"""API 服务配置 — 继承 SharedSettings，只追加 API 特有字段。

通用配置统一在 packages/config/base.py 的 SharedSettings 中定义，这里不重复。
历史上 API 端使用 UPPER_CASE 命名风格的字段，目前通过 property 别名向后兼容。
新代码统一使用 snake_case（继承自 SharedSettings）。
"""

import os
from typing import Optional

from pydantic import AliasChoices, Field, field_validator
from pydantic_settings import SettingsConfigDict

from packages.config.base import SharedSettings, get_cached_settings


class APISettings(SharedSettings):
    """API 服务专用配置。

    通用配置继承自 SharedSettings，这里只定义 API 独有字段。
    """

    # ── 应用基本信息 ────────────────────────────────────────────────────
    app_name: str = "xiaoxia-saas"
    app_version: str = "0.1.61"

    # 应用基础 URL，用于生成认证邮件中的链接
    app_base_url: str = "http://localhost:3000"

    # Container bind address; external expose is controlled by Docker/Nginx.
    api_host: str = "0.0.0.0"  # nosec: B104
    api_port: int = 8000

    # ── 数据库特有 ──────────────────────────────────────────────────────
    use_in_memory_db: bool = False

    # ── Redis 特有 ──────────────────────────────────────────────────────
    enable_redis_sessions: bool = False

    # ── JWT ────────────────────────────────────────────────────────────
    # JWT secret key - MUST be set via environment variable, no default allowed
    jwt_secret_key: Optional[str] = None

    # JWT 算法与过期时间
    jwt_algorithm: str = "HS256"
    jwt_access_token_expire_minutes: int = 30
    jwt_refresh_token_expire_days: int = 30

    @field_validator("jwt_secret_key", mode="before")
    @classmethod
    def validate_jwt_secret_key(cls, v):
        if v is None or v == "":
            raise ValueError(
                "JWT_SECRET_KEY must be set via environment variable. " "Do not use default value in production!"
            )
        # Block known insecure default values
        insecure_defaults = [
            "your-secret-key-change-in-production",
            "your-secret-key",
            "secret",
            "changeme",
            "password",
        ]
        if v.lower() in [d.lower() for d in insecure_defaults]:
            raise ValueError(
                f"JWT_SECRET_KEY '{v}' is insecure. " "Please set a strong random secret via environment variable."
            )
        return v

    # ── 邮件 ────────────────────────────────────────────────────────────
    enable_email_delivery: bool = False
    smtp_host: str = "smtp.gmail.com"
    smtp_port: int = 587
    smtp_user: str = ""
    smtp_password: str = ""
    smtp_from_email: str = ""
    smtp_from_name: str = "小虾 SaaS"
    smtp_use_tls: bool = True

    # ── OSS 特有校验 ────────────────────────────────────────────────────
    @field_validator("oss_access_key_id", mode="before")
    @classmethod
    def validate_oss_access_key_id(cls, v):
        if (v is None or v == "") and os.getenv("APP_ENV", "development") != "development":
            raise ValueError(
                "OSS_ACCESS_KEY_ID must be set via environment variable in non-development environments. "
                "Check the server .env file (e.g. /var/lib/xiaoxia-saas-staging/.env)."
            )
        return v or ""

    @field_validator("oss_access_key_secret", mode="before")
    @classmethod
    def validate_oss_access_key_secret(cls, v):
        if (v is None or v == "") and os.getenv("APP_ENV", "development") != "development":
            raise ValueError(
                "OSS_ACCESS_KEY_SECRET must be set via environment variable in non-development environments. "
                "Check the server .env file (e.g. /var/lib/xiaoxia-saas-staging/.env)."
            )
        return v or ""

    oss_direct_upload_max_mb: int = Field(
        default=2000,
        validation_alias=AliasChoices("oss_direct_upload_max_mb", "max_upload_size_mb"),
    )

    # ── CORS ────────────────────────────────────────────────────────────
    cors_origins_raw: str = "http://localhost:3000,http://localhost:5173,http://localhost:8000"

    # ── 渲染引擎 ────────────────────────────────────────────────────────
    # 渲染引擎选择：legacy=旧VideoComposeService，unified=新UnifiedRenderService
    render_engine: str = "legacy"

    model_config = SettingsConfigDict(
        env_file=".env",
        env_file_encoding="utf-8",
        case_sensitive=False,
        extra="ignore",
    )

