local function findPeripheral( kind )
    for _,v in pairs( rs.getSides ) do
        if peripheral.getType( v ) == kind then
            return v
        end
    end

    return nil
end

local monitor  -- empty variable waiting for peripheral.wrap
local monitorSide = findPeripheral( "monitor" )
local sizeX, sizeY = term.getSize() -- get the pixel size of the screen ( currently the computers screen )

if not monitorSide then
    print( "No monitor found! :(")
    error() -- exit the program here
else
    monitor = peripheral.wrap( monitorSide )
end


local msg = "Monitor has focus"
term.setCursorPos( sizeX / 2 - #msg / 2, sizeY / 2 ) -- set the cursor so when we print the message it will be in the middle
print( msg )

-- only add the DIFFERENCES between them all, that way if there are 2 trains and they are ( for example ) at purple AND red, the red chars will not override the purple chars
local activeLines = {
    topAtStation = "*",
    topBetweenStation = "++++",
    -- add other ones here, again ONLY the differences!
}

local function drawScreen()
    term.clear()
    term.setCursorPos( 1,1 )

    -- first we draw the default path on the screen



    -- now we draw on the train progress
    local rsInput = rs.getBundledInput("back")

    if colors.test( rsInput, colors.purple ) then
        term.setCursorPos( 1,1 )
        write( activeLines.topAtStation )
    end

    if colors.test( rsInput, colors.red ) then
        term.setCursorPos( 2, 1 )
        write( activeLines.topBetweenStation )
    end

    if colors.test( rsInput, colors.orange ) then
        term.setCursorPos( 6, 1 )
        write( activeLines.topAtStation )
    end

    if colors.text( rsInput, colors.white ) then
        term.setCursorPos( 7, 1 )
        write( activeLines.topBetweenStation )
    end

    -- etc, etc, etc
end

term.redirect( monitor ) -- give control of term functions to the monitor object

local refresh = os.startTimer( 1 ) -- this starts a timer that takes 1 second for refreshing ( its better than sleep with event loops )

while true do
    drawScreen() -- call the function that will draw the screen

    os.pullEvent( "timer" ) -- change this to os.pullEventRaw later to stop program termination ... the program will wait here until the timer finishes

    refresh = os.startTimer( 1 ) -- restart the timer
end

term.restore() -- give control back to the computers screen