touch monitor lock

-- svennp is awesome!

--variables

for k,v in pairs(rs.getSides()) do
    if peripheral.getType(v) == "monitor" then
        mon = peripheral.wrap(v)
        break
    end
end
side = "front"
unterminatable = false
timeout = 3
input = ""
if fs.exists(".pass") then
    f = fs.open(".pass","r")
    pass = f.readLine()
    f.close()
else write("input new code (4 digits): ")
    pass = read("*")
    if tonumber(pass) and #pass == 4 then
        f = fs.open(".pass","w")
        f.writeLine(pass)
        f.close()
    else error("please use numbers only!  (4 digits!)")
    end
end

--functions

function resetcolor()
    mon.setTextColor(colors.white)
    mon.setBackgroundColor(colors.black)
end

function numcolor(num)
    mon.setTextColor(colors.blue)
    mon.setBackgroundColor(colors.black)
    mon.write(num)
end

function linecolor(line)
    mon.setTextColor(colors.brown)
    mon.setBackgroundColor(colors.brown)
    mon.write(line)
end

function getnum()
    e,p1,p2,p3 = os.pullEvent("monitor_touch")
    if p3 == 2 then
        if p2 == 2 then
            return 1
        elseif p2 == 4 then
            return 2
        elseif p2 == 6 then
            return 3
        end
    elseif p3 == 3 then
        if p2 == 2 then
            return 4
        elseif p2 == 4 then
            return 5
        elseif p2 == 6 then
            return 6
        end
    elseif p3 == 4 then
        if p2 == 2 then
            return 7
        elseif p2 == 4 then
            return 8
        elseif p2 == 6 then
            return 9
        end
    elseif p3 == 5 then
        if p2 == 1 or p2 == 2 or p2 == 3 then
            return "cancel"
        elseif p2 == 5 or p2 == 6 or p2 == 7 then
            return "ok"
        end
    else return getnum()
    end
end

function printinterface()
    mon.setCursorPos(1,1)
    resetcolor()
    mon.write(">      ")
    mon.setCursorPos(1,2)
    linecolor("|") numcolor("1") linecolor("|") numcolor("2") linecolor("|") numcolor("3") linecolor("|")
    mon.setCursorPos(1,3)
    linecolor("|") numcolor("4") linecolor("|") numcolor("5") linecolor("|") numcolor("6") linecolor("|")
    mon.setCursorPos(1,4)
    linecolor("|") numcolor("7") linecolor("|") numcolor("8") linecolor("|") numcolor("9") linecolor("|")
    mon.setCursorPos(1,5)
    mon.setBackgroundColor(colors.red) mon.write("   ") mon.setBackgroundColor(colors.black) mon.write(" ") mon.setBackgroundColor(colors.green) mon.write("   ")
end

function printcorrect()
    mon.setBackgroundColor(colors.green)
    mon.setTextColor(colors.green)
    for i = 1,5 do
        mon.setCursorPos(1,i)
        mon.write("       ")
    end
    resetcolor()
end

function printwrong()
    mon.setBackgroundColor(colors.red)
    mon.setTextColor(colors.red)
    for i = 1,5 do
        mon.setCursorPos(1,i)
        mon.write("       ")
    end
    resetcolor()
end

-- other stuff

term.clear()
term.setCursorPos(1,1)
print("running svennp's lock program")

if unterminatable then
    print("termination of program not possible!")
else
    print("termination of program possible!")
end

if unterminatable then
    os.pullEvent = os.oullEventRaw
end

--main loop

printinterface()
while true do
    mon.setCursorPos(1,1)
    resetcolor()
    mon.write(">      ")
    mon.setCursorPos(3,1)

    for i = 1,#input do
        mon.write("*")
    end

    q = nil
    while q == nil do
        q = getnum()
    end

    if type(q) == "string" then
        if q == "cancel" then
            input = ""
        elseif q == "ok" then
            if input == pass then
                printcorrect()
                rs.setOutput(side,true)
                sleep(timeout)
                rs.setOutput(side,false)
            else
                printwrong()
                sleep(timeout)
            end
            input = ""
            printinterface()
        end
    elseif type(q) == "number" then
        if #input < 4 then
            input = input..tostring(q)
        end
    end
end