NewtonAI.lua

function widget:GetInfo()
   return {
      name         = "NewtonAI",
      desc         = "attempt to make AI for Newton. Version 1.00",
      author       = "terve886, parts by ivand/Shaman",
      date         = "2019",
      license      = "PD", -- should be compatible with Spring
      layer        = 11,
	  handler	   = true, --for adding customCommand into UI
      enabled      = false
   }
end

local sqrt = math.sqrt
local UPDATE_FRAME=10
local NewtonStack = {}
local GetUnitMaxRange = Spring.GetUnitMaxRange
local GetUnitPosition = Spring.GetUnitPosition
local GetMyAllyTeamID = Spring.GetMyAllyTeamID
local GiveOrderToUnit = Spring.GiveOrderToUnit
local GetUnitsInSphere = Spring.GetUnitsInSphere
local GetUnitAllyTeam = Spring.GetUnitAllyTeam
local GetUnitIsDead = Spring.GetUnitIsDead
local GetMyTeamID = Spring.GetMyTeamID
local GetUnitDefID = Spring.GetUnitDefID
local nearest = Spring.GetUnitNearestAlly
local target = Spring.SetUnitTarget
local GetUnitVelocity = Spring.GetUnitVelocity
local GetGroundHeight = Spring.GetGroundHeight
local GetTeamUnits = Spring.GetTeamUnits
local GetUnitHealth = Spring.GetUnitHealth
local GetUnitWeaponTarget  = Spring.GetUnitWeaponTarget 
local ENEMY_DETECT_BUFFER  = 60
local Echo = Spring.Echo
local Newton_NAME = "turretimpulse"
local Imp_NAME = "cloakbomb"
local Scuttle_NAME = "jumpbomb"
local Pyro_NAME = "jumpraid"
local Snitch_NAME = "shieldbomb"
local Puppy_NAME = "jumpscout"
local Limpet_NAME = "amphbomb"
local CMD_PUSH_PULL = 35666
local Pull = 0
local Push = 1
local GetSpecState = Spring.GetSpectatingState
local CMD_STOP = CMD.STOP
local CMD_ATTACK = CMD.ATTACK
local selectedNewtons = nil

local GRAVITY = -Game.gravity/30/30
local AIR_DENSITY = 1.2/4
local DRAG_COEFF = 1.0
local radius = UnitDefNames["turretimpulse"].radius

local CMD_TOGGLE_NewtonAI = 19991
local NewtonUnitDefID = UnitDefNames["turretimpulse"].id

local cmdToggleNewtonAI = {
	id      = CMD_TOGGLE_NewtonAI,
	type    = CMDTYPE.ICON,
	tooltip = 'Toggles NewtonAI widget behavior for unit.',
	action  = 'oneclickwep',
	params  = { }, 
	texture = 'LuaUI/Images/commands/states/ai_on.png',
	pos     = {CMD_ONOFF,CMD_REPEAT,CMD_MOVE_STATE,CMD_FIRE_STATE, CMD_RETREAT},  
}

local NewtonAI = {
	unitID,
	allyTeamID = GetMyAllyTeamID(),
	range,
	maxHealth,
	toggle = true,
	checkpoint = -1,
	
	
	new = function(self, unitID)
		--Echo("NewtonAI added:" .. unitID)
		self = deepcopy(self)
		self.unitID = unitID
		self.range = GetUnitMaxRange(self.unitID)
		self.maxHealth = UnitDefs[GetUnitDefID(self.unitID)].health
		return self
	end,

	unset = function(self)
		--Echo("NewtonAI removed:" .. self.unitID)
		GiveOrderToUnit(self.unitID,CMD_STOP, {}, {""},1)
		return nil
	end,
	
	getToggleState = function(self)
		return self.toggle
	end,
	
	toggleOn = function (self)
		Echo("NewtonAI toggled On")
		self.toggle = true
	end,
	
	toggleOff = function (self)
		Echo("NewtonAI toggled Off")
		self.toggle = false
	end,
	