    @property
    def cors_origins(self) -> list[str]:
        return [origin.strip() for origin in self.cors_origins_raw.split(",") if origin.strip()]

    # ── 向后兼容：UPPER_CASE property 别名 ──────────────────────────────
    # 新代码请使用 snake_case（继承的字段名），以下别名仅用于兼容旧代码

    @property
    def APP_NAME(self) -> str:
        return self.app_name

    @property
    def APP_VERSION(self) -> str:
        return self.app_version

    @property
    def ENVIRONMENT(self) -> str:
        return self.environment

    @property
    def DEBUG(self) -> bool:
        return self.debug

    @property
    def APP_BASE_URL(self) -> str:
        return self.app_base_url

    @property
    def API_HOST(self) -> str:
        return self.api_host

    @property
    def API_PORT(self) -> int:
        return self.api_port

    @property
    def DATABASE_URL(self) -> str:
        return self.database_url

    @property
    def DATABASE_POOL_SIZE(self) -> int:
        return self.database_pool_size

    @property
    def DATABASE_MAX_OVERFLOW(self) -> int:
        return self.database_max_overflow

    @property
    def DATABASE_POOL_TIMEOUT(self) -> int:
        return self.database_pool_timeout

    @property
    def DATABASE_POOL_RECYCLE(self) -> int:
        return self.database_pool_recycle

    @property
    def USE_IN_MEMORY_DB(self) -> bool:
        return self.use_in_memory_db

    @property
    def AUTO_CREATE_SCHEMA(self) -> bool:
        return self.auto_create_schema

    @property
    def REDIS_URL(self) -> str:
        return self.redis_url

    @property
    def ENABLE_REDIS_SESSIONS(self) -> bool:
        return self.enable_redis_sessions

    @property
    def JWT_SECRET_KEY(self) -> Optional[str]:
        return self.jwt_secret_key

    @property
    def JWT_ALGORITHM(self) -> str:
        return self.jwt_algorithm

    @property
    def JWT_ACCESS_TOKEN_EXPIRE_MINUTES(self) -> int:
        return self.jwt_access_token_expire_minutes

    @property
    def JWT_REFRESH_TOKEN_EXPIRE_DAYS(self) -> int:
        return self.jwt_refresh_token_expire_days

    @property
    def ENABLE_EMAIL_DELIVERY(self) -> bool:
        return self.enable_email_delivery

    @property
    def SMTP_HOST(self) -> str:
        return self.smtp_host

    @property
    def SMTP_PORT(self) -> int:
        return self.smtp_port

    @property
    def SMTP_USER(self) -> str:
        return self.smtp_user

    @property
    def SMTP_PASSWORD(self) -> str:
        return self.smtp_password

    @property
    def SMTP_FROM_EMAIL(self) -> str:
        return self.smtp_from_email

    @property
    def SMTP_FROM_NAME(self) -> str:
        return self.smtp_from_name

    @property
    def SMTP_USE_TLS(self) -> bool:
        return self.smtp_use_tls

    @property
    def CELERY_BROKER_URL(self) -> str:
        return self.celery_broker_url

    @property
    def CELERY_RESULT_BACKEND(self) -> str:
        return self.celery_result_backend

    @property
    def OSS_ENDPOINT(self) -> str:
        return self.oss_endpoint

    @property
    def OSS_ACCESS_KEY_ID(self) -> str:
        return self.oss_access_key_id

    @property
    def OSS_ACCESS_KEY_SECRET(self) -> str:
        return self.oss_access_key_secret

    @property
    def OSS_BUCKET_NAME(self) -> str:
        return self.oss_bucket_name

    @property
    def OSS_DIRECT_UPLOAD_MAX_MB(self) -> int:
        return self.oss_direct_upload_max_mb

    @property
    def OSS_DIRECT_UPLOAD_EXPIRE_SECONDS(self) -> int:
        return self.oss_direct_upload_expire_seconds

    @property
    def CORS_ORIGINS_RAW(self) -> str:
        return self.cors_origins_raw

    @property
    def CORS_ORIGINS(self) -> list[str]:
        return self.cors_origins

    @property
    def RENDER_ENGINE(self) -> str:
        return self.render_engine


def get_api_settings() -> APISettings:
    """获取 API 配置单例（统一入口）。"""
    return get_cached_settings(APISettings)