Platform.js

//import //

var _elm_lang$core$Native_Platform = function() {


// PROGRAMS

function program(impl)
{
	return function(flagDecoder)
	{
		return function(object, moduleName)
		{
			object['worker'] = function worker(flags)
			{
				if (typeof flags !== 'undefined')
				{
					throw new Error(
						'The `' + moduleName + '` module does not need flags.\n'
						+ 'Call ' + moduleName + '.worker() with no arguments and you should be all set!'
					);
				}

				return initialize(
					impl.init,
					impl.update,
					impl.subscriptions,
					renderer
				);
			};
		};
	};
}

function programWithFlags(impl)
{
	return function(flagDecoder)
	{
		return function(object, moduleName)
		{
			object['worker'] = function worker(flags)
			{
				if (typeof flagDecoder === 'undefined')
				{
					throw new Error(
						'Are you trying to sneak a Never value into Elm? Trickster!\n'
						+ 'It looks like ' + moduleName + '.main is defined with `programWithFlags` but has type `Program Never`.\n'
						+ 'Use `program` instead if you do not want flags.'
					);
				}

				var result = A2(_elm_lang$core$Native_Json.run, flagDecoder, flags);
				if (result.ctor === 'Err')
				{
					throw new Error(
						moduleName + '.worker(...) was called with an unexpected argument.\n'
						+ 'I tried to convert it to an Elm value, but ran into this problem:\n\n'
						+ result._0
					);
				}

				return initialize(
					impl.init(result._0),
					impl.update,
					impl.subscriptions,
					renderer
				);
			};
		};
	};
}

function renderer(enqueue, _)
{
	return function(_) {};
}


// HTML TO PROGRAM

function htmlToProgram(vnode)
{
	var emptyBag = batch(_elm_lang$core$Native_List.Nil);
	var noChange = _elm_lang$core$Native_Utils.Tuple2(
		_elm_lang$core$Native_Utils.Tuple0,
		emptyBag
	);

	return _elm_lang$virtual_dom$VirtualDom$program({
		init: noChange,
		view: function(model) { return main; },
		update: F2(function(msg, model) { return noChange; }),
		subscriptions: function (model) { return emptyBag; }
	});
}


// INITIALIZE A PROGRAM

function initialize(init, update, subscriptions, renderer)
{
	// ambient state
	var managers = {};
	var updateView;

	// init and update state in main process
	var initApp = _elm_lang$core$Native_Scheduler.nativeBinding(function(callback) {
		var model = init._0;
		updateView = renderer(enqueue, model);
		var cmds = init._1;
		var subs = subscriptions(model);
		dispatchEffects(managers, cmds, subs);
		callback(_elm_lang$core$Native_Scheduler.succeed(model));
	});

	function onMessage(msg, model)
	{
		return _elm_lang$core$Native_Scheduler.nativeBinding(function(callback) {
			var results = A2(update, msg, model);
			model = results._0;
			updateView(model);
			var cmds = results._1;
			var subs = subscriptions(model);
			dispatchEffects(managers, cmds, subs);
			callback(_elm_lang$core$Native_Scheduler.succeed(model));
		});
	}

	var mainProcess = spawnLoop(initApp, onMessage);

	function enqueue(msg)
	{
		_elm_lang$core$Native_Scheduler.rawSend(mainProcess, msg);
	}

	var ports = setupEffects(managers, enqueue);

	return ports ? { ports: ports } : {};
}


// EFFECT MANAGERS

var effectManagers = {};

function setupEffects(managers, callback)
{
	var ports;

