"use client";

import { useJobProgress } from "@/hooks/use-job-progress";
import type { StageStatus, RoutingDetail as RoutingDetailType } from "@/hooks/use-job-progress";

function StageIcon({ status }: { status: StageStatus["status"] }) {
  if (status === "completed")
    return (
      <span className="w-5 h-5 flex items-center justify-center rounded-full bg-green-100 text-green-600 text-xs shrink-0">
        ✓
      </span>
    );
  if (status === "failed")
    return (
      <span className="w-5 h-5 flex items-center justify-center rounded-full bg-red-100 text-red-600 text-xs shrink-0">
        ✗
      </span>
    );
  if (status === "active")
    return (
      <span className="w-5 h-5 flex items-center justify-center shrink-0">
        <svg className="animate-spin w-4 h-4 text-brand-600" viewBox="0 0 24 24" fill="none">
          <circle cx="12" cy="12" r="10" stroke="currentColor" strokeWidth="2" opacity="0.25" />
          <path d="M12 2a10 10 0 0 1 10 10" stroke="currentColor" strokeWidth="2" strokeLinecap="round" />
        </svg>
      </span>
    );
  return <span className="w-5 h-5 rounded-full border-2 border-gray-300 shrink-0" />;
}

function StageRow({ stage, error }: { stage: StageStatus; error?: string }) {
  return (
    <div className="flex items-start gap-3">
      <StageIcon status={stage.status} />
      <div className="flex-1 min-w-0">
        <p className={`text-sm font-medium ${stage.status === "pending" ? "text-gray-400" : "text-gray-900"}`}>
          {stage.label}
        </p>
        {stage.status === "active" && (
          <>
            <div className="w-full bg-gray-200 rounded-full h-1 mt-1.5">
              <div
                className="bg-brand-600 h-1 rounded-full transition-all duration-500"
                style={{ width: `${stage.pct}%` }}
              />
            </div>
            <p className="text-xs text-gray-500 mt-0.5 truncate">{stage.message}</p>
          </>
        )}
        {stage.status === "failed" && error && (
          <p className="text-xs text-red-600 mt-0.5">{error}</p>
        )}
      </div>
    </div>
  );
}

function RoutingGrid({ routingDetail }: { routingDetail: RoutingDetailType }) {
  const MODE_LABELS: Record<string, string> = {
    walking: "Walking",
    cycling: "Cycling",
    driving: "Driving",
    transit: "Transit",
  };
  const entries = Object.entries(routingDetail);
  if (entries.length === 0) return null;
  return (
    <div className="mt-2 space-y-1.5 pl-8">
      {entries.map(([mode, { done, total }]) => (
        <div key={mode} className="flex items-center gap-2">
          <span className="text-xs text-gray-500 w-14 shrink-0">{MODE_LABELS[mode] ?? mode}</span>
          <div className="flex-1 bg-gray-200 rounded-full h-1.5">
            <div
              className="bg-brand-500 h-1.5 rounded-full transition-all duration-500"
              style={{ width: total > 0 ? `${(done / total) * 100}%` : done > 0 ? "100%" : "0%" }}
            />
          </div>
          <span className="text-xs text-gray-400 w-10 text-right shrink-0">
            {total > 1 ? `${done}/${total}` : done >= 1 ? "done" : "…"}
          </span>
        </div>
      ))}
    </div>
  );
}

export function CityIngestProgress({
  jobId,
  className = "card max-w-lg",
}: {
  jobId: string | null;
  className?: string;
}) {
  const { stages, overall, error, routingDetail } = useJobProgress(jobId);

  if (!jobId) return null;

  type StageGroup =
    | { kind: "single"; stage: StageStatus }
    | { kind: "parallel"; stages: StageStatus[] };

  const groups: StageGroup[] = [];
  for (const stage of stages) {
    if (stage.parallelGroup) {
      const last = groups[groups.length - 1];
      if (last?.kind === "parallel" && last.stages[0].parallelGroup === stage.parallelGroup) {
        last.stages.push(stage);
      } else {
        groups.push({ kind: "parallel", stages: [stage] });
      }
    } else {
      groups.push({ kind: "single", stage });
    }
  }

  return (
    <div className={className}>
      <h2 className="text-lg font-semibold mb-6">Processing City Data</h2>

      <div className="space-y-4">
        {groups.map((group, gi) =>
          group.kind === "single" ? (
            <div key={group.stage.key}>
              <StageRow stage={group.stage} error={error} />
              {group.stage.key === "Computing scores" &&
                group.stage.status === "active" &&
                routingDetail && (
                  <RoutingGrid routingDetail={routingDetail} />
                )}
            </div>
          ) : (
            <div
              key={`group-${gi}`}
              className="rounded-lg border border-gray-200 bg-gray-50 p-3 space-y-3"
            >
              <p className="text-xs font-medium text-gray-400 uppercase tracking-wide">
                Running in parallel
              </p>
              {group.stages.map((s) => (
                <StageRow key={s.key} stage={s} error={error} />
              ))}
            </div>
          ),
        )}
      </div>

      {overall === "completed" && (
        <div className="mt-6 p-4 bg-green-50 rounded-lg text-green-800 text-sm">
          ✓ City ingestion complete!{" "}
          <a href="/admin" className="underline font-medium">
            Return to dashboard
          </a>{" "}
          or{" "}
          <a href="/" className="underline font-medium">
            view on map
          </a>
          .
        </div>
      )}

      {overall === "failed" && (
        <div className="mt-6 p-4 bg-red-50 rounded-lg text-red-800 text-sm">
          ✗ Ingestion failed: {error}{" "}
          <a href="/admin" className="underline">
            Return to dashboard
          </a>
          .
        </div>
      )}
    </div>
  );
}