30, _T("返回"), RGB(200, 200, 200), COLOR_BLACK);

    // 功能按钮
    drawButton(50, 100, 120, 40, _T("添加课程"), COLOR_MENU, COLOR_TEXT);
    drawButton(200, 100, 120, 40, _T("删除课程"), COLOR_MENU, COLOR_TEXT);
    drawButton(350, 100, 120, 40, _T("修改课程"), COLOR_MENU, COLOR_TEXT);
    drawButton(500, 100, 120, 40, _T("查看所有课程"), COLOR_MENU, COLOR_TEXT);

    // 处理鼠标事件
    if (MouseHit()) {
        MOUSEMSG msg = GetMouseMsg();
        if (msg.uMsg == WM_LBUTTONDOWN) {
            resetKeyFlags();
            currentFocus = FOCUS_NONE;
            if (isClickArea(20, 20, 80, 30, msg.x, msg.y)) {
                currentMenu = 1;
                inputBuffer = tempStr1 = tempStr2 = tempStr3 = "";
                return;
            }
            // 添加课程
            else if (isClickArea(50, 100, 120, 40, msg.x, msg.y)) {
                inputBuffer = tempStr1 = tempStr2 = tempStr3 = "";
                bool waitInput = true;
                while (waitInput) {
                    BeginBatchDraw();
                    cleardevice();
                    settextcolor(COLOR_BLACK);

                    int numX = 150, numY = 95;
                    int nameX = 150, nameY = 155;
                    int creditX = 150, creditY = 215;
                    int teacherX = 150, teacherY = 275;
                    int inputW = 200, inputH = 40;

                    outtextxy(50, 50, _T("添加课程"));
                    outtextxy(50, 100, _T("课程编号："));
                    drawInputBox(numX, numY, inputW, inputH, _T("数字编号"), inputBuffer, currentFocus == FOCUS_COURSE_NUM);

                    outtextxy(50, 160, _T("课程名称："));
                    drawInputBox(nameX, nameY, inputW, inputH, _T("如：数据结构"), tempStr1, currentFocus == FOCUS_COURSE_NAME);

                    outtextxy(50, 220, _T("课程学分："));
                    drawInputBox(creditX, creditY, inputW, inputH, _T("数字"), tempStr2, currentFocus == FOCUS_COURSE_CREDIT);

                    outtextxy(50, 280, _T("授课教师："));
                    drawInputBox(teacherX, teacherY, inputW, inputH, _T("教师姓名"), tempStr3, currentFocus == FOCUS_COURSE_TEACHER);

                    drawButton(150, 350, 100, 40, _T("确认添加"), COLOR_MENU, COLOR_TEXT);
                    drawButton(270, 350, 100, 40, _T("取消"), RGB(200, 200, 200), COLOR_BLACK);

                    FlushBatchDraw();
                    EndBatchDraw();

                    if (MouseHit()) {
                        MOUSEMSG msg2 = GetMouseMsg();
                        if (msg2.uMsg == WM_LBUTTONDOWN) {
                            resetKeyFlags();
                            if (isClickArea(numX, numY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_COURSE_NUM;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(nameX, nameY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_COURSE_NAME;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(creditX, creditY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_COURSE_CREDIT;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(teacherX, teacherY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_COURSE_TEACHER;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(150, 350, 100, 40, msg2.x, msg2.y)) {
                                long num = str2num(inputBuffer);
                                int credit = str2num(tempStr2);
                                if (!course::isHave(num) && !inputBuffer.empty() && !tempStr1.empty()) {
                                    course::addCourse(num, tempStr1, credit, tempStr3);
                                    cleardevice();
                                    outtextxy(50, 420, _T("课程添加成功！"));
                                }
                                else {
                                    cleardevice();
                                    outtextxy(50, 420, _T("编号重复或信息为空！"));
                                }
                                FlushBatchDraw();
                                Sleep(1000);
                                waitInput = false;
                                currentMenu = 2;
                                currentFocus = FOCUS_NONE;
                            }
                            else if (isClickArea(270, 350, 100, 40, msg2.x, msg2.y)) {
                                waitInput = false;
                                currentMenu = 2;
                                currentFocus = FOCUS_NONE;
                            }
                        }
                    }

                    handleKeyboardInput();
                    updateCursor();
                    Sleep(10);
                }
            }
            // 删除课程
            else if (isClickArea(200, 100, 120, 40, msg.x, msg.y)) {
                inputBuffer = "";
                bool waitInput = true;
                while (waitInput) {
                    BeginBatchDraw();
                    cleardevice();
                    settextcolor(COLOR_BLACK);

