"""基金行情公共契约。内部使用稳定英文字段，不暴露供应商字段名。"""

from datetime import date, datetime
from decimal import Decimal
from typing import Literal

from pydantic import BaseModel, ConfigDict, Field, field_validator, model_validator


class FundQuoteQuery(BaseModel):
    model_config = ConfigDict(extra="forbid", frozen=True)

    fund_codes: tuple[str, ...] = ()
    fund_type: str | None = None
    target_date: date | None = None
    limit: int = Field(default=50, ge=1, le=1000)

    @field_validator("fund_codes")
    @classmethod
    def validate_codes(cls, value: tuple[str, ...]) -> tuple[str, ...]:
        for code in value:
            if len(code) != 6 or not code.isdigit():
                raise ValueError("fund code must be a six-digit number")
        return tuple(dict.fromkeys(value))


class FundQuote(BaseModel):
    model_config = ConfigDict(extra="forbid", frozen=True)

    fund_code: str
    fund_name: str
    fund_type: str | None = None
    nav: Decimal | None = None
    nav_date: date | None = None
    daily_change: Decimal | None = None
    half_year_return: Decimal | None = None
    one_year_return: Decimal | None = None
    year_to_date_return: Decimal | None = None
    since_inception_return: Decimal | None = None
    quote_time: datetime
    quote_source: Literal["eastmoney", "cache", "degraded"]
    is_intraday: bool
    degraded: bool = False

class FundTrendQuery(BaseModel):
    """`E6` 行情走势出口的入参（`W27` / `D3.9` §4.2）。

    **只收实体，不收问句**：`fund_code` 与 `fund_name` 至少给一个 —— 由 Agent 侧
    「表层判定层」抽好再传，工具自己不做自然语言理解。这样"抽错实体"与"查不到数据"
    是两类可分开归因、分开回归的失败。
    """

    model_config = ConfigDict(extra="forbid", frozen=True)

    #: 6 位场内代码（最确定的实体）
    fund_code: str | None = None
    #: 产品名（需在 `fin_product.product_name` 里**唯一**命中，否则判 `ambiguous`）
    fund_name: str | None = None
    #: 取多少个**净值日**（不是自然日，见 `fund_trend_service` 的口径说明）
    days: int = Field(default=120, ge=5, le=365)

    @field_validator("fund_code")
    @classmethod
    def validate_code(cls, value: str | None) -> str | None:
        if value is None:
            return None
        text = value.strip()
        if len(text) != 6 or not text.isdigit():
            raise ValueError("fund code must be a six-digit number")
        return text

    @model_validator(mode="after")
    def require_entity(self) -> "FundTrendQuery":
        if not (self.fund_code or (self.fund_name or "").strip()):
            raise ValueError("fund_code or fund_name is required")
        return self