module.exports = function(RED) {
    function BooleanLogicUltimate(config) {
		RED.nodes.createNode(this, config);
		var node = this;
		node.config = config;
		node.jSonStates = {}; // JSON object with elements. It's not an array! Format: {"Rain":true,"Dusk":true,"MotionSensor":true}
		node.sInitializeWith = typeof node.config.sInitializeWith === "undefined" ? "WaitForPayload" : node.config.sInitializeWith;
		var fs = require('fs');
		var decimal = /^\s*[+-]{0,1}\s*([\d]+(\.[\d]*)*)\s*$/
	
		// Helper for the config html, to be able to delete the peristent states file
		RED.httpAdmin.get("/stateoperation_delete", RED.auth.needsPermission('BooleanLogicUltimate.read'), function (req, res) {
			//node.send({ req: req });
			// Detele the persist file
			//var _node = RED.nodes.getNode(req.query.nodeid); // Gets node object from nodeit, because when called from the config html, the node object is not defined
			var _nodeid = req.query.nodeid;
			try {
				if (fs.existsSync("states/" + _nodeid.toString())) fs.unlinkSync("states/" + _nodeid.toString());
			} catch (error) {
			}
			res.json({ status: 220 });
		});

		// Populate the state array with the persisten file
		if (node.config.persist == true) {
			try {
				var contents = fs.readFileSync("states/" + node.id.toString()).toString();
				if (typeof contents !== 'undefined') {
					node.jSonStates = JSON.parse(contents);
					setNodeStatus({fill: "blue",shape: "ring",text: "Loaded persistent states (" + Object.keys(node.jSonStates).length + " total)."});
				}
			} catch (error) {
				setNodeStatus({fill: "grey",shape: "ring",text: "No persistent states"});
			}
			
		} else {
			setNodeStatus({fill: "yellow",shape: "dot",text: "Waiting for input states"});
		}


		// 14/08/2019 If some inputs are to be initialized, create a dummy items in the array
		initUndefinedInputs();
		

		this.on('input', function (msg) {
			
			var topic = msg.topic;
			var payload = msg.payload;
			
			if (topic !== undefined && payload !== undefined) {
				var value = ToBoolean( payload );
			
				// 14/08/2019 if inputs are initialized, remove a "dummy" item from the state's array, as soon as new topic arrives
				if(node.sInitializeWith !== "WaitForPayload")
				{
					// Search if the current topic is in the state array
					if (typeof node.jSonStates[topic] === "undefined")
					{
						// Delete one dummy 
						for (let index = 0; index < node.config.inputCount; index++) {
							if (node.jSonStates.hasOwnProperty("dummy" + index)) {
								//RED.log.info(JSON.stringify(node.jSonStates))
								delete node.jSonStates["dummy" + index];
								//RED.log.info(JSON.stringify(node.jSonStates))
								break;
							} 
						}
					}
				}
			
				// Add current attribute
				node.jSonStates[topic] = value;
				
				// Save the state array to a perisistent file
				if (node.config.persist == true) { 
					try {
						if (!fs.existsSync("states")) fs.mkdirSync("states");
						fs.writeFileSync("states/" + node.id.toString(),JSON.stringify(node.jSonStates));
	
					} catch (error) {
						setNodeStatus({fill: "red",shape: "dot",text: "Node cannot write to filesystem: " + error});
					}
				}
								
				// Do we have as many inputs as we expect?
				var keyCount = Object.keys(node.jSonStates).length;

				if( keyCount == node.config.inputCount ) {
					
					var resAND = CalculateResult("AND");
					var resOR = CalculateResult("OR");
					var resXOR = CalculateResult("XOR");

					if (node.config.filtertrue == "onlytrue") {
						if (!resAND) { resAND = null };
						if (!resOR) { resOR = null };
						if (!resXOR) { resXOR = null };
					}

					// Operation mode evaluation
					if (node.config.outputtriggeredby == "onlyonetopic") {
						if (typeof node.config.triggertopic !== "undefined"
							&& node.config.triggertopic !== ""
							&& msg.hasOwnProperty("topic") && msg.topic !==""
							&& node.config.triggertopic === msg.topic)
						{
							SetResult(resAND, resOR, resXOR, node.config.topic);
						} else
						{
							setNodeStatus({ fill: "grey", shape: "ring", text: "Saved (" + (msg.hasOwnProperty("topic") ? msg.topic : "empty input topic") + ") " + value});
						}
					} else
					{
						SetResult(resAND, resOR, resXOR, node.config.topic);
					}
				}
				else if(keyCount > node.config.inputCount ) {
					setNodeStatus({ fill: "gray", shape: "ring", text: "Reset due to unexpected new topic"});
					DeletePersistFile();
				} else {
					setNodeStatus({ fill: "green", shape: "ring", text: "Arrived topic " + keyCount + " of " + node.config.inputCount});
				}
			}
		});
		
