from __future__ import annotations

from dataclasses import dataclass, field
from datetime import datetime
from decimal import Decimal
from typing import Any
from uuid import UUID

from app.domain.enums import (
    Availability,
    ConstraintOperator,
    Eligibility,
    NormalizationStatus,
    OfferCondition,
    PreferenceDirection,
    PreferenceStrategy,
    PriceBasis,
    PriceReferenceScope,
    ValueType,
)


@dataclass(frozen=True)
class Budget:
    target: Decimal
    maximum: Decimal


@dataclass(frozen=True)
class Constraint:
    id: str
    attribute: str
    operator: ConstraintOperator
    value: Any = None
    mandatory: bool = True


@dataclass(frozen=True)
class Preference:
    id: str
    attribute: str
    strategy: PreferenceStrategy
    direction: PreferenceDirection
    acceptable: Decimal
    ideal: Decimal
    weight: Decimal


@dataclass(frozen=True)
class ClassificationBound:
    upper: Decimal
    inclusive: bool
    label: str


@dataclass(frozen=True)
class ScoringModel:
    version: str
    algorithm_id: str
    supported_preference_strategies: tuple[str, ...]
    minimum_confidence: Decimal
    maximum_price_age_hours: int
    optional_constraint_penalty_points: Decimal
    missing_preference_score: Decimal
    product_weight: Decimal
    price_weight: Decimal
    budget_weight: Decimal
    history_weight: Decimal
    history_window_days: int
    minimum_history_days: int
    history_discount_for_max_score: Decimal
    classification_upper_bounds: tuple[ClassificationBound, ...]
    definition: dict[str, Any]
    definition_hash: str


@dataclass(frozen=True)
class Profile:
    id: str
    version: int
    name: str
    category: str
    currency: str
    market: str
    allowed_conditions: tuple[OfferCondition, ...]
    budget: Budget
    scoring_version: str
    constraints: tuple[Constraint, ...]
    preferences: tuple[Preference, ...]
    definition: dict[str, Any]
    definition_hash: str


@dataclass(frozen=True)
class AttributeDefinition:
    key: str
    value_type: ValueType
    canonical_unit: str | None
    minimum: Decimal | None
    maximum: Decimal | None
    description: str | None


@dataclass(frozen=True)
class Product:
    id: UUID
    category: str
    brand: str
    name: str
    model: str | None
    created_at: datetime


@dataclass(frozen=True)
class ProductVariant:
    id: UUID
    product_id: UUID
    name: str
    manufacturer_sku: str | None
    identifiers: dict[str, Any]
    created_at: datetime


@dataclass(frozen=True)
class AttributeStatement:
    id: UUID
    variant_id: UUID
    attribute: str
    raw_value: Any
    normalized_value: Any
    unit: str | None
    normalization_status: NormalizationStatus
    normalizer_version: str
    confidence: Decimal
    source_id: str
    source_reference: str
    observed_at: datetime
    ingested_at: datetime
    normalization_error: str | None = None


@dataclass(frozen=True)
class Offer:
    id: UUID
    variant_id: UUID
    source_id: str
    external_id: str
    seller: str
    url: str | None
    market: str
    currency: str
    condition: OfferCondition
    created_at: datetime


@dataclass(frozen=True)
class PriceObservation:
    id: UUID
    offer_id: UUID
    source_id: str
    external_observation_id: str
    observed_at: datetime
    ingested_at: datetime
    item_price: Decimal
    shipping_price: Decimal | None
    currency: str
    availability: Availability
    raw_payload: Any
    confidence: Decimal

    @property
    def total_price(self) -> Decimal | None:
        if self.shipping_price is None:
            return None
        return self.item_price + self.shipping_price


@dataclass(frozen=True)
class ConstraintResult:
    constraint_id: str
    attribute: str
    operator: str
    expected: Any
    actual: Any
    status: str
    mandatory: bool
    attribute_row_id: UUID | None
    reason_code: str


@dataclass(frozen=True)
class GateResult:
    key: str
    status: str
    reason_code: str
    details: dict[str, Any] = field(default_factory=dict)


@dataclass(frozen=True)
class ScoreComponent:
    kind: str
    component_key: str
    raw_score: Decimal | None
    weight: Decimal | None
    contribution: Decimal | None
    details: dict[str, Any]


@dataclass(frozen=True)
class HistoryWindow:
    days: int
    values: tuple[Decimal, ...]
    observation_ids: tuple[UUID, ...]

    @property
    def day_count(self) -> int:
        return len(self.values)


@dataclass(frozen=True)
class PriceStatistics:
    current_total: Decimal | None
    median_30d: Decimal | None
    median_30d_days: int
    median_90d: Decimal | None
    median_90d_days: int
    lowest_365d: Decimal | None
    lowest_365d_days: int
    lowest_365d_is_full_year: bool
    used_observation_ids: tuple[UUID, ...]
    current_observation_id: UUID | None
    price_reference_scope: PriceReferenceScope = PriceReferenceScope.OFFER


@dataclass(frozen=True)
class Reason:
    code: str
    message: str


@dataclass(frozen=True)
class EvaluationResult:
    profile_id: str
    profile_version: int
    scoring_version: str
    scoring_hash: str
    engine_build: str
    variant_id: UUID
    offer_id: UUID
    as_of: datetime
    snapshot_cutoff: datetime
    product_eligibility: Eligibility
    offer_eligibility: Eligibility
    overall_eligibility: Eligibility
    eligible: bool | None
    product_score: Decimal | None
    product_score_raw: Decimal | None
    price_score: Decimal | None
    price_score_raw: Decimal | None
    deal_score: Decimal | None
    deal_score_raw: Decimal | None
    classification: str
    price_basis: PriceBasis | None
    product_coverage: Decimal
    constraint_results: tuple[ConstraintResult, ...]
    product_gates: tuple[GateResult, ...]
    offer_gates: tuple[GateResult, ...]
    components: tuple[ScoreComponent, ...]
    price_statistics: PriceStatistics
    price_reference_scope: PriceReferenceScope
    reasons: tuple[Reason, ...]
    warnings: tuple[str, ...]
    input_snapshot: dict[str, Any]
    failed_constraints: tuple[ConstraintResult, ...]
    unknown_constraints: tuple[ConstraintResult, ...]