"use client";

import { useMemo } from "react";

import { useQuery } from "convex/react";
import { FunctionReturnType } from "convex/server";
import { Activity, Files, SquarePen } from "lucide-react";
import Link from "next/link";

import { api } from "@/convex/_generated/api";
import { Skeleton } from "@/components/ui/skeleton";
import { Badge } from "@/components/ui/badge";

type AuditDashboardRowsResult = FunctionReturnType<typeof api.audits.listDashboardRows>;
type AuditRow = Extract<NonNullable<AuditDashboardRowsResult>[number], { kind: "audit" }>;
type AuditDashboardRow = NonNullable<AuditDashboardRowsResult>[number];

const statusText: Record<string, string> = {
  draft: "Entwurf",
  approved: "Freigegeben",
  published: "Veröffentlicht",
  deactivated: "Deaktiviert",
};

const fallbackStatus = "Unbekannt";

const generationStageText: Record<string, string> = {
  audit_generation: "Audit-Generierung",
  classification: "Klassifikation",
  multimodalAudit: "Multimodale Analyse",
  germanCopy: "Deutsche Texte",
  qualityReview: "Qualitätsprüfung",
};

function formatPageCount(pageCount: number) {
  return `${pageCount} Seite${pageCount === 1 ? "" : "n"}`;
}

function getStatusLabel(status: AuditRow["status"]) {
  return statusText[status] ?? fallbackStatus;
}

function getGenerationStatusLabel(
  row: Extract<AuditDashboardRow, { kind: "generation" }>,
) {
  if (row.status === "pending") {
    return "Wartet auf Start";
  }

  if (row.status === "failed") {
    return "Fehlgeschlagen";
  }

  if (row.status === "canceled") {
    return "Abgebrochen";
  }

  if (row.status === "succeeded") {
    return "Wartet auf finales Audit";
  }

  return "Generierung läuft";
}

function getStageLabel(stage: string) {
  return generationStageText[stage] ?? stage;
}

function AuditsBoardLoading() {
  return (
    <section className="space-y-4">
      <header className="space-y-2">
        <p className="text-sm text-muted-foreground">Interne Audit-Übersicht</p>
        <h1 className="text-2xl font-semibold tracking-normal">Audits</h1>
        <p className="text-sm text-muted-foreground">Audits werden geladen...</p>
      </header>
      <div className="rounded-lg border">
        <div className="grid gap-2 p-3">
          {Array.from({ length: 4 }, (_, index) => (
            <Skeleton className="h-20 rounded-md" key={index} />
          ))}
        </div>
      </div>
    </section>
  );
}

export function AuditsBoard() {
  const dashboardRows = useQuery(api.audits.listDashboardRows, { limit: 100 });
  const rows = useMemo(() => {
    if (!dashboardRows) {
      return [];
    }

    return [...dashboardRows].sort((a, b) => b.updatedAt - a.updatedAt);
  }, [dashboardRows]);

  if (dashboardRows === undefined) {
    return <AuditsBoardLoading />;
  }

  if (rows.length === 0) {
    return (
      <section className="space-y-4">
        <header className="space-y-2">
          <p className="text-sm text-muted-foreground">Interne Audit-Übersicht</p>
          <h1 className="text-2xl font-semibold tracking-normal">Audits</h1>
        </header>

        <article className="rounded-lg border p-4">
          <h2 className="text-sm font-medium">Noch keine Audits</h2>
          <p className="mt-1 text-sm text-muted-foreground">
            Sobald neue Audits oder laufende Audit-Generierungen angelegt
            wurden, erscheinen sie hier als kompakte Zeilen.
          </p>
        </article>
      </section>
    );
  }

  return (
    <section className="space-y-4">
      <header className="space-y-2">
        <p className="text-sm text-muted-foreground">Interne Audit-Übersicht</p>
        <h1 className="text-2xl font-semibold tracking-normal">Audits</h1>
      </header>

      <section className="space-y-2 overflow-x-auto">
        <div className="grid min-w-[840px] grid-cols-[minmax(0,1.2fr)_minmax(0,1fr)_170px_150px_auto] gap-2 rounded-md border bg-muted/40 px-3 py-2 text-xs font-medium text-muted-foreground">
          <span>Slug</span>
          <span>Domain</span>
          <span>Status</span>
          <span>Seiten/Phase</span>
          <span className="text-right">Aktion</span>
        </div>

        <div className="space-y-2">
          {rows.map((row: AuditDashboardRow) => (
            <article
              className="grid min-w-[840px] grid-cols-[minmax(0,1.2fr)_minmax(0,1fr)_170px_150px_auto] items-center gap-2 rounded-lg border px-3 py-2 text-sm"
              key={row.id}
            >
              <div className="min-w-0">
                <p className="truncate font-medium">{row.title}</p>
                {row.kind === "generation" ? (
                  <p className="truncate text-xs text-muted-foreground">
                    Run {row.runId}
                  </p>
                ) : null}
              </div>
              <p className="truncate text-muted-foreground">{row.checkedDomain}</p>
              <Badge
                className="h-auto min-h-6 justify-center whitespace-normal text-center"
                variant="secondary"
              >
                {row.kind === "audit"
                  ? getStatusLabel(row.status)
                  : getGenerationStatusLabel(row)}
              </Badge>
              <p className="text-muted-foreground">
                <span className="inline-flex items-center gap-1">
                  {row.kind === "audit" ? (
                    <>
                      <Files className="size-3.5" />
                      {formatPageCount(row.pageCount)}
                    </>
                  ) : (
                    <>
                      <Activity className="size-3.5" />
                      {getStageLabel(row.latestStage)}
                    </>
                  )}
                </span>
                {row.kind === "generation" && row.errorSummary ? (
                  <span className="mt-1 block truncate text-xs">
                    {row.errorSummary}
                  </span>
                ) : null}
              </p>
              <div className="flex justify-end">
                {row.kind === "audit" ? (
                  <Link
                    className="inline-flex min-h-8 items-center gap-1 text-sm text-primary"
                    href={row.detailHref}
                  >
                    <SquarePen className="size-4" />
                    Öffnen
                  </Link>
                ) : (
                  <span className="text-sm text-muted-foreground">Pipeline</span>
                )}
              </div>
            </article>
          ))}
        </div>
      </section>
    </section>
  );
}