Title

-- Get the terminal size. Helpful for displaying text
local w, h = term.getSize()

-- Load in Anavrins sha api
local sha = require "/apis/sha"

-- Set up the page that we're currently on
local page = "title"

-- This function will be used to draw the title page when the page is set to title
local function drawTitle()
    -- Paint the background black
    paintutils.drawFilledBox(0, 0, w, h, colors.black)

    -- Set up the cursor position to write the "Diamond" text
    term.setCursorPos(0,3)
    x, y = term.getCursorPos()
    x = math.max(math.floor((w / 2) - (40 / 2)), 0)
    term.setCursorPos(x,y)

    -- Diamond Text
    -- D
    paintutils.drawLine(x, y, x, y + 4, colors.cyan)
    paintutils.drawLine(x + 1, y, x + 3, y, colors.cyan)
    paintutils.drawLine(x + 1, y + 4, x + 3, y + 4, colors.cyan)
    paintutils.drawLine(x + 4, y + 1, x + 4, y + 3, colors.cyan)
    -- I
    paintutils.drawLine(x + 6, y, x + 10, y, colors.cyan)
    paintutils.drawLine(x + 6, y + 4, x + 10, y + 4, colors.cyan)
    paintutils.drawLine(x + 8, y + 1, x + 8, y + 3, colors.cyan)
    -- A
    paintutils.drawLine(x + 13, y, x + 15, y, colors.cyan)
    paintutils.drawLine(x + 12, y + 1, x + 12, y + 4, colors.cyan)
    paintutils.drawLine(x + 16, y + 1, x + 16, y + 4, colors.cyan)
    paintutils.drawLine(x + 13, y + 2, x + 15, y + 2, colors.cyan)
    -- M
    paintutils.drawLine(x + 18, y, x + 18, y + 4, colors.cyan)
    paintutils.drawLine(x + 22, y, x + 22, y + 4, colors.cyan)
    paintutils.drawPixel(x + 19, y + 1, colors.cyan)
    paintutils.drawPixel(x + 20, y + 2, colors.cyan)
    paintutils.drawPixel(x + 21, y + 1, colors.cyan)
    -- O
    paintutils.drawBox(x + 24, y, x + 28, y + 4, colors.cyan)
    -- N
    paintutils.drawLine(x + 30, y, x + 30, y + 4, colors.cyan)
    paintutils.drawLine(x + 34, y, x + 34, y + 4, colors.cyan)
    paintutils.drawPixel(x + 31, y + 1, colors.cyan)
    paintutils.drawPixel(x + 32, y + 2, colors.cyan)
    paintutils.drawPixel(x + 33, y + 3, colors.cyan)
    -- D
    paintutils.drawLine(x + 36, y, x + 36, y + 4, colors.cyan)
    paintutils.drawLine(x + 37, y, x + 39, y, colors.cyan)
    paintutils.drawLine(x + 37, y + 4, x + 39, y + 4, colors.cyan)
    paintutils.drawLine(x + 40, y + 1, x + 40, y + 3, colors.cyan)

    -- Digger text

    y = y + 6
    x = math.max(math.floor((w / 2) - (35 / 2)), 0)

