#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
平衡体态检测系统 - 后端服务
基于Flask的本地API服务
"""

import os
import sys
import json
import time
import threading
from datetime import datetime
from flask import Flask, request, jsonify, send_file
from flask_cors import CORS
import sqlite3
import logging
from pathlib import Path

# 添加当前目录到Python路径
sys.path.append(os.path.dirname(os.path.abspath(__file__)))

# 导入自定义模块
from database import DatabaseManager
from device_manager import DeviceManager
from detection_engine import DetectionEngine
from data_processor import DataProcessor

# 配置日志
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
    handlers=[
        logging.FileHandler('logs/backend.log', encoding='utf-8'),
        logging.StreamHandler()
    ]
)
logger = logging.getLogger(__name__)

# 创建Flask应用
app = Flask(__name__)
app.config['SECRET_KEY'] = 'body-balance-detection-system-2024'

# 启用CORS支持
CORS(app, origins=['http://localhost:3000', 'http://localhost:3001', 'file://*'])

# 全局变量
db_manager = None
device_manager = None
detection_engine = None
data_processor = None
current_detection = None
detection_thread = None

def init_app():
    """初始化应用"""
    global db_manager, device_manager, detection_engine, data_processor
    
    try:
        # 创建必要的目录
        os.makedirs('logs', exist_ok=True)
        os.makedirs('data', exist_ok=True)
        os.makedirs('exports', exist_ok=True)
        os.makedirs('videos', exist_ok=True)
        
        # 初始化数据库
        db_manager = DatabaseManager('data/body_balance.db')
        db_manager.init_database()
        
        # 初始化设备管理器
        device_manager = DeviceManager()
        
        # 初始化检测引擎
        detection_engine = DetectionEngine()
        
        # 初始化数据处理器
        data_processor = DataProcessor()
        
        logger.info('应用初始化完成')
        
    except Exception as e:
        logger.error(f'应用初始化失败: {e}')
        raise

# ==================== 基础API ====================

@app.route('/health', methods=['GET'])
def health_check():
    """健康检查"""
    return jsonify({
        'status': 'ok',
        'timestamp': datetime.now().isoformat(),
        'version': '1.0.0'
    })

@app.route('/api/health', methods=['GET'])
def api_health_check():
    """API健康检查"""
    return jsonify({
        'status': 'ok',
        'timestamp': datetime.now().isoformat(),
        'version': '1.0.0'
    })

# ==================== 认证API ====================

@app.route('/api/auth/login', methods=['POST'])
def login():
    """用户登录"""
    try:
        data = request.get_json()
        username = data.get('username')
        password = data.get('password')
        remember = data.get('remember', False)
        
        # 简单的模拟登录验证
        if username and password:
            # 这里可以添加真实的用户验证逻辑
            # 目前使用模拟数据
            user_data = {
                'id': 1,
                'username': username,
                'name': '医生',
                'role': 'doctor',
                'avatar': ''
            }
            
            # 生成简单的token（实际项目中应使用JWT等安全token）
            token = f"token_{username}_{int(time.time())}"
            
            return jsonify({
                'success': True,
                'data': {
                    'token': token,
                    'user': user_data
                },
                'message': '登录成功'
            })
        else:
            return jsonify({
                'success': False,
                'message': '用户名或密码不能为空'
            }), 400
            
    except Exception as e:
        logger.error(f'登录失败: {e}')
        return jsonify({'success': False, 'message': '登录失败'}), 500

@app.route('/api/auth/register', methods=['POST'])
def register():
    """用户注册"""
    try:
        data = request.get_json()
        username = data.get('username')
        password = data.get('password')
        email = data.get('email')
        
        # 简单的模拟注册
        if username and password:
            return jsonify({
                'success': True,
                'message': '注册成功，请登录'
            })
        else:
            return jsonify({
                'success': False,
                'message': '用户名和密码不能为空'
            }), 400
            
    except Exception as e:
        logger.error(f'注册失败: {e}')
        return jsonify({'success': False, 'message': '注册失败'}), 500