	pushBombsAndHeavies = function (self)
		if (GetUnitHealth(self.unitID)<self.maxHealth*0.3)then
				GiveOrderToUnit(self.unitID,CMD_PUSH_PULL, {Push}, 0)
				return
			end
		local target = {GetUnitWeaponTarget(self.unitID, 1)}
		if(target[1]==1)then
			if not (GetUnitAllyTeam(target[3]) == self.allyTeamID) then
				DefID = GetUnitDefID(target[3])
				if not(DefID == nil)then
					if((UnitDefs[DefID].mass>380 and UnitDefs[DefID].isBuilding == false and UnitDefs[DefID].name~=Crab_NAME) or UnitDefs[DefID].name==Imp_NAME or UnitDefs[DefID].name==Scuttle_NAME or UnitDefs[DefID].name==Snitch_NAME or UnitDefs[DefID].name==Puppy_NAME or UnitDefs[DefID].name==Limpet_NAME) then
						GiveOrderToUnit(self.unitID,CMD_PUSH_PULL, {Push}, 0)
						return
					end
				end
			end
		end
	end,
	
	handle = function(self)
		if (GetUnitHealth(self.unitID)<self.maxHealth*0.33)then
				GiveOrderToUnit(self.unitID,CMD_PUSH_PULL, {Push}, 0)
				return
			end
		if (self.toggle) then
			self.checkpoint = self.checkpoint+1
			local target = {GetUnitWeaponTarget(self.unitID, 1)}
			if(target[1]==1)then
				if not(GetUnitAllyTeam(target[3]) == self.allyTeamID) then
					DefID = GetUnitDefID(target[3])
					if not(DefID == nil)then
						if (UnitDefs[DefID].isBuilding == false)then
							if (self.checkpoint == 5)then
								if (UnitDefs[DefID].isAirUnit==true)then
									GiveOrderToUnit(self.unitID,CMD_PUSH_PULL, {Pull}, 0)
									return
								else
									GiveOrderToUnit(self.unitID,CMD_PUSH_PULL, {Push}, 0)
								end
								return
							end
							if (self.checkpoint >= 10)then
								self.checkpoint = -1
								if(UnitDefs[DefID].mass>200 or UnitDefs[DefID].name==Imp_NAME or UnitDefs[DefID].name==Scuttle_NAME or UnitDefs[DefID].name==Snitch_NAME or UnitDefs[DefID].name==Pyro_NAME or UnitDefs[DefID].name==Puppy_NAME or UnitDefs[DefID].name==Limpet_NAME) then
									GiveOrderToUnit(self.unitID,CMD_PUSH_PULL, {Push}, 0)
								else
									GiveOrderToUnit(self.unitID,CMD_PUSH_PULL, {Pull}, 0)
								end
								return
							end

							if (UnitDefs[DefID].isAirUnit==true)then
								GiveOrderToUnit(self.unitID,CMD_PUSH_PULL, {Pull}, 0)
								return
							end
							
							if(UnitDefs[DefID].mass>200 or UnitDefs[DefID].name==Imp_NAME or UnitDefs[DefID].name==Scuttle_NAME or UnitDefs[DefID].name==Snitch_NAME or UnitDefs[DefID].name==Pyro_NAME or UnitDefs[DefID].name==Puppy_NAME or UnitDefs[DefID].name==Limpet_NAME) then
								GiveOrderToUnit(self.unitID,CMD_PUSH_PULL, {Push}, 0)
								return
							end
						end
					end
				end
			end
		else
			self:pushBombsAndHeavies()
		end
	end
}

local function GetDragAccelerationVec(vx, vy, vz, mass, radius)


    local sx = vx <= 0 and -1 or 1
    local sy = vy <= 0 and -1 or 1
    local sz = vz <= 0 and -1 or 1

    local dragScale = 0.5 * AIR_DENSITY * DRAG_COEFF * (math.pi * radius * radius * 0.01 * 0.01)

    return
        math.clamp((vx * vx * dragScale * -sx) / mass, -math.abs(vx), math.abs(vx)),
        math.clamp((vy * vy * dragScale * -sy) / mass, -math.abs(vy), math.abs(vy)),
        math.clamp((vz * vz * dragScale * -sz) / mass, -math.abs(vz), math.abs(vz));
end

function WillHitMe(unitID, unitRadius, targetID, targetMass, targetRadius, frames, distTolerance)
	DefID = GetUnitDefID(targetID)
	if(DefID and UnitDefs[DefID].isAirUnit==true)then
		return false
	end
	local tvx, tvy, tvz = GetUnitVelocity(targetID)
	if (tvx==nil)then
		return false
	end
	local _, _, _, umx, umy, umz  = GetUnitPosition(unitID, true) --mid pos
	local tx, ty, tz, tmx, tmy, tmz  = GetUnitPosition(targetID, true) --mid pos
	
