--Lets make a game.. No plagurizing or sharing this to any site other then Computercraft.info
local Version = 0.1
local Player = {"<", ">", "^", "V"}
local Laser = {}
local Lasers = {"-", "-", "i", "!"}
local Pulsing = {"o", "O", "0", "O"}
local PulseExplodes = {}
local Pulse = {}
local Cooldown = 0
local CooldownPulse = 0
local Map = {}
local MapView = {}
local Health = 10
local Lives = 3
local Score = 10
local Name = ""
function clear()
  term.clear()
  term.setCursorPos(1,1)
end

function LoadFile()
  repeat
    clear()
    term.setCursorPos(1,2)
    for n,files in ipairs(fs.list("Maps")) do
    print(files)
    end
    term.setCursorPos(1,1)
    write("A map file: ")
    Name = read()
    if not fs.exists("Maps/"..Name) then
      print("That file doesnt exist")
      sleep(3)
    end
  until fs.exists("Maps/"..Name)
  clear()
  File = io.open("Maps/"..Name, "r")
  for line in File:lines() do
    Map[#Map+1] = line.."\n"
  end
  PlayerCords = Map[1]
  PlayerDir = tonumber(string.sub(PlayerCords, 5, 5))
  PlayerX = tonumber(string.sub(PlayerCords, 1, 2))
  PlayerY = tonumber(string.sub(PlayerCords, 3, 4))
  table.remove(Map, 1)
  File:close()
  p = io.open("Debug", "w")
  for n=1,#Map do
    p:write(Map[n])
  end
  for n=1,#Map do
    MapView[n] = Map[n]
  end
  p:close()
  StatusBox()
  reDraw()
end

function Load()
  Name = ""
  LoadFile()
end

function Tick()
  if Cooldown > 0 then
    Cooldown = Cooldown-1
  end
  if CooldownPulse > 0 then
    CooldownPulse = CooldownPulse-1
  end
  PulseMove()
  LaserMove()
  CheckUnder()
  UpdateExplode()
  reDraw()
  Ticker = os.startTimer(0.1)
end

function CheckUnder() -- Check under the player
  if CheckMapView(PlayerX, PlayerY) ~= " " then
    if CheckMapView(PlayerX, PlayerY) == "x" then --Pickup pack!
      StatusBox("Health", 5)
      deleteMapView(PlayerX, PlayerY)
    elseif CheckMapView(PlayerX, PlayerY) == "o" then -- Hit by explosion!
      StatusBox("Health", -3)
      deleteMapView(PlayerX, PlayerY)
    elseif CheckMapView(PlayerX, PlayerY) == "i" or CheckMapView(PlayerX, PlayerY) == "!" or CheckMapView(PlayerX, PlayerY) == "-" then --Laser!
      StatusBox("Health", -5)
      deleteMapView(PlayerX, PlayerY)
      for n=1,#Laser do
        if Laser[n] then
          local LaserX = tonumber(string.sub(Laser[n], 1, 2))
          local LaserY = tonumber(string.sub(Laser[n], 3, 4))
          if LaserX == PlayerX and LaserY == PlayerY then
            table.remove(Laser, n)
            n = n-1
          end
        end
      end
    elseif checkPulse() then --pulse!
      StatusBox("Health", -10)
      deleteMapView(PlayerX, PlayerY)
      PulseExplode(checkPulse())
      for n=1,#Pulse do
        if Pulse[n] then
          local PulseX = tonumber(string.sub(Pulse[n], 1, 2))
          local PulseY = tonumber(string.sub(Pulse[n], 3, 4))
          if PulseX == PlayerX and PulseY == PlayerY then
            table.remove(Pulse, n)
            n = n-1
          end
        end
      end
    end
  end
end

function checkPulse()
  for n=1,#Pulse do
    if Pulse[n] then
      local PulseX = tonumber(string.sub(Pulse[n], 1, 2))
      local PulseY = tonumber(string.sub(Pulse[n], 3, 4))
      if PulseX == PlayerX and PulseY == PlayerY then
        return PulseX, PulseY
      end
    end
  end
  return false
end

function StatusBox(Type, Modifier)
  FlashHP = false
  FlashLives = false
  if Type == "Health" then
    Health = tonumber(Health)+tonumber(Modifier)
    FlashHP = true
    if Health <= 0 then
      if Lives > 1 then
        Lives = Lives-1
        Health = 10
        FlashLives = true
      else
        clear()
        print("You died")
        error()
      end
    end
  end
  DrawStatus()
end

