Change Wallpaper in order

$source_path="C:\USB"   #Change the path of source image file folder
$dest_path="D:\Wallpaper"   #Change the path to shared folder where client can update wallpaper
$filename_fix="background.png"   # File name defaut in GPO 

# Save pictures to the correct directory

if( -Not (Test-Path -Path $dest_path ) )
{
    New-Item -ItemType directory -Path $dest_path
    Copy-Item "$source_path\photo1.png*" -Destination $dest_path

}

elseif (test-path "$dest_path\photo1.png*")
{
    Remove-Item "$dest_path\*"
    Copy-Item "$source_path\photo2.png*" -Destination $dest_path

}

elseif (test-path "$dest_path\photo2.png*")
{
    Remove-Item "$dest_path\*"
    Copy-Item "$source_path\photo3.png*" -Destination $dest_path

}


#return to photo1
elseif (test-path "$dest_path\photo3.png*")
{
    Remove-Item "$dest_path\*"
    Copy-Item "$source_path\photo1.png*" -Destination $dest_path

}
##### DO NOT EDIT CODE BELOW #######
##### Copy file to Folder GPO ######
$Path_of_file = (get-childitem $dest_path -recurse).FullName
Copy-Item $Path_of_file -Destination "$dest_path\$filename_fix"