    -- D
    paintutils.drawLine(x, y, x, y + 4, colors.cyan)
    paintutils.drawLine(x + 1, y, x + 3, y, colors.cyan)
    paintutils.drawLine(x + 1, y + 4, x + 3, y + 4, colors.cyan)
    paintutils.drawLine(x + 4, y + 1, x + 4, y + 3, colors.cyan)
    -- I
    paintutils.drawLine(x + 6, y, x + 10, y, colors.cyan)
    paintutils.drawLine(x + 6, y + 4, x + 10, y + 4, colors.cyan)
    paintutils.drawLine(x + 8, y + 1, x + 8, y + 3, colors.cyan)
    -- G
    paintutils.drawLine(x + 12, y, x + 12, y + 4, colors.cyan)
    paintutils.drawLine(x + 13, y, x + 17, y, colors.cyan)
    paintutils.drawLine(x + 13, y + 4, x + 17, y + 4, colors.cyan)
    paintutils.drawLine(x + 14, y + 2, x + 16, y + 2, colors.cyan)
    paintutils.drawPixel(x + 17, y + 3, colors.cyan)
    -- G
    paintutils.drawLine(x + 19, y, x + 19, y + 4, colors.cyan)
    paintutils.drawLine(x + 20, y, x + 24, y, colors.cyan)
    paintutils.drawLine(x + 19, y + 4, x + 24, y + 4, colors.cyan)
    paintutils.drawLine(x + 21, y + 2, x + 23, y + 2, colors.cyan)
    paintutils.drawPixel(x + 24, y + 3, colors.cyan)
    -- E
    paintutils.drawLine(x + 26, y, x + 26, y + 4, colors.cyan)
    paintutils.drawLine(x + 27, y, x + 30, y, colors.cyan)
    paintutils.drawLine(x + 27, y + 4, x + 30, y + 4, colors.cyan)
    paintutils.drawLine(x + 27, y + 2, x + 28, y + 2, colors.cyan)
    -- R
    paintutils.drawLine(x + 32, y, x + 32, y + 4, colors.cyan)
    paintutils.drawLine(x + 33, y, x + 35, y, colors.cyan)
    paintutils.drawLine(x + 33, y + 3, x + 35, y + 3, colors.cyan)
    paintutils.drawLine(x + 36, y + 1, x + 36, y + 2, colors.cyan)
    paintutils.drawPixel(x + 36, y + 4, colors.cyan)

    term.setTextColour(colours.white)
    term.setBackgroundColor(colors.cyan)

    -- New Game button

    y = y + 7
    x = math.max(math.floor((w / 2) - (12)), 0)

    term.setCursorPos(x, y)
    term.write("          ")
    term.setCursorPos(x, y + 1)
    term.write(" New Game ")
    term.setCursorPos(x, y + 2)
    term.write("          ")

    -- Load Game button

    x = math.max(math.floor((w / 2) + (2)), 0)

    term.setCursorPos(x, y)
    term.write("           ")
    term.setCursorPos(x, y + 1)
    term.write(" Load Game ")
    term.setCursorPos(x, y + 2)
    term.write("           ")

    -- Leaderboard button

    x = math.max(math.floor((w) - (5)), 0)

    paintutils.drawPixel(x, y + 2, colors.brown)
    paintutils.drawLine(x + 1, y, x + 1, y + 2, colors.orange)
    paintutils.drawLine(x + 2, y + 1, x + 2, y + 2, colors.lightGray)

end

-- Use this function to correctly display a number.
-- num is the number to format, if isInt is true, it will round to the nearest int
local function displayNumber(num, isInt)

    local num = num or 0
    local isInt = isInt or false
    local newNum = 0

    if num >= 1000000 then
        newNum = num / 1000000
        newNum = math.floor(newNum * 100)/100
        newNum = tostring(newNum)
        if isInt == false then
            newNum = string.format("%.1f", newNum) .. "M"
        end
    elseif num >= 1000 then
        newNum = num / 1000
        newNum = math.floor(newNum * 100)/100
        newNum = tostring(newNum)
        if isInt == false then
            newNum = string.format("%.1f", newNum) .. "K"
        end
    else
        newNum = tostring(num)
        if isInt == false then
            newNum = string.format("%.1f", newNum)
        end
    end

    return newNum
end

-- This function draws the page for the new game page
local function drawNewGame()

    paintutils.drawFilledBox(0, 0, w, h, colors.black)
    term.setTextColour(colours.white)
    term.setBackgroundColor(colors.cyan)

    term.setCursorPos(1, 1)
    term.write("      ")
    term.setCursorPos(1, 2)
    term.write(" Back ")
    term.setCursorPos(1, 3)
    term.write("      ")

    term.setBackgroundColor(colors.black)
    term.setCursorPos(21, 7)
    term.write("New Game")

    term.setCursorPos(0,8)
    local x, y = term.getCursorPos()
    x = math.max(math.floor((w / 2) - (15)), 0)
    term.setCursorPos(x,y)
    term.write("(Please type in the computer)")

    term.setCursorPos(15, 10)
    term.write("Username: ")
    local username = read()

    term.setCursorPos(15, 12)
    term.write("Password: ")
    local password = read("*")