function DrawStatus()
  for n=1,3 do
    MapView[n] = string.sub(MapView[n], 14, string.len(MapView[4]))
  end
  local ScoreNum = tonumber("4")-string.len(Score)
  local Spaces = string.rep(" ", ScoreNum)
  MapView[1] = "Score: "..Score..Spaces.." O"..MapView[1]
  if FlashLives == true then
    MapView[2] = "Lives:      O"..MapView[2]
  else
    MapView[2] = "Lives: "..Lives.."    O"..MapView[2]
  end
  local HealthNum = tonumber("4")-string.len(Health)
  local Spaces = string.rep(" ", HealthNum)
  if FlashHP == true then
    MapView[3] = "Health:     O"..MapView[3]
  else
    MapView[3] = "Health: "..Health..Spaces.."O"..MapView[3]
  end
  MapView[4] = string.sub(MapView[4], 14, string.len(MapView[4]))
  MapView[4] = "OOOOOOOOOOOOO"..MapView[4]
  Draw = os.startTimer(0.15)
end

function CreateLaser(x, y, dir)
  if CheckMapView(x, y) ~= "O" then
    Laser[#Laser+1] = Num(x)..Num(y)..dir
    EditMapView(x, y, Lasers[dir])
  end
  Cooldown = 5
end

function CreatePulse(x, y, dir)
  if CheckMapView(x, y) ~= "O" then
    Pulse[#Pulse+1] = Num(x)..Num(y)..dir.."1".."1"
    EditMapView(x, y, Pulsing[dir])
  end
  CooldownPulse = 30
end

function Num(num)
  if string.len(num) == 1 then
    return "0"..num
  else
    return num
  end
end

function LaserMove()
  for n=1,#Laser do
    if Laser[n] then
      local LaserX = tonumber(string.sub(Laser[n], 1, 2))
      local LaserY = tonumber(string.sub(Laser[n], 3, 4))
      local LaserDir = tonumber(string.sub(Laser[n], 5, 5))
      deleteMapView(LaserX, LaserY)
      if LaserDir == 1 then
        LaserX = LaserX-1
      elseif LaserDir == 2 then
        LaserX = LaserX+1
      elseif LaserDir == 3 then
        LaserY = LaserY-1
      elseif LaserDir == 4 then
        LaserY = LaserY+1
      else
        error("LaserDir errored")
      end
      if CheckMapView(LaserX, LaserY) == " " then
        EditMapView(LaserX, LaserY, Lasers[LaserDir])
        Laser[n] = Num(LaserX)..Num(LaserY)..LaserDir
      else
        table.remove(Laser, n)
        n = n-1
      end
    end
  end
end

function PulseMove()
  for n=1,#Pulse do
    if Pulse[n] then
      local PulseX = tonumber(string.sub(Pulse[n], 1, 2))
      local PulseY = tonumber(string.sub(Pulse[n], 3, 4))
      local PulseDir = tonumber(string.sub(Pulse[n], 5, 5))
      local PulseState = tonumber(string.sub(Pulse[n], 6, 6))
      local Speed = tonumber(string.sub(Pulse[n], 7, 7))
      deleteMapView(PulseX, PulseY)
      local Sparex = PulseX
      local Sparey = PulseY
      if Speed == 1 then
        if PulseDir == 1 then
          PulseX = PulseX-1
        elseif PulseDir == 2 then
          PulseX = PulseX+1
        elseif PulseDir == 3 then
          PulseY = PulseY-1
        elseif PulseDir == 4 then
          PulseY = PulseY+1
        else
          error("LaserDir errored")
        end
        Speed = 0
      else
        Speed = 1
      end
      if PulseState == 4 then
        PulseState = 1
      else
        PulseState = PulseState+1
      end
      if CheckMap(PulseX, PulseY) == " " then
        EditMapView(PulseX, PulseY, Pulsing[PulseState])
        Pulse[n] = Num(PulseX)..Num(PulseY)..PulseDir..PulseState..Speed
      else
        PulseExplode(Sparex, Sparey)
        table.remove(Pulse, n)
        n = n-1
      end
    end
  end
end

function PulseExplode(x, y, Spread)
  if not Spread then Spread = "3" end
  local Nope = 5
  for n=1,#PulseExplodes do
    if PulseExplodes[n] then
      local PulseX = tonumber(string.sub(PulseExplodes[n], 1, 2))
      local PulseY = tonumber(string.sub(PulseExplodes[n], 3, 4))
      if PulseX == x and PulseY == y then -- Matches another explosion. Dont make it! Abort abort!
        Nope = 4
      end
    end
  end
  if Nope == 5 then -- Nothing is here.. right?
    if CheckMapView(x, y) ~= "O" then
      PulseExplodes[#PulseExplodes+1] = Num(x)..Num(y).."3"..Spread
      EditMapView(x, y, "o")
    end
  end
end
fs.delete("Log")
function Logger(loggy)
  p = io.open("Log", "a")
  p:write(loggy.."\n")
  p:close()
end

