import os
from datetime import timedelta
from dotenv import load_dotenv

load_dotenv()

BASE_DIR = os.path.dirname(os.path.abspath(__file__))


class Config:
    SECRET_KEY = os.environ.get('SECRET_KEY', 'dev-secret-key-please-change')
    SQLALCHEMY_DATABASE_URI = os.environ.get(
        'DATABASE_URL',
        'mysql+pymysql://root:password@localhost:3306/resource_library'
    )
    SQLALCHEMY_TRACK_MODIFICATIONS = False

    # 上传配置
    UPLOAD_FOLDER = os.path.join(BASE_DIR, 'app', 'static', 'uploads')
    MAX_CONTENT_LENGTH = int(os.environ.get('MAX_UPLOAD_SIZE_MB', 500)) * 1024 * 1024

    # Session
    PERMANENT_SESSION_LIFETIME = timedelta(hours=24)
    SESSION_COOKIE_HTTPONLY = True
    SESSION_COOKIE_SAMESITE = 'Lax'

    # CSRF
    WTF_CSRF_ENABLED = True
    WTF_CSRF_TIME_LIMIT = 3600

    # 允许的文件类型
    ALLOWED_TEXT_EXT = {'txt', 'md', 'csv', 'json', 'xml', 'log', 'html', 'htm'}
    ALLOWED_IMAGE_EXT = {'jpg', 'jpeg', 'png', 'gif', 'webp', 'bmp', 'svg', 'ico'}
    ALLOWED_AUDIO_EXT = {'mp3', 'wav', 'ogg', 'flac', 'm4a', 'aac', 'wma'}
    ALLOWED_VIDEO_EXT = {'mp4', 'webm', 'avi', 'mkv', 'mov', 'wmv', 'flv', 'm4v'}

    @classmethod
    def all_allowed_extensions(cls):
        return (cls.ALLOWED_TEXT_EXT | cls.ALLOWED_IMAGE_EXT |
                cls.ALLOWED_AUDIO_EXT | cls.ALLOWED_VIDEO_EXT)


class DevelopmentConfig(Config):
    DEBUG = True


class ProductionConfig(Config):
    DEBUG = False
    SESSION_COOKIE_SECURE = True
    WTF_CSRF_SSL_STRICT = True


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