Ball game type thing

--this is a game
--copyright of BlueTide Programs.inc, Benedict Allen, and all members of BlueTide Programs.inc
--if you wish to use this program please contact Benedict Allen(awsumben13 on cc forums) and make sure you give the credit to BlueTide Programs
--usability functions
function clear(x,y)
if x == nil or y == nil then
  term.clear()
  term.setCursorPos(1,1)
else
  term.clear()
  term.setCursorPos(x,y)
end
end
function writePos(x,y,text)
term.setCursorPos(x,y)
term.write(text)
end
function clearPrint(x,y,text)
term.clear()
term.setCursorPos(x,y)
term.write(text)
end
function reset(file, x, y)
if fs.exists(file) then
  h = fs.open(file, "w")
  h.write("")
  h.close()
  term.setCursorPos(x,y)
  term.write("File reset")
  sleep(2)
else
  term.setCursorPos(x,y)
  term.write("file not found")
  sleep(2)
end
end
function tip(help)
while true do
  clear()
  print(help)
  writePos(1,17,"press enter to exit")
  event, key = os.pullEvent()
  if key == 28 then break
  end
end
end
function drawBox(x,y,z,n,clear)
if clear == false then
  for k = 1,n-y do
   for i = 1,z-x do
	writePos(x+i,y+k," ")
   end
  end
end
writePos(x,y," ")
term.setCursorPos(x+1,y)
for i = 1,(z-x)-1 do
  write(" ")
end
writePos(z,y," ")
term.setCursorPos(x+1,n)
for i = 1,(z-x)-1 do
  write(" ")
end
for i = 1,(n-y)-1 do
  writePos(x,y+i," ")
end
for i = 1,(n-y)-1 do
  writePos(z,y+i," ")
end
writePos(x,n," ")
writePos(z,n," ")
end
function split(str, pat)
   local t = {}
   local fpat = "(.-)" .. pat
   local last_end = 1
   local s, e, cap = str:find(fpat, 1)
   while s do
	  if s ~= 1 or cap ~= "" then
  table.insert(t,cap)
	  end
	  last_end = e+1
	  s, e, cap = str:find(fpat, last_end)
   end
   if last_end <= #str then
	  cap = str:sub(last_end)
	  table.insert(t, cap)
   end
   return t
end
function fill(x,y,z,n,colour)
for i = y,n do
  for k = x,z do
   term.setBackgroundColour(colour)
   writePos(k,i," ")
  end
end
end
function reader(x,y,limit)
t = {}
k = ""
variable = 0
while true do
  variable = 0
  event, p1, p2, p3 = os.pullEvent()
  if event == "click" then
   getItemSel()
   break
  elseif p1 == 15 and screenSel == 2 then
   screenSel = 1
   t = {}
   break
  elseif event == "rednet_message" then
   receive()
  elseif event == "char" then
   table.insert(t,p1)
  elseif p1 == 28 then
   break
  elseif p1 == 14 then
   table.remove(t,#t)
  end
  for i = x-1,x+limit do
   term.setBackgroundColour(colours.lightBlue)
   writePos(i,y," ")
  end
  if #t < limit then
   for i = 1,#t do
	writePos((x-1)+i,y,t[i])
	term.setCursorBlink(true)
   end
  else
   for i = #t-limit,#t do
	variable = variable+1
	writePos(((x-1)+variable)-1,y,t[i])
	term.setCursorBlink(true)
   end
  end
end
for i = 1,#t do
  k = k..t[i]
end
return k
end
function defaultColours()
term.setBackgroundColour(colours.white)
term.setTextColour(colours.black)
end
function sleep(time)
while true do
  if time ~= nil then
   os.startTimer(time)
  end
  event, key = os.pullEvent()
  if time == nil then
   break
  elseif event == "timer" then
   break
  end
end
end
--end
--programs functions
function drawScreen()
clear()
term.setBackgroundColour(colours.black)
drawBox(1,1,51,17)
drawBox(1,17,51,19)
defaultColours()
for i = 1,#items do
  writePos(items[i].xPos,items[i].yPos,items[i].toPrint)
  --writePos(1,i,items[i].xPos.."-"..items[i].yPos.." - - - "..items[i].yChange)
end
writePos(2,18,"Speed = "..11-time.." - Number of items = "..#items)
writePos(37,18,"- Del - Reset")
end
function move()
for i = 1,#items do
  for k = 1,#items do
   if items[i].xPos == items[k].xPos-1 and (items[i].yPos == items[k].yPos or items[i].yPos == items[k].yPos+1 or items[i].yPos == items[k].yPos-1) then
	if items[i].xChange == 1 then
	 items[i].xChange = -1
	end
   end
