"use client";

import Link from "next/link";
import { useDraggable } from "@dnd-kit/core";
import { CSS } from "@dnd-kit/utilities";
import { Badge } from "@/components/ui/badge";
import { Avatar, AvatarFallback } from "@/components/ui/avatar";
import {
  Item,
  ItemContent,
  ItemFooter,
  ItemHeader,
  ItemTitle,
} from "@/components/ui/item";
import {
  PRIORITY_LABEL,
  PRIORITY_STYLES,
  STATUS_LABEL,
  STATUS_STYLES,
  type TicketPriority,
  type TicketStatus,
} from "@/lib/tickets/ticketMeta";
import { TYPE_LABEL, TYPE_STYLES } from "@/lib/projects/projectMeta";
import { cn } from "@/lib/utils";
import type { KanbanTicket } from "./KanbanBoard";

interface KanbanTicketCardProps {
  readonly ticket: KanbanTicket;
  readonly overlay?: boolean;
}

function isTicketStatus(value: string): value is TicketStatus {
  return value in STATUS_STYLES;
}

function isTicketPriority(value: string): value is TicketPriority {
  return value in PRIORITY_STYLES;
}

function initials(displayName: string): string {
  const parts = displayName.trim().split(/\s+/).filter(Boolean);
  const first = parts[0]?.[0] ?? "?";
  const last = parts.length > 1 ? (parts.at(-1)?.[0] ?? "") : "";
  return `${first}${last}`.toUpperCase();
}

function badgeStyle(value: string, styles: Readonly<Record<string, string>>): string {
  return styles[value] ?? "bg-muted/50 text-muted-foreground border-border";
}

function ticketTypeLabel(type: string): string {
  return TYPE_LABEL[type] ?? type.replaceAll("_", " ");
}

function KanbanTicketCardBody({ ticket, overlay }: KanbanTicketCardProps) {
  const priorityLabel = isTicketPriority(ticket.priority)
    ? PRIORITY_LABEL[ticket.priority]
    : ticket.priority;
  const statusStyle = isTicketStatus(ticket.status) ? STATUS_STYLES[ticket.status] : "";
  const statusLabel = isTicketStatus(ticket.status)
    ? STATUS_LABEL[ticket.status]
    : ticket.status.replaceAll("_", " ");

  return (
    <Item
      variant="outline"
      size="sm"
      className={cn(
        "items-start gap-3 bg-background/50 transition-colors hover:bg-accent/50",
        overlay && "opacity-90 shadow-lg",
      )}
    >
        <ItemHeader className="items-center">
          <Badge
            variant="outline"
            className={cn(
              "text-[10px] uppercase tracking-wide",
              TYPE_STYLES[ticket.type] ?? "bg-muted/50 text-muted-foreground border-border",
            )}
          >
            {ticketTypeLabel(ticket.type)}
          </Badge>
          <span className="font-mono text-[10px] text-muted-foreground">#{ticket.id}</span>
        </ItemHeader>

        <ItemContent className="w-full min-w-0 gap-2">
          <ItemTitle className="w-full min-w-0 text-sm font-semibold">
            <Link href={`/helpdesk/${ticket.id}`} className="line-clamp-2 hover:underline">
              {ticket.title}
            </Link>
          </ItemTitle>
          <div className="flex flex-wrap items-center gap-1.5">
            <Badge variant="outline" className={cn("text-[10px] uppercase tracking-wide", statusStyle)}>
              {statusLabel}
            </Badge>
            <Badge
              variant="outline"
              className={cn("text-[10px] uppercase tracking-wide", badgeStyle(ticket.priority, PRIORITY_STYLES))}
            >
              {priorityLabel}
            </Badge>
            {ticket.storyPoints != null && (
              <Badge variant="secondary" className="font-mono text-[10px]">
                {ticket.storyPoints} pts
              </Badge>
            )}
          </div>
        </ItemContent>

        <ItemFooter className="w-full min-w-0 flex-wrap items-center gap-2 text-xs text-muted-foreground">
          <div className="flex min-w-0 flex-1 items-center gap-2">
            {ticket.assignee ? (
              <>
                <Avatar className="size-5">
                  <AvatarFallback className="text-[9px]">{initials(ticket.assignee.displayName)}</AvatarFallback>
                </Avatar>
                <span className="truncate">{ticket.assignee.displayName}</span>
              </>
            ) : (
              <span>Unassigned</span>
            )}
          </div>
          <div className="flex shrink-0 items-center gap-1" aria-label="Ticket labels">
            {ticket.labels.map((label) => (
              <span
                key={label.id}
                title={label.name}
                aria-label={label.name}
                className="size-2 rounded-full border border-border"
                style={{ backgroundColor: label.color }}
              />
            ))}
          </div>
          {ticket.reporter && <span className="max-w-full truncate">reported by {ticket.reporter.displayName}</span>}
        </ItemFooter>
    </Item>
  );
}

export function KanbanTicketCard({ ticket, overlay = false }: KanbanTicketCardProps) {
  const { attributes, listeners, setNodeRef, transform, isDragging } = useDraggable({ id: ticket.id });
  const style = transform ? { transform: CSS.Translate.toString(transform) } : undefined;

  return (
    <div
      ref={setNodeRef}
      style={style}
      {...listeners}
      {...attributes}
      className={cn("touch-none outline-none", isDragging && "opacity-40")}
    >
      <KanbanTicketCardBody ticket={ticket} overlay={overlay} />
    </div>
  );
}

export function KanbanTicketOverlay({ ticket }: { readonly ticket: KanbanTicket }) {
  return (
    <div className="touch-none">
      <KanbanTicketCardBody ticket={ticket} overlay />
    </div>
  );
}