import os
from datetime import timedelta
import json
from pathlib import Path
from typing import Any


# 项目根目录
BASE_DIR = os.path.abspath(os.path.dirname(__file__))


def _get_bool_env(key: str, default: bool = False) -> bool:
    """从环境变量获取布尔值

    Args:
        key: 环境变量名
        default: 默认值

    Returns:
        布尔值
    """
    value = os.getenv(key)
    if value is None:
        return default
    return value.lower() in ("true", "1", "yes", "on")


def _load_env_file(env_dir: str | os.PathLike | None = None) -> bool:
    """从项目目录加载 .env 文件。"""
    try:
        from dotenv import load_dotenv

        search_dir = Path(env_dir or os.getenv("ITI_ENV_DIR") or os.getcwd()).resolve()
        env_name = os.getenv("FLASK_ENV", "dev")
        env_files = [
            ".env.local",
            f".env.{env_name}",
            ".env",
        ]

        for env_file in env_files:
            env_path = search_dir / env_file
            if env_path.exists():
                load_dotenv(env_path, override=False)
                return True
        return False
    except ImportError:
        return False


# 在定义配置类之前加载环境变量
_load_env_file()


class BaseConfig:
    """基础配置类 - 所有环境共享的配置"""

    BASE_DIR = BASE_DIR

    # 应用配置
    SECRET_KEY = os.getenv("SECRET_KEY", "dev-secret-key-change-in-production")

    # 数据库配置
    SQLALCHEMY_ENGINE_OPTIONS = {
        "json_serializer": lambda obj: json.dumps(obj, ensure_ascii=False),
        # "json_deserializer": json.loads,
    }
    SQLALCHEMY_TRACK_MODIFICATIONS = False
    SQLALCHEMY_RECORD_QUERIES = True
    SQLALCHEMY_ECHO = False
    SQLALCHEMY_COMMIT_ON_TEARDOWN = True
    SQLALCHEMY_SHOW_ERROR_DETAILS = True
    SQLALCHEMY_DATABASE_URI = os.getenv(
        "DATABASE_URL", f"sqlite:///{BASE_DIR}/runtime/iti-flask.db"
    )

    # JWT 配置
    JWT_SECRET_KEY = os.getenv("JWT_SECRET_KEY", "dev-jwt-secret-key")
    JWT_TOKEN_LOCATION = ["headers"]
    JWT_HEADER_NAME = "Authorization"
    JWT_HEADER_TYPE = "Bearer"
    JWT_ACCESS_TOKEN_EXPIRES = timedelta(hours=1)
    JWT_REFRESH_TOKEN_EXPIRES = timedelta(days=30)

    # 跨域配置
    CORS_ORIGINS = ["*"]

    # 限流配置
    RATELIMIT_ENABLED = True
    RATELIMIT_KEY_PREFIX = "iti_rate_limit_"
    RATELIMIT_STORAGE_URL = "memory://"
    RATELIMIT_STORAGE_URI = "memory://"
    RATELIMIT_DEFAULT = "200 per hour"

    # JSON 序列化配置
    JSON_ENSURE_ASCII = False  # 支持中文，不转义为 Unicode
    JSON_SORT_KEYS = False  # 不对 key 排序

    # 文件上传配置
    MAX_CONTENT_LENGTH = 200 * 1024 * 1024  # 200MB，Flask 上传大小限制

    # 缓存配置
    CACHE_SIMPLE = {
        # 类型 NullCache | SimpleCache | FileSystemCache | RedisCache | RedisSentinelCache | RedisClusterCache | UWSGICache | MemcachedCache | SASLMemcachedCache | SpreadSASLMemcachedCache
        "ENABLED": True,
        "CACHE_TYPE": "SimpleCache",
        "CACHE_NO_NULL_WARNING": False,
        "CACHE_ARGS": [],
        "CACHE_OPTIONS": None,
        "CACHE_DEFAULT_TIMEOUT": 0,
        "CACHE_IGNORE_ERRORS": False,
        "CACHE_THRESHOLD": 500,
        "CACHE_KEY_PREFIX": "iti_cache_",
        "CACHE_SOURCE_CHECK": False,
        # # UWSGI 配置
        # "CACHE_UWSGI_NAME": "mycache@localhost:3031",
        # # MEMCACHED 配置
        # "CACHE_MEMCACHED_SERVERS": ["localhost:11211"],
        # "CACHE_MEMCACHED_USERNAME": "None",
        # "CACHE_MEMCACHED_PASSWORD": "None",
        # # REDIS 配置
        # "CACHE_REDIS_URL": "redis://localhost:6379/2",
        # "CACHE_REDIS_HOST": "localhost",
        # "CACHE_REDIS_PORT": 6379,
        # "CACHE_REDIS_PASSWORD": None,
        # "CACHE_REDIS_DB": 0,
        # "CACHE_REDIS_SENTINELS": ["localhost:26379"],
        # "CACHE_REDIS_SENTINEL_MASTER": "mymaster",
        # "CACHE_REDIS_CLUSTER": "localhost:6379,localhost:6380,localhost:6381",
        # # FILE-SYSTEM 配置
        # "CACHE_DIR": r"/tmp/iti_cache",
    }

