"use client";

import { useRouter } from "next/navigation";
import { useActionState, useEffect } from "react";
import { useTranslations } from "next-intl";
import { CheckCircle2, Clock, Info, Mail, XCircle } from "lucide-react";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Label } from "@/components/ui/label";
import { Textarea } from "@/components/ui/textarea";
import { sendReportToCustomerAction } from "@/server/actions/reports/send-to-customer";
import { SEND_TO_CUSTOMER_IDLE } from "./send-to-customer-state";

export type CustomerMailingRow = { id: string; to: string; status: string; version: number | null; when: string };

const KNOWN_REASONS = new Set(["recipient_missing", "report_not_approved", "pdf_missing"]);

/** /reports/[id] section „An Kunden senden" (approved + report:approve). The service enforces rights and status. */
export function SendToCustomer({ reportId, defaultTo, mailings }: { reportId: string; defaultTo: string | null; mailings: CustomerMailingRow[] }) {
  const t = useTranslations("reports.customerMail");
  const tr = useTranslations("reports");
  const router = useRouter();
  const [state, action, pending] = useActionState(sendReportToCustomerAction, SEND_TO_CUSTOMER_IDLE);

  useEffect(() => {
    if (state.status === "ok") router.refresh();
  }, [state, router]);

  let feedback: React.ReactNode = null;
  if (state.status === "ok") {
    const bad = state.result === "failed";
    const hint = state.result === "duplicate";
    feedback = (
      <p role={bad ? "alert" : "status"} className={`flex items-center gap-2 text-[13px] font-semibold ${bad ? "text-[var(--risk)]" : hint ? "text-muted-foreground" : "text-[var(--ok)]"}`}>
        {bad ? <XCircle className="size-4 shrink-0" aria-hidden /> : hint ? <Info className="size-4 shrink-0" aria-hidden /> : <CheckCircle2 className="size-4 shrink-0" aria-hidden />}
        {t(`result.${state.result}`, { to: state.to })}
      </p>
    );
  } else if (state.status === "error") {
    const key =
      state.reason && KNOWN_REASONS.has(state.reason)
        ? `errors.${state.reason}`
        : state.field === "to"
          ? "errors.invalid_to"
          : null;
    feedback = (
      <p role="alert" className="flex items-center gap-2 rounded-lg border border-[var(--risk)] px-3 py-2 text-[13px] font-semibold text-[var(--risk)]">
        <XCircle className="size-4 shrink-0" aria-hidden />
        {key ? t(key) : tr(`errors.${state.code}`)}
      </p>
    );
  }

  return (
    <section className="shadow-card rounded-xl border bg-card p-4" aria-labelledby="customer-mail-title">
      <h2 id="customer-mail-title" className="font-heading text-[15px] font-semibold">
        {t("title")}
      </h2>
      <p className="mt-1 text-[12.5px] text-muted-foreground">{t("sub")}</p>

      <form action={action} className="mt-3 space-y-3">
        <input type="hidden" name="reportId" value={reportId} />
        <div>
          <Label htmlFor="customer-mail-to">{t("to")} *</Label>
          <Input
            id="customer-mail-to"
            name="to"
            type="email"
            required
            maxLength={254}
            autoComplete="email"
            defaultValue={defaultTo ?? ""}
            className="mt-1 h-11"
            aria-invalid={state.status === "error" && state.field === "to"}
            aria-describedby="customer-mail-to-hint"
          />
          <p id="customer-mail-to-hint" className="mt-1 text-[12px] text-muted-foreground">
            {defaultTo ? t("toHint") : t("noDefault")}
          </p>
        </div>
        <div>
          <Label htmlFor="customer-mail-message">{t("message")}</Label>
          <Textarea id="customer-mail-message" name="message" maxLength={2000} rows={3} className="mt-1 min-h-20" placeholder={t("messagePlaceholder")} />
        </div>
        {feedback}
        <Button type="submit" disabled={pending} className="h-11 px-4">
          <Mail aria-hidden />
          {pending ? t("sending") : t("submit")}
        </Button>
      </form>

      <h3 className="mt-4 text-[13px] font-semibold">{t("history")}</h3>
      {mailings.length === 0 ? (
        <p className="mt-1 text-[12.5px] text-muted-foreground">{t("historyEmpty")}</p>
      ) : (
        <ul className="mt-2 space-y-1.5">
          {mailings.map((m) => (
            <li key={m.id} className="flex flex-wrap items-center justify-between gap-2 text-[13px]">
              <span className="min-w-0 break-all">
                {m.to}
                <span className="text-muted-foreground">
                  {" · "}
                  {m.when}
                  {m.version ? ` · v${m.version}` : ""}
                </span>
              </span>
              <DeliveryStatus status={m.status} label={t(`delivery.${m.status === "sent" || m.status === "pending" || m.status === "failed" ? m.status : "other"}`)} />
            </li>
          ))}
        </ul>
      )}
    </section>
  );
}

function DeliveryStatus({ status, label }: { status: string; label: string }) {
  const Icon = status === "sent" ? CheckCircle2 : status === "pending" ? Clock : XCircle;
  const tone = status === "sent" ? "text-[var(--ok)]" : status === "pending" ? "text-muted-foreground" : "text-[var(--risk)]";
  return (
    <span className={`inline-flex items-center gap-1 text-[12.5px] font-semibold ${tone}`}>
      <Icon className="size-3.5" aria-hidden />
      {label}
    </span>
  );
}