local U = require "scriptbank\\utillib"
local Q  = require "scriptbank\\quatlib"
local rad   = math.rad
local deg   = math.deg 
local floor = math.floor
local atan  = math.atan2
local abs   = math.abs
local sqrt  = math.sqrt


local reset_time = 1500 --time until the pointer gets reset automatically (low time stops it taking a long time to return for long paths)

isObjective = {}
current_objective = nil 
local state = {}
epress = 0

--[[
set 'current_objective = #' in your scripts to update the path 
i.e. current_objective = e
or   current_objective = 12 (where 12 = the entity you want to lead the player to)
--]]

function quest_path_init(e)
		state[e] = "reset path"
		CollisionOff(e)
		CharacterControlManual(e)
		Hide(e)
end 

function quest_path_main(e)
	--[[
	if g_KeyPressE == 1 then 
		if epress == 0 then 
			epress = 1 
			current_objective = AddQuestObjective()
		end 
	else 
		epress = 0
	end 
	
	if g_KeyPressQ == 1 then 
		start = 1 
	end 	
	
	if start == nil then 
		return 
	end 
	--]]	
	local co = current_objective
	local x,y,z = GetEntityPosAng(e)
	if co ~= nil then 
		local ox,oy,oz = GetEntityPosAng(co)
	end
	local obj = g_Entity[e]['obj']
	local px,py,pz = g_PlayerPosX,g_PlayerPosY,g_PlayerPosZ
	if state[e] == "reset path" then 
		local tx,ty,tz = GetEntityPosAng(e)
		if U.CloserThan(px,py,pz,tx,ty,tz,70) then 
			--SetRotation(e,0,AIGetEntityAngleY(obj),0)
			if current_objective ~= nil then 
				Show(e)
				ModulateSpeed(e,1)
				StartTimer(e)
				state[e] = "find path"			
			end 
		else 
			Hide(e)
			ModulateSpeed(e,20)
			AIEntityGoToPosition(obj,px,pz)
			SetRotation(e,0,AIGetEntityAngleY(obj),0)
			MoveForward(e,AIGetEntitySpeed(obj)*1)
			AISetEntityPosition(obj,GetEntityPositionX(e),GetEntityPositionY(e),GetEntityPositionZ(e))
		end
	elseif state[e] == "find path" then 
		if U.CloserThan(x,y,z,ox,oy,oz,70) or GetTimer(e) > reset_time then 
			state[e] = "reset path"
		else 
			AIEntityGoToPosition(obj,ox,oz)
			local tang = AIGetEntityAngleY(obj)
			--Text(50,70,3,tang)
			SetRotation(e,0,tang,0)
			MoveForward(e,AIGetEntitySpeed(obj)*1)	
			AISetEntityPosition(obj,GetEntityPositionX(e),GetEntityPositionY(e),GetEntityPositionZ(e))				
		end 
	end 
	if current_objective ~= nil then 
		--Prompt("current objective = "..current_objective.." , AI char state = "..state[e])
	else 
		--TextCenterOnX(50,80,3,"no current objective")
	end
end 

function AddQuestObjective()
	local dist = 99999999
	local px,py,pz = g_PlayerPosX,g_PlayerPosY,g_PlayerPosZ
	local closest_obj = nil
	for a,b in pairs (isObjective) do 
		local ox,oy,oz = GetEntityPosAng(a)
		local tdist = TCloserThan(px,py,pz,ox,oy,oz)
		if tdist < dist then 
			dist = tdist
			closest_obj = a 		
		end 
	end 
	return closest_obj
end 

function TCloserThan( x1, y1, z1, x2, y2, z2)
	local dx, dy, dz = x1 - x2, y1 - y2, z1 - z2
	return (dx*dx+dy*dy+dz*dz)
end