@app.route('/api/auth/logout', methods=['POST'])
def logout():
    """用户退出"""
    try:
        return jsonify({
            'success': True,
            'message': '退出成功'
        })
    except Exception as e:
        logger.error(f'退出失败: {e}')
        return jsonify({'success': False, 'message': '退出失败'}), 500

@app.route('/api/auth/verify', methods=['GET'])
def verify_token():
    """验证token"""
    try:
        # 简单的token验证（实际项目中应验证JWT等）
        auth_header = request.headers.get('Authorization')
        if auth_header and auth_header.startswith('Bearer '):
            token = auth_header.split(' ')[1]
            # 这里可以添加真实的token验证逻辑
            return jsonify({
                'success': True,
                'data': {'valid': True}
            })
        else:
            return jsonify({
                'success': True,
                'data': {'valid': True}  # 暂时总是返回有效
            })
    except Exception as e:
        logger.error(f'验证token失败: {e}')
        return jsonify({'success': False, 'message': '验证失败'}), 500

@app.route('/api/auth/forgot-password', methods=['POST'])
def forgot_password():
    """忘记密码"""
    try:
        data = request.get_json()
        email = data.get('email')
        
        if email:
            return jsonify({
                'success': True,
                'message': '重置密码邮件已发送'
            })
        else:
            return jsonify({
                'success': False,
                'message': '邮箱不能为空'
            }), 400
            
    except Exception as e:
        logger.error(f'忘记密码处理失败: {e}')
        return jsonify({'success': False, 'message': '处理失败'}), 500

@app.route('/api/auth/reset-password', methods=['POST'])
def reset_password():
    """重置密码"""
    try:
        data = request.get_json()
        token = data.get('token')
        password = data.get('password')
        
        if token and password:
            return jsonify({
                'success': True,
                'message': '密码重置成功'
            })
        else:
            return jsonify({
                'success': False,
                'message': '参数不完整'
            }), 400
            
    except Exception as e:
        logger.error(f'重置密码失败: {e}')
        return jsonify({'success': False, 'message': '重置失败'}), 500

@app.route('/api/system/info', methods=['GET'])
def get_system_info():
    """获取系统信息"""
    try:
        info = {
            'version': '1.0.0',
            'start_time': datetime.now().isoformat(),
            'database_status': 'connected' if db_manager else 'disconnected',
            'device_count': len(device_manager.get_connected_devices()) if device_manager else 0
        }
        return jsonify({'success': True, 'data': info})
    except Exception as e:
        logger.error(f'获取系统信息失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

# ==================== 设备管理API ====================

@app.route('/api/devices/status', methods=['GET'])
def get_device_status():
    """获取设备状态"""
    try:
        if not device_manager:
            return jsonify({'camera': False, 'imu': False, 'pressure': False})
        
        status = device_manager.get_device_status()
        return jsonify(status)
    except Exception as e:
        logger.error(f'获取设备状态失败: {e}')
        return jsonify({'camera': False, 'imu': False, 'pressure': False})

@app.route('/api/devices/refresh', methods=['POST'])
def refresh_devices():
    """刷新设备连接"""
    try:
        if device_manager:
            device_manager.refresh_devices()
        return jsonify({'success': True, 'message': '设备已刷新'})
    except Exception as e:
        logger.error(f'刷新设备失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

@app.route('/api/devices/calibrate', methods=['POST'])
def calibrate_devices():
    """校准设备"""
    try:
        if device_manager:
            result = device_manager.calibrate_devices()
            return jsonify({'success': True, 'data': result})
        return jsonify({'success': False, 'error': '设备管理器未初始化'}), 500
    except Exception as e:
        logger.error(f'设备校准失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

# ==================== 患者管理API ====================

@app.route('/api/patients', methods=['GET'])
def get_patients():
    """获取患者列表"""
    try:
        page = int(request.args.get('page', 1))
        size = int(request.args.get('size', 10))
        keyword = request.args.get('keyword', '')
        
        patients = db_manager.get_patients(page, size, keyword)
        total = db_manager.get_patients_count(keyword)
        
        return jsonify({
            'success': True,
            'data': {
                'patients': patients,
                'total': total,
                'page': page,
                'size': size
            }
        })
    except Exception as e:
        logger.error(f'获取患者列表失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

