import { trackCollectable } from "./debug.js";
import { objectId } from "./shared.js";
import type { GpuContext } from "./types.js";

/**
 * Attachment formats a bundle is recorded against — a plain
 * GPURenderBundleEncoderDescriptor. Use `ctx.format` in `colorFormats` (and
 * `ctx.depthStencilFormat`) when the bundle targets the canvas.
 */
export type RenderBundleFormats = GPURenderBundleEncoderDescriptor;

/**
 * Record a reusable render bundle. The callback receives a
 * GPURenderBundleEncoder supporting setPipeline/setBindGroup/draw calls;
 * executing the finished bundle replays them with near-zero CPU cost.
 *
 * Use `ctx.format`/`ctx.depthStencilFormat` when the bundle targets the canvas.
 *
 * ```js
 * const bundle = gpu.createRenderBundle(
 *   ctx,
 *   {
 *     colorFormats: [ctx.format],
 *     depthStencilFormat: ctx.depthStencilFormat,
 *   },
 *   (encoder) => {
 *     encoder.setPipeline(pipeline);
 *     // ...
 *     encoder.drawIndexed(count);
 *   },
 * );
 * // later, inside a matching render pass:
 * pass.executeBundles([bundle]);
 * ```
 */
export function createRenderBundle(
  ctx: GpuContext,
  formats: RenderBundleFormats,
  record: (encoder: GPURenderBundleEncoder) => void,
): GPURenderBundle {
  const label = formats.label ?? "pex-gpu bundle";
  const encoder = ctx.device.createRenderBundleEncoder({
    ...formats,
    sampleCount: formats.sampleCount ?? 1,
    label,
  });
  record(encoder);
  const bundle = encoder.finish({ label });
  trackCollectable(ctx.device, "renderBundles", bundle, {
    id: objectId(bundle),
    label,
    bytes: 0,
  });
  return bundle;
}