touchAPI

local function setupLabel(buttonLen, minY, maxY, name)
  local labelTable = {}
  if type(name) == "table" then
    for i = 1, #name do
      labelTable[i] = name[i]
    end
    name = name.label
  elseif type(name) == "string" then
    local buttonText = string.sub(name, 1, buttonLen - 2)
    if #buttonText < #name then
      buttonText = " "..buttonText.." "
    else
      local labelLine = string.rep(" ", math.floor((buttonLen - #buttonText) / 2))..buttonText
      buttonText = labelLine..string.rep(" ", buttonLen - #labelLine)
    end
    for i = 1, maxY - minY + 1 do
      if maxY == minY or i == math.floor((maxY - minY) / 2) + 1 then
        labelTable[i] = buttonText
      else
        labelTable[i] = string.rep(" ", buttonLen)
      end
    end
  end
  return labelTable, name
end

local Button = {
  draw = function(self)
    local old = term.redirect(self.mon)
    term.setTextColor(colors.white)
    term.setBackgroundColor(colors.black)
    term.clear()
    for name, buttonData in pairs(self.buttonList) do
      if buttonData.active then
        term.setBackgroundColor(buttonData.activeColor)
        term.setTextColor(buttonData.activeText)
      else
        term.setBackgroundColor(buttonData.inactiveColor)
        term.setTextColor(buttonData.inactiveText)
      end
      for i = buttonData.yMin, buttonData.yMax do
        term.setCursorPos(buttonData.xMin, i)
        term.write(buttonData.label[i - buttonData.yMin + 1])
      end
    end
    if old then
      term.redirect(old)
    else
      term.restore()
    end
  end,
  add = function(self, name, func, xMin, yMin, xMax, yMax, inactiveColor, activeColor, inactiveText, activeText)
    local label, name = setupLabel(xMax - xMin + 1, yMin, yMax, name)
    if self.buttonList[name] then error("button already exists", 2) end
    local x, y = self.mon.getSize()
    if xMin < 1 or yMin < 1 or xMax > x or yMax > y then error("button out of bounds", 2) end
    self.buttonList[name] = {
      func = func,
      xMin = xMin,
      yMin = yMin,
      xMax = xMax,
      yMax = yMax,
      active = false,
      inactiveColor = inactiveColor or colors.red,
      activeColor = activeColor or colors.lime,
      inactiveText = inactiveText or colors.white,
      activeText = activeText or colors.white,
      label = label,
    }
    for i = xMin, xMax do
      for j = yMin, yMax do
        if self.clickMap[i][j] ~= nil then
          --undo changes
          for k = xMin, xMax do
            for l = yMin, yMax do
              if self.clickMap[k][l] == name then
                self.clickMap[k][l] = nil
              end
            end
          end
          self.buttonList[name] = nil
          error("overlapping button", 2)
        end
        self.clickMap[i][j] = name
      end
    end
  end,
  remove = function(self, name)
    if self.buttonList[name] then
      local button = self.buttonList[name]
      for i = button.xMin, button.xMax do
        for j = button.yMin, button.yMax do
          self.clickMap[i][j] = nil
        end
      end
      self.buttonList[name] = nil
    end
  end,
  run = function(self)
    while true do
      self:draw()
      local event = {self:handleEvents(os.pullEvent(self.side == "term" and "mouse_click" or "monitor_touch"))}
      if event[1] == "button_click" then
        self.buttonList[event[2]].func()
      end
    end
  end,
  handleEvents = function(self, ...)
    local event = {...}
    if #event == 0 then event = {os.pullEvent()} end
    if (self.side == "term" and event[1] == "mouse_click") or (self.side ~= "term" and event[1] == "monitor_touch" and event[2] == self.side) then
      local clicked = self.clickMap[event[3]][event[4]]
      if clicked and self.buttonList[clicked] then
        return "button_click", clicked
      end
    end
    return unpack(event)
  end,
  toggleButton = function(self, name, noDraw)
    self.buttonList[name].active = not self.buttonList[name].active
    if not noDraw then self:draw() end
  end,
  flash = function(self, name, duration)
    self:toggleButton(name)
    sleep(tonumber(duration) or 0.15)
    self:toggleButton(name)
  end,
  rename = function(self, name, newName)
    self.buttonList[name].label, newName = setupLabel(self.buttonList[name].xMax - self.buttonList[name].xMin + 1, self.buttonList[name].yMin, self.buttonList[name].yMax, newName)
    if not self.buttonList[name] then error("no such button", 2) end
    if name ~= newName then
      self.buttonList[newName] = self.buttonList[name]
      self.buttonList[name] = nil
      for i = self.buttonList[newName].xMin, self.buttonList[newName].xMax do
        for j = self.buttonList[newName].yMin, self.buttonList[newName].yMax do
          self.clickMap[i][j] = newName
        end
      end
    end
    self:draw()
  end,
}

function new(monSide)
  local buttonInstance = {
    side = monSide or "term",
    mon = monSide and peripheral.wrap(monSide) or term.current(),
    buttonList = {},
    clickMap = {},
  }
  local x, y = buttonInstance.mon.getSize()
  for i = 1, x do
    buttonInstance.clickMap[i] = {}
  end
  setmetatable(buttonInstance, {__index = Button})
  return buttonInstance
end