-- j2b2's Starpost Warp

local CV_SWMode = {
  ["Off"] = 0,
  ["All"] = 1,
  ["Checkpoint"] = 2,
  ["Finished"] = 3
}

local cvSWMode = CV_RegisterVar({name="swarp_mode",defaultvalue="Finished",flags=CV_NETVAR | CV_SHOWMODIF,PossibleValue=CV_SWMode})

local function IsValid(a)
  if a ~= nil then return a.valid end
	return false
end

local function CanWarp(player)
  return cvSWMode.value ~= 0 and (player.pflags & PF_FINISHED or cvSWMode.value < 3) and player.playerstate & PST_DEAD == 0 and player.spectator == false and player.exiting == 0
end

local function CheckpointValid(player,checkpoint)
  return checkpoint ~= nil and checkpoint.valid and (player.starpostnum >= checkpoint.health or cvSWMode.value ~= 2)
end

local function GetStarposts()
  local starposts = {}
  for mobj in mobjs.iterate() do
    if mobj.type == MT_STARPOST then
      table.insert(starposts,mobj)
    end
  end
  table.sort(starposts,function(a,b) return a.health < b.health end)
  return starposts
end

local function GetNextStarpost(player,starposts)
  if CheckpointValid(player,player.starpostlast) == false then
    if CheckpointValid(player,starposts[1]) then
      return 1, starposts[1]
    else
      return nil
    end
  end
  for i,v in ipairs(starposts) do
    if v == player.starpostlast then
      local nextStarpost = starposts[i+1]
      if CheckpointValid(player,nextStarpost) then
        return i+1, nextStarpost
      elseif CheckpointValid(player,starposts[1]) then
        return 1, starposts[1]
      else
        return
      end
    end
  end
end

local function GetPrevStarpost(player,starposts)
  local heighestStarpostNum = 0
  local heighestStarpost
  for i,v in ipairs(starposts) do
    if v == player.starpostlast and i > 1 and CheckpointValid(player,starposts[i-1]) then
      return i-1, starposts[i-1]
    elseif CheckpointValid(player,v) then
      heighestStarpostNum = i
      heighestStarpost = v
    end
  end
  return heighestStarpostNum, heighestStarpost
end

local function WarpToStarpost(player,starpost,starpostNumber)
  player.powers[pw_flashing] = 2*TICRATE
  player.powers[pw_carry] = CR_NONE
  player.pflags = player.pflags & ~(PF_JUMPED | PF_SPINNING | PF_STARTDASH | PF_THOKKED | PF_SHIELDABILITY | PF_GLIDING | PF_BOUNCING | PF_SLIDING)
  player.mo.momx = 0
  player.mo.momy = 0
  player.mo.momz = 0
  player.mo.angle = starpost.angle
  player.drawangle = starpost.angle
  player.mo.state = S_PLAY_STND
  player.mo.flags2 = player.mo.flags2 & ~MF2_TWOD
  if starpost.flags2 & MF2_OBJECTFLIP then
    player.mo.flags2 = player.mo.flags2 | MF2_OBJECTFLIP
    P_TeleportMove(player.mo,starpost.x,starpost.y,starpost.z+starpost.height)
  else
    player.mo.flags2 = player.mo.flags2 & ~MF2_OBJECTFLIP
    P_TeleportMove(player.mo,starpost.x,starpost.y,starpost.z)
  end
  S_StartSound(player.mo,sfx_mixup)
  if player == displayplayer then
    print("Warping to checkpoint #"..starpostNumber)
  end
end

addHook("TouchSpecial",function(mobj,toucher)
  if IsValid(toucher) then
    local shouldOverride = false
    if toucher.type == MT_PLAYER and CanWarp(toucher.player) and toucher.player.starpostlast ~= mobj and mobj.health <= toucher.player.starpostnum then
      toucher.player.starpostx = toucher.player.mo.x/FRACUNIT
      toucher.player.starposty = toucher.player.mo.y/FRACUNIT
      if mobj.flags2 & MF2_OBJECTFLIP then
        toucher.player.starpostz = mobj.z/FRACUNIT+mobj.height/FRACUNIT
        toucher.player.starpostscale = -toucher.player.mo.scale
      else
        toucher.player.starpostz = mobj.z/FRACUNIT
        toucher.player.starpostscale = toucher.player.mo.scale
      end
      toucher.player.starposttime = leveltime
      toucher.player.starpostangle = mobj.angle
      mobj.state = mobj.info.painstate
      S_StartSound(mobj,mobj.info.painsound)
      shouldOverride = true
    end
    toucher.player.starpostlast = mobj
    return shouldOverride
  end
end,MT_STARPOST)

addHook("PlayerThink",function(player)
  if CanWarp(player) then
    if player.cmd.buttons & BT_WEAPONNEXT and player.warping == false then
      local starposts = GetStarposts()
      local starpostNumber, starpost = GetNextStarpost(player,starposts)
      if starpost ~= nil then
        WarpToStarpost(player,starpost,starpostNumber)
      end
    elseif player.cmd.buttons & BT_WEAPONPREV and player.warping == false then
      local starposts = GetStarposts()
      local starpostNumber, starpost = GetPrevStarpost(player,starposts)
      if starpost ~= nil then
        WarpToStarpost(player,starpost,starpostNumber)
      end
    end
  end
  player.warping = player.cmd.buttons & (BT_WEAPONNEXT | BT_WEAPONPREV) > 0
end)

local HUD_X = 16
local HUD_Y = 76
local hudDelay = 0

hud.add(function(v)
  if CanWarp(displayplayer) and displayplayer.pflags & PF_FINISHED then
    if hudDelay > 0 then
      v.drawString(HUD_X,HUD_Y,"prev/next weapon:", V_SNAPTOTOP | V_SNAPTOLEFT | V_YELLOWMAP | V_HUDTRANS, "thin")
      v.drawString(HUD_X,HUD_Y+8,"warp to checkpoints", V_SNAPTOTOP | V_SNAPTOLEFT | V_HUDTRANS, "thin")
    else
      hudDelay = hudDelay + 1
    end
  else
    hudDelay = 0
  end
end,"game")

-- j2b2's Starpost Warp