package com.example.myapplication

fun main() {
    val startingNode = Node(0,0)
    val stringInput = readLine()!!
    if (stringInput.isEmpty()){
        return
    }
    val node = getGridSizeFromInput(stringInput)
    if(node==null){
        println("You entered wrong format of grid size")
    }else{
        val listOfCoordinates = parseInput(node,stringInput)
        val commands = ArrayList<String>()
        for (node in listOfCoordinates){
            commands.addAll(travel(startingNode, node))
            startingNode.x=node.x
            startingNode.y=node.y
        }
        println(convertCommandsToString(commands))
    }
}

fun getGridSizeFromInput(stringInput: String): Node?{
    val inputParsed = stringInput.split(" ")[0].split("x")
    return if(inputParsed.size==2){
        try {
            Node(inputParsed[0].toInt(),inputParsed[1].toInt())
        }catch (e: NumberFormatException){
            null
        }
    }else{
        null
    }
}

fun parseInput(node: Node, stringInput: String): ArrayList<Node>{
    val coordList = ArrayList<Node>()
    var input = stringInput
    val inputParsed = stringInput.split(" ")
    input = input.replace(inputParsed[0],"")
    input = input.replace(" ","")
    val parsedCoords = input.split(")(")
    for (i in parsedCoords){
        val iString = i.replace("(","").replace(")","")
        val coords = iString.split(",")
        if(coords[0].isNotEmpty() && coords[1].isNotEmpty()){
            try {
                if(coords[0].toInt()<node.x && coords[1].toInt()<node.y){
                    coordList.add(Node(coords[0].toInt(), coords[1].toInt()))
                }
            }catch (e: NumberFormatException){
                println(e)
            }
        }
    }
    return coordList
}

fun travel(startNode: Node, endNode: Node): ArrayList<String>{
    val commands = ArrayList<String>()
    var startX = startNode.x
    var startY = startNode.y
    val endX = endNode.x
    val endY = endNode.y
        if(startX>endX){
            commands.add("W".repeat(startX-endX))
            startX=endX
        }else if(startX<endX){
            commands.add("E".repeat(endX-startX))
            startX=endX
        }
        if(startY>endY){
            commands.add("S".repeat(startY-endY))
            startY=endY
        }else if(startY<endY){
            commands.add("N".repeat(endY-startY))
            startY=endY
        }
        if(startX==endX && startY==endY){
            commands.add("D")
        }
    return commands
}

fun convertCommandsToString(commands: ArrayList<String>):String{
    var convertedCommands = ""
    for (command in commands){
        convertedCommands += command
    }
    return convertedCommands
}