asarfuckery/electronasar/ptb/browser/desktop-capturer.js

86 lines
3.2 KiB
JavaScript

'use strict';
const ipcMainUtils = require('@electron/internal/browser/ipc-main-internal-utils');
const { createDesktopCapturer } = process.electronBinding('desktop_capturer');
const eventBinding = process.electronBinding('event');
const deepEqual = (a, b) => JSON.stringify(a) === JSON.stringify(b);
let currentlyRunning = [];
ipcMainUtils.handle('ELECTRON_BROWSER_DESKTOP_CAPTURER_GET_SOURCES', (event, captureWindow, captureScreen, thumbnailSize, fetchWindowIcons) => {
const customEvent = eventBinding.createWithSender(event.sender);
event.sender.emit('desktop-capturer-get-sources', customEvent);
if (customEvent.defaultPrevented) {
return [];
}
const options = {
captureWindow,
captureScreen,
thumbnailSize,
fetchWindowIcons
};
for (const running of currentlyRunning) {
if (deepEqual(running.options, options)) {
// If a request is currently running for the same options
// return that promise
return running.getSources;
}
}
const getSources = new Promise((resolve, reject) => {
const stopRunning = () => {
// Remove from currentlyRunning once we resolve or reject
currentlyRunning = currentlyRunning.filter(running => running.options !== options);
};
const request = {
options,
resolve: (value) => {
stopRunning();
resolve(value);
},
reject: (err) => {
stopRunning();
reject(err);
},
capturer: createDesktopCapturer()
};
request.capturer.emit = createCapturerEmitHandler(request.capturer, request);
request.capturer.startHandling(captureWindow, captureScreen, thumbnailSize, fetchWindowIcons);
// If the WebContents is destroyed before receiving result, just remove the
// reference to resolve, emit and the capturer itself so that it never dispatches
// back to the renderer
event.sender.once('destroyed', () => {
request.resolve = null;
delete request.capturer.emit;
delete request.capturer;
stopRunning();
});
});
currentlyRunning.push({
options,
getSources
});
return getSources;
});
const createCapturerEmitHandler = (capturer, request) => {
return function handlEmitOnCapturer(event, name, sources, fetchWindowIcons) {
// Ensure that this capturer instance can only ever receive a single event
// if we get more than one it is a bug but will also cause strange behavior
// if we still try to handle it
delete capturer.emit;
if (name === 'error') {
const error = sources;
request.reject(error);
return;
}
const result = sources.map(source => {
return {
id: source.id,
name: source.name,
thumbnail: source.thumbnail.toDataURL(),
display_id: source.display_id,
appIcon: (fetchWindowIcons && source.appIcon) ? source.appIcon.toDataURL() : null
};
});
if (request.resolve) {
request.resolve(result);
}
};
};