#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
优化的Flask应用启动脚本
启用Keep-Alive、缓存和gzip压缩
"""

from app import app
from flask import after_this_request, request
import gzip
from io import BytesIO
import os

# 启用Keep-Alive
class KeepAliveMiddleware:
    def __init__(self, app):
        self.app = app
    
    def __call__(self, environ, start_response):
        def new_start_response(status, response_headers, exc_info=None):
            # 添加Keep-Alive头
            response_headers.append(('Connection', 'keep-alive'))
            response_headers.append(('Keep-Alive', 'timeout=5, max=100'))
            return start_response(status, response_headers, exc_info)
        
        return self.app(environ, new_start_response)

# 启用Gzip压缩
class GzipMiddleware:
    def __init__(self, app, minimum_size=500):
        self.app = app
        self.minimum_size = minimum_size
    
    def __call__(self, environ, start_response):
        def new_start_response(status, response_headers, exc_info=None):
            self.start_response = start_response
            self.response_headers = response_headers
            return start_response(status, response_headers, exc_info)
        
        app_iter = self.app(environ, new_start_response)
        
        try:
            # 检查是否支持gzip
            accept_encoding = environ.get('HTTP_ACCEPT_ENCODING', '')
            if 'gzip' not in accept_encoding:
                return app_iter
            
            # 收集响应数据
            response_data = b''.join(app_iter)
            
            # 只压缩大于minimum_size的响应
            if len(response_data) < self.minimum_size:
                return [response_data]
            
            # 压缩数据
            buffer = BytesIO()
            with gzip.GzipFile(mode='wb', fileobj=buffer) as gz:
                gz.write(response_data)
            gzipped_data = buffer.getvalue()
            
            # 修改响应头
            for header, value in self.response_headers:
                if header.lower() == 'content-length':
                    self.response_headers.remove([header, value])
                    break
            
            self.response_headers.append(('Content-Encoding', 'gzip'))
            self.response_headers.append(('Content-Length', str(len(gzipped_data))))
            
            # 发送响应
            self.start_response(status, self.response_headers, exc_info)
            return [gzipped_data]
            
        except Exception as e:
            # 出错时返回原始响应
            return app_iter

# 添加缓存头
@app.after_request
def add_cache_headers(response):
    # 静态资源缓存1小时
    if request.path.startswith('/assets/') or request.path.startswith('/js/') or request.path.startswith('/css/'):
        response.cache_control.max_age = 3600
        response.headers['Cache-Control'] = 'public, max-age=3600'
    # API不缓存
    elif request.path.startswith('/api/'):
        response.headers['Cache-Control'] = 'no-cache'
    return response

# 应用中间件
app.wsgi_app = KeepAliveMiddleware(app.wsgi_app)
app.wsgi_app = GzipMiddleware(app.wsgi_app)

if __name__ == '__main__':
    print("🚀 启动优化版服务器...")
    print("✅ Keep-Alive: 已启用")
    print("✅ Gzip压缩: 已启用")
    print("✅ 静态资源缓存: 1小时")
    
    # 使用多线程模式
    app.run(
        host='0.0.0.0', 
        port=int(os.environ.get('PORT', '5000')), 
        threaded=True,
        debug=False
    )