startup

loginTable = {
    {username="the cat", pw="password"},
    {username="example", pw="example"},
}
letters = {"A", "a", "B", "b", "C", "c", "D", "d", "E", "e", "F", "f", "G", "g", "H", "h", "I", "i", " ", "J", "j", "K", "k", "L", "l", "M", "m", "N", "n", "O", "o", "P", "p", "Q", "q", "R", "r", "S", "s", "T", "t", "U", "u", "V", "v", "W", "w", "X", "x", "Y", "y", "Z", "z", "_"}
usernameLetters = {}

function breakString() -- This Breaks up the string the userenters so it can be compard induvidually
    for i = 1, username:len() do
        table.insert(usernameLetters, username:sub(i, i))
    end
end

function welcome() -- This compares the strings from letters with the username that was entered by the user
    breakString()
    term.clear()
    term.setCursorPos(1, 1)
    write("Welcome:")
    for userNum = 1, #username do
        for i = 1, #letters do
            term.setCursorPos(9+userNum, 1)
            if letters[i] == usernameLetters[userNum] then
                write(letters[i])
                break
            else
                write(letters[i])
            end
            os.sleep(0.001)
        end
    end
end

function printLine(bgColour, fgColour, x, y, length, text) -- This is used to print the text with the coloured box to the right of it example: printLine(colors.green, colors.red, 10, 4, 12, "Username:")
    term.setBackgroundColour(colors.black)
    term.setTextColour(fgColour)
    term.setCursorPos(x, y)
    for i = 0, length do
        term.setBackgroundColour(bgColour)
        write(" ")
    end
    term.setBackgroundColour(colors.black)
    term.setCursorPos(x-#text, y)
    write(text)
end

function readInput(bgColour, fgColour, x, y, inRead) -- This is simply a read() but with background and forground color
    term.setBackgroundColour(bgColour)
    term.setTextColour(fgColour)
    term.setCursorPos(x, y)
    local input = read(inRead)
    term.setBackgroundColour(colors.black)
    return input
end

function login()
    repeat
        isCorrect = false
        term.clear()
        term.setBackgroundColour(colors.black)
        term.setCursorPos(1,1)

        printLine(colors.green, colors.red, usernameX, usernameY, 14, "Username:")
        printLine(colors.green, colors.red, passwordX, passwordY, 14, "Password:")
        username = readInput(colors.green, colors.red, usernameX, usernameY)
        password = readInput(colors.green, colors.red, passwordX, passwordY, "*")
        for i = 1, #loginTable do
            if loginTable[i].username == username and loginTable[i].pw == password then
                isCorrect = true
            end
        end
    until isCorrect
end

function loading()
    --Enter here for loading feel free to change what its currently doing
    for i = 0, 100 do
        term.clear()
        term.setCursorPos(1,1)
        print("Loading: "..i.."%")
        os.sleep(.1)
    end
end

-- [[ Change these values to change the pos of the login screen (mess around with the values to see what happens) ]]
usernameX = 20
usernameY = 5
passwordX = 20
passwordY = 7
term.clear()

login() -- calling login method
loading() --if you want loading so after the login you can write loading: 20% going up so on then when it ends it will do the welcome scrolling text
welcome() -- welcomes the user (scrolls through text)


term.setCursorPos(1,10)