	// setup all necessary effect managers
	for (var key in effectManagers)
	{
		var manager = effectManagers[key];

		if (manager.isForeign)
		{
			ports = ports || {};
			ports[key] = manager.tag === 'cmd'
				? setupOutgoingPort(key)
				: setupIncomingPort(key, callback);
		}

		managers[key] = makeManager(manager, callback);
	}

	return ports;
}

function makeManager(info, callback)
{
	var router = {
		main: callback,
		self: undefined
	};

	var tag = info.tag;
	var onEffects = info.onEffects;
	var onSelfMsg = info.onSelfMsg;

	function onMessage(msg, state)
	{
		if (msg.ctor === 'self')
		{
			return A3(onSelfMsg, router, msg._0, state);
		}

		var fx = msg._0;
		switch (tag)
		{
			case 'cmd':
				return A3(onEffects, router, fx.cmds, state);

			case 'sub':
				return A3(onEffects, router, fx.subs, state);

			case 'fx':
				return A4(onEffects, router, fx.cmds, fx.subs, state);
		}
	}

	var process = spawnLoop(info.init, onMessage);
	router.self = process;
	return process;
}

function sendToApp(router, msg)
{
	return _elm_lang$core$Native_Scheduler.nativeBinding(function(callback)
	{
		router.main(msg);
		callback(_elm_lang$core$Native_Scheduler.succeed(_elm_lang$core$Native_Utils.Tuple0));
	});
}

function sendToSelf(router, msg)
{
	return A2(_elm_lang$core$Native_Scheduler.send, router.self, {
		ctor: 'self',
		_0: msg
	});
}


// HELPER for STATEFUL LOOPS

function spawnLoop(init, onMessage)
{
	var andThen = _elm_lang$core$Native_Scheduler.andThen;

	function loop(state)
	{
		var handleMsg = _elm_lang$core$Native_Scheduler.receive(function(msg) {
			return onMessage(msg, state);
		});
		return A2(andThen, loop, handleMsg);
	}

	var task = A2(andThen, loop, init);

	return _elm_lang$core$Native_Scheduler.rawSpawn(task);
}


// BAGS

function leaf(home)
{
	return function(value)
	{
		return {
			type: 'leaf',
			home: home,
			value: value
		};
	};
}

function batch(list)
{
	return {
		type: 'node',
		branches: list
	};
}

function map(tagger, bag)
{
	return {
		type: 'map',
		tagger: tagger,
		tree: bag
	}
}


// PIPE BAGS INTO EFFECT MANAGERS

function dispatchEffects(managers, cmdBag, subBag)
{
	var effectsDict = {};
	gatherEffects(true, cmdBag, effectsDict, null);
	gatherEffects(false, subBag, effectsDict, null);

	for (var home in managers)
	{
		var fx = home in effectsDict
			? effectsDict[home]
			: {
				cmds: _elm_lang$core$Native_List.Nil,
				subs: _elm_lang$core$Native_List.Nil
			};

		_elm_lang$core$Native_Scheduler.rawSend(managers[home], { ctor: 'fx', _0: fx });
	}
}

function gatherEffects(isCmd, bag, effectsDict, taggers)
{
	switch (bag.type)
	{
		case 'leaf':
			var home = bag.home;
			var effect = toEffect(isCmd, home, taggers, bag.value);
			effectsDict[home] = insert(isCmd, effect, effectsDict[home]);
			return;

		case 'node':
			var list = bag.branches;
			while (list.ctor !== '[]')
			{
				gatherEffects(isCmd, list._0, effectsDict, taggers);
				list = list._1;
			}
			return;

		case 'map':
			gatherEffects(isCmd, bag.tree, effectsDict, {
				tagger: bag.tagger,
				rest: taggers
			});
			return;
	}
}

function toEffect(isCmd, home, taggers, value)
{
	function applyTaggers(x)
	{
		var temp = taggers;
		while (temp)
		{
			x = temp.tagger(x);
			temp = temp.rest;
		}
		return x;
	}

	var map = isCmd
		? effectManagers[home].cmdMap
		: effectManagers[home].subMap;

	return A2(map, applyTaggers, value)
}

function insert(isCmd, newEffect, effects)
{
	effects = effects || {
		cmds: _elm_lang$core$Native_List.Nil,
		subs: _elm_lang$core$Native_List.Nil
	};
	if (isCmd)
	{
		effects.cmds = _elm_lang$core$Native_List.Cons(newEffect, effects.cmds);
		return effects;
	}
	effects.subs = _elm_lang$core$Native_List.Cons(newEffect, effects.subs);
	return effects;
}


// PORTS

function checkPortName(name)
{
	if (name in effectManagers)
	{
		throw new Error('There can only be one port named `' + name + '`, but your program has multiple.');
	}
}


