CC:UserDatabase

local DB = "disk/.database";
local USERS = "disk/.database/users";
local base64Map = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
local user;

--INITIALIZE
if(not fs.isDir(DB))then
  fs.makeDir(DB);
  print("Database Created: "..tostring(fs.isDir(DB)));
  fs.makeDir(USERS);
  print("User Database Created: "..tostring(fs.isDir(USERS)));
else
  print("Database found... continuing...");
end

--USER FUNCTIONS

function createUser(name, password)
  local exists = userExists(name)
  if(not exists)then
    local fileData;
    fileData = fs.open(USERS.."/"..name..".dat","w");
    fileData.writeLine("[PASSWORD]");
    fileData.writeLine(toBase64(password));
    fileData.close();
    return true; --USER CREATED
  end
  return false; --USER EXISTS ALREADY
end

function loginAs(name, password)
  local exists = userExists(name)
  if(exists)then
    fileData = fs.open(USERS.."/"..name..".dat","r");
    local pass;
    local data = {USER = name, DATABASES = {}};
    repeat
      local dataObj = fileData.readLine();
      if(data=="[PASSWORD]")then
        pass = fileData.readLine();
      elseif(data=="[DATABASES]")then
        repeat
          db = fileData.readLine();
          if(db~=nil and db~="&0")then
            table.insert(dataObj.DATABASES, DB.."/"..db);
          end
        until( db == "&0" );
      end
    until( data == nil );
    fileData.close();
    if( pass == toBase64(password) )then
      user = dataObj;
      return true;
    end
    return false;
  end
  return false;
end

function userExists(name)
  if(fs.exists(USERS.."/"..name..".dat"))then
    return true; --USER DOES EXIST
  end
  return false; --USER DOESN'T EXIST
end

--DATA MANIPULATION
function toBase64(str)
  local bits = {};
  local char;
  for i = 1,#str do
    char = str:sub(i,i);
    table.insert(bits,char:byte());
  end
  local bitsTotal = #str*8;
  local bitsNeeded = 6;
  local bitsLeft = 8;
  local leftover = false;
  local output = "";
  while(#bits > 0)do
    local value;
    if(bitsLeft>=bitsNeeded)then --all in ove val
      local byte = bits[1];
      value = bit.blogic_rshift(byte,bitsLeft-bitsNeeded);
      byte = byte-bit.blshift(value,bitsLeft-bitsNeeded);
      if(bitsLeft==bitsNeeded)then
        table.remove(bits,1);
        bitsNeeded = 6;
        bitsLeft = 8;
      else
        bits[1] = byte;
        bitsLeft = bitsLeft-bitsNeeded;
        bitsNeeded = 6;
      end
    else --we have few bits left
      local byte = bits[1];
      value = bit.blshift(byte,6-bitsLeft);
      value = bit.band(value,127);
      table.remove(bits,1);
      byte = bits[1];
      bitsNeeded = 6-bitsLeft;
      bitsLeft = 8-bitsNeeded;
      if(byte~=nil)then
        local sv = bit.blogic_rshift(byte, 8-bitsNeeded);
        value = value + sv;
        bits[1] = bits[1]-bit.blshift(sv,8-bitsNeeded);
        bitsNeeded = 6;
      else
        leftover = true;
      end
    end
    output = output..base64Map:sub(value+1,value+1);
  end
  if(leftover)then
    print(bitsNeeded.."/"..bitsLeft);
    if(bitsNeeded<bitsLeft)then
      output = output.."=";
    else
      output = output.."==";
    end
  end
  return output;
end