                    int numX = 150, numY = 95;
                    int inputW = 200, inputH = 40;

                    outtextxy(50, 50, _T("删除课程"));
                    outtextxy(50, 100, _T("课程编号："));
                    drawInputBox(numX, numY, inputW, inputH, _T("输入要删除的编号"), inputBuffer, currentFocus == FOCUS_DEL_COURSE_NUM);

                    drawButton(150, 180, 100, 40, _T("确认删除"), COLOR_MENU, COLOR_TEXT);
                    drawButton(270, 180, 100, 40, _T("取消"), RGB(200, 200, 200), COLOR_BLACK);

                    FlushBatchDraw();
                    EndBatchDraw();

                    if (MouseHit()) {
                        MOUSEMSG msg2 = GetMouseMsg();
                        if (msg2.uMsg == WM_LBUTTONDOWN) {
                            resetKeyFlags();
                            if (isClickArea(numX, numY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_DEL_COURSE_NUM;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(150, 180, 100, 40, msg2.x, msg2.y)) {
                                long num = str2num(inputBuffer);
                                if (course::isHave(num)) {
                                    course::delCourse(num);
                                    cleardevice();
                                    outtextxy(50, 250, _T("课程删除成功！"));
                                }
                                else {
                                    cleardevice();
                                    outtextxy(50, 250, _T("课程不存在！"));
                                }
                                FlushBatchDraw();
                                Sleep(1000);
                                waitInput = false;
                                currentMenu = 2;
                                currentFocus = FOCUS_NONE;
                            }
                            else if (isClickArea(270, 180, 100, 40, msg2.x, msg2.y)) {
                                waitInput = false;
                                currentMenu = 2;
                                currentFocus = FOCUS_NONE;
                            }
                        }
                    }

                    handleKeyboardInput();
                    updateCursor();
                    Sleep(10);
                }
            }
            // 修改课程（新增完整逻辑）
            else if (isClickArea(350, 100, 120, 40, msg.x, msg.y)) {
                inputBuffer = tempStr1 = tempStr2 = tempStr3 = "";
                bool waitInput = true;
                bool isEditMode = false; // 是否进入编辑模式
                course* targetCourse = nullptr;

                while (waitInput) {
                    BeginBatchDraw();
                    cleardevice();
                    settextcolor(COLOR_BLACK);

                    if (!isEditMode) {
                        // 第一步：输入要修改的课程编号
                        int numX = 150, numY = 95;
                        int inputW = 200, inputH = 40;

                        outtextxy(50, 50, _T("修改课程-查询"));
                        outtextxy(50, 100, _T("课程编号："));
                        drawInputBox(numX, numY, inputW, inputH, _T("输入要修改的编号"), inputBuffer, currentFocus == FOCUS_EDIT_COURSE_NUM);

                        drawButton(150, 180, 100, 40, _T("查询"), COLOR_MENU, COLOR_TEXT);
                        drawButton(270, 180, 100, 40, _T("取消"), RGB(200, 200, 200), COLOR_BLACK);

                        // 显示提示
                        if (!inputBuffer.empty() && !course::isHave(str2num(inputBuffer))) {
                            settextcolor(COLOR_RED);
                            outtextxy(150, 240, _T("课程编号不存在！"));
                        }
                    }
                    else {
                        // 第二步：编辑课程信息（回显原有数据）
                        int numX = 150, numY = 95;
                        int nameX = 150, nameY = 155;
                        int creditX = 150, creditY = 215;
                        int teacherX = 150, teacherY = 275;
                        int inputW = 200, inputH = 40;

                        outtextxy(50, 50, _T("修改课程-编辑"));
                        outtextxy(50, 100, _T("课程编号："));
                        // 编号不可修改，仅显示
                        TCHAR numBuf[32] = { 0 };
                        MultiByteToWideChar(CP_ACP, 0, num2str(targetCourse->getNumber()).c_str(), -1, numBuf, 32);
                        rectangle(numX, numY, numX + inputW, numY + inputH);
                        outtextxy(numX + 10, numY + inputH / 2 - textheight(numBuf) / 2, numBuf);

                        outtextxy(50, 160, _T("课程名称："));
                        // 回显原有名称
                        if (tempStr1.empty()) tempStr1 = targetCourse->getName();
                        drawInputBox(nameX, nameY, inputW, inputH, _T("如：数据结构"), tempStr1, currentFocus == FOCUS_COURSE_NAME);

