Station/Server Installation

local STATION_URL = "2CwStA8E"
local SERVER_URL = "giJN22xf"

--Writes text at a specific position.
function writeC(text, tc)
    term.setTextColor(tc)
    print(text)
end

--Trims a string.
function trim(s)
    return (s:gsub("^%s*(.-)%s*$", "%1"))
end

--Loops until a choice is made.
function getInput()
    local answer
    while (true) do
        writeC("Is this computer a station or server?", colors.lightBlue)
        term.setTextColor(colors.white)
        answer = trim(string.lower(read()))
        if (answer == "station" or answer == "server") then
            return answer
        end
    end
end

writeC("Welcome to HandieAndy's Railcraft Station installation.", colors.blue)
local answer = getInput()
if (answer == "station") then
    writeC("Installing station program.", colors.yellow)
    local x, y = term.getCursorPos()
    term.setCursorPos(1,y+1)
    term.setTextColor(colors.lightGray)
    shell.run("pastebin", "get", STATION_URL, "station")
    local x, y = term.getCursorPos()
    term.setCursorPos(1, y+1)
    writeC("Got program, creating startup script.", colors.yellow)
    local f = fs.open("startup", "w")
    f.write('shell.run("station")')
    f.close()
    writeC("Startup script done.", colors.blue)
    writeC("Starting config generation.", colors.yellow)
    local config = {tracks = {}}
    writeC("What is the ID of the server that will be controlling this station?", colors.lightBlue)
    term.setTextColor(colors.white)
    config.server_id = tonumber(read())
    writeC("What is the unique destination name of this station?", colors.lightBlue)
    term.setTextColor(colors.white)
    config.dest = read()
    writeC("What is the cosmetic name?", colors.lightBlue)
    term.setTextColor(colors.white)
    config.name = read()
    writeC("Enter monitor ID: (Example: 'monitor_0')", colors.lightBlue)
    term.setTextColor(colors.white)
    config.monitor_id = read()
    writeC("Enter noteblock ID: (Example: 'note_block_0')", colors.lightBlue)
    term.setTextColor(colors.white)
    config.note_block_id = read()
    writeC("How many tracks does this station have?", colors.lightBlue)
    term.setTextColor(colors.white)
    local trackCount = tonumber(read())
    for i=1,trackCount do
        config.tracks[i] = {train = -1,}
        writeC("Enter track "..i.."'s sensor ID: ", colors.lightBlue)
        term.setTextColor(colors.white)
        config.tracks[i].sensor_id = read()
        writeC("Enter track "..i.."'s detector decimal color code. For more info, see www.computercraft.info/wiki/Colors_(API).", colors.lightBlue)
        term.setTextColor(colors.white)
        config.tracks[i].detectorColor = tonumber(read())
        writeC("Enter track "..i.."'s ticket retriever color code.", colors.lightBlue)
        term.setTextColor(colors.white)
        config.tracks[i].ticketColor = tonumber(read())
    end
    local f = fs.open("station_config", "w")
    f.write(textutils.serialize(config))
    f.close()
    writeC("Setup is now complete. Remember to double check that everything has been set up properly, and if so, this station is ready for operation after a restart. You may also restart the server for optimal performance.", colors.lime)
elseif (answer == "server") then
    writeC("Installing server program.", colors.yellow)
    local x, y = term.getCursorPos()
    term.setCursorPos(1,y+1)
    term.setTextColor(colors.lightGray)
    shell.run("pastebin", "get", SERVER_URL, "server")
    local x, y = term.getCursorPos()
    term.setCursorPos(1, y+1)
    writeC("Got program, creating startup script.", colors.yellow)
    local f = fs.open("startup", "w")
    f.write('shell.run("server")')
    f.close()
    writeC("Startup script done.", colors.blue)
    writeC("Server installed successfully. Place a wireless modem on top of this computer, and restart it.", colors.lime)
end