--basic helper functions

if fs.exists("GoldSlideDir") == false then
  fs.makeDir("GoldSlideDir")
end

function clear(display)
  if display == nil then
    term.clear()
    term.setCursorPos(1,1)
  else
    screen = {}
    screen = display
    screen.clear()
    screen.setCursorPos(1,1)
  end
end

color = {
1,
2,
8,
16,
256,
2048,
4096,
8192,
32768,
16384
}


--click areas
menuBarBack = {
{2,3,4,5,6,7},
{1}
}

menuBarAdd = {
{9,10,11,12,13},
{1}
}

menuBarBGColor = {
{15,16,17,18,19,20,21,22,23,24},
{1}
}

menuBarNewSlide = {
{26,27,28,29,30,31,32,33,34,35,36},
{1}
}

boxChangeWidth = {
{51},
{1}
}

boxChangeHeight = {
{51},
{2}
}

boxDelete = {
{51},
{3}
}

addBarBox = {
{2,3,4,5,6,7,8},
{2}
}

addBarText = {
{10,11,12,13,14,15,16,17},
{2}
}

menuNew = {
{10,11,12,13,14,15,16,17,18,19,20,21,22},
{13,14,15}
}

menuOpen = {
{10,11,12,13,14,15,16,17,18,19,20,21,22,23},
{17,18,19}
}

menuDelete = {
{25,26,27,28,29,30,31,33,34,35,36,37,38,39,40},
{13,14,15}
}

menuShow = {
{25,26,27,28,29,30,31,32,33,34,35,36,37,38},
{17,18,19}
}

function checkClickArea(x,y,a)
  area = {}
  area = a

  xFound = false
  yFound = false

  for i,v in ipairs(area[1]) do
    if v == x then
      xFound = true
    end
  end

  for i,v in ipairs(area[2]) do
    if v == y then
      yFound = true
    end
  end

  if xFound and yFound then
    return true
  else
    return false
  end
end

function split(str, pattern)
  local t = { }
  local fpat = "(.-)" .. pattern
  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 aPrint(x,y,text,display)
  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  nText = split(text, "/n")

  y = y - 1

  for i,v in ipairs(nText) do
    screen.setCursorPos(x, y + i)
    screen.write(v)
  end
end

--element functions

function drawBox(x,y,w,h,color,display)

  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  screen.setBackgroundColor(color)
  i = 0
  while i < w do
    i2 = 0
    while i2 < h do
      screen.setCursorPos(x + i, y + i2)
      screen.write(" ")
      i2 = i2 + 1
    end
    i = i + 1
  end

  screen.setBackgroundColor(colors.black)
end

function findClickArea(x,y,w,h)
  xs = {}
  ys = {}

  i = 0
  while i < w do
    table.insert(xs, x + i)
    i = i + 1
  end

  i = 0
  while i < h do
    table.insert(ys, y + i)
    i = i + 1
  end

  return {xs, ys}
end

function drawText(x,y,text, bColor, tColor, display)
  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  screen.setBackgroundColor(bColor)
  screen.setTextColor(tColor)

  aPrint(x,y,text,screen)
  screen.setBackgroundColor(colors.black)
  screen.setTextColor(colors.white)
end

function findClickAreaTextBox(x,y,text)
  ys = {y}
  xs = {}

  maxLen = 0

  i = 0
  while i < string.len(text) do
    table.insert(xs, x + i)
    i = i + 1
  end

  return {xs, ys}
end

function textClickArea(x,y,element)
  text = element[4][1]
  xPos = element[2][1]
  yPos = element[2][2] - 1

  array = {}

  nText = split(text, "/n")

  found = false

  for i,v in ipairs(nText) do
    table.insert(array, findClickAreaTextBox(xPos,yPos + i,v))
  end

  for i,v in ipairs(array) do
    if checkClickArea(x,y,v) then
      found = true
    end
  end

  return found
end

--Drawing functions
function drawMenuBar(display)
  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  screen.setBackgroundColor(colors.yellow)
  screen.setTextColor(colors.black)
  screen.setCursorPos(1,1)
  screen.write("| Back | Add | BG Color | New Slide |")
  screen.setTextColor(colors.white)
  screen.setBackgroundColor(colors.black)
end

function drawColorPicker(display)