                        outtextxy(50, 220, _T("课程学分："));
                        // 回显原有学分
                        if (tempStr2.empty()) tempStr2 = num2str(targetCourse->getCredit());
                        drawInputBox(creditX, creditY, inputW, inputH, _T("数字"), tempStr2, currentFocus == FOCUS_COURSE_CREDIT);

                        outtextxy(50, 280, _T("授课教师："));
                        // 回显原有教师
                        if (tempStr3.empty()) tempStr3 = targetCourse->getTeacher();
                        drawInputBox(teacherX, teacherY, inputW, inputH, _T("教师姓名"), tempStr3, currentFocus == FOCUS_COURSE_TEACHER);

                        drawButton(150, 350, 100, 40, _T("确认修改"), COLOR_MENU, COLOR_TEXT);
                        drawButton(270, 350, 100, 40, _T("取消"), RGB(200, 200, 200), COLOR_BLACK);
                    }

                    FlushBatchDraw();
                    EndBatchDraw();

                    if (MouseHit()) {
                        MOUSEMSG msg2 = GetMouseMsg();
                        if (msg2.uMsg == WM_LBUTTONDOWN) {
                            resetKeyFlags();
                            if (!isEditMode) {
                                // 查询阶段
                                int numX = 150, numY = 95, inputW = 200, inputH = 40;
                                if (isClickArea(numX, numY, inputW, inputH, msg2.x, msg2.y)) {
                                    currentFocus = FOCUS_EDIT_COURSE_NUM;
                                    lastCursorTime = GetTickCount();
                                }
                                else if (isClickArea(150, 180, 100, 40, msg2.x, msg2.y)) {
                                    long num = str2num(inputBuffer);
                                    if (course::isHave(num)) {
                                        targetCourse = course::getCourse(num);
                                        isEditMode = true;
                                        currentFocus = FOCUS_NONE;
                                    }
                                }
                                else if (isClickArea(270, 180, 100, 40, msg2.x, msg2.y)) {
                                    waitInput = false;
                                    currentMenu = 2;
                                    currentFocus = FOCUS_NONE;
                                }
                            }
                            else {
                                // 编辑阶段
                                int nameX = 150, nameY = 155;
                                int creditX = 150, creditY = 215;
                                int teacherX = 150, teacherY = 275;
                                int inputW = 200, inputH = 40;

                                if (isClickArea(nameX, nameY, inputW, inputH, msg2.x, msg2.y)) {
                                    currentFocus = FOCUS_COURSE_NAME;
                                    lastCursorTime = GetTickCount();
                                }
                                else if (isClickArea(creditX, creditY, inputW, inputH, msg2.x, msg2.y)) {
                                    currentFocus = FOCUS_COURSE_CREDIT;
                                    lastCursorTime = GetTickCount();
                                }
                                else if (isClickArea(teacherX, teacherY, inputW, inputH, msg2.x, msg2.y)) {
                                    currentFocus = FOCUS_COURSE_TEACHER;
                                    lastCursorTime = GetTickCount();
                                }
                                else if (isClickArea(150, 350, 100, 40, msg2.x, msg2.y)) {
                                    // 确认修改
                                    int credit = str2num(tempStr2);
                                    course::editCourse(targetCourse->getNumber(), tempStr1, credit, tempStr3);
                                    cleardevice();
                                    outtextxy(50, 420, _T("课程修改成功！"));
                                    FlushBatchDraw();
                                    Sleep(1000);
                                    waitInput = false;
                                    currentMenu = 2;
                                    currentFocus = FOCUS_NONE;
                                }
                                else if (isClickArea(270, 350, 100, 40, msg2.x, msg2.y)) {
                                    waitInput = false;
                                    currentMenu = 2;
                                    currentFocus = FOCUS_NONE;
                                }
                            }
                        }
                    }

                    handleKeyboardInput();
                    updateCursor();
                    Sleep(10);
                }
            }
            // 查看所有课程（核心修复：持续监听返回事件）
            else if (isClickArea(500, 100, 120, 40, msg.x, msg.y)) {
                bool showList = true;
                while (showList) {
                    BeginBatchDraw();
                    cleardevice();
                    settextcolor(COLOR_BLACK);

                    outtextxy(50, 50, _T("所有课程信息"));
                    // 绘制表头
                    int y = 100;
                    settextstyle(16, 0, _T("微软雅黑"));
                    outtextxy(50, y, _T("编号"));
                    outtextxy(150, y, _T("名称"));
                    outtextxy(280, y, _T("学分"));
                    outtextxy(350, y, _T("授课教师"));
                    y += 30;

