import { useState } from "react";
import { useTranslation } from "react-i18next";
import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import {
  ApiError,
  can,
  fetchRecycleBin,
  purgeRecycleItem,
  restoreRecycleItem,
  type RecycleBinItem,
  type RecycleKind,
  type SessionUser,
} from "./api.js";
import { qk } from "./lib/query.js";
import { formatRelativeDateTime } from "./lib/format.js";
import { Modal } from "./ui/Modal.js";

// Recycle bin — the way back from an accidental delete. Lists everything soft-deleted
// across users/roles/subscriptions/plans/tariffs; an admin can Restore (back to its
// catalog) or Purge (permanent). Items auto-purge after the retention window. Gated by
// recyclebin:* (read to view, update to restore, delete to purge). See
// apps/server/src/recycle-bin.ts, wiki/concepts/soft-delete.md.

const KIND_KEY: Record<RecycleKind, string> = {
  user: "recycleBin.kind.user",
  role: "recycleBin.kind.role",
  subscription: "recycleBin.kind.subscription",
  plan: "recycleBin.kind.plan",
  tariff: "recycleBin.kind.tariff",
};

export function RecycleBin({ user }: { user: SessionUser | null }) {
  const { t } = useTranslation();
  const qc = useQueryClient();
  const binQ = useQuery({ queryKey: qk.recycleBin, queryFn: fetchRecycleBin });

  const canRestore = can(user, "recyclebin:update");
  const canPurge = can(user, "recyclebin:delete");

  const [error, setError] = useState<string | null>(null);
  const [purging, setPurging] = useState<RecycleBinItem | null>(null);

  const onError = (e: unknown) => setError(e instanceof ApiError ? e.message : (e as Error).message);
  const invalidate = () => {
    void qc.invalidateQueries({ queryKey: qk.recycleBin });
    // A restore/purge can change any catalog — refresh the ones a restore touches.
    for (const key of [["users"], ["roles"], ["subscriptions"], ["subscription-plans"], ["tariff"]]) {
      void qc.invalidateQueries({ queryKey: key });
    }
  };

  const restoreM = useMutation({
    mutationFn: ({ kind, id }: { kind: RecycleKind; id: string }) => restoreRecycleItem(kind, id),
    onSuccess: invalidate,
    onError,
  });
  const purgeM = useMutation({
    mutationFn: ({ kind, id }: { kind: RecycleKind; id: string }) => purgeRecycleItem(kind, id),
    onSuccess: () => {
      setPurging(null);
      invalidate();
    },
    onError: (e) => {
      setPurging(null);
      onError(e);
    },
  });

  const items = binQ.data?.items ?? [];
  const retentionDays = binQ.data?.retentionDays ?? 0;

  return (
    <div className="mx-auto max-w-4xl">
      <div className="mb-3 flex items-center gap-3">
        <h1 className="text-base font-bold uppercase tracking-widest text-term-amber">
          {t("recycleBin.title")}
        </h1>
        {retentionDays > 0 && (
          <span className="text-[0.75rem] text-term-muted">
            {t("recycleBin.retentionNote", { days: retentionDays })}
          </span>
        )}
      </div>

      {error && <p className="mb-2 text-[0.75rem] text-term-red">{error}</p>}
      {binQ.isLoading && <p className="text-term-muted">{t("common.loading")}</p>}

      {!binQ.isLoading && items.length === 0 ? (
        <p className="rounded-term border border-term-border bg-term-panel p-6 text-center text-term-muted">
          {t("recycleBin.empty")}
        </p>
      ) : (
        <table className="w-full text-[0.8125rem]">
          <thead>
            <tr className="border-b border-term-border text-left text-[0.6875rem] uppercase tracking-wider text-term-muted">
              <th className="py-1.5 pr-3">{t("recycleBin.col.type")}</th>
              <th className="py-1.5 pr-3">{t("recycleBin.col.item")}</th>
              <th className="py-1.5 pr-3">{t("recycleBin.col.deleted")}</th>
              <th className="py-1.5 text-right">{t("recycleBin.col.actions")}</th>
            </tr>
          </thead>
          <tbody>
            {items.map((it) => (
              <tr key={`${it.kind}:${it.id}`} className="border-b border-term-border/50">
                <td className="py-1.5 pr-3">
                  <span className="rounded-term border border-term-border px-1.5 py-0.5 text-[0.6875rem] text-term-muted">
                    {t(KIND_KEY[it.kind])}
                  </span>
                </td>
                <td className="py-1.5 pr-3 text-term-text">{it.label}</td>
                <td className="py-1.5 pr-3 text-term-muted">
                  {formatRelativeDateTime(it.deletedAt, t)}
                </td>
                <td className="py-1.5 text-right">
                  {canRestore && (
                    <button
                      type="button"
                      className="btn btn-sm"
                      disabled={restoreM.isPending}
                      onClick={() => {
                        setError(null);
                        restoreM.mutate({ kind: it.kind, id: it.id });
                      }}
                    >
                      {t("recycleBin.restore")}
                    </button>
                  )}
                  {canPurge && (
                    <button
                      type="button"
                      className="btn btn-sm btn-ghost ml-1 text-term-red"
                      onClick={() => {
                        setError(null);
                        setPurging(it);
                      }}
                    >
                      {t("recycleBin.purge")}
                    </button>
                  )}
                </td>
              </tr>
            ))}
          </tbody>
        </table>
      )}

      {purging && (
        <Modal open onClose={() => setPurging(null)} title={t("recycleBin.purgeConfirmTitle")}>
          <p className="text-[0.8125rem] text-term-text">
            {t("recycleBin.purgeConfirmBody", { label: purging.label })}
          </p>
          <p className="mt-1 text-[0.75rem] text-term-red">{t("recycleBin.purgeIrreversible")}</p>
          <div className="mt-3 flex justify-end gap-2">
            <button type="button" className="btn btn-sm btn-ghost" onClick={() => setPurging(null)}>
              {t("common.cancel")}
            </button>
            <button
              type="button"
              className="btn btn-sm btn-danger"
              disabled={purgeM.isPending}
              onClick={() => purgeM.mutate({ kind: purging.kind, id: purging.id })}
            >
              {t("recycleBin.purge")}
            </button>
          </div>
        </Modal>
      )}
    </div>
  );
}