  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  for i,v in ipairs(color) do
    screen.setCursorPos(50,i)
    screen.setBackgroundColor(v)
    screen.write(".")
  end
end

function drawElementButtons(element, picker, display)
  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  screen.setBackgroundColor(colors.yellow)
  screen.setCursorPos(51,1)
  screen.write("X")
  if element == "box" then
    screen.setCursorPos(51,2)
    screen.write("C")
  elseif element == "textBox" then
    screen.setCursorPos(51,2)
    screen.setBackgroundColor(colors.yellow)
    screen.write("C")
    screen.setCursorPos(51,3)
    screen.write("T")
  end
  screen.setTextColor(colors.white)
  screen.setBackgroundColor(colors.black)
end

function drawFrame(num,element, display)
  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  drawMenuBar(screen)
  if element ~= nil then
    drawElementButtons(element, screen)
  end
  screen.setCursorPos(1,19)
  screen.write(num)
end

function drawAddType(display)
  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  screen.setCursorPos(1,2)
  screen.write("|  Box  |  Text  |")
end

--draw main menu
function drawMain()
  term.setBackgroundColor(colors.blue)
  clear()
  --"G"
  drawBox(15,3,7,1,colors.yellow)
  drawBox(15,4,1,7,colors.yellow)
  drawBox(15,11,10,1,colors.yellow)
  drawBox(25,8,1,4,colors.yellow)
  drawBox(20,8,6,1,colors.yellow)
  --"S"
  drawBox(27,3,7,1,colors.yellow)
  drawBox(27,4,1,3,colors.yellow)
  drawBox(27,7,7,1,colors.yellow)
  drawBox(33,8,1,4,colors.yellow)
  drawBox(27,11,7,1,colors.yellow)
  --"New Project"
  drawBox(10,13,13,3,colors.red)
  term.setBackgroundColor(colors.red)
  term.setTextColor(colors.black)
  term.setCursorPos(11,14)
  term.write("New Project")
  --"Open Project"
  drawBox(10,17,14,3,colors.red)
  term.setBackgroundColor(colors.red)
  term.setTextColor(colors.black)
  term.setCursorPos(11,18)
  term.write("Open Project")
  --"Delete Project"
  drawBox(25,13,16,3,colors.red)
  term.setBackgroundColor(colors.red)
  term.setTextColor(colors.black)
  term.setCursorPos(26,14)
  term.write("Delete Project")
  --"Show Project"
  drawBox(25,17,14,3,colors.red)
  term.setBackgroundColor(colors.red)
  term.setTextColor(colors.black)
  term.setCursorPos(26,18)
  term.write("Show Project")
end

--draw slide functions

function drawSlideInitial(project, slide, display)
  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  allElementsOnScreen = {}

  clear(screen)

  slideFolder = "GoldSlideDir/"..project.."/slide-"..slide.."/"

  shell.run(slideFolder.."id")
  shell.run(slideFolder.."bgcolor")

  screen.setBackgroundColor(bgColor)
  clear(screen)

  elementsFolder = slideFolder.."elements/"

  allElements = fs.list(elementsFolder)

  for i,v in ipairs(allElements) do
    if v == ".DS_Store" then
      table.remove(allElements, i)
    end
  end

  for i,v in ipairs(allElements) do

    file = fs.open(elementsFolder..v.."/element", "r")
    nElement = file.readAll()
    file.close()

    file = fs.open(elementsFolder..v.."/pos","r")
    nPos = file.readAll()
    file.close()
    nPos = textutils.unserialize(nPos)


    file = fs.open(elementsFolder..v.."/params","r") --sets param variable
    nParams = file.readAll()
    file.close()
    print(nParams)
    nParams = textutils.unserialize(nParams)