                    // 绘制课程列表
                    settextstyle(14, 0, _T("微软雅黑"));
                    if (courseList.empty()) {
                        outtextxy(50, y, _T("暂无课程数据！"));
                    }
                    else {
                        for (auto& c : course::getCourseList()) {
                            if (y > WIN_HEIGHT - 80) break; // 防止超出界面

                            TCHAR numBuf[32] = { 0 };
                            MultiByteToWideChar(CP_ACP, 0, num2str(c.getNumber()).c_str(), -1, numBuf, 32);
                            outtextxy(50, y, numBuf);

                            TCHAR nameBuf[64] = { 0 };
                            MultiByteToWideChar(CP_ACP, 0, c.getName().c_str(), -1, nameBuf, 64);
                            outtextxy(150, y, nameBuf);

                            TCHAR creditBuf[32] = { 0 };
                            MultiByteToWideChar(CP_ACP, 0, num2str(c.getCredit()).c_str(), -1, creditBuf, 32);
                            outtextxy(280, y, creditBuf);

                            TCHAR teacherBuf[64] = { 0 };
                            MultiByteToWideChar(CP_ACP, 0, c.getTeacher().c_str(), -1, teacherBuf, 64);
                            outtextxy(350, y, teacherBuf);

                            y += 25;
                        }
                    }

                    // 绘制返回按钮（固定在底部）
                    drawButton(50, WIN_HEIGHT - 60, 80, 30, _T("返回"), RGB(200, 200, 200), COLOR_BLACK);

                    FlushBatchDraw();
                    EndBatchDraw();

                    // 持续监听返回按钮点击
                    if (MouseHit()) {
                        MOUSEMSG msg2 = GetMouseMsg();
                        if (msg2.uMsg == WM_LBUTTONDOWN && isClickArea(50, WIN_HEIGHT - 60, 80, 30, msg2.x, msg2.y)) {
                            showList = false;
                            currentMenu = 2;
                            currentFocus = FOCUS_NONE;
                        }
                    }

                    Sleep(10); // 降低CPU占用
                }
            }
        }
    }

    FlushBatchDraw();
    EndBatchDraw();
    Sleep(10);
}

// 学生管理界面（核心修复：查看所有学生）
void drawStudentMenu() {
    BeginBatchDraw();
    cleardevice();
    setbkcolor(COLOR_BG);

    // 标题与返回按钮
    settextcolor(COLOR_MENU);
    settextstyle(30, 0, _T("微软雅黑"));
    const TCHAR* title = _T("学生信息管理");
    outtextxy(WIN_WIDTH / 2 - textwidth(title) / 2, 30, title);
    drawButton(20, 20, 80, 30, _T("返回"), RGB(200, 200, 200), COLOR_BLACK);

    // 功能按钮
    drawButton(50, 100, 120, 40, _T("添加学生"), COLOR_MENU, COLOR_TEXT);
    drawButton(200, 100, 120, 40, _T("删除学生"), COLOR_MENU, COLOR_TEXT);
    drawButton(350, 100, 120, 40, _T("学生选课"), COLOR_MENU, COLOR_TEXT);
    drawButton(500, 100, 120, 40, _T("查看所有学生"), COLOR_MENU, COLOR_TEXT);

    // 处理鼠标事件
    if (MouseHit()) {
        MOUSEMSG msg = GetMouseMsg();
        if (msg.uMsg == WM_LBUTTONDOWN) {
            resetKeyFlags();
            currentFocus = FOCUS_NONE;
            if (isClickArea(20, 20, 80, 30, msg.x, msg.y)) {
                currentMenu = 1;
                inputBuffer = tempStr1 = tempStr2 = tempStr3 = "";
                return;
            }
            // 添加学生
            else if (isClickArea(50, 100, 120, 40, msg.x, msg.y)) {
                inputBuffer = tempStr1 = tempStr2 = tempStr3 = "";
                bool waitInput = true;
                while (waitInput) {
                    BeginBatchDraw();
                    cleardevice();
                    settextcolor(COLOR_BLACK);

                    int numX = 150, numY = 95;
                    int nameX = 150, nameY = 155;
                    int sexX = 150, sexY = 215;
                    int gradeX = 150, gradeY = 275;
                    int inputW = 200, inputH = 40;

                    outtextxy(50, 50, _T("添加学生"));
                    outtextxy(50, 100, _T("学生学号："));
                    drawInputBox(numX, numY, inputW, inputH, _T("数字学号"), inputBuffer, currentFocus == FOCUS_STU_NUM);

