"""HTTP boundary for G2 educational longitudinal outcome trajectories."""

from __future__ import annotations

from datetime import datetime
from typing import Annotated, Literal
from uuid import UUID

from fastapi import APIRouter, Depends, HTTPException, status
from pydantic import BaseModel, ConfigDict, Field, field_validator, model_validator

from ..contracts.measurement import MeasurementPerspective, SourceKind
from ..contracts.outcome_trajectory import (
    LongitudinalOutcomeAssessment,
    OutcomeAxis,
    RelationshipEventType,
    RelationshipMemoryProjection,
    SafetySignalReference,
    SyntheticExpectedDistribution,
)
from ..deps import CurrentPrincipal, Principal, Role, require_role
from ..services import feedback_policy, outcome_trajectory_store


router = APIRouter(prefix="/sessions", tags=["outcome-trajectories"])
LearnerPrincipal = Annotated[Principal, Depends(require_role(Role.LEARNER))]
TeacherPrincipal = Annotated[
    Principal,
    Depends(require_role(Role.TEACHER, Role.ADMIN)),
]


class ExpectedArcLabelResponse(BaseModel):
    schema_version: Literal["vignette.synthetic-outcome-arc.v1"]
    arc_id: str
    title_ko: str
    data_classification: Literal["synthetic_educational"]
    clinical_claim_allowed: Literal[False]
    provenance_note: str
    session_count: Literal[5] = 5
    distributions: list[SyntheticExpectedDistribution] = Field(
        min_length=15, max_length=15
    )


class OutcomeObservationResponse(BaseModel):
    model_config = ConfigDict(protected_namespaces=())

    measurement_id: UUID | None = None
    session_id: UUID
    session_no: int = Field(ge=1, le=5)
    axis: OutcomeAxis
    status: Literal["observed", "missing", "error"]
    value: float | None = Field(default=None, ge=0.0, le=1.0)
    raw_value: float | None = None
    scale_min: float | None = None
    scale_max: float | None = None
    confidence: float | None = Field(default=None, ge=0.0, le=1.0)
    source_kind: SourceKind
    perspective: MeasurementPerspective
    instrument_id: str
    instrument_version: str
    model_run_id: UUID | None = None
    evidence_refs: list[str] = Field(default_factory=list)
    missing_reason: str | None = None
    occurred_at: datetime | None = None


class OutcomeTrajectoryResponse(BaseModel):
    session_id: UUID
    revision_id: UUID
    revision_no: int = Field(ge=1)
    supersedes_revision_id: UUID | None = None
    source_fingerprint: str = Field(pattern=r"^[a-f0-9]{64}$")
    recompute_reason: str
    computed_at: datetime
    notice_ko: str
    expected_arc: ExpectedArcLabelResponse
    assessment: LongitudinalOutcomeAssessment
    next_questions: list[str] = Field(default_factory=list)
    observations: list[OutcomeObservationResponse]
    safety_signals: list[SafetySignalReference] = Field(default_factory=list)
    relationship_memory: list[RelationshipMemoryProjection] = Field(
        default_factory=list
    )


class OutcomeTrajectoryRecomputeRequest(BaseModel):
    reason: str = Field(default="manual_recompute", min_length=1, max_length=300)

    @field_validator("reason")
    @classmethod
    def strip_reason(cls, value: str) -> str:
        stripped = value.strip()
        if not stripped:
            raise ValueError("reason must not be blank")
        return stripped


class OutcomeAxisValues(BaseModel):
    model_config = ConfigDict(extra="forbid")

    distress_load: float = Field(ge=0.0, le=1.0)
    daily_functioning: float = Field(ge=0.0, le=1.0)
    learning_engagement: float = Field(ge=0.0, le=1.0)


class OutcomeObservationSubmissionRequest(BaseModel):
    model_config = ConfigDict(extra="forbid")

    submission_id: UUID
    scores: OutcomeAxisValues
    confidences: OutcomeAxisValues
    evidence_turn_ids: tuple[UUID, ...] = Field(default=(), max_length=12)

    @field_validator("evidence_turn_ids")
    @classmethod
    def unique_evidence_turns(cls, value: tuple[UUID, ...]) -> tuple[UUID, ...]:
        if len(set(value)) != len(value):
            raise ValueError("evidence_turn_ids must be unique")
        return value


class OutcomeObservationSubmissionResponse(OutcomeTrajectoryResponse):
    submission_id: UUID
    submitted_measurement_ids: list[UUID] = Field(min_length=3, max_length=3)


RelationshipView = Literal[
    "client", "counselor", "evaluator", "supervisor", "research"
]


class RelationshipMemoryCreateRequest(BaseModel):
    model_config = ConfigDict(extra="forbid")

    event_type: RelationshipEventType
    summaries: dict[RelationshipView, str] = Field(min_length=1, max_length=5)
    evidence_turn_ids: tuple[UUID, ...] = Field(min_length=1, max_length=12)
    resolves_event_id: UUID | None = None

    @field_validator("summaries")
    @classmethod
    def normalize_summaries(
        cls, value: dict[RelationshipView, str]
    ) -> dict[RelationshipView, str]:
        normalized = {view: summary.strip() for view, summary in value.items()}
        if any(not summary for summary in normalized.values()):
            raise ValueError("relationship summaries must not be blank")
        return normalized