    area = {}

    --element config
    --{element, pos, area, params}

    --handling the type of element

    if nElement == "box" then
      drawBox(nPos[1],nPos[2],nParams[1],nParams[2],nParams[3],screen)
      area = findClickArea(nPos[1],nPos[2],nParams[1],nParams[2])
      table.insert(allElementsOnScreen, {nElement, nPos, area, nParams})
    elseif nElement == "textBox" then
      drawText(nPos[1],nPos[2],nParams[1],nParams[2],nParams[3],screen)
      area = findClickAreaTextBox(nPos[1], nPos[2], nParams[1])
      table.insert(allElementsOnScreen, {nElement, nPos, area, nParams})
    elseif nElement == "picture" then
      picture = paintutils.loadImage(elementsFolder..v.."/"..params[1])
      paintutils.drawImage(picture, pos[1], pos[2])
    end
  end
  return allElementsOnScreen
end

function drawSlide(elem, project, slide, display)
  if display == nil then
    screen = term
  else
    screen = {}
    screen = display
  end

  elements = {}
  elements = elem

  clear(screen)

  slideFolder = "GoldSlideDir/"..project.."/slide-"..slide.."/"

  shell.run(slideFolder.."id")
  shell.run(slideFolder.."bgcolor")

  screen.setBackgroundColor(bgColor)
  clear(screen)

  elementsFolder = slideFolder.."elements/"

  for i,v in ipairs(elements) do
    element = elements[i][1] --sets element variable
    pos = elements[i][2] --sets pos variable
    params = elements[i][4] --sets param variable


    --element config
    --{element, pos, area, params}

    --handling the type of element

    if element == "box" then
      drawBox(pos[1],pos[2],params[1],params[2],params[3], screen)
    elseif element == "textBox" then
      drawText(pos[1],pos[2],params[1],params[2],params[3], screen)
    elseif element == "picture" then
      picture = paintutils.loadImage(elementsFolder..v.."/"..params[1])
      paintutils.drawImage(picture, pos[1], pos[2])
    end

  end
end

--save function
function save(elem, project, slide)
  elements = {}
  elements = elem

  elementsFolder = "GoldSlideDir/"..project.."/slide-"..slide.."/elements/"

  allElements = fs.list(elementsFolder)

  for i,v in ipairs(allElements) do
    fs.delete(elementsFolder..v)
  end

  for i,v in ipairs(elements) do
    fs.makeDir(elementsFolder.."element-"..i)


    file = fs.open(elementsFolder.."element-"..i.."/element", "w")
    file.write(v[1])
    file.close()

    file = fs.open(elementsFolder.."element-"..i.."/pos", "w")
    file.write('{'..v[2][1]..','..v[2][2]..'}')
    file.close()

    if v[1] == "box" then
      file = fs.open(elementsFolder.."element-"..i.."/params", "w")
      file.write('{')
      file.write(v[4][1]..",")
      file.write(v[4][2]..",")
      file.write(v[4][3])
      file.write("}")
      file.close()
    elseif v[1] == "textBox" then
      file = fs.open(elementsFolder.."element-"..i.."/params", "w")
      file.write('{"')
      file.write(v[4][1]..'",')
      file.write(v[4][2]..",")
      file.write(v[4][3])
      file.write("}")
      file.close()
    end

  end
end

--create new
function createNewSlide(projectName,nSlideNum)
  path = "GoldSlideDir/"..projectName.."/slide-"..nSlideNum.."/"

  file = fs.open(path.."id", "w")
  file.write("slideId = "..nSlideNum)
  file.close()

  file = fs.open(path.."bgcolor", "w")
  file.write("bgColor = colors.black")
  file.close()

  path = path.."elements/element-0/"

  file = fs.open(path.."element", "w")
  file.close()

  file = fs.open(path.."pos", "w")
  file.close()

  file = fs.open(path.."params", "w")
  file.close()
end

function newProject(name)
  fs.makeDir("GoldSlideDir/"..name.."/")
  createNewSlide(name, 1)
end

