import Badge from "@/components/ui/Badge";
import { fmt } from "@/lib/data";
import type { DatasetInfo } from "@/lib/types";
import HourBar from "./HourBar";

export interface SplitsTableProps {
  /** Frozen split inventory of a live dataset. */
  splits: NonNullable<DatasetInfo["splits"]>;
  /** Dataset name for the accessible caption, e.g. "ViMedCSS". */
  datasetName?: string;
}

const ROWS: ReadonlyArray<{
  key: keyof NonNullable<DatasetInfo["splits"]>;
  name: string;
  tone: "muted" | "accent" | "accent-soft";
  badge?: { label: string; variant: "accent" | "outline" };
  role: string;
}> = [
  {
    key: "train",
    name: "Train",
    tone: "muted",
    role: "Adaptation corpus — Track C systems may train on this split and nothing else.",
  },
  {
    key: "valid",
    name: "Valid",
    tone: "muted",
    role: "Hyperparameter tuning and checkpoint selection. Never reported as a result.",
  },
  {
    key: "test",
    name: "Test",
    tone: "accent",
    badge: { label: "Primary", variant: "accent" },
    role: "The primary leaderboard — every headline number on the home page is scored here.",
  },
  {
    key: "hard",
    name: "Hard",
    tone: "accent-soft",
    badge: { label: "Generalization", variant: "outline" },
    role: "Rare and unseen terms, disjoint from Train — the generalization leaderboard.",
  },
];

/** Dataset split table with proportional hour-bars and role captions. */
export default function SplitsTable({ splits, datasetName }: SplitsTableProps) {
  const totalHours = ROWS.reduce((sum, r) => sum + splits[r.key].hours, 0);

  return (
    <div className="hairline spotlight-row depth-1 overflow-x-auto rounded-sm bg-surface">
      <table className="w-full min-w-[680px] border-collapse text-sm">
        <caption className="sr-only">
          {datasetName ?? "Dataset"} splits: hours, utterances, share of total
          audio, and the role of each split
        </caption>
        <thead>
          <tr className="hairline-b text-left">
            <th
              scope="col"
              className="num px-4 py-3 text-[11px] font-normal uppercase tracking-[0.14em] text-muted"
            >
              Split
            </th>
            <th
              scope="col"
              className="num px-4 py-3 text-right text-[11px] font-normal uppercase tracking-[0.14em] text-muted"
            >
              Hours
            </th>
            <th
              scope="col"
              className="num px-4 py-3 text-right text-[11px] font-normal uppercase tracking-[0.14em] text-muted"
            >
              Utterances
            </th>
            <th
              scope="col"
              className="num px-4 py-3 text-[11px] font-normal uppercase tracking-[0.14em] text-muted"
            >
              Share of audio
            </th>
            <th
              scope="col"
              className="num px-4 py-3 text-[11px] font-normal uppercase tracking-[0.14em] text-muted"
            >
              Role
            </th>
          </tr>
        </thead>
        <tbody>
          {ROWS.map((row, i) => {
            const s = splits[row.key];
            const share = s.hours / totalHours;
            return (
              <tr
                key={row.key}
                className={i < ROWS.length - 1 ? "hairline-b align-top" : "align-top"}
              >
                <th
                  scope="row"
                  className="whitespace-nowrap px-4 py-3.5 text-left font-medium text-text"
                >
                  <span className="inline-flex items-center gap-2">
                    {row.name}
                    {row.badge && (
                      <Badge variant={row.badge.variant}>{row.badge.label}</Badge>
                    )}
                  </span>
                </th>
                <td className="num whitespace-nowrap px-4 py-3.5 text-right text-text">
                  {fmt(s.hours)}
                  <span className="text-muted"> h</span>
                </td>
                <td className="num whitespace-nowrap px-4 py-3.5 text-right text-text">
                  {s.utts.toLocaleString("en-US")}
                </td>
                <td className="px-4 py-3.5">
                  <div className="flex items-center gap-2.5">
                    <HourBar share={share} tone={row.tone} className="w-24 md:w-32" />
                    <span className="num text-[11px] text-muted">
                      {(share * 100).toFixed(1)}%
                    </span>
                  </div>
                </td>
                <td className="min-w-[16rem] px-4 py-3.5 text-[13px] leading-relaxed text-muted">
                  {row.role}
                </td>
              </tr>
            );
          })}
        </tbody>
      </table>
    </div>
  );
}