import type { BackendInfo, RunRequest, RunResult, Runner } from "./types";
import { numblVersion } from "./execute";
import { executeRequest, type GpuProvider } from "./executeGpu";

/**
 * Runs numbl in the current Node process. Used by tests and scripts; cannot
 * cancel. Pass `gpu` to run the ported time loop on a WebGPU device (the
 * optional `webgpu` package, Google Dawn, provides one under Node).
 */
export class NodeRunner implements Runner {
  private readonly info: BackendInfo = {
    engine: "numbl",
    version: numblVersion(),
    optimization: "1",
    host: "node",
  };
  readonly backend = Promise.resolve(this.info);
  private readonly gpu?: GpuProvider;

  constructor(opts: { gpu?: GpuProvider } = {}) {
    this.gpu = opts.gpu;
  }

  run(req: RunRequest, onOutput?: (text: string) => void): Promise<RunResult> {
    return executeRequest(req, this.info, onOutput, this.gpu);
  }
  cancel(): void {
    /* synchronous host: nothing in flight between awaits */
  }
  dispose(): void {
    /* nothing to release */
  }
}