// OUTGOING PORTS

function outgoingPort(name, converter)
{
	checkPortName(name);
	effectManagers[name] = {
		tag: 'cmd',
		cmdMap: outgoingPortMap,
		converter: converter,
		isForeign: true
	};
	return leaf(name);
}

var outgoingPortMap = F2(function cmdMap(tagger, value) {
	return value;
});

function setupOutgoingPort(name)
{
	var subs = [];
	var converter = effectManagers[name].converter;

	// CREATE MANAGER

	var init = _elm_lang$core$Native_Scheduler.succeed(null);

	function onEffects(router, cmdList, state)
	{
		while (cmdList.ctor !== '[]')
		{
			// grab a separate reference to subs in case unsubscribe is called
			var currentSubs = subs;
			var value = converter(cmdList._0);
			for (var i = 0; i < currentSubs.length; i++)
			{
				currentSubs[i](value);
			}
			cmdList = cmdList._1;
		}
		return init;
	}

	effectManagers[name].init = init;
	effectManagers[name].onEffects = F3(onEffects);

	// PUBLIC API

	function subscribe(callback)
	{
		subs.push(callback);
	}

	function unsubscribe(callback)
	{
		// copy subs into a new array in case unsubscribe is called within a
		// subscribed callback
		subs = subs.slice();
		var index = subs.indexOf(callback);
		if (index >= 0)
		{
			subs.splice(index, 1);
		}
	}

	return {
		subscribe: subscribe,
		unsubscribe: unsubscribe
	};
}


// INCOMING PORTS

function incomingPort(name, converter)
{
	checkPortName(name);
	effectManagers[name] = {
		tag: 'sub',
		subMap: incomingPortMap,
		converter: converter,
		isForeign: true
	};
	return leaf(name);
}

var incomingPortMap = F2(function subMap(tagger, finalTagger)
{
	return function(value)
	{
		return tagger(finalTagger(value));
	};
});

function setupIncomingPort(name, callback)
{
	var sentBeforeInit = [];
	var subs = _elm_lang$core$Native_List.Nil;
	var converter = effectManagers[name].converter;
	var currentOnEffects = preInitOnEffects;
	var currentSend = preInitSend;

	// CREATE MANAGER

	var init = _elm_lang$core$Native_Scheduler.succeed(null);

	function preInitOnEffects(router, subList, state)
	{
		var postInitResult = postInitOnEffects(router, subList, state);

		for(var i = 0; i < sentBeforeInit.length; i++)
		{
			postInitSend(sentBeforeInit[i]);
		}

		sentBeforeInit = null; // to release objects held in queue
		currentSend = postInitSend;
		currentOnEffects = postInitOnEffects;
		return postInitResult;
	}

	function postInitOnEffects(router, subList, state)
	{
		subs = subList;
		return init;
	}

	function onEffects(router, subList, state)
	{
		return currentOnEffects(router, subList, state);
	}

	effectManagers[name].init = init;
	effectManagers[name].onEffects = F3(onEffects);

	// PUBLIC API

	function preInitSend(value)
	{
		sentBeforeInit.push(value);
	}

	function postInitSend(value)
	{
		var temp = subs;
		while (temp.ctor !== '[]')
		{
			callback(temp._0(value));
			temp = temp._1;
		}
	}

	function send(incomingValue)
	{
		var result = A2(_elm_lang$core$Json_Decode$decodeValue, converter, incomingValue);
		if (result.ctor === 'Err')
		{
			throw new Error('Trying to send an unexpected type of value through port `' + name + '`:\n' + result._0);
		}

		currentSend(result._0);
	}

	return { send: send };
}

return {
	// routers
	sendToApp: F2(sendToApp),
	sendToSelf: F2(sendToSelf),

	// global setup
	effectManagers: effectManagers,
	outgoingPort: outgoingPort,
	incomingPort: incomingPort,

	htmlToProgram: htmlToProgram,
	program: program,
	programWithFlags: programWithFlags,
	initialize: initialize,

	// effect bags
	leaf: leaf,
	batch: batch,
	map: F2(map)
};

}();