"""
AI助手Web客户端 - Flask应用
对接im-api后端聊天服务
@author huazm
"""

import os
import sys
import json
import logging
import requests
from flask import Flask, render_template, request, jsonify, Response, stream_with_context
from flask_cors import CORS

# 配置日志
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s'
)
logger = logging.getLogger(__name__)

# 创建Flask应用
app = Flask(__name__)
app.config['SECRET_KEY'] = 'ai-assistant-web-client-secret-key'
CORS(app)  # 启用CORS

# API后端地址配置（api模块提供HTTP接口）
API_BASE_URL = os.environ.get('API_BASE_URL', 'http://localhost:18090')
# api模块的接口路径前缀是/api/ai-assistant
API_PREFIX = '/api/ai-assistant'

# 认证token（实际使用时应该从登录获取）
# 这里暂时使用环境变量或固定值
AUTH_TOKEN = os.environ.get('AUTH_TOKEN', '')


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


def get_auth_headers():
    """
    获取认证请求头
    从前端请求中获取Authorization头并传递给后端
    """
    headers = {
        'Content-Type': 'application/json'
    }

    # 优先使用前端传递的Authorization头
    auth_header = request.headers.get('Authorization')
    if auth_header:
        headers['Authorization'] = auth_header
    elif AUTH_TOKEN:
        # 如果前端没有传递，使用环境变量中的token
        headers['Authorization'] = f'Bearer {AUTH_TOKEN}'

    return headers


@app.route('/api/ai-assistant/chatapp', methods=['GET'])
def get_applications():
    """
    代理获取应用列表请求到api后端
    """
    try:
        url = f'{API_BASE_URL}{API_PREFIX}/chatapp'
        logger.info(f"代理请求: GET {url}")

        response = requests.get(
            url,
            headers=get_auth_headers(),
            timeout=30
        )

        logger.info(f"响应状态码: {response.status_code}")

        # 直接返回后端响应
        return Response(
            response.content,
            status=response.status_code,
            content_type=response.headers.get('Content-Type', 'application/json')
        )

    except requests.exceptions.RequestException as e:
        logger.error(f"代理请求失败: {e}")
        return jsonify({
            'code': 500,
            'message': f'代理请求失败: {str(e)}',
            'data': None
        }), 500
    except Exception as e:
        logger.error(f"获取应用列表失败: {e}")
        return jsonify({
            'code': 500,
            'message': str(e),
            'data': None
        }), 500


@app.route('/api/ai-assistant/chatapp/<app_id>/getRecommendQuestion', methods=['GET'])
def get_recommend_questions(app_id):
    """
    代理获取推荐问题请求到api后端
    """
    try:
        # 获取查询参数
        page_size = request.args.get('pageSize', '10')
        current = request.args.get('current', '1')

        url = f'{API_BASE_URL}{API_PREFIX}/chatapp/{app_id}/getRecommendQuestion'
        params = {
            'pageSize': page_size,
            'current': current
        }

        logger.info(f"代理请求: GET {url} with params {params}")

        response = requests.get(
            url,
            params=params,
            headers=get_auth_headers(),
            timeout=30
        )

        return Response(
            response.content,
            status=response.status_code,
            content_type=response.headers.get('Content-Type', 'application/json')
        )

    except Exception as e:
        logger.error(f"获取推荐问题失败: {e}")
        return jsonify({
            'code': 500,
            'message': str(e),
            'data': None
        }), 500


@app.route('/api/ai-assistant/chat/completions/message', methods=['POST'])
def send_message():
    """
    代理发送消息请求到api后端（SSE流式响应）
    """
    try:
        data = request.get_json()

        url = f'{API_BASE_URL}{API_PREFIX}/chat/completions/message'
        logger.info(f"代理SSE请求: POST {url}")
        logger.info(f"请求体: {json.dumps(data, ensure_ascii=False)}")

        # 发送POST请求并流式读取响应
        response = requests.post(
            url,
            json=data,
            headers=get_auth_headers(),
            stream=True,
            timeout=300  # 5分钟超时
        )

        # 流式转发SSE响应
        def generate():
            try:
                for line in response.iter_lines():
                    if line:
                        decoded_line = line.decode('utf-8')
                        logger.debug(f"SSE数据: {decoded_line}")
                        yield f"{decoded_line}\n"
            except Exception as e:
                logger.error(f"流式响应错误: {e}")
                yield f"event: error\ndata: {json.dumps({'error': str(e)})}\n\n"

        return Response(
            stream_with_context(generate()),
            mimetype='text/event-stream',
            headers={
                'Cache-Control': 'no-cache',
                'X-Accel-Buffering': 'no'
            }
        )

    except Exception as e:
        logger.error(f"发送消息失败: {e}")
        return jsonify({
            'code': 500,
            'message': str(e),
            'data': None
        }), 500


@app.route('/api/health', methods=['GET'])
def health_check():
    """
    健康检查
    """
    # 检查api后端是否可用
    api_available = False
    try:
        response = requests.get(
            f'{API_BASE_URL}/actuator/health',
            timeout=5
        )
        api_available = response.status_code == 200
    except:
        pass

    return jsonify({
        'code': 200,
        'message': 'OK',
        'data': {
            'status': 'healthy',
            'api_available': api_available,
            'api_url': API_BASE_URL
        }
    })


if __name__ == '__main__':
    port = int(os.environ.get('PORT', 15000))
    debug = os.environ.get('DEBUG', 'True').lower() == 'true'
    
    logger.info(f"启动AI助手Web客户端，端口: {port}, 调试模式: {debug}")
    app.run(host='0.0.0.0', port=port, debug=debug)