import { useCallback, useEffect, useState } from "react";
import { X } from "lucide-react";
import { Button } from "@/components/ui/button";
import { useNavigate } from "react-router-dom";
import { useClientNotifications } from "@/contexts/ClientNotificationContext";
import { resolveNotificationLink } from "@/components/generic/notificationDisplay";
import { getTierColor, getContrastText } from "@/utils/tierColors";
import AnnouncementCarouselDialog from "@/components/generic/AnnouncementCarouselDialog";

const ROTATE_INTERVAL_MS = 6000;

// resolveNotificationLink already gives explicit link_url (the admin "On
// Open" section) precedence over the type-based fallbacks, for broadcasts
// sent before that field existed.
function resolveClickAction(stickyAnnouncement) {
  return resolveNotificationLink(stickyAnnouncement.type, stickyAnnouncement.data);
}

export default function StickyAnnouncementBar() {
  const navigate = useNavigate();
  const { stickyAnnouncements, bannerImage, markSeen } = useClientNotifications();
  const [activeIndex, setActiveIndex] = useState(0);
  const [detailsOpen, setDetailsOpen] = useState(false);

  const count = stickyAnnouncements.length;
  // Derived rather than clamped via effect — safe the instant the array
  // shrinks (e.g. after a dismiss), no render with a stale out-of-range index.
  const safeIndex = count ? Math.min(activeIndex, count - 1) : 0;

  // Auto-rotate through active announcements while more than one is live.
  useEffect(() => {
    if (count <= 1) return;
    const id = setInterval(() => {
      setActiveIndex((i) => (i + 1) % count);
    }, ROTATE_INTERVAL_MS);
    return () => clearInterval(id);
  }, [count]);

  const current = stickyAnnouncements[safeIndex];

  const onDismiss = useCallback(async () => {
    if (!current) return;
    await markSeen(current.notification_id);
  }, [current, markSeen]);

  // Opening the dialog must NOT mark it seen — markSeen removes the row from
  // stickyAnnouncements, which would unmount this component (dialog included)
  // before it ever shows.
  const onClickBanner = useCallback(() => {
    if (!current) return;
    setDetailsOpen(true);
  }, [current]);

  // Closing the details dialog (X, Escape, overlay click — any reason)
  // dismisses whichever announcement was being viewed at the time. This is
  // the only dismiss path when multiple are active (no per-item X on the bar
  // itself — see the count > 1 branch below).
  const onDialogOpenChange = useCallback((open) => {
    setDetailsOpen(open);
    if (!open) void onDismiss();
  }, [onDismiss]);

  if (!current) return null;

  const swatch      = getTierColor(current.color || "indigo").swatch;
  const textColor   = getContrastText(swatch, current.color || "indigo");
  const clickAction = resolveClickAction(current);

  return (
    <>
      <div role="status" className="w-full shadow-sm px-4 md:px-6" style={{ backgroundColor: swatch }}>
        <div
          onClick={onClickBanner}
          className="relative w-full cursor-pointer rounded-none py-3 flex items-center justify-center gap-4 px-10"
        >
          <div className="flex items-center gap-3 min-w-0">
            <p className="text-sm font-semibold leading-snug truncate" style={{ color: textColor }}>
              {current.title || "Announcement"}
            </p>

            {clickAction && (
              <Button
                variant="outline"
                size="sm"
                className="shrink-0 text-foreground"
                onClick={(e) => {
                  e.preventDefault();
                  e.stopPropagation();
                  clickAction.go(navigate);
                }}
              >
                {clickAction.label}
              </Button>
            )}
          </div>

          {count > 1 && (
            <div className="absolute right-2 flex items-center gap-1.5">
              {stickyAnnouncements.map((a, i) => (
                <button
                  key={a.notification_id}
                  type="button"
                  aria-label={`Show announcement ${i + 1}`}
                  onClick={(e) => {
                    e.preventDefault();
                    e.stopPropagation();
                    setActiveIndex(i);
                  }}
                  className="size-1.5 rounded-full transition-opacity"
                  style={{ backgroundColor: textColor, opacity: i === safeIndex ? 1 : 0.35 }}
                />
              ))}
            </div>
          )}

          {/* Dismiss-X only makes sense for a single active announcement —
              with multiple, the dialog's own close button (shadcn Dialog)
              is the way to close/step away, no per-item dismiss from the bar. */}
          {count <= 1 && (
            <div
              role="button"
              tabIndex={0}
              onClick={(e) => {
                e.preventDefault();
                e.stopPropagation();
                void onDismiss();
              }}
              onKeyDown={(e) => {
                if (e.key !== "Enter" && e.key !== " ") return;
                e.preventDefault();
                e.stopPropagation();
                void onDismiss();
              }}
              aria-label="Dismiss sticky announcement"
              title="Dismiss"
              className="absolute right-2 inline-flex items-center justify-center size-8 rounded-lg cursor-pointer hover:opacity-70 transition-opacity"
              style={{ color: textColor }}
            >
              <X className="size-4" />
            </div>
          )}
        </div>
      </div>

      <AnnouncementCarouselDialog
        open={detailsOpen}
        onOpenChange={onDialogOpenChange}
        announcements={stickyAnnouncements}
        activeIndex={safeIndex}
        onIndexChange={setActiveIndex}
        resolveClickAction={resolveClickAction}
        navigate={navigate}
        bannerImage={bannerImage}
      />
    </>
  );
}