OpenComputers Button Library

-- Please forgive the problems with this script, I wrote it a long time ago when I was learning Lua.

component = require("component")
term = require("term")
text = require("text")
event = require("event")

button = {}

local function splitMessage(message, del) -- Splits a string by del (delimiter)
  if not text then text = require("text") end
  -- Default to whitespace
  if del == nil then
    del = "%s"
  end

  local t={} ; i=1
  for str in string.gmatch(message, "([^"..del.."]+)") do
    t[i] = str
    i = i + 1
  end
  return t
end

-- Generates a new button
-- Usage:
-- buttonList = button.newButton(buttonList: table, label: string, action: function, width: number, height: number, paddings: string[ e.g. "left:right:top:bottom"], colorSet: string [e.g. "0x00AA00:0xAA0000"])
function button.newButton(buttonList, label, action, actionArgT, width, height, paddings, colorSet, xBorder, yBorder) -- format colors as color:color
  local tX, tY = component.gpu.getResolution()
  local buttonData = {}

  -- Screen margins (defaults for first button)
  local minX = 1
  local maxX = 0
  local minY = 2
  local maxY = 0

  -- Determine button placement
  if buttonList[#buttonList] then                                  -- Add button to existing table
    -- Row end?
	local startX = buttonList[#buttonList].spatialT.maxX + width

	if startX > tX then                                            -- New row
	  minY = buttonList[#buttonList].spatialT.maxY
	  minX = minX
	else                                                            -- Same row
	  minX = buttonList[#buttonList].spatialT.maxX
	  minY = buttonList[#buttonList].spatialT.minY
	end
  else                                                              -- Initial button on table
    minX = minX
	minY = minY
  end

  local maxX = minX + width
  local maxY = minY + height

  -- Set padding
  local paddingT = splitMessage(paddings, ":")

  -- Set render area
  local xMinRender = minX + (tonumber(text.trim(paddingT[1])) * 2)
  local xMaxRender = maxX - (tonumber(text.trim(paddingT[2])) * 2)
  local yMinRender = minY + tonumber(text.trim(paddingT[3]))
  local yMaxRender = maxY - tonumber(text.trim(paddingT[4]))

  local renderWidth = xMaxRender - xMinRender
  local renderHeight = yMaxRender - yMinRender

  -- Set colors
  local colorT = splitMessage(colorSet, ":")


  local spatialT =
  {
  minX=minX,
  maxX=maxX,
  minY=minY,
  maxY=maxY,

  width=width,
  height=height,

  xMinPadding=xMinPadding,
  xMaxPadding=xMaxPadding,
  yMinPadding=yMinPadding,
  yMaxPadding=yMaxPadding,

  xMinRender=xMinRender,
  xMaxRender=xMaxRender,
  yMinRender=yMinRender,
  yMaxRender=yMaxRender,

  renderWidth=renderWidth,
  renderHeight=renderHeight,
  }

  local buttonData =
  {
    label = label,
    action = action,
	actionArgT=actionArgT,
    state = false,
	colorT = colorT,
    spatialT=spatialT,
	xBorder=xBorder,
	yBorder=yBorder,
    }

  for i=1, #buttonData do
    assert(buttonData[i], "Missing buttonData "..i)
  end
  for i=1, #spatialT do
    assert(spatialT[i], "Missing spatialT"..i)
  end

  table.insert(buttonList, buttonData)
  return buttonList
end

function button.render(buttonData)
  local bG = component.gpu.getBackground()

  -- Create string of spaces
  local spacers = ""
  for i=1, buttonData.spatialT.renderWidth do
    spacers = spacers.." "
  end

  -- Create string of margin spaces for label
  local margin = ""
  for i=1, (buttonData.spatialT.renderWidth - string.len(buttonData.label))/2  do
    margin = margin.." "
  end


    -- Wrap label in margins
  local spacedLabel = margin..buttonData.label..margin
  if string.len(spacedLabel) < buttonData.spatialT.renderWidth then spacedLabel = spacedLabel.." " end


    -- Set color from state
  if buttonData.state then
    component.gpu.setBackground(tonumber(buttonData.colorT[1]))
  else
    component.gpu.setBackground(tonumber(buttonData.colorT[2]))
  end

    -- Write button to terminal
  for i=0, buttonData.spatialT.renderHeight-1 do
    term.setCursor(buttonData.spatialT.xMinRender, buttonData.spatialT.yMinRender+i)

    if i == math.floor((buttonData.spatialT.renderHeight/2)-1) then  -- If we're at the center/high-center
	  term.write(spacedLabel)
	else
	  term.write(spacers)
	end
  end

  component.gpu.setBackground(bG)
end

function button.renderAll(buttonList)
  term.clear()
  for i=1, #buttonList do
    button.render(buttonList[i])
  end
end

function button.checkTouch(buttonList, x, y)
  local buttonList = buttonList
  local cButton = {}

  local onButton = false
  for i=1, #buttonList do
    if (x >= buttonList[i].spatialT.xMinRender) and (x <= buttonList[i].spatialT.xMaxRender) and (y >= buttonList[i].spatialT.yMinRender) and (y <= buttonList[i].spatialT.yMaxRender) then
	  onButton = true

	  -- Execute function with current button as arg
	  -- Make sure the function returns current button table
	  cButton = buttonList[i].action(buttonList[i], buttonList[i].actionArgT)

	  -- Rewrite current button with table returned by action
	  buttonList[i] = cButton
	end
  end
  return buttonList, cButton, onButton
end

function button.toggle(cButton, argT)
  if cButton.state then cButton.state = false else cButton.state = true end
  return cButton
end

function button.setAllStates(buttonList, argT)
  local buttonList = buttonList
  for i=1, #buttonList do
    buttonList[i].state = argT.state
  end
  return buttonList
end

return button