--flow control

project = "project-1"


function editSlide(projectName)
  allSlides = fs.list("GoldSlideDir/"..projectName)

  for i,v in ipairs(allSlides) do
    if v == ".DS_Store" then
      table.remove(allSlides, i)
    end
  end

  clickID = 0
  elements = drawSlideInitial(projectName,1)

  slideCur = 1
  slideMin = 1
  slideMax = table.getn(allSlides)

  while true do
    allSlides = fs.list("GoldSlideDir/"..projectName)

    for i,v in ipairs(allSlides) do
      if v == ".DS_Store" then
        table.remove(allSlides, i)
      end
    end

    slideMax = table.getn(allSlides)

    drawSlide(elements, projectName, slideCur, screen)

    if clickID ~= 0 then
      drawFrame(slideCur, elements[clickID][1], screen)
    else
      drawFrame(slideCur,screen)
    end

    e,p1,p2,p3 = os.pullEvent()

    save(elements, projectName, slideCur)

    if e == "mouse_click" and p1 == 1 or p1 == 2 then

      drag = false

      for i = #elements,1,-1 do
        if elements[i][1] == "textBox" and textClickArea(p2,p3,elements[i]) then
          clickID = i
          newClick = true
        elseif elements[i][1] ~= "textBox" and checkClickArea(p2,p3,elements[i][3]) then
          clickID = i
          newClick = true
          areaX = elements[i][3][1]
          areaY = elements[i][3][2]

          if p2 == areaX[#areaX] and p3 == areaY[#areaY] and elements[i][1] == "box" then
            drag = true
          end
          break
        end
      end

      if p1 == 2 and clickID ~= 0 and elements[clickID][1] == "textBox" then
        term.setCursorBlink(true)
        newLine = false
        while true do
          text = elements[clickID][4][1]
          y = elements[clickID][2][2]
          x = elements[clickID][2][1]
          lines = split(text, "/n")
          nLines = #lines - 1
          if lines[#lines] == nil then
            xDis = 0
          else
            xDis = string.len(lines[#lines])
          end


          if newLine then
            term.setCursorPos(x, nLines + y + 1)
          else
            term.setCursorPos(x + xDis, nLines + y)
          end
          event, param1, param2, param3 = os.pullEvent()

          if event == "char" then
            text = text..param1
            elements[clickID][4][1] = text
            newLine = false
          elseif event == "key" then
            if param1 == 28 then
              text = text.."/n"
              term.setCursorPos(x, nLines + y + 1)
              elements[clickID][4][1] = text
              newLine = true
            elseif param1 == 14 then
              if string.sub(text,-2) == "/n" then
                temp = string.reverse(text)
                temp = string.sub(temp, 3)
                temp = string.reverse(temp)
              else
                temp = string.reverse(text)
                temp = string.sub(temp, 2)
                temp = string.reverse(temp)
              end

              text = temp
              elements[clickID][4][1] = text
            end
          elseif event == "mouse_click" then
            term.setCursorBlink(false)
            break
          end

          drawSlide(elements, projectName, slideCur)
          drawFrame(slideCur)
        end

      elseif newClick then
        newClick = false
      elseif p1 == 1 and clickID ~= 0 and p2 == 51 and p3 == 1 then
        table.remove(elements, clickID)
        clickID = 0
      elseif p1 ==1 and clickID ~= 0 and p2 == 51 and p3 == 2 then
        drawColorPicker()
        event, param1, param2, param3 = os.pullEvent()
        if event == "mouse_click" and param1 == 1 and param2 == 50 and param3 <= table.getn(color) then
          if elements[clickID][1] == "box" then
            elements[clickID][4][3] = color[param3]
          elseif elements[clickID][1] == "textBox" then
            elements[clickID][4][2] = color[param3]
          end
        end
      elseif p1 == 1 and clickID ~= 0 and p2 == 51 and p3 == 3 and elements[clickID][1] == "textBox" then
        drawColorPicker()
        event, param1, param2, param3 = os.pullEvent()
        if event == "mouse_click" and param1 == 1 and param2 == 50 and param3 <= table.getn(color) then
          if elements[clickID][1] == "textBox" then
            elements[clickID][4][3] = color[param3]
          end
        end
      elseif checkClickArea(p2,p3,menuBarAdd) then
        drawAddType()

        e1, p11, p21, p31 = os.pullEvent()

