Solution To Reddit Daily Programmer #255 - Playing With Light

change-lightswitch.ps1

#https://www.reddit.com/r/dailyprogrammer/comments/46zm8m/20160222_challenge_255_easy_playing_with_light/

#Function for flipping the switches.
function FlipSwitch ($Array,$Position)
{
    $currentBoolean = $Array[$Position]
    if($currentBoolean)
    {
        $newValue = $false
    }
    else
    {
        $newValue = $true
    }
    
    return $newValue
}

#First get input for the total number of lightswitches.
Write-Output "How many lightswitches are there?"
$numberOfSwitches = Read-Host "Enter a number"

#Create the array.
$lightSwitches = @()

#Set the initial values to all be off.
for($i = 0; $i -lt $numberOfSwitches; $i++)
{
    $lightSwitches += $false
}

#Loop through the input for calculating the lights.
$gettingInput = $true

while($gettingInput)
{
    $isValid = $true
    do
    {
        Write-Output "Enter the range, separated by a space. Enter 'n' to quit!"
        $currentRange = Read-Host "Enter two numbers"
        
        if($currentRange.ToLower() -eq "n")
        {
            $gettingInput = $false
        }
        else
        {
            $numberArray = $currentRange.Split(" ")
            if($numberArray.Count -eq 2)
            {
                #We have two numbers, make sure they're legit.
                $firstNumber = [int]$numberArray[0]
                $secondNumber = [int]$numberArray[1]
                
                #Change the values if we need the criteria.
                if(($firstNumber -ge 0) -and ($firstNumber -lt $numberOfSwitches) -and ($secondNumber -ge 0) -and ($secondNumber -lt $numberOfSwitches))
                {
                    if($firstNumber -le $secondNumber)
                    {
                        for($i = $firstNumber; $i -le $secondNumber; $i++)
                        {

                            $lightSwitches[$i] = FlipSwitch -Array $lightSwitches -Position $i
                        }
                    }
                    else
                    {
                        for($i = $firstNumber; $i -ge $secondNumber; $i--)
                        {
                            $lightSwitches[$i] = FlipSwitch -Array $lightSwitches -Position $i
                        }
                    }
                    $isValid = $true
                }
                else
                {
                    Write-Host "The values were not valid!" -ForegroundColor Red 
                    $isValid = $false
                }
            }
            else
            {
                Write-Host "That input is invalid!" -ForegroundColor Red
                $isValid = $false
            }
        }
    } while(-not $isValid)   
}

#Write the final output.
foreach($switch in $lightSwitches)
{
    if($switch)
    {
        Write-Host "X" -NoNewline
    }
    else
    {
        Write-Host "." -NoNewline
    }
}
Write-Host ""