const SSH_CMD = "/usr/bin/ssh amixer@knacki.info"

function sshCmd(cmd) {
	var cmdString = (SSH_CMD +' ' +cmd),
		cmd = cmdString.split(' ');
	return require('child_process').spawnSync(cmd[0], cmd.splice(1)).stdout.toString("utf-8");
}

function sshSetVolume(controlName, status) {
	sshCmd("mixSet " +status +" " +controlName);
}

function isChannelEnabled(line) {
	var percent = (/\[([0-9]+)%\]/).exec(line),
		state = (/\'([A-Za-z]+)\'/).exec(line);
	if (percent)
		return Number.parseInt(percent[1]) > 0;
	if (state)
		return state[1] === "Enabled";
	return false;
}

function sshGetVolume(controlName, channelList) {
	var output = sshCmd("mixGet " +controlName).split("\n");
	for (var i =0, len =output.length; i < len; ++i)
		for (var j =0, channelLen =channelList.length; j < channelLen; ++j) {
			var pos = output[i].indexOf(channelList[j] +":");
			if (pos >= 0 && isChannelEnabled(output[i].substr(pos +channelList[j].length +1)))
				return true;
		}
	return false;
}

function GenerateVolume(controlName) {
	return {
		on: function() { sshSetVolume(controlName, "100%") },
		off: function() { sshSetVolume(controlName, "0%") },
		get: function() { return sshGetVolume(controlName, [ "Front Left", "Front Right" ]); }
	};
}

function GenerateToggle(controlName) {
	return {
		on: function() { sshSetVolume(controlName, "Enabled") },
		off: function() { sshSetVolume(controlName, "Disabled") },
		get: function() { return sshGetVolume(controlName, [ "Item0" ]); }
	};
}

const inputs = {};

(function() {
	var inputConfig = require('./config.js').ALSA_INPUT;
	for (var i in inputConfig.volume)
		inputs[i] = GenerateVolume(inputConfig.volume[i]);
	for (var i in inputConfig.toggle)
		inputs[i] = GenerateToggle(inputConfig.toggle[i]);
})();

module.exports.init = function() {
	require("./outputs.js").registerOutput("alsa", {
		name: "PC Speaker",
		getInputs: function() {
			var speakerInputs = {};
			for (var i in inputs)
				speakerInputs[i] = inputs[i].get();
			return speakerInputs;
		},
		setState: function(inputId, state) {
			var input = inputs[inputId];
			if (input === undefined)
				return false;
			state ? input.on() : input.off();
			return true;
		},
		volumeControl: false
	});
}