    @field_validator("evidence_turn_ids")
    @classmethod
    def unique_relationship_evidence(
        cls, value: tuple[UUID, ...]
    ) -> tuple[UUID, ...]:
        if len(set(value)) != len(value):
            raise ValueError("evidence_turn_ids must be unique")
        return value

    @model_validator(mode="after")
    def require_explicit_repair_target(self) -> "RelationshipMemoryCreateRequest":
        if self.event_type == "repair_confirmed" and self.resolves_event_id is None:
            raise ValueError("repair_confirmed requires resolves_event_id")
        if self.event_type != "repair_confirmed" and self.resolves_event_id is not None:
            raise ValueError("only repair_confirmed can resolve a relationship event")
        return self


class RelationshipMemoryCreateResponse(BaseModel):
    memory_event_id: UUID
    status: Literal["recorded"] = "recorded"


def _http_error(exc: Exception) -> HTTPException:
    if isinstance(exc, outcome_trajectory_store.OutcomeTrajectoryNotFoundError):
        return HTTPException(status.HTTP_404_NOT_FOUND, detail=str(exc))
    if isinstance(exc, outcome_trajectory_store.OutcomeTrajectoryConflictError):
        return HTTPException(status.HTTP_409_CONFLICT, detail=str(exc))
    if isinstance(exc, outcome_trajectory_store.OutcomeTrajectoryStateError):
        return HTTPException(status.HTTP_422_UNPROCESSABLE_ENTITY, detail=str(exc))
    raise exc


@router.get(
    "/{session_id}/outcome-trajectory",
    response_model=OutcomeTrajectoryResponse,
)
async def get_outcome_trajectory(
    session_id: UUID,
    principal: CurrentPrincipal,
) -> OutcomeTrajectoryResponse:
    await feedback_policy.require_session_learner_feedback(session_id, principal)
    try:
        payload = await outcome_trajectory_store.read_outcome_trajectory(
            principal=principal,
            session_id=session_id,
        )
    except (
        outcome_trajectory_store.OutcomeTrajectoryNotFoundError,
        outcome_trajectory_store.OutcomeTrajectoryConflictError,
        outcome_trajectory_store.OutcomeTrajectoryStateError,
    ) as exc:
        raise _http_error(exc) from exc
    return OutcomeTrajectoryResponse.model_validate(payload)


@router.post(
    "/{session_id}/outcome-trajectory/recompute",
    response_model=OutcomeTrajectoryResponse,
    status_code=status.HTTP_201_CREATED,
)
async def recompute_outcome_trajectory(
    session_id: UUID,
    body: OutcomeTrajectoryRecomputeRequest,
    principal: CurrentPrincipal,
) -> OutcomeTrajectoryResponse:
    await feedback_policy.require_session_learner_feedback(session_id, principal)
    try:
        payload = await outcome_trajectory_store.read_outcome_trajectory(
            principal=principal,
            session_id=session_id,
            force_recompute=True,
            recompute_reason=body.reason,
        )
    except (
        outcome_trajectory_store.OutcomeTrajectoryNotFoundError,
        outcome_trajectory_store.OutcomeTrajectoryConflictError,
        outcome_trajectory_store.OutcomeTrajectoryStateError,
    ) as exc:
        raise _http_error(exc) from exc
    return OutcomeTrajectoryResponse.model_validate(payload)


@router.post(
    "/{session_id}/outcome-observations",
    response_model=OutcomeObservationSubmissionResponse,
    status_code=status.HTTP_201_CREATED,
)
async def create_outcome_observations(
    session_id: UUID,
    body: OutcomeObservationSubmissionRequest,
    principal: LearnerPrincipal,
) -> OutcomeObservationSubmissionResponse:
    try:
        payload = await outcome_trajectory_store.submit_outcome_observations(
            principal=principal,
            session_id=session_id,
            submission_id=body.submission_id,
            scores=body.scores.model_dump(),
            confidences=body.confidences.model_dump(),
            evidence_turn_ids=body.evidence_turn_ids,
        )
    except (
        outcome_trajectory_store.OutcomeTrajectoryNotFoundError,
        outcome_trajectory_store.OutcomeTrajectoryConflictError,
        outcome_trajectory_store.OutcomeTrajectoryStateError,
    ) as exc:
        raise _http_error(exc) from exc
    return OutcomeObservationSubmissionResponse.model_validate(payload)


@router.post(
    "/{session_id}/relationship-memory-events",
    response_model=RelationshipMemoryCreateResponse,
    status_code=status.HTTP_201_CREATED,
)
async def create_relationship_memory_event(
    session_id: UUID,
    body: RelationshipMemoryCreateRequest,
    principal: TeacherPrincipal,
) -> RelationshipMemoryCreateResponse:
    try:
        memory_event_id = (
            await outcome_trajectory_store.append_relationship_memory_event(
                principal=principal,
                session_id=session_id,
                event_type=body.event_type,
                summaries=body.summaries,
                evidence_turn_ids=body.evidence_turn_ids,
                resolves_event_id=body.resolves_event_id,
            )
        )
    except (
        outcome_trajectory_store.OutcomeTrajectoryNotFoundError,
        outcome_trajectory_store.OutcomeTrajectoryConflictError,
        outcome_trajectory_store.OutcomeTrajectoryStateError,
    ) as exc:
        raise _http_error(exc) from exc
    return RelationshipMemoryCreateResponse(memory_event_id=memory_event_id)


__all__ = ["router"]