    -- This function will add the user to the system
    function save()
        -- If the user file exists, let the user know and run the save function again
        if fs.exists("users/" .. username .. "_save") then
            term.setCursorPos(13, 15)
            term.clearLine()
            term.write("That user already exists!")

            term.setCursorPos(15, 10)
            term.clearLine()

            term.setCursorPos(15, 12)
            term.clearLine()

            term.setCursorPos(15, 10)
            term.write("Username: ")
            local username = read()

            term.setCursorPos(15, 12)
            term.write("Password: ")
            local password = read("*")

            save()
        else

            -- Add in a unique salt for password hashing (Thanks PG231)
            local salt = sha.digest("i7gBq4p7p+uOCuuWvrlPgg|" .. os.epoch("utc") .. "|" .. math.random(0, 2^31 - 2)):toHex()

            -- Use the sha api to generate a hash to save for password protection
            password = sha.pbkdf2(password, salt, 16):toHex()

            -- Save the users hashed password and salt to their save file
            local hWrite = fs.open("users/" .. username .. "_save", "w")
            hWrite.writeLine(password)
            hWrite.writeLine(salt)
            hWrite.close()

            -- If there is a users file already, add this user to the list
            if fs.exists("users/" .. "users") then
                local userRead = fs.open("users/" .. "users", "r")

                local lines = {}
                while true do
                    local line = userRead.readLine()

                    if not line then break end

                    lines[#lines + 1] = line
                end

                userRead.close()

                local userWrite = fs.open("users/" .. "users", "w")
                for i, name in pairs(lines) do
                  userWrite.writeLine(name)
                end
                userWrite.writeLine(username)

                userWrite.close()

            else
                -- If this is the first user, create the users file
                local userWrite = fs.open("users/" .. "users", "w")
                userWrite.writeLine(username)
                userWrite.close()
            end

            term.setCursorPos(12, 15)
            term.clearLine()
            term.write("User was created succesfully")

            sleep(3)

            -- Redirect the page to the game page and send along the user
            shell.run("monitor left screens/diamonds", username)

        end
     end
    save()
end

-- This function draws the page for the load game page
local function drawLoadGame()
    paintutils.drawFilledBox(0, 0, w, h, colors.black)
    term.setTextColour(colours.white)
    term.setBackgroundColor(colors.cyan)

    term.setCursorPos(1, 1)
    term.write("      ")
    term.setCursorPos(1, 2)
    term.write(" Back ")
    term.setCursorPos(1, 3)
    term.write("      ")

    term.setBackgroundColor(colors.black)
    term.setCursorPos(20, 7)
    term.write("Load Game")

    term.setCursorPos(0,8)
    local x, y = term.getCursorPos()
    x = math.max(math.floor((w / 2) - (15)), 0)
    term.setCursorPos(x,y)
    term.write("(Please type in the computer)")

    term.setCursorPos(15, 10)
    term.write("Username: ")
    local username = read()

    term.setCursorPos(15, 12)
    term.write("Password: ")
    local password = read("*")

    -- This function will load the user from their save file
    local function load()

        -- If the users file exists, load the save
        if fs.exists("users/" .. username .. "_save") then

            -- Load the users save file
            local hRead = fs.open("users/" .. username .. "_save", "r")

            -- Get the users hashed password and salt
            if hRead then
                readPass = hRead.readLine()
                readSalt = hRead.readLine()
            end

            -- Hash the inputted password with the users salt
            hashedPass = sha.pbkdf2(password, readSalt, 16):toHex()

            -- If the hashed inputted password is the same as the saved one, load the users game
            if readPass == hashedPass then
                shell.run("monitor left screens/diamonds", username)
            else

