ComputerCraft Tutorial: btn_ctrl0_2

-- ############################################
-- btn_ctrl
-- version 0.2
-- http://hevohevo.hatenablog.com/

-- ################## config ##################
CtrlMonSide = "top"
CtrlMon = peripheral.wrap(CtrlMonSide)
----------------------------
-- btns[1]  btns[2]  btns[3]
-- btns[4]  btns[5]  btns[6]
-- btns[7]  btns[8]  btns[9]
----------------------------
Btns = {}
Btns[1] = {name="atk",   cmd="turtle.attack()"}
Btns[2] = {name="dig",   cmd="turtle.dig()"}
Btns[3] = {name="place", cmd="turtle.place()"}
Btns[4] = {name="<=",    cmd="turtle.turnLeft()"}
Btns[5] = {name="suck",  cmd="turtle.suck()"}
Btns[6] = {name="=>",    cmd="turtle.turnRight()"}
Btns[7] = {name="<sel", cmd="turtle.selectPrev()"}
Btns[8] = {name="sel1",  cmd="turtle.select(1)"}
Btns[9] = {name="sel>", cmd="turtle.selectNext()"}

-- ################## functions ###############
-- new turtle commands
turtle.select(1)
CurrentSlot = 1 -- for retaining current selected slot number
OrgSelectCmd = turtle.select -- for redefining function

function turtle.select(slot) -- redefine function
  CurrentSlot = slot
  OrgSelectCmd(slot)
  print("  slot: ", slot)
end

function return1_16(num)
  if (num % 16) == 0 then
    return 16
  else
    return (num % 16)
  end
end

function turtle.selectNext() -- define new function
  turtle.select(return1_16(CurrentSlot + 1))
end

function turtle.selectPrev() -- define new-function
  turtle.select(return1_16(CurrentSlot - 1))
end

-- evaluate a function-string
-- ex. eval("turltle.select(1)")
function eval(s)
  print("  ",s)
  assert(loadstring(s))()
end

-- return btns-table
function makeNineButtons(ctrl_mon, Btns)
  local mon_w, mon_h = ctrl_mon.getSize()
  local btn_w = math.floor(mon_w/3)
  local btn_h = math.floor(mon_h/3)
  local btns = {}
  local i=1 -- table index
  for row=1,3 do
    for col=1,3 do
      btns[i] = {
        name=Btns[i]["name"], cmd=Btns[i]["cmd"],
        min_x = 1+(btn_w)*(col-1), min_y = 1+(btn_h)*(row-1),
        max_x = btn_w*col, max_y = btn_h*row}
      i = i+1
    end
  end
  return btns
end

function drowButtons(mon, buttons)
  for i,b in pairs(buttons) do
    local center_x = math.floor((b.min_x + b.max_x)/2)
    local center_y = math.floor((b.min_y + b.max_y)/2)
    local center_label = math.floor(string.len(b.name)/2)
    mon.setCursorPos(center_x - center_label, center_y)
    mon.write(b.name)
  end
end

-- whichButton(buttons, 1, 1) => btn     (btn-table)
--                            => false   (don't pushed)
function whichButton(buttons, x, y)
  local function within(min_num, max_num, num)
          return (min_num <= num and max_num >= num)
        end
  local pushed_btn = false

  for i,v in pairs(buttons) do
    if within(v.min_x, v.max_x, x) and within(v.min_y, v.max_y, y) then
      pushed_btn = v
      break
    end
  end

  return pushed_btn
end

-- event_name, pushed_btn = pullPushButtonEvent(buttons_table, "top")
function pullPushButtonEvent(buttons, mon_dir)
  local pushed_btn = false
  repeat
    local event, dir, x, y = os.pullEvent("monitor_touch")
    if mon_dir == dir  then
      pushed_btn = whichButton(buttons, x, y)
    end
  until  pushed_btn

  return "push_button", pushed_btn
end

-- ################## main #####################
-- init ctrl monitor
CtrlMon.setTextScale(0.5)
CtrlMon.clear()

-- make buttons and drow on ctrl monitor
local mon_btns = makeNineButtons(CtrlMon, Btns)
drowButtons(CtrlMon, mon_btns)

-- main loop
while true do
  local event_name, pushed_btn = pullPushButtonEvent(mon_btns, CtrlMonSide)
  if event_name == "push_button" then
    print("pushed: ",pushed_btn.name)
    eval(pushed_btn.cmd)
  end

  sleep(0) -- "monitor_touch" event is too sensitive.
end