from decimal import Decimal, InvalidOperation

from pydantic import BaseModel, Field, field_validator


def _validate_decimal_amount(value: Decimal) -> Decimal:
    try:
        normalized = Decimal(value)
    except (InvalidOperation, TypeError, ValueError) as exc:
        raise ValueError("Некорректная сумма") from exc

    if not normalized.is_finite():
        raise ValueError("Некорректная сумма")

    return normalized


class DeleteResponse(BaseModel):
    status: str


class PricingCategoryCreateRequest(BaseModel):
    name: str = Field(..., min_length=1, max_length=255)
    code: str | None = Field(default=None, max_length=128)


class PricingCategoryUpdateRequest(BaseModel):
    name: str = Field(..., min_length=1, max_length=255)
    code: str | None = Field(default=None, max_length=128)


class PricingCategoryItem(BaseModel):
    pricing_category_id: str
    scheme_id: str
    name: str
    code: str | None
    created_at: str


class PricingCategoryCreateResponse(BaseModel):
    pricing_category_id: str
    scheme_id: str
    name: str
    code: str | None


class PricingCategoryUpdateResponse(BaseModel):
    pricing_category_id: str
    scheme_id: str
    name: str
    code: str | None


class PriceRuleCreateRequest(BaseModel):
    pricing_category_id: str | None = Field(default=None, max_length=32)
    target_type: str = Field(..., pattern="^(seat|group|sector)$")
    target_ref: str = Field(..., min_length=1, max_length=128)
    amount: Decimal
    currency: str = Field(default="RUB", min_length=3, max_length=8)

    @field_validator("amount")
    @classmethod
    def validate_amount(cls, value: Decimal) -> Decimal:
        return _validate_decimal_amount(value)


class PriceRuleUpdateRequest(BaseModel):
    pricing_category_id: str | None = Field(default=None, max_length=32)
    target_type: str = Field(..., pattern="^(seat|group|sector)$")
    target_ref: str = Field(..., min_length=1, max_length=128)
    amount: Decimal
    currency: str = Field(default="RUB", min_length=3, max_length=8)

    @field_validator("amount")
    @classmethod
    def validate_amount(cls, value: Decimal) -> Decimal:
        return _validate_decimal_amount(value)


class PriceRuleItem(BaseModel):
    price_rule_id: str
    scheme_id: str
    pricing_category_id: str | None
    target_type: str
    target_ref: str
    amount: Decimal | str
    currency: str
    created_at: str


class PriceRuleCreateResponse(BaseModel):
    price_rule_id: str
    scheme_id: str
    pricing_category_id: str | None
    target_type: str
    target_ref: str
    amount: Decimal
    currency: str


class PriceRuleUpdateResponse(BaseModel):
    price_rule_id: str
    scheme_id: str
    pricing_category_id: str | None
    target_type: str
    target_ref: str
    amount: Decimal
    currency: str


class EffectiveSeatPriceResponse(BaseModel):
    scheme_id: str
    scheme_version_id: str
    seat_id: str
    sector_id: str | None
    group_id: str | None
    matched_rule_level: str
    matched_target_ref: str
    pricing_category_id: str | None
    amount: Decimal | str
    currency: str


class SchemePricingResponse(BaseModel):
    categories: list[PricingCategoryItem]
    rules: list[PriceRuleItem]


class PricingBundleResponse(BaseModel):
    categories: list[PricingCategoryItem]
    rules: list[PriceRuleItem]