--Button API by Tobolobo (M3inNam3)

--Side HAS to be changed manually!!!
local monitor = peripheral.wrap("left")
local button = {}
local buttoncount = 0

--privateDrawButton: A function that should
--only be used by the API itself. It draws
--a button.
function privateDrawButton(colour, text, xMin, xMax, yMin, yMax)
  --Calculate difference
  local ydif = yMax - yMin
  local xdif = xMax - xMin
  --Draw button
  monitor.setBackgroundColor(colour)
  for i = yMin, yMax do
    for j = xMin, xMax do
      monitor.setCursorPos(j, i)
      monitor.write(" ")
    end
  end
  --Write text
  monitor.setCursorPos(xMin + math.floor((xdif + 1 - string.len(text)) / 2), yMin + math.floor(ydif / 2))
  monitor.write(text)
  monitor.setBackgroundColor(colors.black)
  return true
end

--register: Registers a single button
--and draws it on the monitor.
function register(text, xMin, xMax, yMin, yMax, notActiveColour, activeColour)
  --Fill button table with new row and insert data
  button[buttoncount] = {}
  --The text shown on the button
  button[buttoncount][0] = text
  --The lowest x value of the button
  button[buttoncount][1] = xMin
  --The highest x value of the button
  button[buttoncount][2] = xMax
  --The lowest y value of the button
  button[buttoncount][3] = yMin
  --The highest y value of the button
  button[buttoncount][4] = yMax
  --Is the button enabled?
  button[buttoncount][5] = true
  --Color when not active(when the button is created)
  if notActiveColour == -1 then
    button[buttoncount][6] = colors.red
  else
    button[buttoncount][6] = notActiveColour
  end
  --Color when active (when the button is pressed once)
  if activeColour == -1 then
    button[buttoncount][7] = colors.green
  else
    button[buttoncount][7] = activeColour
  end
  --Is the button active or not?
  button[buttoncount][8] = false
  --Draw the button
  privateDrawButton(button[buttoncount][6], text, xMin, xMax, yMin, yMax)
  buttoncount = buttoncount + 1
  return buttoncount - 1
end

--redraw: Redraws a single button.
function redraw(id)
  --Check if button exists and is enabled
  if (button[id] == nil) or (button[id][5] == false) then
    return false
  end
  --Get data and draw
  local drawColour = 0
  if button[id][8] == false then
    drawColour = button[id][6]
  else
    drawColour = button[id][7]
  end
  privateDrawButton(drawColour, button[id][0], button[id][1], button[id][2], button[id][3], button[id][4])
  return true
end

--getCollisions: It tests each enabled button
--if the x and y coordinates collide with it!
--It returns the id of the button. So instead
--of overriding buttons you should disable them!
--Flaw here: It can only be colliding with one
--button (the one which registered first). But
--who would let 2 buttons overlap each other?

function getCollisions(x, y)
  --Return -1 if no buttons registered yet
  if buttoncount == 0 then
    return -1
  end
  for i = 0, buttoncount - 1 do
    if button[i][5] == true then
      --Check if it collides with a button
      if (button[i][1] <= x) and (button[i][2] >= x) and (button[i][3] <= y) and (button[i][4] >= y) then
        return i
      end
    end
  end
  return -1
end

--flash: Flashes the button.
function flash(id, seconds)
  if button[id] == nil then
    return false
  end
  switch(id)
  --I hate using os.sleep() in this....
  os.sleep(seconds)
  switch(id)
  return true
end

function exists(id)
  if button[id] == nil then
    return false
  else
    return true
  end
end

--Properties get/set


--setText: Sets the text of the button.
function setText(id, text)
  if button[id] == nil then
    return false
  end
  button[id][0] = text
  redraw(id)
  return true
end

--getText: Gets the text of the button.
function getText(id)
  if button[id] == nil then
    return false
  end
  return button[id][0]
end

--setPosition: Sets the new position of the button.
--The old button will be erased!
function setPosition(id, xMin, xMax, yMin, yMax)
  if button[id] == nil then
    return false
  end
  disable(id)
  if not(xMin == -1) then
    button[id][1] = xMin
  end
  if not(xMin == -1) then
    button[id][2] = xMax
  end
  if not(yMin == -1) then
    button[id][3] = yMin
  end
  if not(yMin == -1) then
    button[id][4] = yMax
  end
  enable(id)
  return true
end

--getPosition: Gets the position of the button.
--Returns an array with left, right, top, bottom
--coordinates starting at 0
function getPosition(id)
  if button[id] == nil then
    return false
  end
  local coords = {}
  for i = 0, 3 do
    coords[i] = button[id][i + 1]
  end
  return coords
end

--enable: Enables a single button.
function enable(id)
  if button[id] == nil then
    return false
  end
  button[id][5] = true
  redraw(id)
  return true
end

--disable: Disables a single button.
function disable(id)
  if button[id] == nil then
    return false
  end
  local colourBuffer = button[id][6]
  local textBuffer = button[id][0]
  local activeOrNot = button[id][8]
  button[id][8] = false
  button[id][6] = colors.black
  button[id][0] = ""
  redraw(id)
  button[id][6] = colourBuffer
  button[id][0] = textBuffer
  button[id][8] = activeOrNot
  button[id][5] = false
  return true
end

--getEnabled: Gets the enabled-state  of
--a button.
function getEnabled(id)
  if button[id] == nil then
    return -1
  end
  return button[id][5]
end

--setNotActiveColour: Changes the color
--when the button is not active.
function setNotActiveColour(id, colour)
  if button[id] == nil then
    return false
  end
  button[id][6] = colour
  if button[id][8] == false then
    redraw(id)
  end
  return true
end

--getNotActiveColour: Returns the
--color of the button when it's not active.
function getNotActiveColour(id)
  if button[id] == nil then
    return -1
  end
  return button[id][6]
end

--setActiveColour: Changes the color
--when the button is active
function setActiveColour(id, colour)
  if button[id] == nil then
    return false
  end
  button[id][7] = colour
  if button[id][8] == true then
    redraw(id)
  end
  return true
end

--getActiveColour: Returns the
--color of the button when it's active.
function getActiveColour(id)
  if button[id] == nil then
    return -1
  end
  return button[id][7]
end

--changeCurrentColour: Changes the color
--of the button!
function changeCurrentColour(id, colour)
  if button[id] == nil then
    return false
  end
  if button[id][8] == false then
    button[id][6] = colour
  else
    button[id][7] = colour
  end
  redraw(id)
  return true
end

--getCurrentColour: Returns the current
--color of the button.
function getCurrentColour(id)
  if button[id] == nil then
    return -1
  end
  if button[id][8] == false then
    return button[id][6]
  else
    return button[id][7]
  end
end

--switch: Switches the state of the button.
function switch(id)
  if button[id] == nil then
    return false
  end
  --Switch colors of the button
  button[id][8] = not button[id][8]
  redraw(id)
  return true
end

--setActive: Sets the button state to active.
function setActive(id)
  if button[id] == nil then
    return false
  end
  button[id][8] = true
  redraw(id)
  return true
end

--setNotActive: Sets the button state to not active.
function setNotActive(id)
  if button[id] == nil then
    return false
  end
  button[id][8] = false
  redraw(id)
return true
end

--isActive: Returns if the button is active
function isActive(id)
  if button[id] == nil then
    return -1
  end
  return button[id][8]
end