"""Admin: the feed settings and the VISUAL resource map. Every route needs the admin role and a password session.

A settings save NOTIFYs `ps_settings` so the worker reschedules at once. Resource map changes apply on the next
feed run. Every change is audited with before and after.
"""

from __future__ import annotations

from typing import Any

from fastapi import APIRouter, Body, Depends, Response
from psycopg.rows import dict_row
from pydantic import BaseModel, Field

from .. import audit
from ..domain.projects import Who
from ..feed import config
from .deps import Db, Principal, admin_principal, get_db
from .errors import ApiError
from .jobs import recent_runs
from .packets import WRITE

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

FEED_JOB = "visual-feed"
SPECIAL_TARGETS = ("fold", "ignore")
RESOURCE_MAX = 100


def _who(p: Principal) -> Who:
    return Who(user_id=p.user_id, session_id=p.session_id, role_snapshot=p.role_snapshot, ip=p.ip)


def _shop_codes(conn: Any) -> set[str]:
    rows = conn.execute("SELECT code FROM departments WHERE kind = 'shop' AND active").fetchall()
    return {r[0] for r in rows}


def _settings_out(conn: Any) -> dict[str, Any]:
    fs, version, updated_at, updated_by = config.load_versioned(conn)
    nxt = conn.execute("SELECT next_run_at FROM job_schedule WHERE job = %s", (FEED_JOB,)).fetchone()
    return {
        **fs.model_dump(mode="json"),
        "version": version,
        "updated_at": updated_at,
        "updated_by": str(updated_by) if updated_by else None,
        "next_run_at": nxt[0] if nxt else None,
        "runs": recent_runs(conn, FEED_JOB, 10),
    }


@router.get("/settings")
def get_settings(p: Principal = Depends(admin_principal), d: Db = Depends(get_db)) -> dict[str, Any]:  # noqa: B008
    return _settings_out(d.conn)


@router.patch("/settings", dependencies=WRITE)
def patch_settings(
    patch: dict[str, Any] = Body(...),  # noqa: B008
    p: Principal = Depends(admin_principal),  # noqa: B008
    d: Db = Depends(get_db),  # noqa: B008
) -> dict[str, Any]:
    conn = d.conn
    if "departments" in patch and isinstance(patch["departments"], list):
        shop = _shop_codes(conn)
        bad = sorted({str(x).strip() for x in patch["departments"]} - shop)
        if bad:
            raise ApiError(
                422,
                "bad_settings",
                f"Not an active shop department: {', '.join(bad)}.",
                extra={"errors": [f"departments: {b} is not an active shop department" for b in bad]},
            )
    try:
        config.save(conn, who=_who(p), patch=patch)
    except config.SettingsError as e:
        raise ApiError(422, "bad_settings", str(e), extra={"errors": e.errors}) from None
    return _settings_out(conn)


# ---------------------------------------------------------------- resource map


class MapBody(BaseModel):
    target: str = Field(max_length=20)
    confirmed: bool = True


def _resource(resource: str) -> str:
    r = resource.strip()
    if not r or len(r) > RESOURCE_MAX:
        raise ApiError(400, "bad_resource", "Give the VISUAL resource name.")
    return r


def _map_row(conn: Any, resource: str) -> dict[str, Any] | None:
    with conn.cursor(row_factory=dict_row) as cur:
        r = cur.execute(
            "SELECT resource, target, confirmed, updated_at, updated_by FROM visual_resource_map WHERE resource = %s",
            (resource,),
        ).fetchone()
    return dict(r) if r else None


def _row_out(r: dict[str, Any], rows_last_run: int | None) -> dict[str, Any]:
    return {
        "resource": r["resource"],
        "target": r.get("target"),
        "confirmed": bool(r.get("confirmed")),
        "rows_last_run": rows_last_run,
        "updated_at": r.get("updated_at"),
    }


def _last_counts(conn: Any) -> dict[str, int]:
    rows = conn.execute(
        "SELECT res, count(*) FROM visual_rows"
        " WHERE last_batch = (SELECT max(id) FROM visual_batches) AND res <> '' GROUP BY res"
    ).fetchall()
    return {r[0]: int(r[1]) for r in rows}


@router.get("/resource-map")
def resource_map(p: Principal = Depends(admin_principal), d: Db = Depends(get_db)) -> list[dict[str, Any]]:  # noqa: B008
    conn = d.conn
    counts = _last_counts(conn)
    with conn.cursor(row_factory=dict_row) as cur:
        mapped = cur.execute("SELECT resource, target, confirmed, updated_at FROM visual_resource_map").fetchall()
    out = {r["resource"]: _row_out(r, counts.get(r["resource"])) for r in mapped}
    for res, n in counts.items():
        if res not in out:
            out[res] = {"resource": res, "target": None, "confirmed": False, "rows_last_run": n, "updated_at": None}
    return sorted(out.values(), key=lambda r: (r["target"] is not None, r["resource"].lower()))


def _public(r: dict[str, Any] | None) -> dict[str, Any] | None:
    if r is None:
        return None
    return {"target": r["target"], "confirmed": r["confirmed"]}


@router.put("/resource-map/{resource}", dependencies=WRITE)
def map_resource(
    resource: str,
    body: MapBody,
    p: Principal = Depends(admin_principal),  # noqa: B008
    d: Db = Depends(get_db),  # noqa: B008
) -> dict[str, Any]:
    conn = d.conn
    res = _resource(resource)
    target = body.target.strip()
    if target.lower() in SPECIAL_TARGETS:
        target = target.lower()
    elif target not in _shop_codes(conn):
        raise ApiError(422, "bad_target", "The target is Fold, Ignore or an active shop department.")
    with conn.transaction():
        before = _map_row(conn, res)
        conn.execute(
            "INSERT INTO visual_resource_map (resource, target, confirmed, updated_at, updated_by)"
            " VALUES (%s, %s, %s, now(), %s) ON CONFLICT (resource) DO UPDATE SET target = EXCLUDED.target,"
            " confirmed = EXCLUDED.confirmed, updated_at = now(), updated_by = EXCLUDED.updated_by",
            (res, target, body.confirmed, p.user_id),
        )
        after = _map_row(conn, res)
        audit.append(
            conn,
            action="feed.resource_mapped",
            user_id=p.user_id,
            session_id=p.session_id,
            role_snapshot=p.role_snapshot,
            subject_type="visual_resource",
            subject_id=res,
            detail={"resource": res, "before": _public(before), "after": _public(after)},
            ip=p.ip,
        )
    assert after is not None
    return _row_out(after, _last_counts(conn).get(res))


@router.delete("/resource-map/{resource}", status_code=204, dependencies=WRITE)
def unmap_resource(
    resource: str,
    p: Principal = Depends(admin_principal),  # noqa: B008
    d: Db = Depends(get_db),  # noqa: B008
) -> Response:
    conn = d.conn
    res = _resource(resource)
    with conn.transaction():
        before = _map_row(conn, res)
        if before is None:
            raise ApiError(404, "not_found", "That resource is not mapped.")
        conn.execute("DELETE FROM visual_resource_map WHERE resource = %s", (res,))
        audit.append(
            conn,
            action="feed.resource_unmapped",
            user_id=p.user_id,
            session_id=p.session_id,
            role_snapshot=p.role_snapshot,
            subject_type="visual_resource",
            subject_id=res,
            detail={"resource": res, "before": _public(before), "after": None},
            ip=p.ip,
        )
    return Response(status_code=204)