   if items[i].xPos == items[k].xPos+1 and (items[i].yPos == items[k].yPos or items[i].yPos == items[k].yPos+1 or items[i].yPos == items[k].yPos-1) then
	if items[i].xChange == -1 then
	 items[i].xChange = 1
	end
   end
   if items[i].yPos == items[k].yPos-1 and (items[i].xPos == items[k].xPos or items[i].xPos == items[k].xPos-1 or items[i].xPos == items[k].xPos+1) then
	if items[i].yChange == 1 then
	 items[i].yChange = -1
	end
   end
   if items[i].yPos == items[k].yPos+1 and (items[i].xPos == items[k].xPos or items[i].xPos == items[k].xPos-1 or items[i].xPos == items[k].xPos+1) then
	if items[i].yChange == -1 then
	 items[i].yChange = 1
	end
   end
  end
end
for i = 1,#items do
  if items[i].xPos <= 2 and items[i].xChange < 0 then
   items[i].xChange = tonumber(string.sub(tostring(items[i].xChange),2,3))	  
  elseif items[i].xPos >= 50 and items[i].xChange > 0 then
   items[i].xChange = items[i].xChange-(2*items[i].xChange)
  end
  if items[i].yPos <= 2 and items[i].yChange < 0 then
   items[i].yChange = tonumber(string.sub(tostring(items[i].yChange),2,3))	  
  elseif items[i].yPos >= 16 and items[i].yChange > 0 then
   items[i].yChange = items[i].yChange-(2*items[i].yChange)
  end
end
for i = 1,#items do
  items[i].xPos = items[i].xPos+items[i].xChange
  items[i].yPos = items[i].yPos+items[i].yChange
end
end
function runApp()
while loopBreaker ~= true do
  for i = 1,#items do
   items[i].height = 15-items[i].yPos
  end
  drawScreen()
  move()
  if timerStarted == false then
   os.startTimer(time)
   timerStarted = true
  end
  while true do
   drawScreen()
   event, p1, p2, p3 = os.pullEvent()
   if event == "key" and (p1 == 28 or p1 == 14) then
	loopBreaker = true
	break
   elseif event == "char" then
	icon = p1
   elseif event == "mouse_click" and #items < itemLimit and p1 == 2 and p3 < 16 and p3 > 1 and p2 > 1 and p2 < 51 then
	items[#items+1] = {toPrint = icon;xPos = p2;yPos = p3;xChange = 1;yChange = dir; height = 15-p3}
   elseif event == "mouse_click" and #items < itemLimit and p1 == 1 and p3 < 16 and p3 > 1 and p2 > 1 and p2 < 51 then
	items[#items+1] = {toPrint = icon;xPos = p2;yPos = p3;xChange = -1;yChange = dir;height = 15-p3}
   elseif event == "mouse_click" and p3 == 18 and p2 > 38 and p2 < 42 and #items > 1 then
	items[#items] = nil
	break
   elseif event == "mouse_click" and p3 == 18 and p2 > 44 and p2 < 50 then
	for i = 2,#items do
	 items[i] = nil
	end
	break
   elseif event == "mouse_scroll" and p1 == -1 then
	dir = -1
   elseif event == "mouse_scroll" and p1 == 1 then
	dir = 1
   elseif p1 == 205 and time > 1.04 then
	time = time-1
   elseif p1 == 203 and time < 9.01 then
	time = time+1
   elseif p1 == 200 and time > 0.09 then
	time = time-0.05
   elseif p1 == 208 and time < 9.96 then
	time = time+0.05
   elseif p1 == 208 and time < 0.09 then
	time = 0.0
   elseif p1 == 205 and time < 1.05 then
	time = 0.0
   elseif p1 == 203 and time > 9 then
	time = 10
   elseif p1 == 200 and time > 9.95 then
	time = 10
   elseif p1 == 15 then
	time = 1
	timerStarted = false
	break
   elseif event == "timer" then
	timerStarted = false
	break
   elseif p1 == 57 then
	while true do
	 for i = 1,#items do
	  writePos(items[i].xPos-1,items[i].yPos,"["..items[i].toPrint.."]")
	 end
	 event, key = os.pullEvent("key")
	 if key == 57 then
	  timerStarted = false
	  break
	 end
	end
	break
   end
  end
end
end
--end
--variables
dir = 1
time = 0
icon = "O"
itemLimit = 30
loopBreaker = false
timerStarted = false
items = {
{toPrint = "O";
  xPos = 2;
  yPos = 2;
  xChange = 1;
  yChange = 1;
  p = true
};
{toPrint = "O";
  xPos = 3;
  yPos = 2;
  xChange = 1;
  yChange = 1;
  p = true
};
{toPrint = "O";
  xPos = 4;
  yPos = 2;
  xChange = 1;
  yChange = 1;
  p = true
};
}
--end
--code
defaultColours()
runApp()
--end