import { useEffect, useRef, useState } from 'react';
import { Dialog, DialogContent, DialogHeader, DialogTitle, DialogDescription } from '@/components/ui/dialog';
import { Button } from '@/components/ui/button';
import { APP_VERSION, RELEASE_NOTES } from '@/lib/version';
import { Sparkles } from 'lucide-react';
import { useAuth } from '@/hooks/useAuth';
import { api } from '@/api';

// Written on close so the dialog doesn't flash during the brief window before
// /me resolves on repeat visits. The backend is authoritative; this is a cache.
const LS_KEY = `bt-release-seen-${APP_VERSION}`;

export function ReleaseNotesDialog() {
  const { hasNewVersion, setHasNewVersion } = useAuth();
  const [open, setOpen] = useState(false);
  const titleRef = useRef(null);

  useEffect(() => {
    if (hasNewVersion) setOpen(true);
  }, [hasNewVersion]);

  const handleClose = () => {
    localStorage.setItem(LS_KEY, '1');
    setOpen(false);
    setHasNewVersion(false);         // optimistic — don't wait for the server
    api.acknowledgeVersion().catch(() => {}); // fire-and-forget
    const prev = document.activeElement;
    if (prev?.focus) setTimeout(() => prev.focus(), 0);
  };

  return (
    <Dialog open={open} onOpenChange={v => { if (!v) handleClose(); }}>
      <DialogContent className="max-w-md">
        <DialogHeader>
          <div className="flex items-center gap-2 mb-1">
            <div className="flex h-8 w-8 items-center justify-center rounded-lg bg-primary/10">
              <Sparkles className="h-4 w-4 text-primary" />
            </div>
            <span className="text-xs font-medium text-muted-foreground uppercase tracking-wider">
              v{RELEASE_NOTES.version} · {RELEASE_NOTES.date}
            </span>
          </div>
          <DialogTitle ref={titleRef} className="text-xl">What's new</DialogTitle>
          <DialogDescription className="sr-only">
            Release highlights for BillTracker v{RELEASE_NOTES.version}
          </DialogDescription>
        </DialogHeader>

        <div className="mt-2 space-y-3" role="list" aria-label="Release highlights">
          {RELEASE_NOTES.highlights.map((item, i) => (
            <div key={i} className="flex gap-3 items-start" role="listitem">
              <span className="text-lg leading-none mt-0.5" aria-hidden="true">{item.icon}</span>
              <div>
                <p className="text-sm font-medium text-foreground">{item.title}</p>
                <p className="text-xs text-muted-foreground mt-0.5 leading-relaxed">{item.desc}</p>
              </div>
            </div>
          ))}
        </div>

        <div className="mt-4 pt-4 border-t border-border flex items-center justify-end">
          <Button size="sm" onClick={handleClose}>
            Got it
          </Button>
        </div>
      </DialogContent>
    </Dialog>
  );
}
