Extreme_Snake

local filename = 'extreme_snake_highscore.dat'

if not fs.exists(filename) then
  local file = fs.open(filename,'w')
  file.write('0')
  file.close()
end
local file = fs.open(filename,'r')
local hscore = file.readLine()
if not tonumber(hscore) then
  hscore = 0
  local file = fs.open(filename,'w')
  file.write('0')
  file.close()
end

hscore = tonumber(hscore)

local length = {}
local fruit = {{13,6,false},{17,8,false}}
local paused = false
for num = 1,6 do
  table.insert(length,{(7-num)+6,6})
end
local speed = 1
local size = 6
local x, y = 12,6
local direction = 0

--Settings
local color = colors.lime
local color2 = colors.green
--

local timer = 0
local dead = false
local width, height = term.getSize()
local score = -100
term.setBackgroundColor(colors.gray)
term.setCursorPos(1,1)
term.clearLine()

local function pauseHandler()
  while true do
    local ev = {os.pullEvent('key')}
    if ev[2] == 28 then
      if paused then
        paused = false
      else
        paused = true
        term.setCursorPos((width/2)-4,height/2)
        term.setTextColor(colors.yellow)
        term.setBackgroundColor(colors.black)
        write('[PAUSED]')
      end
    end
  end
end

local function display()
  while true do
  repeat sleep(0.05) until paused == false
  term.setBackgroundColor(colors.black)
  for curheightc = 2,height do
    term.setCursorPos(1,curheightc)
    term.clearLine()
  end
  for i,v in pairs(fruit) do
    if v[3] then
      paintutils.drawPixel(v[1],v[2],colors.yellow)
    else
      paintutils.drawPixel(v[1],v[2],colors.red)
    end
  end
  for i,v in pairs(length) do
    if (i+1)%3 == 0 then
      paintutils.drawPixel(v[1],v[2],color2)
    else
      paintutils.drawPixel(v[1],v[2],color)
    end
  end
  end
end
local function lose()
  repeat sleep(0.05) until dead
end
local function update()
  while true do
    timer = timer + 1
    if timer%speed == 0 then
      if direction == 0 then
        x = x + 1
      elseif direction == 1 then
        y = y + 1
      elseif direction == 2 then
        x = x - 1
      elseif direction == 3 then
        y = y - 1
      end
    if length[size] then
      table.remove(length,size)
    end
    table.insert(length,1,{x,y})
    end
    repeat sleep(0.05) until paused == false
    for i,v in pairs(length) do
      if i ~= 1 then
        if v[1] == x and v[2] == y then
          dead = true
        end
      end
    end
    if x < 1 or x > width or y < 2 or y > height then
      dead = true
    end
    for i,v in pairs(fruit) do
      if v[1] == x and v[2] == y then
        table.remove(fruit,i)
        if v[3] then
          size = size + 5
          score = score + 500
        else
          size = size + 1
          score = score + 100
        end
        local special = math.random(1,5)
        if special == 1 then
          special = true
        else
          special = false
        end
        local xposn = math.random(2,width-1)
        local yposn = math.random(3,height-1)
        for i,v in pairs(fruit) do
          if xposn == v[1] then
            if xposn ~= 2 then
              xposn = xposn - 1
            else
              xposn = xposn + 1
            end
          end
          if yposn == v[2] then
            if yposn ~= 3 then
              yposn = yposn - 1
            else
              yposn = yposn + 1
            end
          end
        end
        table.insert(fruit,{xposn,yposn,special})
      end
    end
  end
end
local function scoreCount()
  while true do
    sleep(0.05)
    term.setTextColor(colors.cyan)
    term.setBackgroundColor(colors.gray)
    term.setCursorPos(width-#('SCORE: '..score),1)
    write('SCORE: '..score)
    term.setCursorPos(2,1)
    write('LENGTH: '..#length)
    term.setCursorPos(20,1)
    write('HIGHSCORE: '..hscore)
  end
end
local function control()
  while true do
    sleep(0.01)
    local ev = {os.pullEvent('key')}
    local num = 0
    if ev[2] == keys.right and direction ~= 2 then
      direction = 0
    elseif ev[2] == keys.down and direction ~= 3 then
      direction = 1
    elseif ev[2] == keys.left and direction ~= 0 then
      direction = 2
    elseif ev[2] == keys.up and direction ~= 1 then
      direction = 3
    end
  end
end

parallel.waitForAny(pauseHandler,lose,display,update,control,scoreCount)
term.setBackgroundColor(colors.black)

if score > hscore then
    term.setCursorPos((width/2)-7,height/2)
    term.setTextColor(colors.yellow)
    print('[New highscore!]')
    local file = fs.open(filename,'w')
    file.writeLine(score)
    file.close()
    sleep(0.2)
    os.pullEvent('key')
else
    term.setCursorPos((width/2)-4,height/2)
    term.setTextColor(colors.red)
    print('[You died!]')
    sleep(0.2)
    os.pullEvent('key')
end

term.setCursorPos(1,1)
term.clear()