	if (tmx==nil)then
		return false
	end
	local tox, toy, toz = tmx - tx, tmy - ty, tmz - tz --offsets

	for i = 1, frames do
		height = GetGroundHeight(tx, tz)
		if ty > height then
			tvy = tvy + GRAVITY
			local dx, dy, dz = GetDragAccelerationVec(tvx, tvy, tvz, targetMass, targetRadius)
			tvx, tvy, tvz = tvx + dx, tvy + dy, tvz + dz --drag will decrease velocity

			tx, ty, tz = tx + tvx, ty + tvy, tz + tvz

			if ty <= GetGroundHeight(tx, tz) then --crashed onto land
				tvy = 0
			end
		else
			tx, ty, tz = tx + tvx, height, tz + tvz
		end

		tmx, tmy, tmz = tx + tox, ty + toy, tz + toz --apply offsets

		local distance = sqrt( (umx - tmx)^2 + (umy - tmy)^2 + (umz - tmz)^2 ) - unitRadius - targetRadius

		if distance < distTolerance then
			return true
		end
	end
	return false
end

function widget:UnitFinished(unitID, unitDefID, unitTeam)
		if (UnitDefs[unitDefID].name==Newton_NAME)
		and (unitTeam==GetMyTeamID()) then
			NewtonStack[unitID] = NewtonAI:new(unitID);
		end
end

function widget:UnitDestroyed(unitID) 
	if not (NewtonStack[unitID]==nil) then
		NewtonStack[unitID]=NewtonStack[unitID]:unset();
	end
end

function widget:GameFrame(n) 	
	if (n%UPDATE_FRAME==0) then
		for _,newton in pairs(NewtonStack) do
			newton:handle()
		end
	end
end


function deepcopy(orig)
    local orig_type = type(orig)
    local copy
    if orig_type == 'table' then
        copy = {}
        for orig_key, orig_value in next, orig, nil do
            copy[deepcopy(orig_key)] = deepcopy(orig_value)
        end
        setmetatable(copy, deepcopy(getmetatable(orig)))
    else
        copy = orig
    end
    return copy
end

--- COMMAND HANDLING

function widget:CommandNotify(cmdID, params, options)
	if selectedNewtons ~= nil then
		if (cmdID == CMD_TOGGLE_NewtonAI)then
			local toggleStateGot = false
			local toggleState
			for i=1, #selectedNewtons do
				if (NewtonStack[selectedNewtons[i]])then
					if (toggleStateGot == false)then
						toggleState = NewtonStack[selectedNewtons[i]]:getToggleState()
						toggleStateGot = true
					end
					if (toggleState) then
						NewtonStack[selectedNewtons[i]]:toggleOff()
					else
						NewtonStack[selectedNewtons[i]]:toggleOn()
					end
				end
			end
			return true
		end
	end
end

function widget:SelectionChanged(selectedUnits)
	selectedNewtons = filterNewtons(selectedUnits)
end

function filterNewtons(units)
	local filtered = {}
	local n = 0
	for i = 1, #units do
		local unitID = units[i]
		if (NewtonUnitDefID == GetUnitDefID(unitID)) then
			n = n + 1
			filtered[n] = unitID
		end
	end
	if n == 0 then
		return nil
	else
		return filtered
	end
end

function widget:CommandsChanged()
	if selectedNewtons then
		local customCommands = widgetHandler.customCommands
		customCommands[#customCommands+1] = cmdToggleNewtonAI
	end
end


-- The rest of the code is there to disable the widget for spectators
local function DisableForSpec()
	if GetSpecState() then
		widgetHandler:RemoveWidget()
	end
end


function widget:Initialize()
	DisableForSpec()
	local units = GetTeamUnits(GetMyTeamID())
	for i=1, #units do
		DefID = GetUnitDefID(units[i])
		if (UnitDefs[DefID].name==Newton_NAME)  then
			if  (NewtonStack[units[i]]==nil) then
				NewtonStack[units[i]]=NewtonAI:new(units[i])
			end
		end
	end
end


function widget:PlayerChanged (playerID)
	DisableForSpec()
end