function UpdateExplode()
  for n=1,#PulseExplodes do
    if PulseExplodes[n] then
      local PulseX = tonumber(string.sub(PulseExplodes[n], 1, 2))
      local PulseY = tonumber(string.sub(PulseExplodes[n], 3, 4))
      local PulseStatus = tonumber(string.sub(PulseExplodes[n], 5, 5))
      local Spread = tonumber(string.sub(PulseExplodes[n], 6, 6))
      if PulseStatus < 1 then -- How long it has left in the world
        deleteMapView(PulseX, PulseY)
        table.remove(PulseExplodes, n)
      elseif Spread ~= 0 then
        PulseExplode(PulseX+1, PulseY, Spread-1)
        PulseExplode(PulseX-1, PulseY, Spread-1)
        PulseExplode(PulseX, PulseY+1, Spread-1)
        PulseExplode(PulseX, PulseY-1, Spread-1)
      end
      if PulseExplodes[n] then
        if PulseStatus ~= 0 then
        PulseExplodes[n] = Num(PulseX)..Num(PulseY)..(PulseStatus-1)..(Spread-1)
      end
      end
    end
  end
end

function deleteMapView(x,y)
  local First = string.sub(MapView[y], 1, x-1)
  local Second = string.sub(MapView[y], x+1, string.len(MapView[y]))
  MapView[y] = First.." "..Second
end

function deleteMap(x,y)
  local First = string.sub(MapView[y], 1, x-1)
  local Second = string.sub(MapView[y], x+1, string.len(MapView[y]))
  MapView[y] = First.." "..Second
end

function Direction(xory, dir)
  if xory == "x" then
    if dir == 1 then --Left
      return -1
    elseif dir == 2 then --Right
      return 1
    elseif dir == 3 or dir == 4 then
      return 0
    else
      error("funtion Direction was handled incorrectly")
    end
  elseif xory == "y" then
    if dir == 3 then --Up
      return -1
    elseif dir == 4 then --Down
      return 1
    elseif dir == 1 or dir == 2 then
      return 0
    else
      error("funtion Direction was handled incorrectly")
    end
  else
    error("You need to use x or y!!!! in function direction!")
  end
end

function reDraw()
  clear()
  for n=1,#MapView do
    term.setCursorPos(1, n)
    term.write(MapView[n])
  end
  term.setCursorPos(PlayerX, PlayerY)
  term.write(Player[PlayerDir])
end

function CheckMap(x, y)
  if Map[y] then
    local MapString = Map[y]
    MapString = string.sub(MapString, x, x)
    return MapString
  else
    return "O"
  end
end

function CheckMapView(x, y)
  if MapView[y] then
    local Lens = string.len(MapView[y])
    if x > 0 and x < Lens then
      local MapString = MapView[y]
      MapString = string.sub(MapString, x, x)
      return MapString
    else
      return "O"
    end
  end
  return "O"
end

function EditMapView(x, y, Get)
  local First = string.sub(MapView[y], 1, x-1)
  local Second = string.sub(MapView[y], x+1, string.len(MapView[y]))
  MapView[y] = First..Get..Second
end

function EditMap(x, y, Get)
  local First = string.sub(Map[y], 1, x-1)
  local Second = string.sub(Map[y], x+1, string.len(Map[y]))
  Map[y] = First..Get..Second
end

function MovePlayer()
  Tick()
  while true do
    Events = {os.pullEvent()}
    if Events[1] == "key" then
      if Events[2] == 200 or Events[2] == 17 then -- Up
        PlayerDir = 3
        if CheckMapView(PlayerX, PlayerY+Direction("y", PlayerDir)) ~= "O" then
          PlayerY = PlayerY+Direction("y", PlayerDir)
          CheckUnder()
        end
        reDraw()
      elseif Events[2] == 208 or Events[2] == 31 then -- Down
        PlayerDir = 4
        if CheckMapView(PlayerX, PlayerY+Direction("y", PlayerDir)) ~= "O" then
          PlayerY = PlayerY+Direction("y", PlayerDir)
          CheckUnder()
        end
        reDraw()
      elseif Events[2] == 203 or Events[2] == 30 then -- Left
        PlayerDir = 1
        if CheckMapView(PlayerX+Direction("x", PlayerDir), PlayerY) ~= "O" then
          PlayerX = PlayerX+Direction("x", PlayerDir)
          CheckUnder()
        end
        reDraw()
      elseif Events[2] == 205 or Events[2] == 32 then -- Right
        PlayerDir = 2
        if CheckMapView(PlayerX+Direction("x", PlayerDir), PlayerY) ~= "O" then
          PlayerX = PlayerX+Direction("x", PlayerDir)
          CheckUnder()
        end
        reDraw()
      elseif Events[2] == 57 then --Spacebar
        if Cooldown == 0 then
          CreateLaser(PlayerX+Direction("x", PlayerDir), PlayerY+Direction("y", PlayerDir), PlayerDir)
        end
      elseif Events[2] == 45 then -- x button
        if CooldownPulse == 0 then
          CreatePulse(PlayerX+Direction("x", PlayerDir), PlayerY+Direction("y", PlayerDir), PlayerDir)
        end
      end
    elseif Events[1] == "timer" and Events[2] == Ticker then --Tick
      Tick()
    elseif Events[1] == "timer" and Events[2] == Draw then
      StatusBox("Nothing", "Ignore")
    end
  end
end
Load()
MovePlayer()