--[[Note: The original codebase is not mine, please refer the link below]]--
--[[Caesar Cipher example to be integrated with Module API.]]--
--[[Logic of cipher taken from - http://www.rosettacode.org/wiki/Caesar_cipher#Lua]]--
--[[As a supporter of free software, and don't wanna reinvent the wheel for no reason,
I choose to take an existing codebase and integrate it with simple Module API]]--
--[[Target: lua feature (tfm). For luaj (java), and luajit(just-in-time) compiler, running on nginx currently]]--
--[[Modified by: Pydlua, credits to Rosettacode.org]]--

-- TO USE: !messagetoencrypt
-- Change the key to any number (max: 25) (default is 7)

local function encrypt(text, key)
return text:gsub("%a", function(t)
local base = (t:lower() == t and string.byte('a') or string.byte('A'))

local r = t:byte() - base
r = r + key
r = r%26 -- works correctly even if r is negative
r = r + base
return string.char(r)
end)
end

local function decrypt(text, key)
return encrypt(text, -key)
end

caesar = {
encrypt = encrypt,
decrypt = decrypt,
}

-- change the addTextArea target player, to send to specific player
-- By default is nil that is all player available in the room
--[[ Example to add specific player:

newPlayer="your_friend)
ui.addTextArea(1,"Encrypted text: " .. encrypted,newPlayer,500,180,500,200,0x324650,0x212F36,0.8,true)
ui.addPopup(1,0,decrypted,newPlayer,-160,180,500,true)
by adding this, this will make your friend also see the window
]]--

key=7
target="Pydlua"
function eventChatCommand(target, text)
local encrypted = caesar.encrypt(text, key)
local decrypted = caesar.decrypt(encrypted, key)
print("Original message: "..text)
print("Encrypted text: "..encrypted)
print("Decrypted message: "..decrypted)
ui.addTextArea(1,"Encrypted text: " .. encrypted,nil,500,180,500,200,0x324650,0x212F36,0.8,true)
ui.addPopup(1,0,"Decrypted text: "..decrypted,nil,-160,180,500,true)
end