import { useState } from "react";
import { TIMEZONE_OPTIONS } from "~/components/league/TimezoneSelect";

const VALID_TIMEZONES = new Set(
  TIMEZONE_OPTIONS.flatMap((g) => g.zones.map((z) => z.value))
);

interface TimezonePromptBannerProps {
  /** Called with the saved timezone value after a successful POST. */
  onSaved?: (timezone: string) => void;
}

export function TimezonePromptBanner({ onSaved }: TimezonePromptBannerProps) {
  const [dismissed, setDismissed] = useState(false);
  const [saving, setSaving] = useState(false);
  const [saved, setSaved] = useState(false);

  if (dismissed || saved) return null;

  const detectedTz =
    typeof window !== "undefined"
      ? (() => {
          try {
            const tz = Intl.DateTimeFormat().resolvedOptions().timeZone;
            return VALID_TIMEZONES.has(tz) ? tz : null;
          } catch {
            return null;
          }
        })()
      : null;

  if (!detectedTz) return null;

  const handleSave = async () => {
    setSaving(true);
    try {
      const body = new FormData();
      body.set("timezone", detectedTz);
      const res = await fetch("/api/user/timezone", { method: "POST", body });
      if (res.ok) {
        setSaved(true);
        onSaved?.(detectedTz);
      }
    } finally {
      setSaving(false);
    }
  };

  return (
    <div className="flex items-center justify-between gap-3 px-4 py-2 bg-blue-950/40 border-b border-blue-800/40 text-sm text-blue-200">
      <span>
        Set your timezone to <strong>{detectedTz}</strong> for overnight pick
        protection?
      </span>
      <div className="flex items-center gap-2 shrink-0">
        <button
          onClick={handleSave}
          disabled={saving}
          className="px-3 py-1 rounded bg-blue-700 hover:bg-blue-600 text-white text-xs font-medium disabled:opacity-50"
        >
          {saving ? "Saving…" : "Save"}
        </button>
        <button
          onClick={() => setDismissed(true)}
          className="text-blue-400 hover:text-blue-200 text-xs"
        >
          Dismiss
        </button>
      </div>
    </div>
  );
}