    # Redis缓存配置
    CACHE_REDIS = {
        "ENABLED": False,
        "CACHE_TYPE": "RedisCache",
        "CACHE_NO_NULL_WARNING": False,
        "CACHE_ARGS": [],
        "CACHE_OPTIONS": None,
        "CACHE_DEFAULT_TIMEOUT": 0,
        "CACHE_IGNORE_ERRORS": False,
        "CACHE_THRESHOLD": 500,
        "CACHE_KEY_PREFIX": "iti_cache_",
        "CACHE_SOURCE_CHECK": False,
        # REDIS 配置
        # "CACHE_REDIS_URL": "redis://localhost:6379/0",
        "CACHE_REDIS_HOST": "localhost",
        "CACHE_REDIS_PORT": 6379,
        "CACHE_REDIS_PASSWORD": None,
        "CACHE_REDIS_DB": 0,
        # "CACHE_REDIS_SENTINELS": ["localhost:26379"],
        # "CACHE_REDIS_SENTINEL_MASTER": "mymaster",
        # "CACHE_REDIS_CLUSTER": "localhost:6379,localhost:6380,localhost:6381",
    }

    # 文件存储配置
    FILE_STORAGE = {
        "DEFAULT_STORAGE_TYPE": "local",
        "MAX_FILE_SIZE": 100 * 1024 * 1024 * 1024,  # 100GB
        "TUS_CHUNK_SIZE": 5 * 1024 * 1024,  # 5MB
        # 本地存储配置
        "LOCAL": {
            "base_path": os.path.join(BASE_DIR, "runtime", "uploads"),
        },
        # 阿里云OSS配置
        "ALIYUN_OSS": {
            "access_key_id": os.getenv("ALIYUN_OSS_ACCESS_KEY_ID"),
            "access_key_secret": os.getenv("ALIYUN_OSS_ACCESS_KEY_SECRET"),
            "endpoint": os.getenv(
                "ALIYUN_OSS_ENDPOINT"
            ),  # 例如：oss-cn-hangzhou.aliyuncs.com
            "bucket": os.getenv("ALIYUN_OSS_BUCKET"),
        },
        # 腾讯云COS配置
        "TENCENT_COS": {
            "secret_id": os.getenv("TENCENT_COS_SECRET_ID"),
            "secret_key": os.getenv("TENCENT_COS_SECRET_KEY"),
            "region": os.getenv("TENCENT_COS_REGION"),  # 例如：ap-guangzhou
            "bucket": os.getenv("TENCENT_COS_BUCKET"),
        },
        # 七牛云Kodo配置
        "QINIU_KODO": {
            "access_key": os.getenv("QINIU_KODO_ACCESS_KEY"),
            "secret_key": os.getenv("QINIU_KODO_SECRET_KEY"),
            "bucket": os.getenv("QINIU_KODO_BUCKET"),
            "domain": os.getenv("QINIU_KODO_DOMAIN"),  # CDN域名
        },
        # 华为云OBS配置
        "HUAWEI_OBS": {
            "access_key_id": os.getenv("HUAWEI_OBS_ACCESS_KEY_ID"),
            "secret_access_key": os.getenv("HUAWEI_OBS_SECRET_ACCESS_KEY"),
            "server": os.getenv(
                "HUAWEI_OBS_SERVER"
            ),  # 例如：obs.cn-north-4.myhuaweicloud.com
            "bucket": os.getenv("HUAWEI_OBS_BUCKET"),
        },
    }

