Add swww support (sindresorhus#94)

Co-authored-by: Sindre Sorhus <[email protected]>

Author: 2 people

source/linux/background-managers/index.js

@@ -13,5 +13,6 @@ module.exports = {
 	qdbus: require('./qdbus.js'),
 	setroot: require('./setroot.js'),
 	xfconfquery: require('./xfconf-query.js'),
-	swaybg: require('./swaybg.js')
+	swaybg: require('./swaybg.js'),
+	swww: require('./swww.js')
 };

source/linux/background-managers/swww.js

@@ -0,0 +1,27 @@
+'use strict';
+const {commandExists, execFile} = require('../util.js');
+
+exports.isAvailable = () => commandExists('swww');
+
+async function initialize() {
+	try {
+		await execFile('swww', ['init']);
+	} catch (error) {
+		if (error.stderr.includes('There seems to already be another instance running')) {
+			return;
+		}
+
+		throw new Error(`Failed to set image for swww: ${error.stderr}`);
+	}
+};
+
+exports.get = async () => {
+	await initialize();
+	const {stdout: query} = await execFile('swww', ['query']);
+	return query.slice(query.indexOf('/'), query.indexOf('\n'));
+};
+
+exports.set = async imagePath => {
+	await initialize();
+	await execFile('swww', ['img', imagePath]);
+};