node-mpv-2/lib/mpv/_commands.js

A Node module for MPV

'use strict';

const util = require('../util');

const commands = {
	// will send a get request for the specified property
	// if no idea is provided this will return a promise
	// if an id is provied the answer will come via a 'getrequest' event containing the id and data
	getProperty: function(property){
		return this.socket.getProperty(property);
	},
	// set a property specified by the mpv API
	setProperty: function(property, value){
		return this.socket.setProperty(property, value);
	},
	// sets all properties defined in the properties Json object
	setMultipleProperties: function(properties){
		return new Promise((resolve, reject) => {
			// check if the player is running
			if(this.running){
				// list of all promises
				let promises = []
				// add all promises  to the list
				Object.keys(properties).forEach((property) => {
					promises.push(this.socket.setProperty(property, properties[property]));
				});
				// return the promise all object
				resolve(Promise.all(promises));
			}
			// reject if MPV is not running
			else{
				return reject(
					this.errorHandler.errorMessage(8, util.getCaller())
				);
			}
		})
	},
	// adds the value to the property
	addProperty: function(property, value){
		return this.socket.addProperty(property, value);
	},
	// multiplies the specified property by the value
	multiplyProperty: function(property, value) {
		return this.socket.multiplyProperty(property, value);
	},
	// cycles a arbitrary property
	cycleProperty: function(property){
		return this.socket.cycleProperty(property);
	},
	// send a command with arguments to mpv
	command: function(command, args){
		return this.socket.command(command, args);
	},
	// sends a command specified by a JSON object to mpv
	commandJSON: function(command){
		return this.socket.freeCommand(JSON.stringify(command));
	},
	// send a freely writeable command to mpv.
	// the required trailing \n will be added
	freeCommand: function(command){
		return this.socket.freeCommand(command);
	},

	// observe a property for changes
	// will be added to event for property changes
	observeProperty: function(property) {
		// create the id assigned with this property
		// +1 because time-pos (which has the id 0) is not included in this object
		const prop_id = Object.keys(this.observedProperties).length+1;
		// store the id into the hash map, such that it can be retrieved later if
		// the property should be unobserved
		this.observedProperties[property] = prop_id;
		return this.socket.command('observe_property', [prop_id, property]);
			
	},
	// stop observing a property
	unobserveProperty: function(property) {
		// retrieve the id associated with this property
		const prop_id = this.observedProperties[property];
		delete this.observedProperties[prop_id];
		return this.socket.command('unobserve_property', [prop_id]);
	}
}

module.exports = commands;