"use client";

import { useMemo } from "react";
import Link from "next/link";
import { trpc } from "~/lib/trpc/client.js";
import type { WidgetProps } from "../widget-registry.js";
import { InfoTooltip } from "~/components/ui/InfoTooltip.js";
import { FadeIn } from "~/components/ui/FadeIn.js";

const STATUS_DOT: Record<string, string> = {
  ACTIVE: "bg-green-500",
  DRAFT: "bg-gray-400",
  ON_HOLD: "bg-yellow-500",
  COMPLETED: "bg-blue-500",
  CANCELLED: "bg-red-400",
};

export function MyProjectsWidget({ config }: WidgetProps) {
  const showFavorites = (config as { showFavorites?: boolean }).showFavorites !== false;
  const showResponsible = (config as { showResponsible?: boolean }).showResponsible !== false;

  const { data: favoriteIds } = trpc.user.getFavoriteProjectIds.useQuery(undefined, {
    staleTime: 30_000,
    enabled: showFavorites,
  });

  const { data: projectsData } = trpc.project.listWithCosts.useQuery(
    { limit: 200 },
    { staleTime: 30_000 },
  );

  const { data: session } = trpc.user.me.useQuery(undefined, { staleTime: 60_000 });

  const favorites = favoriteIds ?? [];
  const allProjects = (projectsData?.projects ?? []) as Array<{
    id: string;
    shortCode: string;
    name: string;
    status: string;
    responsiblePerson?: string | null;
    budgetCents?: number;
    startDate?: Date | string;
    endDate?: Date | string;
  }>;

  const userName = session?.name ?? "";

  const { favoriteProjects, responsibleProjects } = useMemo(() => {
    const favSet = new Set(favorites);
    const favProjects = showFavorites
      ? allProjects.filter((p) => favSet.has(p.id))
      : [];
    const respProjects = showResponsible && userName
      ? allProjects.filter((p) => p.responsiblePerson?.toLowerCase().includes(userName.toLowerCase()) && !favSet.has(p.id))
      : [];
    return { favoriteProjects: favProjects, responsibleProjects: respProjects };
  }, [allProjects, favorites, showFavorites, showResponsible, userName]);

  const toggleMutation = trpc.user.toggleFavoriteProject.useMutation({
    onSuccess: () => {
      void trpc.useUtils().user.getFavoriteProjectIds.invalidate();
    },
  });

  const isEmpty = favoriteProjects.length === 0 && responsibleProjects.length === 0;

  return (
    <div className="h-full flex flex-col">
      {isEmpty && (
        <div className="flex-1 flex items-center justify-center text-sm text-gray-400 dark:text-gray-500">
          <div className="text-center">
            <div className="text-2xl mb-1">⭐</div>
            <p>No favorite projects yet.</p>
            <p className="text-xs mt-1">Star projects from the project list to see them here.</p>
          </div>
        </div>
      )}

      {!isEmpty && (
        <div className="flex-1 overflow-y-auto divide-y divide-gray-100 dark:divide-gray-800">
          {favoriteProjects.length > 0 && (
            <div>
              <div className="px-3 py-1.5 text-[10px] font-semibold uppercase tracking-wider text-amber-600 dark:text-amber-400 bg-amber-50/50 dark:bg-amber-900/10 flex items-center">
                Favorites
                <InfoTooltip content="Projects you have starred. Click the star icon on any project to add or remove it from your favorites." />
              </div>
              {favoriteProjects.map((p, i) => (
                <FadeIn key={p.id} delay={i * 0.03} direction="up">
                  <ProjectRow project={p} isFavorite onToggleFavorite={() => toggleMutation.mutate({ projectId: p.id })} />
                </FadeIn>
              ))}
            </div>
          )}

          {responsibleProjects.length > 0 && (
            <div>
              <div className="px-3 py-1.5 text-[10px] font-semibold uppercase tracking-wider text-brand-600 dark:text-brand-400 bg-brand-50/50 dark:bg-brand-900/10 flex items-center">
                Responsible
                <InfoTooltip content="Projects where you are listed as the responsible person. These are automatically shown based on your user name." />
              </div>
              {responsibleProjects.map((p, i) => (
                <FadeIn key={p.id} delay={i * 0.03} direction="up">
                  <ProjectRow project={p} isFavorite={false} onToggleFavorite={() => toggleMutation.mutate({ projectId: p.id })} />
                </FadeIn>
              ))}
            </div>
          )}
        </div>
      )}
    </div>
  );
}

function ProjectRow({
  project,
  isFavorite,
  onToggleFavorite,
}: {
  project: { id: string; shortCode: string; name: string; status: string };
  isFavorite: boolean;
  onToggleFavorite: () => void;
}) {
  return (
    <div className="flex items-center gap-2 px-3 py-2 hover:bg-gray-50 dark:hover:bg-gray-800/30 transition-colors group">
      <button
        type="button"
        onClick={(e) => { e.preventDefault(); onToggleFavorite(); }}
        className={`flex-shrink-0 text-sm transition-colors ${isFavorite ? "text-amber-500" : "text-gray-300 dark:text-gray-600 opacity-0 group-hover:opacity-100"}`}
        title={isFavorite ? "Remove from favorites" : "Add to favorites"}
      >
        {isFavorite ? "★" : "☆"}
      </button>
      <div className={`w-2 h-2 rounded-full flex-shrink-0 ${STATUS_DOT[project.status] ?? "bg-gray-400"}`} />
      <Link
        href={`/projects/${project.id}`}
        className="min-w-0 flex-1 truncate text-sm text-gray-900 dark:text-gray-100 hover:text-brand-600 dark:hover:text-brand-400"
      >
        <span className="font-mono text-xs text-gray-400 dark:text-gray-500 mr-1.5">{project.shortCode}</span>
        {project.name}
      </Link>
      <span className="flex-shrink-0 text-[10px] text-gray-400 dark:text-gray-500 uppercase" title={`Project status: ${project.status}`}>{project.status}</span>
    </div>
  );
}