        if e1 == "mouse_click" and p11 == 1 then
          if checkClickArea(p21, p31, addBarBox) then
            table.insert(elements, {"box" , {4,4} , findClickArea(4,4,2,2), {2,2,colors.orange}})
          elseif checkClickArea(p21,p31, addBarText) then
            table.insert(elements, {"textBox", {4,4}, findClickAreaTextBox(4,4,"text"), {"text", colors.white, colors.black}})
          end
        end
      elseif checkClickArea(p2,p3,menuBarBack) then
        clear()
        break
      elseif checkClickArea(p2,p3,menuBarBGColor) then
        drawColorPicker()
        event, param1, param2, param3 = os.pullEvent()
        if event == "mouse_click" and param1 == 1 and param2 == 50 and param3 <= table.getn(color) then
          term.setBackgroundColor(colors.blue)
          file = fs.open("GoldSlideDir/"..projectName.."/slide-"..slideCur.."/bgcolor", "w")
          file.write("bgColor = "..color[param3])
          file.close()
        end
      elseif checkClickArea(p2,p3,menuBarNewSlide) then
        createNewSlide(projectName, #allSlides + 1)
        slideCur = #allSlides + 1
      else
        if clickID ~= 0 then
          clickID = 0
        end
      end
    elseif e == "mouse_drag" and p1 == 1 then
      if clickID ~= 0 and drag == false then
        elements[clickID][2][1] = p2
        elements[clickID][2][2] = p3

        e = elements[clickID]

        if e[1] == "box" then
          elements[clickID][3] = findClickArea(e[2][1], e[2][2], e[4][1], e[4][2])
        elseif e[1] == "textBox" then
          elements[clickID][3] = findClickAreaTextBox(e[2][1], e[2][2], e[4][1])
        end
      elseif clickID ~= 0 and drag == true then
        area = elements[clickID][3]
        params = elements[clickID][4]

        xDis = p2 - area[1][#area[1]]
        yDis = p3 - area[2][#area[2]]

        elements[clickID][4][1] = math.abs(params[1] + xDis)
        elements[clickID][4][2] = math.abs(params[2] + yDis)

        w = elements[clickID][4][1]
        h = elements[clickID][4][2]
        position = elements[clickID][2]

        elements[clickID][3] = findClickArea(position[1], position[2], w, h)
      end
    elseif e == "key" then
      if p1 == 205 then
        if slideCur < #allSlides then
          slideCur = slideCur + 1
        end
      elseif p1 == 203 then
        if slideCur > 1 then
          slideCur = slideCur - 1
        end
      end
      clickID = 0

      elements = drawSlideInitial(projectName, slideCur)
    end
  end
end

function drawProjects(allProjects)
  tab = {}
  tab = allProjects

  if tab[1] ~= nil then

    term.setBackgroundColor(colors.blue)
    term.setTextColor(colors.black)
    clear()
    print("Select an Option")

    x = 3
    y = 3

    areas = {}
    projects = {}

    for i,v in ipairs(tab) do
      if v == ".DS_Store" then
        table.remove(tab, i)
      end
    end

    for i,v in ipairs(tab) do
      if x + string.len(v) + 2 > 49 then
        x = 3
        y = y + 4
      end

      drawBox(x,y,string.len(v) + 2, 3, colors.red)
      term.setCursorPos(x + 1, y + 1)
      term.setBackgroundColor(colors.red)
      term.setTextColor(colors.white)
      term.write(v)

      table.insert(areas, findClickArea(x,y,string.len(v) + 2, 3))

      if x > 49 then
        x = 3
        y = y + 4
      else
        x = x + string.len(v) + 3
      end

    end

    for i,v in ipairs(tab) do
      table.insert(projects, {v, areas[i]})
    end

    return projects
  else

    return "NOPE"

  end
end

function findMonitors()
  mons = {}

  for i,v in ipairs(rs.getSides()) do
    if peripheral.getType(v) == "monitor" then
      table.insert(mons, v)
    end
  end

  return mons
end

function slideShow(project, display)
  screen1 = {}
  screen2 = {}
  screen1 = display
  screen2 = term

  slideCur = 1

  allSlides = fs.list("GoldSlideDir/"..project.."/")
  for i,v in ipairs(allSlides) do
    if v == ".DS_Store" then
      table.remove(allSlides, i)
    end
  end

