import io
from flask import Flask, request, jsonify, render_template, send_file
import pandas as pd
import os
import random
from flask_cors import CORS

app = Flask(__name__)
CORS(app)

# 学生类，包含姓名、学号和积分
class Student:
    def __init__(self, id, name, score=0.0):
        self.id = id
        self.name = name
        self.score = score

# 从Excel文件中读取学生名单
def Original_Reading(file):
    df = pd.read_excel(file)

    # 检查是否存在“积分”列，如果不存在则初始化一个积分列并设置为0
    if '积分' not in df.columns:
        df['积分'] = 0.0

    students = []
    for i, row in df.iterrows():
        students.append(Student(row['学号'], row['姓名'], row['积分']))
    return students

# 从排行榜文件中读取学生名单
def Leaderboard_Reading(file):
    if not os.path.exists(file):
        return None
    df = pd.read_excel(file)
    s = []
    for i, row in df.iterrows():
        s.append(Student(row['学号'], row['姓名'], row['积分']))
    return s

# 随机选择一个学生
def Select_Student(students):
    total = sum(s.score for s in students)
    if total == 0:
        # 如果总积分为零，所有学生的权重都为1
        w = [1] * len(students)
    else:
        w = [(total - student.score + 1) for student in students]
    selected_student = random.choices(students, weights=w, k=1)[0]
    return selected_student

# 更新学生的积分
def update_score(s, arrived, repeated, correct):
    if arrived == 1:
        s.score += 1.0
    if repeated == 1:
        s.score += 0.5
    elif repeated == 2:
        s.score -= 1.0
    if correct:
        s.score += correct


# 将学生列表转换为DataFrame并按积分从大到小排序
def students_to_dataframe(students):
    total = sum(s.score for s in students)
    if total == 0:
        # 如果总积分为零，所有学生的权重都为1
        weights = [1] * len(students)
    else:
        weights = [(total - s.score + 1) for s in students]

    total_weight = sum(weights)
    pro = [weight / total_weight * 100 for weight in weights]

    data = {'学号': [s.id for s in students],
            '姓名': [s.name for s in students],
            '积分': [s.score for s in students],
            '抽取概率(%)': pro}
    df = pd.DataFrame(data)
    df = df.sort_values(by='积分', ascending=False).reset_index(drop=True)
    return df

# 主程序
students = []

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

@app.route('/upload', methods=['POST'])
def upload_file():
    global students
    file = request.files['file']
    if file and file.filename.endswith('.xlsx'):
        students = Original_Reading(file)
        return jsonify({'success': True})
    return jsonify({'success': False})

@app.route('/select_student', methods=['GET'])
def select_student():
    global students
    if not students:
        return jsonify({'error': 'No students available'})
    selected_student = Select_Student(students)
    return jsonify({'name': selected_student.name, 'id': selected_student.id, 'score': selected_student.score})

@app.route('/update_score', methods=['POST'])
def update_student_score():
    global students
    data = request.json
    student_id = data.get('id')
    arrived = data.get('arrived')
    repeated = data.get('repeated')
    correct = data.get('correct')

    student = next((s for s in students if s.id == student_id), None)
    if student:
        update_score(student, arrived, repeated, correct)
        return jsonify({'success': True, 'score': student.score})
    return jsonify({'success': False, 'error': '未找到该学生'})

@app.route('/export_file', methods=['GET'])
def export_file():
    global students
    if not students:
        return jsonify({'error': 'No students available'})

    df = students_to_dataframe(students)
    output = io.BytesIO()
    with pd.ExcelWriter(output, engine='xlsxwriter') as writer:
        df.to_excel(writer, sheet_name='students', index=False)
    output.seek(0)
    return send_file(output, download_name='students.xlsx', as_attachment=True)

@app.route('/check_probability', methods=['GET'])
def check_probability():
    global students
    student_id = request.args.get('id')
    student = next((s for s in students if s.id == student_id), None)
    if student:
        total = sum(s.score for s in students)
        if total == 0:
            probability = 1 / len(students)
        else:
            probability = (total - student.score + 1) / total
        return jsonify({'probability': probability})
    return jsonify({'error': 'Student not found'})

@app.route('/select_ten_students', methods=['GET'])
def select_ten_students():
    global students
    if not students:
        return jsonify({'error': 'No students available'})

    selected_students = []
    for _ in range(10):
        selected_student = Select_Student(students)
        selected_students.append({
            'name': selected_student.name,
            'id': selected_student.id,
            'score': selected_student.score
        })

    return jsonify({'students': selected_students})


if __name__ == '__main__':
    app.run(debug=True)