    # 是否启用业务项目自带 SPA 静态文件承载。
    # 框架不内置前端产物；启用后从业务项目 FRONTEND_PATH 读取文件。
    FRONTEND_ENABLED = _get_bool_env("FRONTEND_ENABLED", False)
    FRONTEND_PATH = os.getenv("FRONTEND_PATH", "")

    # 服务调用配置。业务项目按需添加具体服务。
    SERVICES: dict[str, dict[str, Any]] = {}

    # 轻量任务配置。多进程部署时只应在一个专用实例启用。
    TASKS_ENABLED = False


class DevConfig(BaseConfig):
    """开发环境配置"""

    DEBUG = True
    TESTING = False

    # 开发环境数据库
    SQLALCHEMY_DATABASE_URI = os.getenv(
        "DATABASE_URL", f"sqlite:///{BASE_DIR}/runtime/iti-flask_dev.db"
    )
    SQLALCHEMY_ECHO = True  # 开发环境打印 SQL
    SQLALCHEMY_SHOW_ERROR_DETAILS = True

    # JSON 配置（开发环境：格式化输出，方便调试）
    JSON_INDENT = 2  # 缩进 2 个空格
    JSON_SEPARATORS = (", ", ": ")  # 使用空格分隔

    # JWT 开发环境配置
    JWT_ACCESS_TOKEN_EXPIRES = timedelta(hours=24)  # 开发环境延长有效期
    # JWT_ACCESS_TOKEN_EXPIRES = timedelta(seconds=5)  # 测试过期

    # 限流配置（开发环境较宽松）
    RATELIMIT_ENABLED = True
    RATELIMIT_DEFAULT = "1000 per hour"


class TestConfig(BaseConfig):
    """测试环境配置"""

    DEBUG = False
    TESTING = True

    # 测试数据库（使用内存数据库）
    SQLALCHEMY_DATABASE_URI = "sqlite:///:memory:"
    SQLALCHEMY_ECHO = False
    SQLALCHEMY_SHOW_ERROR_DETAILS = False

    # JSON 配置（测试环境：与生产一致）
    JSON_INDENT = None  # 不缩进
    JSON_SEPARATORS = (",", ":")  # 紧凑分隔符

    # 限流配置
    RATELIMIT_ENABLED = False  # 测试环境禁用限流


class ProdConfig(BaseConfig):
    """生产环境配置"""

    DEBUG = False
    TESTING = False

    # 生产环境必须使用环境变量
    SECRET_KEY = os.getenv("SECRET_KEY", "")
    JWT_SECRET_KEY = os.getenv("JWT_SECRET_KEY", "")

    # 生产环境数据库
    SQLALCHEMY_DATABASE_URI = os.getenv(
        "DATABASE_URL", f"sqlite:///{BASE_DIR}/runtime/iti-flask_prod.db"
    )

    # 处理 PostgreSQL URL 格式
    if SQLALCHEMY_DATABASE_URI and SQLALCHEMY_DATABASE_URI.startswith("postgres://"):
        SQLALCHEMY_DATABASE_URI = SQLALCHEMY_DATABASE_URI.replace(
            "postgres://", "postgresql://", 1
        )

    SQLALCHEMY_SHOW_ERROR_DETAILS = False

    # 限流配置（生产环境严格）
    RATELIMIT_STORAGE_URL = os.getenv("REDIS_URL", "memory://")
    RATELIMIT_DEFAULT = "100 per hour"

    # JSON 配置（生产环境：紧凑输出，减小体积）
    JSON_INDENT = None  # 不缩进
    JSON_SEPARATORS = (",", ":")  # 紧凑分隔符

    # 性能优化
    SQLALCHEMY_POOL_SIZE = 10
    SQLALCHEMY_POOL_TIMEOUT = 30
    SQLALCHEMY_POOL_RECYCLE = 3600


# 配置字典
config = {
    "dev": DevConfig,
    "test": TestConfig,
    "prod": ProdConfig,
    "default": DevConfig,
}


def get_config(env_name=None):
    """
    根据环境名称获取配置类

    Args:
        env_name: 环境名称 ('dev', 'test', 'prod')
                  如果为 None 则从环境变量 FLASK_ENV 读取

    Returns:
        配置类
    """
    if env_name is None:
        env_name = os.getenv("FLASK_ENV", "dev")

    return config.get(env_name, config["default"])