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import { CanvasRenderingContext2D } from "./context2d.ts";import ffi, { cstr, getBuffer } from "./ffi.ts";import { ColorSpace } from "./image.ts";
const {  sk_canvas_create,  sk_canvas_destroy,  sk_canvas_save,  sk_canvas_read_pixels,  sk_canvas_encode_image,  sk_data_free,  sk_canvas_get_context,} = ffi;
const CANVAS_FINALIZER = new FinalizationRegistry((ptr: Deno.PointerValue) => {  sk_canvas_destroy(ptr);});
enum CFormat {  png = 0,  jpeg = 1,  webp = 2,}
export type ImageFormat = keyof typeof CFormat;
const OUT_SIZE = new Uint32Array(1);const OUT_SIZE_PTR = new Uint8Array(OUT_SIZE.buffer);const OUT_DATA = new BigUint64Array(1);const OUT_DATA_PTR = new Uint8Array(OUT_DATA.buffer);
const SK_DATA_FINALIZER = new FinalizationRegistry(  (ptr: Deno.PointerValue) => {    sk_data_free(ptr);  },);
/** * Canvas is an offscreen surface that can be drawn to. * * Internally it uses Skia's `SkSurface` and raster backend. * * API is mostly compatible with the Web's `OffscreenCanvas` API, * however we also have some non-standard methods such as `save`. * * @link https://developer.mozilla.org/en-US/docs/Web/API/Canvas_API */export class Canvas {  #ptr: Deno.PointerValue;  #width: number;  #height: number;  #pixels: Uint8Array;
  get _unsafePointer() {    return this.#ptr;  }
  /** Zero-copy pixels buffer that gets drawn into */  get pixels() {    return this.#pixels;  }
  get width() {    return this.#width;  }
  get height() {    return this.#height;  }
  constructor(width: number, height: number) {    this.#pixels = new Uint8Array(width * height * 4);    this.#ptr = sk_canvas_create(      width,      height,      this.#pixels,    );    if (this.#ptr === 0) {      throw new Error("Failed to create canvas");    }    CANVAS_FINALIZER.register(this, this.#ptr);    this.#width = width;    this.#height = height;  }
  /**   * Save the canvas image to a file encoded in specified format   * and quality.   *   * Quality is a factor between 0 and 100, where 100 is the best quality.   * It represents different factors for different formats.   */  save(path: string, format: ImageFormat = "png", quality = 100) {    if (!sk_canvas_save(this.#ptr, cstr(path), CFormat[format], quality)) {      throw new Error("Failed to save canvas");    }  }
  /**   * Encode the canvas image into a buffer in specified format   * and quality.   */  encode(format: ImageFormat = "png", quality = 100) {    const bufptr = sk_canvas_encode_image(      this.#ptr,      CFormat[format],      quality,      OUT_SIZE_PTR,      OUT_DATA_PTR,    );
    if (bufptr === 0) {      throw new Error("Failed to encode canvas");    }
    const size = OUT_SIZE[0];    const ptr = OUT_DATA[0];    const buffer = new Uint8Array(getBuffer(bufptr, size));    SK_DATA_FINALIZER.register(buffer, ptr);    return buffer;  }
  /**   * Read pixels from the canvas into a buffer.   */  readPixels(    x: number = 0,    y: number = 0,    width?: number,    height?: number,    into?: Uint8Array,    colorSpace: ColorSpace = "srgb",  ) {    width = width ?? this.#width;    height = height ?? this.#height;    const pixels = into ?? new Uint8Array(width * height * 4);    sk_canvas_read_pixels(      this.#ptr,      x,      y,      width,      height,      pixels,      colorSpace === "srgb" ? 0 : 1,    );    return pixels;  }
  getContext(type: "2d"): CanvasRenderingContext2D;  getContext(type: string): CanvasRenderingContext2D | null {    switch (type) {      case "2d": {        const ptr = sk_canvas_get_context(this.#ptr);        return new CanvasRenderingContext2D(this, ptr);      }      default:        return null;    }  }}
/** * Creates a new canvas with the given dimensions. */export function createCanvas(width: number, height: number) {  return new Canvas(width, height);}