Slot machine

--[[
Copyright 2015 Max Thor <thormax5@gmail.com>

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
   ]]--

-- Variables

local color = false
local creds = 0
local plusX = 0
local w, h = term.getSize()

function cWrite(txt,y)
    term.setCursorPos(math.floor(w-string.len(txt))/2+plusX, h/2)
    term.write(txt)
    plusX = plusX+1
end

function cWrite2(txt, y)
    term.setCursorPos(math.floor(w-string.len(txt))/2, y)
    term.write(txt)
end

function win(amt)
    creds = creds+amt
    if(color) then
        term.setTextColor(16)
        cWrite2("Won! "..amt, 2)
    else
        cWrite2("Won! "..amt, 2)
    end
end

function save()
    local h = fs.open(".slots/save", "w")
    h.write(creds)
    h.close()
end

function ui()
    if(color) then
        term.setCursorPos(1,1)
        term.setBackgroundColor(256)
        term.clearLine()
        term.setTextColor(1)
        term.write("Credits: "..creds)
        term.setBackgroundColor(32768)
    else
        term.setCursorPos(1,1)
        term.clearLine()
        term.setTextColor(1)
        term.write("Credits: "..creds)
    end
end

function spin()
    term.clear()
    local a = math.random(0, 3)
    local b = math.random(0, 3)
    local c = math.random(0, 3)

    if(a == 1) then
        if(color) then
            term.setTextColor(32)
            cWrite("X", 0)
        else
            cWrite("X", 0)
        end
    elseif(a == 2) then
        if(color) then
            term.setTextColor(2)
            cWrite("$", 0)
        else
            cWrite("$", 0)
        end
    elseif(a == 3) then
        if(color) then
            term.setTextColor(8)
            cWrite("O", 0)
        else
            cWrite("O", 0)
        end
    else
        if(color) then
            term.setTextColor(16384)
            cWrite("-",0)
        else
            cWrite("-", 0)
        end
    end

    if(b == 1) then
        if(color) then
            term.setTextColor(32)
            cWrite("X", 0)
        else
            cWrite("X", 0)
        end
    elseif(b == 2) then
        if(color) then
            term.setTextColor(2)
            cWrite("$", 0)
        else
            cWrite("$", 0)
        end
    elseif(b == 3) then
        if(color) then
            term.setTextColor(8)
            cWrite("O", 0)
        else
            cWrite("O", 0)
        end
    else
        if(color) then
            term.setTextColor(16384)
            cWrite("-",0)
        else
            cWrite("-", 0)
        end
    end

    if(c == 1) then
        if(color) then
            term.setTextColor(32)
            cWrite("X", 0)
        else
            cWrite("X", 0)
        end
    elseif(c == 2) then
        if(color) then
            term.setTextColor(2)
            cWrite("$", 0)
        else
            cWrite("$", 0)
        end
    elseif(c == 3) then
        if(color) then
            term.setTextColor(8)
            cWrite("O", 0)
        else
            cWrite("O", 0)
        end
    else
        if(color) then
            term.setTextColor(16384)
            cWrite("-",0)
        else
            cWrite("-", 0)
        end
    end

    if(a == 1 and b == 1 and c == 1) then
        win(5)
    elseif(a == 2 and b == 2 and c == 2) then
        win(10)
    elseif(a == 3 and b == 3 and c == 3) then
        win(15)
    end

    plusX = 0
    ui()
end

function main()
    term.clear()
    ui()
    while true do
        e, p1 = os.pullEventRaw()
        if(e == "key") then
            if(p1 == 57) then
                if(creds > 0) then
                    creds = creds-1
                    spin()
                end
            elseif(p1 == 1) then
                save()
                os.queueEvent("terminate")
            end
        elseif(e == "terminate") then
            term.setTextColor(1)
            term.setBackgroundColor(32768)
            term.clear()
            plusX = 0
            cWrite("Thanks for playing!")
            break
        end
    end
end


function setup()
    if(term.isColor()) then
        color = true
    end
    if(fs.exists(".slots/save")) then
        local h = fs.open(".slots/save", "r")
        creds = tonumber(h.readAll())
        h.close()
        main()
    else
        fs.makeDir(".slots")
        local h = fs.open(".slots/save", "w")
        h.write("10")
        h.close()
    end
end

setup()