class TeacherDashboard {
    constructor() {
        // 动态设置API基础URL，支持file:///协议和localhost:3000访问
        this.apiBase = window.location.protocol === 'file:' ? 'http://localhost:3000/api' : '/api';
        this.currentUser = null;
        this.courses = [];
        this.grades = [];
        this.init();
    }

    async init() {
        // 检查登录状�?        if (!await this.checkAuth()) {
            window.location.href = '/login';
            return;
        }

        // 加载用户信息
        await this.loadUserInfo();
        
        // 加载课程数据
        await this.loadCourses();
        
        // 加载成绩数据
        await this.loadGrades();
        
        // 绑定事件
        this.bindEvents();
        
        // 更新界面
        this.updateUI();
    }

    async checkAuth() {
        try {
            const response = await fetch(`${this.apiBase}/auth/check`, {
                credentials: 'include'
            });
            
            if (!response.ok) {
                return false;
            }
            
            const data = await response.json();
            return data.success && data.user.role === 'teacher';
        } catch (error) {
            console.error('认证检查失�?', error);
            return false;
        }
    }

    async loadUserInfo() {
        try {
            const response = await fetch(`${this.apiBase}/auth/me`, {
                credentials: 'include'
            });
            
            if (response.ok) {
                const data = await response.json();
                if (data.success) {
                    this.currentUser = data.user;
                }
            }
        } catch (error) {
            console.error('加载用户信息失败:', error);
        }
    }

    async loadCourses() {
        try {
            const response = await fetch(`${this.apiBase}/teacher/courses`, {
                credentials: 'include'
            });
            
            if (response.ok) {
                const data = await response.json();
                if (data.success) {
                    this.courses = data.courses;
                    this.populateCourseSelectors();
                }
            }
        } catch (error) {
            console.error('加载课程失败:', error);
            this.showNotification('加载课程失败', 'error');
        }
    }

    async loadGrades(filters = {}) {
        try {
            const queryParams = new URLSearchParams(filters).toString();
            const url = `${this.apiBase}/teacher/grades${queryParams ? '?' + queryParams : ''}`;
            
            const response = await fetch(url, {
                credentials: 'include'
            });
            
            if (response.ok) {
                const data = await response.json();
                if (data.success) {
                    this.grades = data.grades;
                    this.renderGradesTable();
                }
            }
        } catch (error) {
            console.error('加载成绩失败:', error);
            this.showNotification('加载成绩失败', 'error');
        }
    }

    populateCourseSelectors() {
        // 填充课程选择�?        const courseSelectors = document.querySelectorAll('.course-selector');
        courseSelectors.forEach(select => {
            select.innerHTML = '<option value="">请选择课程</option>';
            this.courses.forEach(course => {
                const option = document.createElement('option');
                option.value = course.id;
                option.textContent = `${course.course_code} - ${course.course_name}`;
                select.appendChild(option);
            });
        });
    }

    renderGradesTable() {
        const tableBody = document.getElementById('gradesTableBody');
        if (!tableBody) return;

        if (this.grades.length === 0) {
            tableBody.innerHTML = `
                <tr>
                    <td colspan="9" class="text-center">
                        <div class="no-data">
                            <i class="fas fa-info-circle"></i>
                            <p>暂无成绩数据</p>
                        </div>
                    </td>
                </tr>
            `;
            return;
        }

        tableBody.innerHTML = this.grades.map(grade => {
            const gradeClass = this.getGradeClass(grade.score);
            return `
                <tr>
                    <td><input type="checkbox" class="grade-checkbox" data-id="${grade.id}"></td>
                    <td>${grade.student_id}</td>
                    <td>${grade.full_name}</td>
                    <td>${grade.class_name}</td>
                    <td>${grade.course_code}</td>
                    <td>${grade.course_name}</td>
                    <td class="grade-cell ${gradeClass}">
                        <span class="grade-score">${grade.score}</span>
                        <span class="grade-level">${grade.grade_level}</span>
                    </td>
                    <td>${grade.exam_date ? new Date(grade.exam_date).toLocaleDateString() : '未设�?}</td>
                    <td>
                        <div class="action-buttons">
                            <button class="btn-edit" data-id="${grade.id}">
                                <i class="fas fa-edit"></i> 编辑
                            </button>
                            <button class="btn-delete" data-id="${grade.id}">
                                <i class="fas fa-trash"></i> 删除
                            </button>
                        </div>
                    </td>
                </tr>
            `;
        }).join('');

        // 更新统计信息
        this.updateStats();
    }

    getGradeClass(score) {
        if (score >= 90) return 'grade-excellent';
        if (score >= 80) return 'grade-good';
        if (score >= 70) return 'grade-medium';
        if (score >= 60) return 'grade-pass';
        return 'grade-fail';
    }

    updateStats() {
        if (this.grades.length === 0) return;

        const totalStudents = new Set(this.grades.map(g => g.student_id)).size;
        const avgScore = this.grades.reduce((sum, g) => sum + g.score, 0) / this.grades.length;
        const passRate = (this.grades.filter(g => g.score >= 60).length / this.grades.length * 100).toFixed(1);

        document.getElementById('totalStudents').textContent = totalStudents;
        document.getElementById('avgScore').textContent = avgScore.toFixed(1);
        document.getElementById('passRate').textContent = `${passRate}%`;
    }

    bindEvents() {
        // 搜索按钮
        document.getElementById('searchBtn')?.addEventListener('click', () => {
            this.handleSearch();
        });

        // 重置按钮
        document.getElementById('resetBtn')?.addEventListener('click', () => {
            this.resetFilters();
        });

        // 导出按钮
        document.getElementById('exportBtn')?.addEventListener('click', () => {
            this.exportGrades();
        });