                    outtextxy(50, 160, _T("学生姓名："));
                    drawInputBox(nameX, nameY, inputW, inputH, _T("姓名"), tempStr1, currentFocus == FOCUS_STU_NAME);

                    outtextxy(50, 220, _T("学生性别："));
                    drawInputBox(sexX, sexY, inputW, inputH, _T("男/女"), tempStr2, currentFocus == FOCUS_STU_SEX);

                    outtextxy(50, 280, _T("学生年级："));
                    drawInputBox(gradeX, gradeY, inputW, inputH, _T("如：2023级"), tempStr3, currentFocus == FOCUS_STU_GRADE);

                    drawButton(150, 350, 100, 40, _T("确认添加"), COLOR_MENU, COLOR_TEXT);
                    drawButton(270, 350, 100, 40, _T("取消"), RGB(200, 200, 200), COLOR_BLACK);

                    FlushBatchDraw();
                    EndBatchDraw();

                    if (MouseHit()) {
                        MOUSEMSG msg2 = GetMouseMsg();
                        if (msg2.uMsg == WM_LBUTTONDOWN) {
                            resetKeyFlags();
                            if (isClickArea(numX, numY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_STU_NUM;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(nameX, nameY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_STU_NAME;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(sexX, sexY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_STU_SEX;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(gradeX, gradeY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_STU_GRADE;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(150, 350, 100, 40, msg2.x, msg2.y)) {
                                long num = str2num(inputBuffer);
                                if (!student::isHave(num) && !inputBuffer.empty() && !tempStr1.empty()) {
                                    student::addStudent(num, tempStr1, tempStr2, tempStr3);
                                    cleardevice();
                                    outtextxy(50, 420, _T("学生添加成功！"));
                                }
                                else {
                                    cleardevice();
                                    outtextxy(50, 420, _T("学号重复或信息为空！"));
                                }
                                FlushBatchDraw();
                                Sleep(1000);
                                waitInput = false;
                                currentMenu = 3;
                                currentFocus = FOCUS_NONE;
                            }
                            else if (isClickArea(270, 350, 100, 40, msg2.x, msg2.y)) {
                                waitInput = false;
                                currentMenu = 3;
                                currentFocus = FOCUS_NONE;
                            }
                        }
                    }

                    handleKeyboardInput();
                    updateCursor();
                    Sleep(10);
                }
            }
            // 学生选课
            else if (isClickArea(350, 100, 120, 40, msg.x, msg.y)) {
                inputBuffer = tempStr1 = "";
                bool waitInput = true;
                while (waitInput) {
                    BeginBatchDraw();
                    cleardevice();
                    settextcolor(COLOR_BLACK);

                    int stuX = 150, stuY = 95;
                    int courseX = 150, courseY = 155;
                    int inputW = 200, inputH = 40;

                    outtextxy(50, 50, _T("学生选课"));
                    outtextxy(50, 100, _T("学生学号："));
                    drawInputBox(stuX, stuY, inputW, inputH, _T("输入学号"), inputBuffer, currentFocus == FOCUS_STU_SELECT_STU_NUM);

                    outtextxy(50, 160, _T("课程编号："));
                    drawInputBox(courseX, courseY, inputW, inputH, _T("输入课程编号"), tempStr1, currentFocus == FOCUS_STU_SELECT_COURSE_NUM);

                    drawButton(150, 220, 100, 40, _T("确认选课"), COLOR_MENU, COLOR_TEXT);
                    drawButton(270, 220, 100, 40, _T("取消"), RGB(200, 200, 200), COLOR_BLACK);

                    FlushBatchDraw();
                    EndBatchDraw();

                    if (MouseHit()) {
                        MOUSEMSG msg2 = GetMouseMsg();
                        if (msg2.uMsg == WM_LBUTTONDOWN) {
                            resetKeyFlags();
                            if (isClickArea(stuX, stuY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_STU_SELECT_STU_NUM;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(courseX, courseY, inputW, inputH, msg2.x, msg2.y)) {
                                currentFocus = FOCUS_STU_SELECT_COURSE_NUM;
                                lastCursorTime = GetTickCount();
                            }
                            else if (isClickArea(150, 220, 100, 40, msg2.x, msg2.y)) {
                                long stuNum = str2num(inputBuffer);
                                long courseNum = str2num(tempStr1);
                                if (student::isHave(stuNum) && course::isHave(courseNum)) {
                                    student::addCourseToStudent(stuNum, courseNum);
                                    cleardevice();
                                    outtextxy(50, 290, _T("选课成功！"));
                                }
                                else {
                                    cleardevice();
                                    outtextxy(50, 290, _T("学生或课程不存在！"));
                                }
                                FlushBatchDraw();
                                Sleep(1000);
                                waitInput = false;
                                currentMenu = 3;
                                currentFocus = FOCUS_NONE;
                            }
                            else if (isClickArea(270, 220, 100, 40, msg2.x, msg2.y)) {
                                waitInput = false;
                                currentMenu = 3;
                                currentFocus = FOCUS_NONE;
                            }
                        }
                    }

