Add support of typescript (#738)

Author: umidjon-2231

type.d.ts

@@ -0,0 +1,49 @@
+declare module "html2pdf.js" {
+  interface Html2PdfOptions {
+    margin?: number | [number, number] | [number, number, number, number];
+    filename?: string;
+    image?: {
+      type?: "jpeg" | "png" | "webp";
+      quality?: number;
+    };
+    enableLinks?: boolean;
+    html2canvas?: object;
+    jsPDF?: {
+      unit?: string;
+      format?: string | [number, number];
+      orientation?: "portrait" | "landscape";
+    };
+  }
+
+  interface Html2PdfWorker {
+    from(src: HTMLElement | string | HTMLCanvasElement | HTMLImageElement): this;
+    to(target: "container" | "canvas" | "img" | "pdf"): this;
+    toContainer(): this;
+    toCanvas(): this;
+    toImg(): this;
+    toPdf(): this;
+    output(type?: string, options?: any, src?: "pdf" | "img"): Promise<any>;
+    outputPdf(type?: string, options?: any): Promise<any>;
+    outputImg(type?: string, options?: any): Promise<any>;
+    save(filename?: string): Promise<void>;
+    set(options: Html2PdfOptions): this;
+    get(key: string, cbk?: (value: any) => void): Promise<any>;
+    then<T>(onFulfilled?: (value: any) => T | PromiseLike<T>, onRejected?: (reason: any) => any): Promise<T>;
+    thenCore<T>(onFulfilled?: (value: any) => T | PromiseLike<T>, onRejected?: (reason: any) => any): Promise<T>;
+    thenExternal<T>(onFulfilled?: (value: any) => T | PromiseLike<T>, onRejected?: (reason: any) => any): Promise<T>;
+    catch<T>(onRejected?: (reason: any) => T | PromiseLike<T>): Promise<T>;
+    catchExternal<T>(onRejected?: (reason: any) => T | PromiseLike<T>): Promise<T>;
+    error(msg: string): void;
+  }
+
+  interface Html2PdfStatic {
+    (): Html2PdfWorker;
+    new (): Html2PdfWorker;
+    (element: HTMLElement, options?: Html2PdfOptions): Promise<void>;
+    new (element: HTMLElement, options?: Html2PdfOptions): Promise<void>;
+    Worker: new () => Html2PdfWorker;
+  }
+
+  const html2pdf: Html2PdfStatic;
+  export default html2pdf;
+}