import Link from "next/link";
import { getTranslations } from "next-intl/server";
import { Info, Lightbulb, MapPin } from "lucide-react";
import { formatDistance } from "@/lib/geo/distance";
import { wallClock } from "@/lib/planning/days";
import { formatDayShort, formatMinutes } from "@/lib/planning/text";
import { buttonCls } from "@/components/work-orders/button-cls";
import { Section } from "@/components/work-orders/ui";
import type { ServiceCtx } from "@/server/services/context";
import { findNearbyUnplanned, recommendAssignments } from "@/server/services/planning/recommend";

/**
 * "Einsatz-Vorschläge" in the backoffice work order detail (L13, additive). Never breaks the page:
 * any error hides the section. "Übernehmen" opens the planning board with a prefilled popover.
 */
export async function PlanningSuggestions({ ctx, workOrderId, locale, tz }: { ctx: ServiceCtx; workOrderId: string; locale: string; tz: string }) {
  let rec: Awaited<ReturnType<typeof recommendAssignments>>;
  let nearby: Awaited<ReturnType<typeof findNearbyUnplanned>>;
  try {
    [rec, nearby] = await Promise.all([recommendAssignments(ctx, { workOrderId, locale: locale === "en" ? "en" : "de" }), findNearbyUnplanned(ctx, { workOrderId })]);
  } catch {
    return null;
  }
  if (rec.status === "not_schedulable") return null;
  const t = await getTranslations("planning");
  const boardLink = (day: string | null, teamId: string | null, time: string | null, id = workOrderId) => {
    const qs = new URLSearchParams({ schedule: id });
    if (day) {
      qs.set("date", day);
      qs.set("day", day);
    }
    if (teamId) qs.set("scheduleTeam", teamId);
    if (time) qs.set("time", time);
    return `/planning?${qs}`;
  };

  return (
    <Section
      title={t("recommend.sectionTitle")}
      className="mt-4"
      actions={
        <Link href="/planning" className={buttonCls("ghost")}>
          {t("recommend.openBoard")}
        </Link>
      }
    >
      <p className="mb-2 flex items-center gap-1.5 text-xs text-muted-foreground">
        <Lightbulb className="size-3.5 text-[var(--info)]" aria-hidden />
        {t("recommend.sub")}
      </p>
      {rec.hint && (
        <p className="mb-2 flex items-start gap-1.5 text-sm">
          <Info className="mt-0.5 size-4 shrink-0 text-[var(--info)]" aria-hidden />
          {rec.hint}
        </p>
      )}
      {rec.recommendations.length > 0 && (
        <ul className="grid gap-2 md:grid-cols-2 xl:grid-cols-3">
          {rec.recommendations.map((r) => (
            <li key={`${r.teamId}-${r.day}`} className="rounded-lg border p-3 text-sm" title={r.text}>
              <p className="font-semibold">
                {t("recommend.card", { day: formatDayShort(r.day, locale), team: r.teamName, distance: formatDistance(r.distanceKm, locale), number: r.nearOrder.number, free: formatMinutes(r.freeMinutes, locale) })}
              </p>
              {r.tight && <p className="text-xs font-semibold text-[var(--warn)]">{t("recommend.tight")}</p>}
              <Link href={boardLink(r.day, r.teamId, wallClock(new Date(r.suggestedStart), tz))} className={`${buttonCls("outline")} mt-2 w-full`}>
                {t("recommend.take")}
              </Link>
            </li>
          ))}
        </ul>
      )}
      {nearby.status === "ok" && nearby.items.length > 0 && (
        <div className="mt-3 border-t pt-3">
          <h3 className="text-sm font-semibold">{t("recommend.nearbyTitle")}</h3>
          <p className="text-xs text-muted-foreground">{t("recommend.nearbyQuestion", { radius: nearby.radiusKm })}</p>
          <ul className="mt-1.5 space-y-1">
            {nearby.items.map((o) => {
              const first = rec.recommendations[0];
              return (
                <li key={o.id} className="flex flex-wrap items-center gap-2 text-sm">
                  <MapPin className="size-3.5" aria-hidden />
                  <Link href={`/work-orders/${o.id}`} className="font-mono font-semibold underline-offset-2 hover:underline">
                    {o.number}
                  </Link>
                  <span>{o.customerName}</span>
                  <span className="text-muted-foreground">· {formatDistance(o.distanceKm, locale)}</span>
                  <Link href={boardLink(first?.day ?? null, first?.teamId ?? null, null, o.id)} className="ml-auto inline-flex min-h-11 items-center text-xs font-semibold underline-offset-2 hover:underline">
                    {t("recommend.planTogether")}
                  </Link>
                </li>
              );
            })}
          </ul>
        </div>
      )}
    </Section>
  );
}