# 学生管理API接口
from flask import jsonify, request, session
import hashlib
import uuid
import time
import json
import os

# 学生数据文件路径
STUDENTS_FILE = 'students.json'

def hash_password(password):
    """密码加密"""
    return hashlib.sha256(password.encode()).hexdigest()

def load_students():
    """加载学生数据"""
    if os.path.exists(STUDENTS_FILE):
        with open(STUDENTS_FILE, 'r', encoding='utf-8') as f:
            return json.load(f)
    return []

def save_students(students):
    """保存学生数据"""
    with open(STUDENTS_FILE, 'w', encoding='utf-8') as f:
        json.dump(students, f, ensure_ascii=False, indent=2)

def register_student_routes(app):
    """注册学生管理相关的路由"""

    @app.route('/api/teacher/students', methods=['GET'])
    def get_students():
        """获取学生列表"""
        if not session.get('logged_in') or session.get('user_type') != 'teacher':
            return jsonify({'success': False, 'message': '需要教师权限'}), 403

        students = load_students()
        # 隐藏密码字段
        safe_students = []
        for student in students:
            safe_student = {k: v for k, v in student.items() if k != 'password'}
            safe_students.append(safe_student)

        return jsonify({
            'success': True,
            'students': safe_students
        })

    @app.route('/api/teacher/students', methods=['POST'])
    def create_student():
        """创建学生账号"""
        if not session.get('logged_in') or session.get('user_type') != 'teacher':
            return jsonify({'success': False, 'message': '需要教师权限'}), 403

        data = request.json
        username = data.get('username')
        password = data.get('password')
        name = data.get('name')

        if not username or not password:
            return jsonify({'success': False, 'message': '用户名和密码不能为空'}), 400

        students = load_students()

        # 检查用户名是否已存在
        if any(s['username'] == username for s in students):
            return jsonify({'success': False, 'message': '用户名已存在'}), 400

        # 创建新学生
        new_student = {
            'id': str(uuid.uuid4()),
            'username': username,
            'password': hash_password(password),
            'name': name,
            'student_id': data.get('student_id'),
            'email': data.get('email'),
            'class': data.get('class'),
            'created_at': time.strftime('%Y-%m-%d %H:%M:%S'),
            'created_by': session.get('username'),
            'total_interactions': 0,
            'last_active': None
        }

        students.append(new_student)
        save_students(students)

        # 返回时不包含密码
        safe_student = {k: v for k, v in new_student.items() if k != 'password'}

        return jsonify({
            'success': True,
            'message': '学生账号创建成功',
            'student': safe_student
        })

    @app.route('/api/teacher/students/<student_id>', methods=['PUT'])
    def update_student(student_id):
        """更新学生信息"""
        if not session.get('logged_in') or session.get('user_type') != 'teacher':
            return jsonify({'success': False, 'message': '需要教师权限'}), 403

        data = request.json
        students = load_students()

        student = next((s for s in students if s['id'] == student_id), None)
        if not student:
            return jsonify({'success': False, 'message': '学生不存在'}), 404

        # 更新字段
        if 'name' in data:
            student['name'] = data['name']
        if 'student_id' in data:
            student['student_id'] = data['student_id']
        if 'email' in data:
            student['email'] = data['email']
        if 'class' in data:
            student['class'] = data['class']
        if 'password' in data and data['password']:
            student['password'] = hash_password(data['password'])

        save_students(students)

        # 返回时不包含密码
        safe_student = {k: v for k, v in student.items() if k != 'password'}

        return jsonify({
            'success': True,
            'message': '学生信息已更新',
            'student': safe_student
        })

    @app.route('/api/teacher/students/<student_id>', methods=['DELETE'])
    def delete_student(student_id):
        """删除学生"""
        if not session.get('logged_in') or session.get('user_type') != 'teacher':
            return jsonify({'success': False, 'message': '需要教师权限'}), 403

        students = load_students()
        students = [s for s in students if s['id'] != student_id]
        save_students(students)

        return jsonify({
            'success': True,
            'message': '学生已删除'
        })

    @app.route('/api/teacher/students/<student_id>/reset-password', methods=['POST'])
    def reset_student_password(student_id):
        """重置学生密码"""
        if not session.get('logged_in') or session.get('user_type') != 'teacher':
            return jsonify({'success': False, 'message': '需要教师权限'}), 403

        students = load_students()
        student = next((s for s in students if s['id'] == student_id), None)

        if not student:
            return jsonify({'success': False, 'message': '学生不存在'}), 404

        # 生成新的随机密码
        new_password = str(uuid.uuid4())[:8]
        student['password'] = hash_password(new_password)
        save_students(students)

        return jsonify({
            'success': True,
            'message': '密码已重置',
            'newPassword': new_password
        })

    @app.route('/api/teacher/students/<student_id>/progress', methods=['GET'])
    def get_student_progress(student_id):
        """获取学生学习进度"""
        if not session.get('logged_in') or session.get('user_type') != 'teacher':
            return jsonify({'success': False, 'message': '需要教师权限'}), 403

        # 获取学生的活动记录
        from app import student_activities

        students = load_students()
        student = next((s for s in students if s['id'] == student_id), None)

        if not student:
            return jsonify({'success': False, 'message': '学生不存在'}), 404

        # 获取该学生的活动
        username = student['username']
        activities = student_activities.get(username, [])

        # 统计常用Agent
        agent_usage = {}
        for activity in activities:
            agent_name = activity.get('agent_name')
            if agent_name:
                agent_usage[agent_name] = agent_usage.get(agent_name, 0) + 1

        frequently_used_agents = sorted(agent_usage.keys(),
                                       key=lambda x: agent_usage[x],
                                       reverse=True)[:3]

        # 获取最近活动
        recent_activities = activities[-10:][::-1]  # 最近10条，倒序

        return jsonify({
            'success': True,
            'progress': {
                'total_interactions': student.get('total_interactions', 0),
                'last_active': student.get('last_active'),
                'frequently_used_agents': frequently_used_agents,
                'recent_activities': [
                    {
                        'title': a['title'],
                        'time': time.strftime('%Y-%m-%d %H:%M',
                                             time.localtime(a['timestamp']))
                    }
                    for a in recent_activities
                ]
            }
        })