import configparser
import os

def load_camera_config(camera_name):
    """读取指定摄像头的配置, 并生成RTSP URL"""
    config = configparser.ConfigParser()
    # "项目根目录/config/camera_config.ini"
    config_path = os.path.join(
        os.path.dirname(os.path.dirname(__file__)),  # 项目根目录
        "config", 
        "camera_config.ini"
    )
    # 检查配置文件是否存在
    if not os.path.exists(config_path):
        raise FileNotFoundError(f"摄像头配置文件不存在：{config_path}")
    
    config.read(config_path, encoding="utf-8")
    
    if camera_name not in config.sections():
        raise ValueError(f"配置文件中未找到摄像头：{camera_name}")
    
    # 读取基础配置
    ip = config.get(camera_name, "ip")
    port = config.getint(camera_name, "port") 
    username = config.get(camera_name, "username")
    password = config.get(camera_name, "password")
    channel = config.get(camera_name, "channel")
    
    # 生成RTSP URL
    rtsp_url = f"rtsp://{username}:{password}@{ip}:{port}/streaming/channels/{channel}"
    
    return {
        "ip": ip,
        "port": port,
        "username": username,
        "password": password,
        "channel": channel,
        "rtsp_url": rtsp_url
    }