from decimal import Decimal
from typing import Annotated, Literal

from pydantic import BaseModel, Field, field_validator

from app.domain import REOPEN_TARGET_STAGES, Stage
from app.schemas.common import AppModel, UTCDateTime
from app.schemas.user import UserRef

Money = Annotated[Decimal, Field(ge=0, max_digits=12, decimal_places=2)]


# ── Inputs ───────────────────────────────────────────────────────────────────
class NcrCreateIn(BaseModel):
    job_number: str = Field(min_length=1, max_length=100)
    department_id: int
    deviation_category_id: int
    disposition_authority_id: int
    deviation_detail: str = Field(min_length=5, max_length=20000)


class InitialDispositionIn(BaseModel):
    qc_authority: str | None = Field(default=None, max_length=255)
    work_order: str | None = Field(default=None, max_length=100)
    disposition_notes: str | None = Field(default=None, max_length=100000)
    secondary_review_needed: bool
    # "Notify These People" — required when secondary_review_needed is true.
    secondary_authority_ids: list[int] = []


class SecondaryDispositionIn(BaseModel):
    qc_authority: str | None = Field(default=None, max_length=255)
    work_order: str | None = Field(default=None, max_length=100)
    disposition_notes: str | None = Field(default=None, max_length=100000)
    # False = save updates and keep in my queue; True = release to Operations.
    release: bool = False


class InspectionIn(BaseModel):
    qc_approval: Literal["yes", "no"] | None = None
    inspection_notes: str | None = Field(default=None, max_length=20000)
    # False = save and revisit later; True = advance to Costing.
    qc_closed: bool = False


class CostingIn(BaseModel):
    labor_cost: Money
    material_cost: Money
    service_cost: Money
    other_cost: Money


class ReopenIn(BaseModel):
    to_stage: Stage
    reason: str = Field(min_length=5, max_length=2000)

    @field_validator("to_stage")
    @classmethod
    def _valid_target(cls, v: Stage) -> Stage:
        if v not in REOPEN_TARGET_STAGES:
            raise ValueError("Reopen target must be a prior (non-closed) stage.")
        return v


# ── Outputs ──────────────────────────────────────────────────────────────────
class AttachmentOut(AppModel):
    id: int
    original_filename: str
    content_type: str
    size_bytes: int
    is_image: bool
    uploaded_at: UTCDateTime
    uploaded_by: UserRef


class TransitionOut(AppModel):
    id: int
    from_stage: str | None
    to_stage: str
    action: str
    acted_at: UTCDateTime
    acted_by: UserRef
    note: str | None


class JobInfoOut(AppModel):
    part_id: str | None
    part_description: str | None
    customer_name: str | None
    work_order_status: str | None
    source: str


class NcrListItem(BaseModel):
    id: int
    ncr_number: str
    job_number: str
    department: str
    deviation_category: str
    requester: str
    disposition_authority: str
    stage: str
    stage_label: str
    days_in_stage: int
    created_at: UTCDateTime


class NcrListOut(BaseModel):
    items: list[NcrListItem]
    total: int
    page: int
    page_size: int


class NcrDetailOut(BaseModel):
    id: int
    ncr_number: str
    job_number: str
    created_at: UTCDateTime
    stage: str
    stage_label: str
    stage_entered_at: UTCDateTime
    days_in_stage: int

    department: str
    department_id: int
    deviation_category: str
    deviation_category_id: int
    deviation_detail: str
    requester: UserRef
    disposition_authority: UserRef

    qc_authority: str | None
    work_order: str | None
    disposition_notes: str | None
    secondary_review_needed: bool | None
    secondary_authorities: list[UserRef]

    operations_complete: bool
    operations_completed_at: UTCDateTime | None
    operations_completed_by: UserRef | None

    qc_approval: str | None
    inspection_notes: str | None
    qc_closed: bool
    qc_closed_at: UTCDateTime | None
    qc_closed_by: UserRef | None

    labor_cost: Decimal | None
    material_cost: Decimal | None
    service_cost: Decimal | None
    other_cost: Decimal | None
    total_cost: Decimal | None
    costing_completed_at: UTCDateTime | None
    costing_completed_by: UserRef | None

    closed_at: UTCDateTime | None
    closed_by: UserRef | None

    job_info: JobInfoOut | None
    attachments: list[AttachmentOut]
    transitions: list[TransitionOut]

    # Actions the *current* user may take right now (informs the UI; the API
    # re-enforces every one of these server-side).
    available_actions: list[str]


class NcrMutationOut(BaseModel):
    ncr: NcrDetailOut
    warnings: list[str] = []


class AuditEntryOut(AppModel):
    id: int
    created_at: UTCDateTime
    user: UserRef
    action: str
    field_name: str | None
    old_value: str | None
    new_value: str | None
    detail: str | None


class AuditListOut(BaseModel):
    items: list[AuditEntryOut]
    total: int