"use client";

import { MessageSquare, Trash2 } from "lucide-react";
import { useEffect, useState, useTransition } from "react";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { addComment, deleteComment, listComments, type CommentDto } from "@/modules/_core/comments";

type Props = {
  entityType: string;
  entityId: string;
  currentUserId: string;
  compact?: boolean;
};

export function EntityComments({ entityType, entityId, currentUserId, compact = false }: Props) {
  const [open, setOpen] = useState(!compact);
  const [comments, setComments] = useState<CommentDto[]>([]);
  const [draft, setDraft] = useState("");
  const [isPending, startTransition] = useTransition();

  useEffect(() => {
    if (!open) return;
    listComments(entityType, entityId)
      .then(setComments)
      .catch(() => setComments([]));
  }, [entityType, entityId, open]);

  function submitComment() {
    const body = draft.trim();
    if (!body) return;
    startTransition(async () => {
      const created = await addComment({ entityType, entityId, body });
      setComments((current) => [...current, created]);
      setDraft("");
    });
  }

  function removeComment(id: string) {
    startTransition(async () => {
      await deleteComment({ id });
      setComments((current) => current.filter((comment) => comment.id !== id));
    });
  }

  return (
    <div className={compact ? "mt-1" : "mt-3 border-t border-[var(--hair)] pt-3"}>
      {compact ? (
        <button
          type="button"
          className="inline-flex items-center gap-1 text-[12px] text-[var(--ink-mute)] hover:text-[var(--ink)]"
          onClick={() => setOpen((value) => !value)}
        >
          <MessageSquare className="size-3.5" />
          {open ? "Hide comments" : "Comments"}
          {comments.length > 0 ? ` (${comments.length})` : ""}
        </button>
      ) : (
        <div className="eyebrow mb-2">Comments</div>
      )}

      {open && (
        <div className="mt-2 space-y-2">
          {comments.length === 0 ? (
            <p className="text-[12px] text-[var(--ink-mute)]">No comments yet.</p>
          ) : (
            <ul className="space-y-2">
              {comments.map((comment) => (
                <li
                  key={comment.id}
                  className="rounded-md border border-[var(--hair)] px-2.5 py-2 text-[13px]"
                >
                  <div className="flex items-start justify-between gap-2">
                    <div className="min-w-0">
                      <div className="text-[11px] text-[var(--ink-mute)]">
                        {comment.authorName ?? "Someone"} · {formatCommentTime(comment.createdAt)}
                      </div>
                      <p className="mt-0.5 whitespace-pre-wrap break-words">{comment.body}</p>
                    </div>
                    {comment.authorId === currentUserId ? (
                      <Button
                        type="button"
                        size="icon-sm"
                        variant="ghost"
                        aria-label="Delete comment"
                        disabled={isPending}
                        onClick={() => removeComment(comment.id)}
                      >
                        <Trash2 className="size-3.5" />
                      </Button>
                    ) : null}
                  </div>
                </li>
              ))}
            </ul>
          )}

          <div className="flex gap-2">
            <Input
              value={draft}
              onChange={(e) => setDraft(e.target.value)}
              placeholder="Add a comment…"
              disabled={isPending}
              onKeyDown={(e) => {
                if (e.key === "Enter") {
                  e.preventDefault();
                  submitComment();
                }
              }}
            />
            <Button
              type="button"
              size="sm"
              disabled={!draft.trim() || isPending}
              onClick={submitComment}
            >
              Post
            </Button>
          </div>
        </div>
      )}
    </div>
  );
}

function formatCommentTime(iso: string): string {
  return new Date(iso).toLocaleString(undefined, {
    month: "short",
    day: "numeric",
    hour: "numeric",
    minute: "2-digit",
  });
}