import { memory } from './types'; const B64 = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/='; /** Encode an array of bytes in base64. */ export function base64_encode(data: null | undefined): undefined; export function base64_encode(data: memory): string; export function base64_encode(data: memory | null | undefined): string | undefined { // Twacked by Will Scullin to handle arrays of 'bytes' // http://kevin.vanzonneveld.net // + original by: Tyler Akins (http://rumkin.com) // + improved by: Bayron Guevara // + improved by: Thunder.m // + improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net) // + bugfixed by: Pellentesque Malesuada // + improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net) // - depends on: utf8_encode // * example 1: base64_encode('Kevin van Zonneveld'); // * returns 1: 'S2V2aW4gdmFuIFpvbm5ldmVsZA==' // mozilla has this native // - but breaks in 2.0.0.12! //if (typeof this.window['atob'] == 'function') { // return atob(data); //} let o1, o2, o3, h1, h2, h3, h4, bits, i = 0, ac = 0, enc=''; const tmp_arr = []; if (!data) { return undefined; } do { // pack three octets into four hexets o1 = data[i++]; o2 = data[i++]; o3 = data[i++]; bits = o1<<16 | o2<<8 | o3; h1 = bits>>18 & 0x3f; h2 = bits>>12 & 0x3f; h3 = bits>>6 & 0x3f; h4 = bits & 0x3f; // use hexets to index into b64, and append result to encoded string tmp_arr[ac++] = B64.charAt(h1) + B64.charAt(h2) + B64.charAt(h3) + B64.charAt(h4); } while (i < data.length); enc = tmp_arr.join(''); switch (data.length % 3) { case 1: enc = enc.slice(0, -2) + '=='; break; case 2: enc = enc.slice(0, -1) + '='; break; } return enc; } /** Returns undefined if the input is null or undefined. */ export function base64_decode(data: null | undefined): undefined; /** Returns an array of bytes from the given base64-encoded string. */ export function base64_decode(data: string): memory; /** Returns an array of bytes from the given base64-encoded string. */ export function base64_decode(data: string | null | undefined): memory | undefined { // Twacked by Will Scullin to handle arrays of 'bytes' // http://kevin.vanzonneveld.net // + original by: Tyler Akins (http://rumkin.com) // + improved by: Thunder.m // + input by: Aman Gupta // + improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net) // + bugfixed by: Onno Marsman // + bugfixed by: Pellentesque Malesuada // + improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net) // + input by: Brett Zamir (http://brett-zamir.me) // + bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net) // - depends on: utf8_decode // * example 1: base64_decode('S2V2aW4gdmFuIFpvbm5ldmVsZA=='); // * returns 1: 'Kevin van Zonneveld' // mozilla has this native // - but breaks in 2.0.0.12! //if (typeof this.window['btoa'] == 'function') { // return btoa(data); //} let o1, o2, o3, h1, h2, h3, h4, bits, i = 0, ac = 0; const tmp_arr = []; if (!data) { return undefined; } do { // unpack four hexets into three octets using index points in B64 h1 = B64.indexOf(data.charAt(i++)); h2 = B64.indexOf(data.charAt(i++)); h3 = B64.indexOf(data.charAt(i++)); h4 = B64.indexOf(data.charAt(i++)); bits = h1<<18 | h2<<12 | h3<<6 | h4; o1 = bits>>16 & 0xff; o2 = bits>>8 & 0xff; o3 = bits & 0xff; tmp_arr[ac++] = o1; if (h3 != 64) { tmp_arr[ac++] = o2; } if (h4 != 64) { tmp_arr[ac++] = o3; } } while (i < data.length); return new Uint8Array(tmp_arr); } const DATA_URL_PREFIX = 'data:application/octet-stream;base64,'; export function base64_json_parse(json: string) { const reviver = (_key: string, value: any) => { if (typeof value ==='string' && value.startsWith(DATA_URL_PREFIX)) { return base64_decode(value.slice(DATA_URL_PREFIX.length)); } return value; }; return JSON.parse(json, reviver); } export function base64_json_stringify(json: any) { const replacer = (_key: string, value: any) => { if (value instanceof Uint8Array) { return DATA_URL_PREFIX + base64_encode(value); } return value; }; return JSON.stringify(json, replacer); }