// Copyright 2018 the Deno authors. All rights reserved. MIT license. import * as base64 from "base64-js"; import { DenoError, ErrorKind } from "./errors"; /** Decodes a string of data which has been encoded using base-64. */ export function atob(s: string): string { const rem = s.length % 4; // base64-js requires length exactly times of 4 if (rem > 0) { s = s.padEnd(s.length + (4 - rem), "="); } let byteArray; try { byteArray = base64.toByteArray(s); } catch (_) { throw new DenoError( ErrorKind.InvalidInput, "The string to be decoded is not correctly encoded" ); } let result = ""; for (let i = 0; i < byteArray.length; i++) { result += String.fromCharCode(byteArray[i]); } return result; } /** Creates a base-64 ASCII string from the input string. */ export function btoa(s: string): string { const byteArray = []; for (let i = 0; i < s.length; i++) { const charCode = s[i].charCodeAt(0); if (charCode > 0xff) { throw new DenoError( ErrorKind.InvalidInput, "The string to be encoded contains characters " + "outside of the Latin1 range." ); } byteArray.push(charCode); } const result = base64.fromByteArray(Uint8Array.from(byteArray)); return result; } // @types/text-encoding relies on lib.dom.d.ts for some interfaces. We do not // want to include lib.dom.d.ts (due to size) into deno's global type scope. // Therefore this hack: add a few of the missing interfaces in // @types/text-encoding to the global scope before importing. declare global { type BufferSource = ArrayBufferView | ArrayBuffer; interface TextDecodeOptions { stream?: boolean; } interface TextDecoderOptions { fatal?: boolean; ignoreBOM?: boolean; } interface TextDecoder { readonly encoding: string; readonly fatal: boolean; readonly ignoreBOM: boolean; decode(input?: BufferSource, options?: TextDecodeOptions): string; } } export { TextEncoder, TextDecoder } from "text-encoding";