                -- If the password is not correct, let the user know and restart the load function
                term.setCursorPos(13, 15)
                term.clearLine()
                term.write("That password was incorrect")

                term.setCursorPos(15, 10)
                term.clearLine()

                term.setCursorPos(15, 12)
                term.clearLine()

                term.setCursorPos(15, 10)
                term.write("Username: ")
                local username = read()

                term.setCursorPos(15, 12)
                term.write("Password: ")
                local password = read("*")

                load()
            end
        else

            -- If the user does not have a save file, let the user know and restart the load function
            term.setCursorPos(13, 15)
            term.clearLine()
            term.write("That user does not exist!")

            term.setCursorPos(15, 10)
            term.clearLine()

            term.setCursorPos(15, 12)
            term.clearLine()

            term.setCursorPos(15, 10)
            term.write("Username: ")
            local username = read()

            term.setCursorPos(15, 12)
            term.write("Password: ")
            local password = read("*")

            load()

        end
    end

    load()
end

-- This function draws the page for the leaderboard page
local function drawLeaderboard()
    paintutils.drawFilledBox(0, 0, w, h, colors.black)
    term.setTextColour(colours.white)
    term.setBackgroundColor(colors.cyan)

    term.setCursorPos(1, 1)
    term.write("      ")
    term.setCursorPos(1, 2)
    term.write(" Back ")
    term.setCursorPos(1, 3)
    term.write("      ")

    term.setBackgroundColor(colors.black)
    term.setCursorPos(20, 5)
    term.write("Leaderboard")

    -- If the users file exists, load it
    if fs.exists("users/" .. "users") then

        -- Load the file that contains all of the usernames
        local userRead = fs.open("users/" .. "users", "r")

        -- Get all of the usernames
        local lines = {}
        while true do
            local line = userRead.readLine()

            if not line then break end

            -- Add the diamonds and the username into a table
            local fileRead = fs.open("saves/" .. line .. "_save_file", "r")
            local cps = tonumber(fileRead.readLine())
            local diamonds = tonumber(fileRead.readLine())
            fileRead.close()

            lines[diamonds] = line
        end

        -- Sort all of the users by highest score
        function getKeysSortedByValue(tbl, sortFunction)
            local keys = {}
            for key in pairs(tbl) do
                table.insert(keys, key)
            end

            table.sort(keys, function(a, b)
                return sortFunction(tbl[a], tbl[b])
            end)

            return keys
        end

        -- Sort the users table
        local userTable = getKeysSortedByValue(lines, function(a, b) return a > b end)

        local count = 0

        -- Display the top 5 users and their scores
        for _, key in pairs(userTable) do
            count = count + 1
            if count <= 5 then
                term.setCursorPos(15, 7 + count * 2)
                term.write(count .. ". " .. displayNumber(key) .. " " .. lines[key])
            else
                break
            end

        end

    else

        -- If no users have played yet, display that instead
        term.setCursorPos(12, 9)
        term.write("No scores have been recorded")
    end
end

drawTitle()

-- Get the touch inputs and redirect accordingly
while true do

    local event, side, x, y = os.pullEventRaw()

    if event == "monitor_touch" or event == "mouse_click" then

        if page == "title" then

            if ((x >= 13 and x <= 22) and (y >= 16 and y <= 18)) then
                page = "new"
                drawNewGame()
            elseif ((x >= 27 and x <= 37) and (y >= 16 and y <= 18)) then
                page = "load"
                drawLoadGame()
            elseif ((x >= 45 and x <= 47) and (y >= 16 and y <= 18)) then
                page = "leaderboard"
                drawLeaderboard()
            end
         elseif page == "new" then
            if ((x >= 1 and x <= 6) and (y >= 1 and y <= 3)) then
                page = "title"
                drawTitle()
            end
         elseif page == "load" then
            if ((x >= 1 and x <= 6) and (y >= 1 and y <= 3)) then
                page = "title"
                drawTitle()
            end
         elseif page == "leaderboard" then
            if ((x >= 1 and x <= 6) and (y >= 1 and y <= 3)) then
                page = "title"
                drawTitle()
            end
         end
    end
end