import os
from dotenv import load_dotenv
import redis

# 加载 .env 文件中的环境变量
basedir = os.path.abspath(os.path.dirname(__file__))
load_dotenv(os.path.join(basedir, '.env'))

class Config:
    """基础配置类"""
    SECRET_KEY = os.environ.get('SECRET_KEY') or 'a-hard-to-guess-string'
    SQLALCHEMY_TRACK_MODIFICATIONS = False
    
    # Session 配置
    SESSION_TYPE = 'redis'
    SESSION_PERMANENT = False
    SESSION_USE_SIGNER = True
    SESSION_REDIS = redis.from_url(os.environ.get('REDIS_URL'))

    @staticmethod
    def init_app(app):
        pass

class DevelopmentConfig(Config):
    """开发环境配置"""
    DEBUG = True
    # 数据库 URI
    DB_USER = os.environ.get('DB_USER')
    DB_PASSWORD = os.environ.get('DB_PASSWORD')
    DB_HOST = os.environ.get('DB_HOST')
    DB_NAME = os.environ.get('DB_NAME')
    SQLALCHEMY_DATABASE_URI = f'mysql+pymysql://{DB_USER}:{DB_PASSWORD}@{DB_HOST}/{DB_NAME}'

class ProductionConfig(Config):
    """生产环境配置"""
    DEBUG = False
    # 数据库 URI
    DB_USER = os.environ.get('DB_USER')
    DB_PASSWORD = os.environ.get('DB_PASSWORD')
    DB_HOST = os.environ.get('DB_HOST')
    DB_NAME = os.environ.get('DB_NAME')
    SQLALCHEMY_DATABASE_URI = f'mysql+pymysql://{DB_USER}:{DB_PASSWORD}@{DB_HOST}/{DB_NAME}'


# 方便地通过字典来选择配置
config = {
    'development': DevelopmentConfig,
    'production': ProductionConfig,
    'default': DevelopmentConfig
}