        // 批量删除按钮
        document.getElementById('batchDeleteBtn')?.addEventListener('click', () => {
            this.batchDeleteGrades();
        });

        // 表格操作按钮事件委托
        document.addEventListener('click', (e) => {
            if (e.target.closest('.btn-edit')) {
                const gradeId = e.target.closest('.btn-edit').dataset.id;
                this.editGrade(gradeId);
            }
            
            if (e.target.closest('.btn-delete')) {
                const gradeId = e.target.closest('.btn-delete').dataset.id;
                this.deleteGrade(gradeId);
            }
        });

        // 退出登�?        document.getElementById('logoutBtn')?.addEventListener('click', () => {
            this.handleLogout();
        });
    }

    handleSearch() {
        const className = document.getElementById('classFilter')?.value || '';
        const courseId = document.getElementById('courseFilter')?.value || '';
        
        this.loadGrades({ class_name: className, course_id: courseId });
    }

    resetFilters() {
        document.getElementById('classFilter').value = '';
        document.getElementById('courseFilter').value = '';
        this.loadGrades();
    }

    async exportGrades() {
        try {
            const response = await fetch(`${this.apiBase}/teacher/grades/export`, {
                credentials: 'include'
            });
            
            if (response.ok) {
                const blob = await response.blob();
                const url = window.URL.createObjectURL(blob);
                const a = document.createElement('a');
                a.href = url;
                a.download = `成绩报表_${new Date().toISOString().split('T')[0]}.xlsx`;
                document.body.appendChild(a);
                a.click();
                document.body.removeChild(a);
                window.URL.revokeObjectURL(url);
            }
        } catch (error) {
            console.error('导出失败:', error);
            this.showNotification('导出失败', 'error');
        }
    }

    async batchDeleteGrades() {
        const checkboxes = document.querySelectorAll('.grade-checkbox:checked');
        if (checkboxes.length === 0) {
            this.showNotification('请选择要删除的成绩', 'warning');
            return;
        }

        if (!confirm(`确定要删除选中�?${checkboxes.length} 条成绩记录吗？`)) {
            return;
        }

        const gradeIds = Array.from(checkboxes).map(cb => cb.dataset.id);
        
        try {
            const response = await fetch(`${this.apiBase}/teacher/grades/batch`, {
                method: 'DELETE',
                headers: { 'Content-Type': 'application/json' },
                credentials: 'include',
                body: JSON.stringify({ gradeIds })
            });
            
            const data = await response.json();
            if (data.success) {
                this.showNotification(`成功删除 ${gradeIds.length} 条成绩记录`, 'success');
                await this.loadGrades();
            } else {
                this.showNotification(data.message || '删除失败', 'error');
            }
        } catch (error) {
            console.error('批量删除失败:', error);
            this.showNotification('批量删除失败', 'error');
        }
    }

    async editGrade(gradeId) {
        const grade = this.grades.find(g => g.id == gradeId);
        if (!grade) return;

        // 这里可以打开编辑模态框
        // 暂时使用简单提示框
        const newScore = prompt('请输入新的分�?', grade.score);
        if (newScore === null) return;

        const numericScore = parseFloat(newScore);
        if (isNaN(numericScore) || numericScore < 0 || numericScore > 100) {
            this.showNotification('请输�?-100之间的有效分�?, 'error');
            return;
        }

        try {
            const response = await fetch(`${this.apiBase}/teacher/grades/${gradeId}`, {
                method: 'PUT',
                headers: { 'Content-Type': 'application/json' },
                credentials: 'include',
                body: JSON.stringify({ 
                    score: numericScore,
                    examDate: grade.exam_date,
                    remark: grade.remark
                })
            });
            
            const data = await response.json();
            if (data.success) {
                this.showNotification('成绩更新成功', 'success');
                await this.loadGrades();
            } else {
                this.showNotification(data.message || '更新失败', 'error');
            }
        } catch (error) {
            console.error('更新成绩失败:', error);
            this.showNotification('更新成绩失败', 'error');
        }
    }

    async deleteGrade(gradeId) {
        if (!confirm('确定要删除这条成绩记录吗�?)) {
            return;
        }

        try {
            const response = await fetch(`${this.apiBase}/teacher/grades/${gradeId}`, {
                method: 'DELETE',
                credentials: 'include'
            });
            
            const data = await response.json();
            if (data.success) {
                this.showNotification('成绩删除成功', 'success');
                await this.loadGrades();
            } else {
                this.showNotification(data.message || '删除失败', 'error');
            }
        } catch (error) {
            console.error('删除成绩失败:', error);
            this.showNotification('删除成绩失败', 'error');
        }
    }

    async handleLogout() {
        try {
            const response = await fetch(`${this.apiBase}/auth/logout`, {
                method: 'POST',
                credentials: 'include'
            });
            
            if (response.ok) {
                window.location.href = '/login';
            }
        } catch (error) {
            console.error('退出登录失�?', error);
        }
    }

    updateUI() {
        // 更新用户信息
        if (this.currentUser) {
            const userInfoElements = document.querySelectorAll('.user-info');
            userInfoElements.forEach(el => {
                el.textContent = `${this.currentUser.full_name} (${this.currentUser.role})`;
            });
        }
    }

    showNotification(message, type = 'info') {
        // 使用AuthManager的通知系统或简单alert
        if (typeof AuthManager !== 'undefined' && AuthManager.showNotification) {
            AuthManager.showNotification(message, type);
        } else {
            alert(`${type}: ${message}`);
        }
    }
}

// 页面加载完成后初始化
document.addEventListener('DOMContentLoaded', () => {
    if (window.location.pathname.includes('/teacher/')) {
        new TeacherDashboard();
    }
});