send/app/fileReceiver.js
2018-02-21 14:58:41 -08:00

121 lines
3 KiB
JavaScript

import Nanobus from 'nanobus';
import Keychain from './keychain';
import { bytes } from './utils';
import { metadata, downloadFile } from './api';
export default class FileReceiver extends Nanobus {
constructor(fileInfo) {
super('FileReceiver');
this.keychain = new Keychain(fileInfo.secretKey, fileInfo.nonce);
if (fileInfo.requiresPassword) {
this.keychain.setPassword(fileInfo.password, fileInfo.url);
}
this.fileInfo = fileInfo;
this.reset();
}
get progressRatio() {
return this.progress[0] / this.progress[1];
}
get progressIndefinite() {
return this.state !== 'downloading';
}
get sizes() {
return {
partialSize: bytes(this.progress[0]),
totalSize: bytes(this.progress[1])
};
}
cancel() {
this.cancelled = true;
if (this.fileDownload) {
this.fileDownload.cancel();
}
}
reset() {
this.fileDownload = null;
this.msg = 'fileSizeProgress';
this.state = 'initialized';
this.progress = [0, 1];
this.cancelled = false;
}
async getMetadata() {
const meta = await metadata(this.fileInfo.id, this.keychain);
if (meta) {
this.keychain.setIV(meta.iv);
this.fileInfo.name = meta.name;
this.fileInfo.type = meta.type;
this.fileInfo.iv = meta.iv;
this.fileInfo.size = meta.size;
this.state = 'ready';
return;
}
this.state = 'invalid';
return;
}
async download() {
this.state = 'downloading';
this.emit('progress', this.progress);
try {
const download = await downloadFile(this.fileInfo.id, this.keychain);
download.onprogress = p => {
this.progress = p;
this.emit('progress', p);
};
this.fileDownload = download;
const ciphertext = await download.result;
this.fileDownload = null;
this.msg = 'decryptingFile';
this.state = 'decrypting';
this.emit('decrypting');
const plaintext = await this.keychain.decryptFile(ciphertext);
if (this.cancelled) {
throw new Error(0);
}
await saveFile({
plaintext,
name: decodeURIComponent(this.fileInfo.name),
type: this.fileInfo.type
});
this.msg = 'downloadFinish';
this.state = 'complete';
return;
} catch (e) {
this.state = 'invalid';
throw e;
}
}
}
async function saveFile(file) {
return new Promise(function(resolve, reject) {
const reader = new FileReader();
const dataView = new DataView(file.plaintext);
const blob = new Blob([dataView], { type: file.type });
if (window.navigator.msSaveBlob) {
window.navigator.msSaveBlob(blob, file.name);
return resolve();
}
reader.addEventListener('loadend', function() {
if (reader.error) {
return reject(reader.error);
}
if (reader.result) {
const a = document.createElement('a');
a.href = reader.result;
a.download = file.name;
document.body.appendChild(a);
a.click();
}
resolve();
});
reader.readAsDataURL(blob);
});
}