from functools import lru_cache
from pathlib import Path

from dotenv import load_dotenv
from pydantic_settings import BaseSettings, SettingsConfigDict

# .env 在仓库根（server/ 的上一级），供各部分共用
_ROOT_DIR = Path(__file__).resolve().parents[2]
load_dotenv(_ROOT_DIR / ".env")


class Settings(BaseSettings):
    """运行时与密钥。模型清单见 config/models.yaml。"""

    model_config = SettingsConfigDict(
        env_file=str(_ROOT_DIR / ".env"),
        env_file_encoding="utf-8",
        extra="ignore",
    )

    # ── AI 密钥 ──
    deepseek_api_key: str = ""
    openai_api_key: str = ""
    dashscope_api_key: str = ""
    # 华北2（北京）业务空间时需填：https://{WorkspaceId}.cn-beijing.maas.aliyuncs.com/api/v1
    dashscope_base_http_api_url: str = ""

    # ── 运行 ──
    host: str = "127.0.0.1"
    port: int = 8800
    cors_origins: str = ""

    # ── V2：数据层 ──
    # 本地过渡用 SQLite；上线切 PostgreSQL：postgresql+asyncpg://user:pass@host:5432/ozon_seller
    database_url: str = "sqlite+aiosqlite:///./data/app.db"

    # 店铺凭证 AES-GCM 加密密钥（shops/categories/publish 冻结链路使用；
    # 鉴权/账户体系已按 V2.1 决策移除，后续引入账户时一并重做）
    secret_key: str = ""

    # ── V2：七牛（图片存储）──
    qiniu_access_key: str = ""
    qiniu_secret_key: str = ""
    qiniu_bucket: str = ""
    qiniu_domain: str = ""       # 绑定域名，如 https://cdn.example.com
    # 为空时用本地文件系统兜底（开发期），不为空时走七牛
    storage_backend: str = "local"  # local | qiniu

    # ── V2：对外地址（插件/前端回写、生成图回调）──
    app_base_url: str = "http://127.0.0.1:8800"

    # ── 图片与导出资源上限（字节）──
    # 单张图片在后端需要解码/加水印，限制单文件可避免一次请求耗尽内存。
    image_upload_max_bytes: int = 20 * 1024 * 1024
    image_download_max_bytes: int = 20 * 1024 * 1024
    # 图片解码前依据真实宽高限制像素，避免超大图耗尽 Pillow/水印处理内存。
    image_max_pixels: int = 40_000_000
    # 远程图片下载防护：连接/读写/总耗时分别受控；重定向逐跳校验目标地址。
    image_download_connect_timeout: float = 10.0
    image_download_read_timeout: float = 30.0
    image_download_total_timeout: float = 60.0
    image_download_max_redirects: int = 3
    collection_max_images: int = 100
    export_max_images: int = 50
    export_zip_max_bytes: int = 200 * 1024 * 1024
    # ZIP 超过该值自动落临时磁盘，不继续占用进程内存。
    export_zip_memory_threshold_bytes: int = 2 * 1024 * 1024

    # ── 商品轮播视频（FFmpeg）──
    # Ubuntu 默认安装包会提供同名命令；容器或特殊路径可在 .env 覆盖。
    video_ffmpeg_path: str = "ffmpeg"
    video_ffprobe_path: str = "ffprobe"
    video_width: int = 810
    video_height: int = 1080
    video_fps: int = 30
    video_transition_seconds: float = 0.35
    video_crf: int = 22
    video_max_rate: str = "3M"
    video_buffer_size: str = "6M"
    video_max_bytes: int = 45 * 1024 * 1024
    video_max_duration_seconds: int = 180
    video_render_timeout_seconds: int = 120
    background_job_lease_seconds: int = 300

    # ── V2.1 套图生图（provider 路由与 image-suite-studio 一致）──
    image_provider: str = "doubao"      # 未知模型时的兜底 provider：doubao | tongyi | rightapi
    request_timeout: int = 300          # 单张生图请求超时（秒）
    poll_max_wait: int = 600            # 异步任务轮询上限（秒）
    # 水印徽章源图（图片水印用，可 .env 覆盖）
    watermark_image_path: str = str(Path(__file__).resolve().parents[1] / "assets" / "watermark.jpg")

    # 豆包 / 火山方舟 Seedream
    ark_api_key: str = ""
    ark_base_url: str = "https://ark.cn-beijing.volces.com/api/v3/images/generations"
    ark_image_model: str = "doubao-seedream-4-5-251128"

    # 通义 / DashScope（key 复用上方 dashscope_api_key；dashscope_base_http_api_url 是业务空间专用，与此处无关）
    dashscope_model: str = "wan2.7-image-pro"
    dashscope_base_url: str = ""        # 留空按模型自动选择万象异步/千问同步端点

    # RightAPI（OpenAI 兼容中转：gpt-image / nano-banana 系列）
    rightapi_api_key: str = ""
    rightapi_base_url: str = "https://rightapi.ai/draw"
    rightapi_image_model: str = "gpt-image-2"
    rightapi_max_retries: int = 3       # 429/5xx/超时的重试次数（1 = 不重试）
    rightapi_retry_wait: int = 60       # 重试基础等待秒数，按 60→120→240 递增

    # Pcore（OpenAI 兼容中转：pcore.ai，异步图片任务；模型值带 @pcore 后缀路由到此）
    pcore_api_key: str = ""
    pcore_base_url: str = "https://pcore.ai"
    pcore_max_retries: int = 3          # 429/5xx/超时的重试次数（1 = 不重试）
    pcore_retry_wait: int = 60          # 重试基础等待秒数，按 60→120→240 递增

    # DeepSeek 出图方案规划器（key 复用上方 deepseek_api_key；文案生成的模型走 config/models.yaml，互不影响）
    deepseek_base_url: str = "https://api.deepseek.com/v1"
    deepseek_model: str = "deepseek-v4-flash"

    @property
    def cors_origin_list(self) -> list[str]:
        if not self.cors_origins.strip():
            return []
        return [o.strip() for o in self.cors_origins.split(",") if o.strip()]

    @property
    def use_qiniu(self) -> bool:
        return self.storage_backend == "qiniu" and bool(
            self.qiniu_access_key and self.qiniu_secret_key and self.qiniu_bucket
        )


@lru_cache
def get_settings() -> Settings:
    return Settings()