  slideMin = 1
  slideMax = #allSlides

  elements = drawSlideInitial(project, slideCur, screen1)
  elements = drawSlideInitial(project, slideCur, screen2)

  screen.setCursorBlink(false)

  while true do
    clear()

    drawSlide(elements, project, slideCur, screen1)
    drawSlide(elements, project, slideCur, screen2)

    e,p1 = os.pullEvent()

    if e == "key" then
      if p1 == 203 then
        if slideCur > 1 then
          slideCur = slideCur - 1
        end
      elseif p1 == 205 then
        if slideCur < slideMax then
          slideCur = slideCur + 1
        end
      elseif p1 == 14 then
        break
      end
    end

    elements = drawSlideInitial(project, slideCur, screen1)
    elements = drawSlideInitial(project, slideCur, screen2)
  end
end



while true do
  drawMain()
  term.setCursorPos(51,1)
  term.setBackgroundColor(colors.red)
  term.setTextColor(colors.white)
  term.write("X")
  term.setCursorPos(51,2)
  term.setBackgroundColor(colors.yellow)
  term.write("i")

  event, parameter1, parameter2, parameter3 = os.pullEvent()
  term.setBackgroundColor(colors.black)
  if event == "mouse_click" and parameter1 == 1 then
    if checkClickArea(parameter2, parameter3, menuNew) then
      term.setBackgroundColor(colors.black)
      clear()
      print("This part will be better later, I just wanted to add something here temporarily")
      term.write("Enter project name: ")
      name = read()
      newProject(name)
    elseif checkClickArea(parameter2, parameter3, menuOpen) then
      allProjects = fs.list("GoldSlideDir/")
      objects = drawProjects(allProjects)

      if objects ~= "NOPE" then
        e, p1, p2, p3 = os.pullEvent()
        if e == "mouse_click" and p1 == 1 then
          for i,v in ipairs(objects) do
            if checkClickArea(p2,p3,v[2]) then
              editSlide(v[1])
            end
          end
        end
      end
    elseif checkClickArea(parameter2, parameter3, menuShow) then
      allProjects = fs.list("GoldSlideDir/")
      objects = drawProjects(allProjects)

      if objects ~= "NOPE" then
        e, p1, p2, p3 = os.pullEvent()
        if e == "mouse_click" and p1 == 1 then
          for i,v in ipairs(objects) do
            if checkClickArea(p2,p3,v[2]) then
              peripherals = findMonitors()
              objects2 = drawProjects(peripherals)

              term.setBackgroundColor(colors.black)
              if objects2 ~= "NOPE" then
                e2, param1, param2, param3 = os.pullEvent()
                if e2 == "mouse_click" and param1 == 1 then
                  for o,k in ipairs(objects2) do
                    if checkClickArea(param2,param3,k[2]) then
                      slideShow(v[1], peripheral.wrap(k[1]))
                    end
                  end
                end
              end
            end
          end
        end
      end
    elseif checkClickArea(parameter2, parameter3, menuDelete) then
      allProjects = fs.list("GoldSlideDir/")
      objects = drawProjects(allProjects)

      if objects ~= "NOPE" then
        e, p1, p2, p3 = os.pullEvent()
        if e == "mouse_click" and p1 == 1 then
          for i,v in ipairs(objects) do
            if checkClickArea(p2,p3,v[2]) then
              fs.delete("GoldSlideDir/"..v[1])
            end
          end
        end
      end
    elseif parameter2 == 51 and parameter3 == 1 then
      term.setBackgroundColor(colors.black)
      clear()
      break
    elseif parameter2 == 51 and parameter3 == 2 then
      term.setBackgroundColor(colors.blue)
      term.setTextColor(colors.black)
      clear()

      print("Thankyou for downloading GoldSlide!")
      print()
      print("To create a project, click new project. Then click open project and select the new project to edit it")
      print()
      print("Keyboard controls to present a slideshow")
      print("----------------------------------------")
      print("Left arrow key - back a slide")
      print()
      print("Right arrow key - forward a slide")
      print()
      print("Backspace - back to main menu")
      print()
      print()
      print()
      print("Press enter")
      read()

    end
  end
end