"""Change-proposal endpoints: list / create / get / apply / reject / delete.

Applying a proposal is the only way its operations reach the database, and only
an editor can do it (enforced in the service). See docs/design/change-proposal.md.
"""

import uuid

from fastapi import APIRouter, status

from app.api.deps import CurrentUser, SessionDep
from app.models.enums import ChangeProposalStatus
from app.schemas.change_proposal import (
    ChangeProposalCreate,
    ChangeProposalRead,
    ProposalReview,
)
from app.services import change_proposal_service, tree_service

router = APIRouter(prefix="/trees", tags=["proposals"])


@router.get("/{tree_id}/proposals", response_model=list[ChangeProposalRead])
async def list_proposals(
    tree_id: uuid.UUID,
    session: SessionDep,
    current: CurrentUser,
    status: ChangeProposalStatus | None = None,
) -> list[ChangeProposalRead]:
    tree = await tree_service.get_tree(session, viewer_id=current.id, tree_id=tree_id)
    rows = await change_proposal_service.list_proposals(
        session, viewer_id=current.id, tree=tree, status=status
    )
    return [ChangeProposalRead.model_validate(r) for r in rows]


@router.post(
    "/{tree_id}/proposals", response_model=ChangeProposalRead, status_code=status.HTTP_201_CREATED
)
async def create_proposal(
    tree_id: uuid.UUID, data: ChangeProposalCreate, session: SessionDep, current: CurrentUser
) -> ChangeProposalRead:
    tree = await tree_service.get_tree(session, viewer_id=current.id, tree_id=tree_id)
    operations = [op.model_dump(mode="json") for op in data.operations]
    cp = await change_proposal_service.propose(
        session,
        tree=tree,
        origin=data.origin,
        created_by=current.id,
        summary=data.summary,
        rationale=data.rationale,
        operations=operations,
    )
    return ChangeProposalRead.model_validate(cp)


@router.get("/{tree_id}/proposals/{proposal_id}", response_model=ChangeProposalRead)
async def get_proposal(
    tree_id: uuid.UUID, proposal_id: uuid.UUID, session: SessionDep, current: CurrentUser
) -> ChangeProposalRead:
    tree = await tree_service.get_tree(session, viewer_id=current.id, tree_id=tree_id)
    cp = await change_proposal_service.get_proposal(
        session, viewer_id=current.id, tree=tree, proposal_id=proposal_id
    )
    return ChangeProposalRead.model_validate(cp)


@router.post("/{tree_id}/proposals/{proposal_id}/apply", response_model=ChangeProposalRead)
async def apply_proposal(
    tree_id: uuid.UUID,
    proposal_id: uuid.UUID,
    session: SessionDep,
    current: CurrentUser,
    data: ProposalReview | None = None,
) -> ChangeProposalRead:
    tree = await tree_service.get_tree(session, viewer_id=current.id, tree_id=tree_id)
    edited = (
        [op.model_dump(mode="json") for op in data.operations]
        if data and data.operations is not None
        else None
    )
    cp = await change_proposal_service.apply(
        session, actor=current, tree=tree, proposal_id=proposal_id, edited_operations=edited
    )
    return ChangeProposalRead.model_validate(cp)


@router.post("/{tree_id}/proposals/{proposal_id}/reject", response_model=ChangeProposalRead)
async def reject_proposal(
    tree_id: uuid.UUID,
    proposal_id: uuid.UUID,
    session: SessionDep,
    current: CurrentUser,
    data: ProposalReview | None = None,
) -> ChangeProposalRead:
    tree = await tree_service.get_tree(session, viewer_id=current.id, tree_id=tree_id)
    cp = await change_proposal_service.reject(
        session,
        actor=current,
        tree=tree,
        proposal_id=proposal_id,
        note=data.note if data else None,
    )
    return ChangeProposalRead.model_validate(cp)


@router.delete(
    "/{tree_id}/proposals/{proposal_id}", status_code=status.HTTP_204_NO_CONTENT
)
async def delete_proposal(
    tree_id: uuid.UUID, proposal_id: uuid.UUID, session: SessionDep, current: CurrentUser
) -> None:
    tree = await tree_service.get_tree(session, viewer_id=current.id, tree_id=tree_id)
    await change_proposal_service.delete_proposal(
        session, actor=current, tree=tree, proposal_id=proposal_id
    )