                    handleKeyboardInput();
                    updateCursor();
                    Sleep(10);
                }
            }
            // 查看所有学生（核心修复：持续监听返回事件）
            else if (isClickArea(500, 100, 120, 40, msg.x, msg.y)) {
                bool showList = true;
                while (showList) {
                    BeginBatchDraw();
                    cleardevice();
                    settextcolor(COLOR_BLACK);

                    outtextxy(50, 50, _T("所有学生信息"));
                    // 绘制表头
                    int y = 100;
                    settextstyle(16, 0, _T("微软雅黑"));
                    outtextxy(50, y, _T("学号"));
                    outtextxy(150, y, _T("姓名"));
                    outtextxy(250, y, _T("性别"));
                    outtextxy(300, y, _T("年级"));
                    outtextxy(400, y, _T("已选课程数"));
                    y += 30;

                    // 绘制学生列表
                    settextstyle(14, 0, _T("微软雅黑"));
                    if (studentList.empty()) {
                        outtextxy(50, y, _T("暂无学生数据！"));
                    }
                    else {
                        for (auto& s : student::getStudentList()) {
                            if (y > WIN_HEIGHT - 80) break; // 防止超出界面

                            TCHAR numBuf[32] = { 0 };
                            MultiByteToWideChar(CP_ACP, 0, num2str(s.getNumber()).c_str(), -1, numBuf, 32);
                            outtextxy(50, y, numBuf);

                            TCHAR nameBuf[64] = { 0 };
                            MultiByteToWideChar(CP_ACP, 0, s.getName().c_str(), -1, nameBuf, 64);
                            outtextxy(150, y, nameBuf);

                            TCHAR sexBuf[32] = { 0 };
                            MultiByteToWideChar(CP_ACP, 0, s.getSex().c_str(), -1, sexBuf, 32);
                            outtextxy(250, y, sexBuf);

                            TCHAR gradeBuf[32] = { 0 };
                            MultiByteToWideChar(CP_ACP, 0, s.getGrade().c_str(), -1, gradeBuf, 32);
                            outtextxy(300, y, gradeBuf);

                            TCHAR courseCntBuf[32] = { 0 };
                            MultiByteToWideChar(CP_ACP, 0, num2str(s.getHaveC().size()).c_str(), -1, courseCntBuf, 32);
                            outtextxy(400, y, courseCntBuf);

                            y += 25;
                        }
                    }

                    // 绘制返回按钮（固定在底部）
                    drawButton(50, WIN_HEIGHT - 60, 80, 30, _T("返回"), RGB(200, 200, 200), COLOR_BLACK);

                    FlushBatchDraw();
                    EndBatchDraw();

                    // 持续监听返回按钮点击
                    if (MouseHit()) {
                        MOUSEMSG msg2 = GetMouseMsg();
                        if (msg2.uMsg == WM_LBUTTONDOWN && isClickArea(50, WIN_HEIGHT - 60, 80, 30, msg2.x, msg2.y)) {
                            showList = false;
                            currentMenu = 3;
                            currentFocus = FOCUS_NONE;
                        }
                    }

                    Sleep(10);
                }
            }
        }
    }

    FlushBatchDraw();
    EndBatchDraw();
    Sleep(10);
}

// 主函数
int main() {
    initgraph(WIN_WIDTH, WIN_HEIGHT);
    setbkcolor(COLOR_BG);
    cleardevice();
    lastCursorTime = GetTickCount();
    resetKeyFlags();

    while (true) {
        updateCursor();
        if (!isLogin) {
            drawLogin();
        }
        else {
            switch (currentMenu) {
            case 1: drawMainMenu(); break;
            case 2: drawCourseMenu(); break;
            case 3: drawStudentMenu(); break;
            default: currentMenu = 1; break;
            }
        }
    }

    closegraph();
    return 0;
}