import os
from datetime import timedelta

class Config:
    # 基础配置
    SECRET_KEY = os.environ.get('SECRET_KEY', 'a1b2c3d4e5f6g7h8i9j0k1l2m3n4o5p6q7r8s9t0u1v2w3x4y5z6a7b8c9d0e1f2')
    
    # MySQL 数据库配置
    MYSQL_HOST = os.environ.get('MYSQL_HOST', 'localhost')
    MYSQL_PORT = int(os.environ.get('MYSQL_PORT', 3306))
    MYSQL_USER = os.environ.get('MYSQL_USER', 'linguotree')
    MYSQL_PASSWORD = os.environ.get('MYSQL_PASSWORD', 'adminzhf')
    MYSQL_DATABASE = os.environ.get('MYSQL_DATABASE', 'linguotree_db')
    
    SQLALCHEMY_DATABASE_URI = f'mysql+pymysql://{MYSQL_USER}:{MYSQL_PASSWORD}@{MYSQL_HOST}:{MYSQL_PORT}/{MYSQL_DATABASE}'
    SQLALCHEMY_TRACK_MODIFICATIONS = False
    SQLALCHEMY_ENGINE_OPTIONS = {
        'pool_recycle': 300,
        'pool_pre_ping': True
    }
    
    # 文件上传配置
    UPLOAD_FOLDER = 'static/uploads'
    MAX_CONTENT_LENGTH = 16 * 1024 * 1024  # 16MB
    
    # 会话配置
    PERMANENT_SESSION_LIFETIME = timedelta(days=7)
    
    # 网站信息
    SITE_NAME = "Linguotree"
    SITE_DOMAIN = "www.linguotree.com"
    
    # 邮件配置（可选）
    MAIL_SERVER = os.environ.get('MAIL_SERVER', 'smtp.gmail.com')
    MAIL_PORT = int(os.environ.get('MAIL_PORT', 587))
    MAIL_USE_TLS = True
    MAIL_USERNAME = os.environ.get('MAIL_USERNAME')
    MAIL_PASSWORD = os.environ.get('MAIL_PASSWORD')

class DevelopmentConfig(Config):
    DEBUG = True
    TESTING = False

class ProductionConfig(Config):
    DEBUG = False
    TESTING = False

config = {
    'development': DevelopmentConfig,
    'production': ProductionConfig,
    'default': DevelopmentConfig
}