@app.route('/api/patients', methods=['POST'])
def create_patient():
    """创建患者"""
    try:
        data = request.get_json()
        patient_id = db_manager.create_patient(data)
        return jsonify({
            'success': True,
            'data': {'patient_id': patient_id},
            'message': '患者创建成功'
        })
    except Exception as e:
        logger.error(f'创建患者失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

@app.route('/api/patients/<patient_id>', methods=['PUT'])
def update_patient(patient_id):
    """更新患者信息"""
    try:
        data = request.get_json()
        db_manager.update_patient(patient_id, data)
        return jsonify({'success': True, 'message': '患者信息更新成功'})
    except Exception as e:
        logger.error(f'更新患者信息失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

@app.route('/api/patients/<patient_id>', methods=['DELETE'])
def delete_patient(patient_id):
    """删除患者"""
    try:
        db_manager.delete_patient(patient_id)
        return jsonify({'success': True, 'message': '患者删除成功'})
    except Exception as e:
        logger.error(f'删除患者失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

# ==================== 检测管理API ====================

@app.route('/api/detection/start', methods=['POST'])
def start_detection():
    """开始检测"""
    global current_detection, detection_thread
    
    try:
        if current_detection and current_detection.get('status') == 'running':
            return jsonify({'success': False, 'error': '检测已在进行中'}), 400
        
        data = request.get_json()
        patient_id = data.get('patientId')
        settings = data.get('settings', {})
        
        # 创建检测会话
        session_id = db_manager.create_detection_session(patient_id, settings)
        
        # 初始化检测状态
        current_detection = {
            'session_id': session_id,
            'patient_id': patient_id,
            'status': 'running',
            'start_time': datetime.now(),
            'settings': settings,
            'data_points': 0
        }
        
        # 启动检测线程
        detection_thread = threading.Thread(
            target=run_detection,
            args=(session_id, settings)
        )
        detection_thread.start()
        
        return jsonify({
            'success': True,
            'data': {'session_id': session_id},
            'message': '检测已开始'
        })
        
    except Exception as e:
        logger.error(f'开始检测失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

@app.route('/api/detection/stop', methods=['POST'])
def stop_detection():
    """停止检测"""
    global current_detection
    
    try:
        if not current_detection or current_detection.get('status') != 'running':
            return jsonify({'success': False, 'error': '没有正在进行的检测'}), 400
        
        # 更新检测状态
        current_detection['status'] = 'stopped'
        current_detection['end_time'] = datetime.now()
        
        # 等待检测线程结束
        if detection_thread and detection_thread.is_alive():
            detection_thread.join(timeout=5)
        
        return jsonify({'success': True, 'message': '检测已停止'})
        
    except Exception as e:
        logger.error(f'停止检测失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

@app.route('/api/detection/status', methods=['GET'])
def get_detection_status():
    """获取检测状态"""
    try:
        if not current_detection:
            return jsonify({
                'success': True,
                'data': {'status': 'idle'}
            })
        
        # 计算运行时间
        if current_detection.get('status') == 'running':
            elapsed = (datetime.now() - current_detection['start_time']).total_seconds()
            current_detection['elapsed_time'] = int(elapsed)
        
        return jsonify({
            'success': True,
            'data': current_detection
        })
        
    except Exception as e:
        logger.error(f'获取检测状态失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

@app.route('/api/detection/data', methods=['GET'])
def get_realtime_data():
    """获取实时检测数据"""
    try:
        if not current_detection or current_detection.get('status') != 'running':
            return jsonify({'success': False, 'error': '没有正在进行的检测'})
        
        # 获取最新的检测数据
        session_id = current_detection['session_id']
        data = detection_engine.get_latest_data(session_id)
        
        return jsonify({
            'success': True,
            'data': data
        })
        
    except Exception as e:
        logger.error(f'获取实时数据失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

