"""策略领域实体（M8.3，v2 §17/§5.3）。

Strategy = 完整策略定义（universe + factors + selection + rebalance + costs +
portfolio，除回测区间 period 外），保存为命名资产；回测时补 period 展开为
ResearchSpec（v2 §18 Research Specification 为统一契约，策略是其持久化形态）。
"""

from __future__ import annotations

from datetime import date, datetime

from pydantic import BaseModel, Field

from app.domain.entities.research import (
    CostSpec,
    FactorSpec,
    PortfolioSpec,
    SelectionSpec,
    UniverseSpec,
)


class StrategyDefinition(BaseModel):
    id: str = ""
    name: str = Field(min_length=1, max_length=64)
    description: str = ""
    spec_type: str = Field(default="backtest", pattern="^(backtest|factor_test)$")
    universe: UniverseSpec = UniverseSpec()
    price_adjustment: str = Field(default="none", pattern="^(none|qfq)$")
    factors: list[FactorSpec] = Field(min_length=1)
    selection: SelectionSpec = SelectionSpec()
    rebalance: str = Field(default="monthly", pattern="^(weekly|monthly)$")
    costs: CostSpec = CostSpec()
    portfolio: PortfolioSpec = PortfolioSpec()
    version: str = "1"
    created_at: datetime | None = None

    def to_research_spec(self, period: tuple[date, date], initial_capital: float | None = None):
        """补全回测区间/资金后展开为标准 ResearchSpec（可在 Job/回测执行）。"""
        from app.domain.entities.research import ResearchSpec

        return ResearchSpec(
            type=self.spec_type,
            universe=self.universe,
            price_adjustment=self.price_adjustment,
            factors=self.factors,
            selection=self.selection,
            rebalance=self.rebalance,
            period=period,
            costs=self.costs,
            portfolio=self.portfolio,
            initial_capital=initial_capital if initial_capital else 1_000_000.0,
        )