// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.

// @ts-check
/// <reference path="../../core/lib.deno_core.d.ts" />
/// <reference path="../web/internal.d.ts" />
/// <reference path="../web/lib.deno_web.d.ts" />
/// <reference path="./lib.deno_webgpu.d.ts" />

import { primordials } from "ext:core/mod.js";
import {
  op_webgpu_surface_configure,
  op_webgpu_surface_create,
  op_webgpu_surface_get_current_texture,
  op_webgpu_surface_present,
} from "ext:core/ops";
const {
  ObjectPrototypeIsPrototypeOf,
  Symbol,
  SymbolFor,
  TypeError,
} = primordials;

import * as webidl from "ext:deno_webidl/00_webidl.js";
import { createFilteredInspectProxy } from "ext:deno_console/01_console.js";
import { loadWebGPU } from "ext:deno_webgpu/00_init.js";

const _surfaceRid = Symbol("[[surfaceRid]]");
const _configuration = Symbol("[[configuration]]");
const _canvas = Symbol("[[canvas]]");
const _currentTexture = Symbol("[[currentTexture]]");
const _present = Symbol("[[present]]");
const _dim = Symbol("[[dimensions]]");

class GPUCanvasContext {
  /** @type {number} */
  [_surfaceRid];
  [_configuration];
  [_canvas];
  /** @type {GPUTexture | undefined} */
  [_currentTexture];
  [_dim];

  get canvas() {
    webidl.assertBranded(this, GPUCanvasContextPrototype);
    return this[_canvas];
  }

  constructor() {
    webidl.illegalConstructor();
  }

  configure(configuration) {
    webidl.assertBranded(this, GPUCanvasContextPrototype);
    const prefix = "Failed to execute 'configure' on 'GPUCanvasContext'";
    webidl.requiredArguments(arguments.length, 1, { prefix });
    configuration = webidl.converters.GPUCanvasConfiguration(configuration, {
      prefix,
      context: "Argument 1",
    });

    const { _device, assertDevice } = loadWebGPU();
    this[_device] = configuration.device[_device];
    this[_configuration] = configuration;
    const device = assertDevice(this, {
      prefix,
      context: "configuration.device",
    });

    const { err } = op_webgpu_surface_configure({
      surfaceRid: this[_surfaceRid],
      deviceRid: device.rid,
      format: configuration.format,
      viewFormats: configuration.viewFormats,
      usage: configuration.usage,
      width: this[_dim].width,
      height: this[_dim].height,
      alphaMode: configuration.alphaMode,
    });

    device.pushError(err);
  }

  unconfigure() {
    const { _device } = loadWebGPU();

    webidl.assertBranded(this, GPUCanvasContextPrototype);

    this[_configuration] = null;
    this[_device] = null;
  }

  getCurrentTexture() {
    webidl.assertBranded(this, GPUCanvasContextPrototype);
    const prefix =
      "Failed to execute 'getCurrentTexture' on 'GPUCanvasContext'";

    if (this[_configuration] === null) {
      throw new DOMException("Context is not configured", "InvalidStateError");
    }
    const { createGPUTexture, assertDevice } = loadWebGPU();

    const device = assertDevice(this, { prefix, context: "this" });

    if (this[_currentTexture]) {
      return this[_currentTexture];
    }

    const { rid } = op_webgpu_surface_get_current_texture(
      device.rid,
      this[_surfaceRid],
    );

    const texture = createGPUTexture(
      {
        size: {
          width: this[_dim].width,
          height: this[_dim].height,
          depthOrArrayLayers: 1,
        },
        mipLevelCount: 1,
        sampleCount: 1,
        dimension: "2d",
        format: this[_configuration].format,
        usage: this[_configuration].usage,
      },
      device,
      rid,
    );
    device.trackResource(texture);
    this[_currentTexture] = texture;
    return texture;
  }

  // Required to present the texture; browser don't need this.
  [_present]() {
    const { assertDevice } = loadWebGPU();

    webidl.assertBranded(this, GPUCanvasContextPrototype);
    const prefix = "Failed to execute 'present' on 'GPUCanvasContext'";
    const device = assertDevice(this[_currentTexture], {
      prefix,
      context: "this",
    });
    op_webgpu_surface_present(device.rid, this[_surfaceRid]);
    this[_currentTexture].destroy();
    this[_currentTexture] = undefined;
  }

  [SymbolFor("Deno.privateCustomInspect")](inspect, inspectOptions) {
    return inspect(
      createFilteredInspectProxy({
        object: this,
        evaluate: ObjectPrototypeIsPrototypeOf(GPUCanvasContextPrototype, this),
        keys: [
          "canvas",
        ],
      }),
      inspectOptions,
    );
  }
}
const GPUCanvasContextPrototype = GPUCanvasContext.prototype;

function createCanvasContext(options) {
  // lazy load webgpu if needed
  const canvasContext = webidl.createBranded(GPUCanvasContext);
  canvasContext[_surfaceRid] = options.surfaceRid;
  canvasContext[_canvas] = options.canvas;
  canvasContext[_dim] = { width: options.width, height: options.height };

  return canvasContext;
}

// External webgpu surfaces

// TODO(@littledivy): This will extend `OffscreenCanvas` when we add it.
class UnsafeWindowSurface {
  #ctx;
  #surfaceRid;
  #options;

  constructor(options) {
    if (typeof options !== "object") {
      throw new TypeError("options must be provided.");
    }
    if (
      typeof options.width !== "number" || typeof options.height !== "number"
    ) {
      throw new TypeError("width and height must be provided.");
    }

    this.#surfaceRid = op_webgpu_surface_create(
      options.system,
      options.windowHandle,
      options.displayHandle,
    );
    this.#options = options;
  }

  getContext(context) {
    if (context !== "webgpu") {
      throw new TypeError("Only 'webgpu' context is supported");
    }
    this.#ctx = createCanvasContext({
      surfaceRid: this.#surfaceRid,
      ...this.#options,
    });
    return this.#ctx;
  }

  present() {
    this.#ctx[_present]();
  }
}

export { GPUCanvasContext, UnsafeWindowSurface };