# ==================== 数据分析API ====================

@app.route('/api/analysis/session/<session_id>', methods=['GET'])
def analyze_session(session_id):
    """分析检测会话数据"""
    try:
        # 获取会话数据
        session_data = db_manager.get_session_data(session_id)
        if not session_data:
            return jsonify({'success': False, 'error': '会话不存在'}), 404
        
        # 进行数据分析
        analysis_result = data_processor.analyze_session(session_data)
        
        # 保存分析结果
        db_manager.save_analysis_result(session_id, analysis_result)
        
        return jsonify({
            'success': True,
            'data': analysis_result
        })
        
    except Exception as e:
        logger.error(f'分析会话数据失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

@app.route('/api/export/report/<session_id>', methods=['GET'])
def export_report(session_id):
    """导出检测报告"""
    try:
        # 生成报告
        report_path = data_processor.generate_report(session_id)
        
        if not os.path.exists(report_path):
            return jsonify({'success': False, 'error': '报告生成失败'}), 500
        
        return send_file(
            report_path,
            as_attachment=True,
            download_name=f'detection_report_{session_id}.pdf'
        )
        
    except Exception as e:
        logger.error(f'导出报告失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

# ==================== 历史记录API ====================

@app.route('/api/history/sessions', methods=['GET'])
def get_detection_sessions():
    """获取检测会话历史"""
    try:
        page = int(request.args.get('page', 1))
        size = int(request.args.get('size', 10))
        patient_id = request.args.get('patient_id')
        
        sessions = db_manager.get_detection_sessions(page, size, patient_id)
        total = db_manager.get_sessions_count(patient_id)
        
        return jsonify({
            'success': True,
            'data': {
                'sessions': sessions,
                'total': total,
                'page': page,
                'size': size
            }
        })
        
    except Exception as e:
        logger.error(f'获取检测历史失败: {e}')
        return jsonify({'success': False, 'error': str(e)}), 500

def run_detection(session_id, settings):
    """运行检测的后台线程"""
    global current_detection
    
    try:
        logger.info(f'开始检测会话: {session_id}')
        
        # 检测循环
        while (current_detection and 
               current_detection.get('status') == 'running'):
            
            # 采集数据
            if device_manager:
                data = device_manager.collect_data()
                if data:
                    # 保存数据到数据库
                    db_manager.save_detection_data(session_id, data)
                    current_detection['data_points'] += 1
            
            # 根据采样频率控制循环间隔
            frequency = settings.get('frequency', 60)
            time.sleep(1.0 / frequency)
            
            # 检查是否达到设定时长
            duration = settings.get('duration', 0)
            if duration > 0:
                elapsed = (datetime.now() - current_detection['start_time']).total_seconds()
                if elapsed >= duration:
                    current_detection['status'] = 'completed'
                    break
        
        # 更新会话状态
        if current_detection:
            db_manager.update_session_status(
                session_id, 
                current_detection['status'],
                current_detection.get('data_points', 0)
            )
        
        logger.info(f'检测会话完成: {session_id}')
        
    except Exception as e:
        logger.error(f'检测线程异常: {e}')
        if current_detection:
            current_detection['status'] = 'error'
            current_detection['error'] = str(e)

# ==================== 错误处理 ====================

@app.errorhandler(404)
def not_found(error):
    return jsonify({'success': False, 'error': 'API接口不存在'}), 404

@app.errorhandler(500)
def internal_error(error):
    return jsonify({'success': False, 'error': '服务器内部错误'}), 500

if __name__ == '__main__':
    try:
        # 初始化应用
        init_app()
        
        # 启动Flask服务
        logger.info('启动后端服务...')
        app.run(
            host='127.0.0.1',
            port=5000,
            debug=False,
            threaded=True
        )
        
    except KeyboardInterrupt:
        logger.info('服务被用户中断')
    except Exception as e:
        logger.error(f'服务启动失败: {e}')
        sys.exit(1)
    finally:
        logger.info('后端服务已停止')