"use client";

import { useState } from "react";
import { trpc } from "~/lib/trpc/client.js";
import type { WidgetProps } from "~/components/dashboard/widget-registry.js";
import { InfoTooltip } from "~/components/ui/InfoTooltip.js";

type SortKey = "eid" | "name" | "chapter" | "score" | "lcr";

export function TopValueWidget({ config }: WidgetProps) {
  const limit = (config.limit as number) || 10;

  const [sortKey, setSortKey] = useState<SortKey>("score");
  const [sortDir, setSortDir] = useState<"asc" | "desc">("desc");

  function toggleSort(key: SortKey) {
    if (sortKey === key) setSortDir((d) => (d === "asc" ? "desc" : "asc"));
    else { setSortKey(key); setSortDir(key === "score" ? "desc" : "asc"); }
  }

  const { data, isLoading } = trpc.dashboard.getTopValueResources.useQuery(
    { limit },
    { staleTime: 60_000, placeholderData: (prev) => prev },
  );

  if (isLoading) {
    return (
      <div className="flex flex-col gap-1 pt-1">
        {[...Array(8)].map((_, i) => (
          <div key={i} className="flex items-center gap-3 px-3 py-2">
            <div className="h-3 w-4 shimmer-skeleton rounded" />
            <div className="h-3 w-10 shimmer-skeleton rounded font-mono" />
            <div className="h-3 flex-1 shimmer-skeleton rounded" />
            <div className="h-3 w-16 shimmer-skeleton rounded" />
            <div className="h-5 w-10 shimmer-skeleton rounded-full" />
            <div className="h-3 w-12 shimmer-skeleton rounded" />
          </div>
        ))}
      </div>
    );
  }

  const list = data ?? [];

  if (list.length === 0) {
    return (
      <div className="flex flex-col items-center justify-center h-full text-center py-8 text-gray-400 text-sm">
        <p>No scores computed yet or you lack access.</p>
        <p className="text-xs mt-1">Admins can recompute scores in Settings.</p>
      </div>
    );
  }

  const sorted = [...list].sort((a, b) => {
    const mult = sortDir === "asc" ? 1 : -1;
    switch (sortKey) {
      case "eid": return mult * a.eid.localeCompare(b.eid);
      case "name": return mult * a.displayName.localeCompare(b.displayName);
      case "chapter": return mult * (a.chapter ?? "").localeCompare(b.chapter ?? "");
      case "score": return mult * ((a.valueScore ?? 0) - (b.valueScore ?? 0));
      case "lcr": return mult * (a.lcrCents - b.lcrCents);
      default: return 0;
    }
  });

  function Ind({ k }: { k: SortKey }) {
    return sortKey === k
      ? <span className="text-[10px] ml-0.5">{sortDir === "asc" ? "▲" : "▼"}</span>
      : <span className="text-[10px] ml-0.5 text-gray-300">⇅</span>;
  }

  return (
    <div className="overflow-auto h-full">
      <table className="w-full text-xs">
        <thead className="bg-gray-50 sticky top-0">
          <tr>
            <th className="px-3 py-2 text-left font-medium text-gray-500 w-8">
              <span className="inline-flex items-center">
                #
                <InfoTooltip content="Rank position based on the current sort order." />
              </span>
            </th>
            <th className="px-3 py-2 text-left font-medium text-gray-500">
              <span className="inline-flex items-center">
                <button type="button" onClick={() => toggleSort("eid")} className="inline-flex items-center hover:text-gray-700 cursor-pointer">
                  EID<Ind k="eid" />
                </button>
                <InfoTooltip content="Employee ID — unique identifier for each resource." />
              </span>
            </th>
            <th className="px-3 py-2 text-left font-medium text-gray-500">
              <span className="inline-flex items-center">
                <button type="button" onClick={() => toggleSort("name")} className="inline-flex items-center hover:text-gray-700 cursor-pointer">
                  Name<Ind k="name" />
                </button>
                <InfoTooltip content="Display name of the resource." />
              </span>
            </th>
            <th className="px-3 py-2 text-left font-medium text-gray-500">
              <span className="inline-flex items-center">
                <button type="button" onClick={() => toggleSort("chapter")} className="inline-flex items-center hover:text-gray-700 cursor-pointer">
                  Chapter<Ind k="chapter" />
                </button>
                <InfoTooltip content="Organizational chapter (team/department) the resource belongs to." />
              </span>
            </th>
            <th className="px-3 py-2 text-right font-medium text-gray-500">
              <span className="inline-flex items-center justify-end">
                <button type="button" onClick={() => toggleSort("score")} className="inline-flex items-center hover:text-gray-700 cursor-pointer">
                  Score<Ind k="score" />
                </button>
                <InfoTooltip
                  content={
                    <span>
                      Composite price/quality score 0–100.<br />
                      Weights: Skill Depth 30% · Cost Efficiency 25% · Skill Breadth 15% · Chargeability 15% · Experience 15%.<br />
                      Recompute in Admin → Settings.
                    </span>
                  }
                  width="w-72"
                />
              </span>
            </th>
            <th className="px-3 py-2 text-right font-medium text-gray-500">
              <span className="inline-flex items-center justify-end">
                <button type="button" onClick={() => toggleSort("lcr")} className="inline-flex items-center hover:text-gray-700 cursor-pointer">
                  LCR (€)<Ind k="lcr" />
                </button>
                <InfoTooltip content="Labour Cost Rate — hourly cost in EUR. Lower LCR = better cost efficiency score." />
              </span>
            </th>
          </tr>
        </thead>
        <tbody className="divide-y divide-gray-100">
          {sorted.map((r, i) => (
            <tr key={r.id} className="hover:bg-gray-50">
              <td className="px-3 py-2 text-gray-400 font-medium">{i + 1}</td>
              <td className="px-3 py-2 font-mono text-gray-600">{r.eid}</td>
              <td className="px-3 py-2 font-medium text-gray-900">{r.displayName}</td>
              <td className="px-3 py-2 text-gray-500">{r.chapter ?? "—"}</td>
              <td className="px-3 py-2 text-right">
                <span
                  className={`inline-block px-2 py-0.5 rounded-full font-semibold ${
                    (r.valueScore ?? 0) >= 70
                      ? "bg-green-100 text-green-700"
                      : (r.valueScore ?? 0) >= 40
                      ? "bg-amber-100 text-amber-700"
                      : "bg-red-100 text-red-700"
                  }`}
                >
                  {r.valueScore ?? "—"}
                </span>
              </td>
              <td className="px-3 py-2 text-right text-gray-700">{(r.lcrCents / 100).toFixed(0)}</td>
            </tr>
          ))}
        </tbody>
      </table>
    </div>
  );
}