		this.on('close', function(removed, done) {
			if (removed) {
				// This node has been deleted
				// Delete persistent states on change/deploy
				DeletePersistFile();
			} else {
				// This node is being restarted
			}
			done();
		});

		function DeletePersistFile (){
			// Detele the persist file
			try {
				if (fs.existsSync("states/" + node.id.toString())) fs.unlinkSync("states/" + node.id.toString());
				setNodeStatus({fill: "red",shape: "ring",text: "Persistent states deleted ("+node.id.toString()+")."});
			} catch (error) {
				setNodeStatus({fill: "red",shape: "ring",text: "Error deleting persistent file: " + error.toString()});
			}
			node.jSonStates = {}; // Resets inputs
			// 14/08/2019 If the inputs are to be initialized, create a dummy items in the array
			initUndefinedInputs();
		}

		function initUndefinedInputs() {
			if (node.sInitializeWith !== "WaitForPayload")
			{
				var nTotalDummyToCreate = Number(node.config.inputCount) - Object.keys(node.jSonStates).length;
				if (nTotalDummyToCreate > 0) {
					RED.log.info("BooleanLogicUltimate: Will create " + nTotalDummyToCreate + " dummy (" + node.sInitializeWith + ") values")
					for (let index = 0; index < nTotalDummyToCreate; index++) {
						node.jSonStates["dummy" + index] = node.sInitializeWith === "false" ? false : true;
					}
					setTimeout(() => { setNodeStatus({fill: "green",shape: "ring",text: "Initialized " + nTotalDummyToCreate + " undefined inputs with " + node.sInitializeWith});}, 4000)
				} 
			}
		}

		function setNodeStatus({fill, shape, text})
		{
			var dDate = new Date();
			node.status({fill: fill,shape: shape,text: text + " (" + dDate.getDate() + ", " + dDate.toLocaleTimeString() + ")"})
		}

		function CalculateResult(_operation) {
			var res;
			
			if( _operation == "XOR") {
				res = PerformXOR();
			}
			else {
				// We need a starting value to perform AND and OR operations.				
				var keys = Object.keys(node.jSonStates);
				res = node.jSonStates[keys[0]];
				
				for( var i = 1; i < keys.length; ++i ) {
					var key = keys[i];
					res = PerformSimpleOperation( _operation, res, node.jSonStates[key] );
				}
			}
			
			return res;			
		}		
		
		function PerformXOR()
		{
			// XOR = exclusively one input is true. As such, we just count the number of true values and compare to 1.
			var trueCount = 0;
			
			for( var key in node.jSonStates ) {
				if( node.jSonStates[key] ) {
					trueCount++;
				}
			}
			
			return trueCount == 1;
		}
		
		function PerformSimpleOperation( operation, val1, val2 ) {
			var res;
			
			if( operation === "AND" ) {
				res = val1 && val2;
			}
			else if( operation === "OR" ) {
				res = val1 || val2;
			}
			else {
				node.error( "Unknown operation: " + operation );
			}
			
			return res;
		}
		
		function ToBoolean( value ) {
			var res = false;
	
			if (typeof value === 'boolean') {
				res = value;
			} 
			else if( typeof value === 'number' || typeof value === 'string' ) {
				// Is it formated as a decimal number?
				if( decimal.test( value ) ) {
					var v = parseFloat( value );
					res = v != 0;
				}
				else {
					res = value.toLowerCase() === "true";
				}
			}
			
			return res;
		};
		
		function SetResult(_valueAND, _valueOR, _valueXOR, optionalTopic) {
			setNodeStatus({fill: "green",shape: "dot",text: "(AND)" + _valueAND + " (OR)" +_valueOR + " (XOR)" +_valueXOR});
			
			if (_valueAND!=null){
				var msgAND = { 
					topic: optionalTopic === undefined ? "result" : optionalTopic,
					operation:"AND",
					payload: _valueAND
				};
			}
			if (_valueOR!=null){
				var msgOR = { 
					topic: optionalTopic === undefined ? "result" : optionalTopic,
					operation:"OR",
					payload: _valueOR
				};
			}
			if (_valueXOR!=null){
				var msgXOR = { 
					topic: optionalTopic === undefined ? "result" : optionalTopic,
					operation:"XOR",
					payload: _valueXOR
				};
			}
			node.send([msgAND,msgOR,msgXOR]);
		};
    }	
	
    RED.nodes.registerType("BooleanLogicUltimate",BooleanLogicUltimate);
}