"""The Q.C. screen: the home board and the project and unit folders with their documents.

Any signed-in session reads. Filing a folder document is QC_DOC_ADD (Clerical or Q.C.; admin with an IT reason),
decided by policy.engine.check_scoped because a folder belongs to a project or a unit, not a packet. Screens read
PostgreSQL only.
"""

from __future__ import annotations

import uuid
from typing import Any

from fastapi import APIRouter, Depends, Query, Request
from pydantic import BaseModel, Field

from .. import audit, events, policy
from ..domain import assets as asset_store
from ..domain import itp as itp_dom
from ..domain import packets, qcdocs, search
from ..domain import qc as dom
from ..text import clean_opt, clean_text
from .deps import Db, Principal, current_principal, get_db
from .errors import ApiError
from .packets import FIND, WRITE, site_today

router = APIRouter(prefix="/api/qc", tags=["qc"])

A = policy.Action


class QcDocBody(BaseModel):
    project_id: int | None = None
    unit_id: int | None = None
    type: str = Field(min_length=1, max_length=100)
    title: str | None = Field(default=None, max_length=1000)
    rev: str | None = Field(default=None, max_length=100)
    note: str | None = Field(default=None, max_length=5000)
    asset_id: uuid.UUID
    replaces: int | None = None
    it_reason: str | None = Field(default=None, max_length=1000)


@router.get("/home")
def home(
    request: Request,
    p: Principal = Depends(current_principal),  # noqa: B008
    d: Db = Depends(get_db),  # noqa: B008
    find: dict[str, Any] = FIND,
    project_id: int | None = Query(None),
    unit_id: int | None = Query(None),
) -> dict[str, Any]:
    """The Q.C. home. The find bar values narrow the cards of the three boards; the KPIs follow the project and
    unit only."""
    conn = d.conn
    pp = packets.policy_principal_for(conn, p)
    filters = search.parse_filters(
        {**find, "project_id": project_id, "unit_id": unit_id}, pp, screen="qc", today=site_today(request)
    )
    return dom.home(conn, pp, project_id=project_id, unit_id=unit_id, filters=filters)


@router.get("/folders")
def folders(
    p: Principal = Depends(current_principal),  # noqa: B008
    d: Db = Depends(get_db),  # noqa: B008
    show: str = Query("active", pattern="^(active|all)$"),
) -> list[dict[str, Any]]:
    return qcdocs.folders(d.conn, show)


@router.get("/folders/projects/{project_id}")
def project_folder(
    project_id: int,
    p: Principal = Depends(current_principal),  # noqa: B008
    d: Db = Depends(get_db),  # noqa: B008
) -> dict[str, Any]:
    out = qcdocs.project_folder(d.conn, project_id)
    if out is None:
        raise ApiError(404, "not_found", "No such project.")
    return out


@router.get("/folders/units/{unit_id}")
def unit_folder(
    unit_id: int,
    p: Principal = Depends(current_principal),  # noqa: B008
    d: Db = Depends(get_db),  # noqa: B008
) -> dict[str, Any]:
    out = qcdocs.unit_folder(d.conn, unit_id)
    if out is None:
        raise ApiError(404, "not_found", "No such unit.")
    return out


@router.post("/docs", dependencies=WRITE)
def add_doc(
    body: QcDocBody,
    p: Principal = Depends(current_principal),  # noqa: B008
    d: Db = Depends(get_db),  # noqa: B008
) -> dict[str, Any]:
    """File a document in a project or unit folder, or a new revision of one (`replaces`). Nothing is deleted: the
    old revision points at the new one. The answer is the folder read."""
    conn = d.conn
    if (body.project_id is None) == (body.unit_id is None):
        raise ApiError(422, "invalid_request", "File the document in one project or one unit.")
    doc_type = clean_text(body.type, 100)
    if doc_type not in qcdocs.QC_TYPES:
        raise ApiError(422, "invalid_type", "Pick a document type from the list.")
    asset = asset_store.get(conn, body.asset_id)
    if asset is None:
        raise ApiError(404, "not_found", "No such file.")
    if asset["mime"] not in qcdocs.DOC_MIMES:
        raise ApiError(422, "invalid_asset", "The file must be a PDF, PNG or JPEG.")
    title = clean_opt(body.title, qcdocs.TITLE_MAX) or doc_type
    rev = clean_opt(body.rev, qcdocs.REV_MAX)
    note = clean_opt(body.note, qcdocs.NOTE_MAX)
    pp = packets.policy_principal_for(conn, p)
    decision, it_kept = itp_dom.scoped_decision(p, pp, A.QC_DOC_ADD, it_reason=body.it_reason)
    with conn.transaction():
        if body.unit_id is not None:
            folder = packets.one(
                conn,
                "SELECT u.id, pr.number || u.lot AS number FROM units u JOIN projects pr ON pr.id = u.project_id"
                " WHERE u.id = %s AND u.removed_at IS NULL FOR UPDATE OF u",
                (body.unit_id,),
            )
            scope_col = "unit_id"
        else:
            folder = packets.one(
                conn,
                "SELECT id, number FROM projects WHERE id = %s AND removed_at IS NULL FOR UPDATE",
                (body.project_id,),
            )
            scope_col = "project_id"
        if folder is None:
            raise ApiError(404, "not_found", "No such unit." if body.unit_id is not None else "No such project.")
        old = None
        if body.replaces is not None:
            old = packets.one(conn, "SELECT * FROM qc_docs WHERE id = %s FOR UPDATE", (body.replaces,))
            if old is None or old[scope_col] != folder["id"]:
                raise ApiError(422, "invalid_replace", "That document is not in this folder.")
            if old["superseded_by"] is not None:
                raise ApiError(409, "already_superseded", "That document already has a newer revision.")
        new_id = int(
            conn.execute(
                "INSERT INTO qc_docs (project_id, unit_id, type, title, rev, note, asset_id, added_by)"
                " VALUES (%s, %s, %s, %s, %s, %s, %s, %s) RETURNING id",
                (body.project_id, body.unit_id, doc_type, title, rev, note, asset["id"], p.user_id),
            ).fetchone()[0]
        )
        if old is not None:
            conn.execute(
                "UPDATE qc_docs SET superseded_by = %s, superseded_at = now(), superseded_by_user = %s WHERE id = %s",
                (new_id, p.user_id, old["id"]),
            )
        title_rev = f"{title} Rev {rev}" if rev else title
        text_note = " · ".join(x for x in (folder["number"], doc_type, title_rev, asset.get("original_name")) if x)
        revise = old is not None
        detail: dict[str, Any] = {
            "text": "Q.C. document revised" if revise else "Q.C. document added",
            "note": text_note,
            "doc_id": new_id,
            "project_id": body.project_id,
            "unit_id": body.unit_id,
        }
        if revise:
            detail["replaces"] = old["id"] if old else None
        audit.append(
            conn,
            action="qc_doc.revise" if revise else "qc_doc.add",
            user_id=p.user_id,
            session_id=p.session_id,
            role_snapshot=p.role_snapshot,
            subject_type="qc_doc",
            subject_id=new_id,
            detail=detail,
            it_reason=it_kept,
            ip=p.ip,
        )
        events.publish(
            conn,
            {"event": "changed", "kind": "qc_doc", "project_id": body.project_id, "unit_id": body.unit_id},
        )
    del decision
    if body.unit_id is not None:
        out = qcdocs.unit_folder(conn, body.unit_id)
    else:
        assert body.project_id is not None
        out = qcdocs.project_folder(conn, body.project_id)
    assert out is not None
    return out