from flask import Flask, request, jsonify, send_from_directory
import pandas as pd
import random
from flask_sqlalchemy import SQLAlchemy
from flask_cors import CORS

app = Flask(__name__)
CORS(app)  # 启用 CORS
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///students.db'
app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False
app.config['MAX_CONTENT_LENGTH'] = 16 * 1024 * 1024  # 最大上传文件限制
db = SQLAlchemy(app)

class Student(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(100), nullable=False)
    student_id = db.Column(db.String(20), unique=True, nullable=False)
    points = db.Column(db.Float, default=0)
    called_count = db.Column(db.Integer, default=0)

@app.route('/upload_students', methods=['POST'])
def upload_students():
    if 'file' not in request.files:
        return jsonify(message="未找到文件"), 400

    file = request.files['file']

    if file.filename == '':
        return jsonify(message="没有选择文件"), 400

    if not (file.filename.endswith('.xlsx') or file.filename.endswith('.xls')):
        return jsonify(message="文件格式不支持，请上传 Excel 文件"), 400

    try:
        df = pd.read_excel(file)

        if '姓名' not in df.columns or '学号' not in df.columns:
            return jsonify(message="Excel 文件必须包含 '姓名' 和 '学号' 列"), 400

        for _, row in df.iterrows():
            student = Student(name=row['姓名'], student_id=row['学号'])
            db.session.add(student)
        db.session.commit()
        return jsonify(message="学生名单上传成功"), 200

    except Exception as e:
        print(f"Error: {e}")
        return jsonify(message=f"文件处理失败: {str(e)}"), 500

@app.route('/call_student', methods=['POST'])
def call_student():
    students = Student.query.all()
    total_points = sum(student.points for student in students)

    if total_points == 0:
        chosen_student = random.choice(students)
    else:
        probabilities = [(student, 1 - (student.points / total_points)) for student in students]
        total_prob = sum(prob[1] for prob in probabilities)
        chosen_student = random.choices(
            [prob[0] for prob in probabilities],
            weights=[prob[1] / total_prob for prob in probabilities]
        )[0]

    chosen_student.called_count += 1
    chosen_student.points += 1  # 点到后增加积分
    db.session.commit()

    return jsonify(name=chosen_student.name, student_id=chosen_student.student_id, index=chosen_student.id)

@app.route('/update_points', methods=['POST'])
def update_points():
    data = request.json
    student = Student.query.get(data['index'])
    answer = data['answer']

    score = 0
    question = "1+1=？"  # 假设提问内容

    if answer == question:
        score += 0.5
        result_message = "回答正确！"
    else:
        score -= 1
        result_message = "回答错误！"

    # 模拟准确回答的情况
    if "Ezio" == answer:
        score += random.uniform(0.5, 3.0)
        result_message = "回答非常正确！"

    student.points += score
    db.session.commit()

    if student.points < 0:
        student.points = 0  # 确保积分不为负值
    db.session.commit()

    return jsonify(points=student.points, message=result_message)

@app.route('/')
def index():
    return send_from_directory('', 'index.html')

if __name__ == '__main__':
    with app.app_context():
        db.create_all()
    app.run(debug=True)