from flask import Flask, render_template, request, redirect, url_for, flash, send_from_directory, jsonify
import os
from werkzeug.utils import secure_filename
import json
from datetime import datetime

app = Flask(__name__)
app.secret_key = 'your_secret_key_here'

# 配置上传文件夹
UPLOAD_FOLDER = 'uploads'
ALLOWED_EXTENSIONS = {'txt', 'pdf', 'png', 'jpg', 'jpeg', 'gif', 'doc', 'docx', 'zip', 'rar'}

app.config['UPLOAD_FOLDER'] = UPLOAD_FOLDER

# 确保上传目录存在
os.makedirs(UPLOAD_FOLDER, exist_ok=True)

def allowed_file(filename):
    return '.' in filename and \
           filename.rsplit('.', 1)[1].lower() in ALLOWED_EXTENSIONS

def get_file_info(filepath):
    """获取文件信息"""
    stat = os.stat(filepath)
    return {
        'name': os.path.basename(filepath),
        'size': stat.st_size,
        'modified': datetime.fromtimestamp(stat.st_mtime).strftime('%Y-%m-%d %H:%M:%S'),
        'path': filepath
    }

@app.route('/')
def index():
    # 获取所有上传的文件
    files = []
    for filename in os.listdir(app.config['UPLOAD_FOLDER']):
        filepath = os.path.join(app.config['UPLOAD_FOLDER'], filename)
        if os.path.isfile(filepath):
            files.append(get_file_info(filepath))
    
    return render_template('index.html', files=files)

@app.route('/upload', methods=['POST'])
def upload_file():
    if 'file' not in request.files:
        flash('没有选择文件')
        return redirect(request.url)
    
    file = request.files['file']
    
    if file.filename == '':
        flash('没有选择文件')
        return redirect(url_for('index'))
    
    if file and allowed_file(file.filename):
        filename = secure_filename(file.filename)
        file_path = os.path.join(app.config['UPLOAD_FOLDER'], filename)
        
        # 如果文件已存在，则添加时间戳避免覆盖
        if os.path.exists(file_path):
            base, ext = os.path.splitext(filename)
            timestamp = datetime.now().strftime('%Y%m%d_%H%M%S')
            filename = f"{base}_{timestamp}{ext}"
            file_path = os.path.join(app.config['UPLOAD_FOLDER'], filename)
        
        file.save(file_path)
        flash(f'文件 {filename} 上传成功!')
        return redirect(url_for('index'))
    else:
        flash('不支持的文件类型')
        return redirect(url_for('index'))

@app.route('/download/<filename>')
def download_file(filename):
    try:
        return send_from_directory(app.config['UPLOAD_FOLDER'], filename, as_attachment=True)
    except FileNotFoundError:
        flash('文件不存在')
        return redirect(url_for('index'))

@app.route('/delete/<filename>')
def delete_file(filename):
    try:
        file_path = os.path.join(app.config['UPLOAD_FOLDER'], filename)
        os.remove(file_path)
        flash(f'文件 {filename} 删除成功!')
    except FileNotFoundError:
        flash('文件不存在')
    
    return redirect(url_for('index'))

@app.route('/list_files')
def list_files():
    """API接口：返回所有文件列表"""
    files = []
    for filename in os.listdir(app.config['UPLOAD_FOLDER']):
        filepath = os.path.join(app.config['UPLOAD_FOLDER'], filename)
        if os.path.isfile(filepath):
            files.append(get_file_info(filepath))
    
    return jsonify(files)

# 创建一个应用实例供gunicorn使用
application = app

if __name__ == '__main__':
    app.run(debug=True, host='0.0.0.0', port=5000)