import { memo } from "react";
import { Handle, Position, type NodeProps } from "reactflow";
import type { RFData } from "../layout";

// One pipeline stage on the map. Color encodes live state; a badge shows the
// live task count; gated (P3/inert) nodes render dimmed with a tag. ARIA role +
// label keep the map reachable for screen readers / keyboard users.
function MapNodeImpl({ data }: NodeProps<RFData>) {
  const { meta, state, count, dimmed, onPath, loopBackTo } = data;
  const cls = [
    "node",
    `state-${state}`,
    meta.gated ? "gated" : "",
    dimmed ? "dimmed" : "",
    onPath ? "on-path" : "",
  ]
    .filter(Boolean)
    .join(" ");
  const canLoop = loopBackTo.length > 0;

  return (
    <div
      className={cls}
      role="group"
      aria-label={`${meta.label} stage, ${state}, ${count} task${count === 1 ? "" : "s"}`}
      tabIndex={0}
    >
      <Handle type="target" position={Position.Left} />
      <div className="node-label">
        {meta.label}
        {meta.kind === "gate" && (
          <span className="gate-pip" title="human gate" aria-hidden>
            ⛋
          </span>
        )}
        {canLoop && (
          <span
            className="loop-chip"
            title={`can send work back to ${loopBackTo.join(", ")}`}
            aria-label={`can send work back to ${loopBackTo.join(", ")}`}
          >
            ↺
          </span>
        )}
      </div>
      <div className="node-agent">{meta.agent}</div>
      {count > 0 && (
        <span className="node-count" aria-hidden>
          {count}
        </span>
      )}
      {meta.gated && <span className="node-gated-tag">inert</span>}
      <Handle type="source" position={Position.Right} />
    </div>
  );
}

export const MapNode = memo(MapNodeImpl);