"""套图业务逻辑（从 api/suite.py 下沉）：文本素材转换 / 模型校验 / 生成图回写商品素材。

api 层只留参数校验与调用；本模块可独立测试。
"""
from __future__ import annotations

import uuid

from schemas.suite import TextMaterial
from services.tasks import TaskImage


def texts_to_raw(texts: list[TextMaterial]) -> dict:
    """前端组装的文本素材 → prompt 上下文用的 raw dict（后写的覆盖先写的）。"""
    raw: dict = {}
    for t in texts:
        if t.kind == "title" and t.content:
            raw["title"] = t.content
        elif t.kind == "price" and t.content:
            raw["price"] = t.content
        elif t.kind == "brand" and t.content:
            raw["brand"] = t.content
        elif t.kind == "params" and t.pairs:
            merged = {p["key"]: p["value"] for p in (raw.get("params") or [])}
            for p in t.pairs:
                merged.setdefault(p["key"], p["value"])
            raw["params"] = [{"key": k, "value": v} for k, v in merged.items()]
        elif t.kind == "selling_point" and t.content:
            raw["sellingPoints"] = t.content
        elif t.kind == "desc" and t.content:
            raw["desc"] = t.content
        elif t.kind == "sales" and t.content:
            raw["sales"] = t.content
        elif t.kind == "shop" and t.content:
            raw["shop"] = t.content
    return raw


def validate_model(provider_name: str, model: str | None) -> None:
    """按 provider 校验模型名白名单，不合法抛 ValueError。"""
    from schemas.suite import RIGHTAPI_MODELS, TONGYI_MODELS

    if provider_name == "tongyi" and model and model not in TONGYI_MODELS:
        raise ValueError(f"不支持的模型: {model}（tongyi 支持: {TONGYI_MODELS}）")
    if provider_name == "rightapi" and model and model not in RIGHTAPI_MODELS:
        raise ValueError(f"不支持的模型: {model}（rightapi 支持: {RIGHTAPI_MODELS}）")


async def append_generated_asset(
    product_id: str,
    image: TaskImage,
    after_asset_id: str | None = None,
) -> str | None:
    """把一张生成完成的图追加为 product_assets(generated)，并累加 asset_counts。返回 asset_id。

    after_asset_id：插入锚点——新素材排在锚点之后（其余素材顺次后移），方便与原图对比；
    缺省/锚点无效时追加到组尾。作为 run_suite 的逐张回调使用时签名须为 (image)，
    调用方用 partial 绑定 product_id。
    """
    from sqlalchemy import func, select

    from db import get_session_factory
    from models import Product, ProductAsset

    pid = uuid.UUID(product_id)
    async with get_session_factory()() as db:
        sort_order: int | None = None
        if after_asset_id:
            try:
                anchor = await db.get(ProductAsset, UUID(after_asset_id))
            except ValueError:
                anchor = None
            if anchor is not None and anchor.product_id == pid and anchor.group_key == "generated":
                # 锚点之后的素材顺次后移，腾出插入位
                followers = (
                    await db.scalars(
                        select(ProductAsset).where(
                            ProductAsset.product_id == pid,
                            ProductAsset.group_key == "generated",
                            ProductAsset.sort_order > anchor.sort_order,
                        )
                    )
                ).scalars().all()
                for follower in followers:
                    follower.sort_order += 1
                sort_order = anchor.sort_order + 1

        if sort_order is None:
            sort_order = await db.scalar(
                select(func.coalesce(func.max(ProductAsset.sort_order), -1)).where(
                    ProductAsset.product_id == pid,
                    ProductAsset.group_key == "generated",
                )
            )
            sort_order = (sort_order or 0) + 1

        asset = ProductAsset(
            product_id=pid,
            group_key="generated",
            variant_name=None,
            sort_order=sort_order,
            type="img",
            source_url="",
            stored_url=image.url,
            status="uploaded",
        )
        db.add(asset)
        await db.flush()

        product = await db.get(Product, pid)
        if product is not None:
            counts = dict(product.asset_counts or {})
            counts["generated"] = int(counts.get("generated") or 0) + 1
            product.asset_counts = counts
        await db.commit()
        return str(asset.id)