local U = require "scriptbank\\utillib"
local Q = require "scriptbank\\quatlib"
local lightNum = {}
local attachTo = {}
local offx,offy,offz,offax,offay,offaz = {},{},{},{},{},{}
attachLightToMe = {}
local rad = math.rad
local mode = {}
local offq = {}

--[[
*light modes*
use name "spin" for a spinning light effect
use name "search" for a searching effect
use name "fade" for a fade in / out effect
--]]
local spin_speed = {}
local spin_axis = {}
local search_speed = {}
local search_axis = {}
local search_range = {}
local fade_speed = {}
local fade_range = {}
local start_angle = {}
local start_fade = {}
local fade_direction = {}
local search_direction = {}

function light_npc_init_name(e,name)
	--mode settings info
	--[[
	spin settings;
		spin_speed[e] = higher = faster, negative = opposite direction
		spin_axis[e] = "x" / "y" / "z"
	search settings;
		search_speed[e] = higher = faster
		search_axis[e] = "x" / "y" / "z"
		search_range[e] = the amount the light will rotate before changing direction = 1~359
	fade settings;
		fade_speed[e] = higher = faster flicker 
		fade_range[e] = change in intensity of light = higher = more change 
		--you should set this based on the 'range' value of the light's property panel
	--]]
	--change the mode settings here 
	spin_speed[e] = 1 
	spin_axis[e] = "y"
	search_speed[e] = 1
	search_axis[e] = "y"
	search_range[e] = 90 
	fade_speed[e] = 10
	fade_range[e] = 2500
	--done with mode settings
  lightNum[e] = GetEntityLightNumber(e)--change 2 to the entity number of the light
	--change 'nil' to the entity number of the npc
	--or place the light next to entity for automatic assignment
	--*make sure entity has 'attachLightToMe[e] = e' in the script*
	attachTo[e] = nil 	
	mode[e] = name 
	if string.find(mode[e],string.lower("spin")) ~= nil then 
		mode[e] = "spin"
	elseif string.find(mode[e],string.lower("search")) ~= nil then 
		mode[e] = "search"
	elseif string.find(mode[e],string.lower("fade")) ~= nil then 
		mode[e] = "fade"
	end 
	if mode[e] == "spin" then 
		if search_axis[e] == "x" then 			
			start_angle[e] = GetEntityAngleX(e)
		elseif search_axis[e] == "z" then 
			start_angle[e] = GetEntityAngleZ(e)
		else 
			start_angle[e] = GetEntityAngleY(e)
		end 
	elseif mode[e] == "search" then 
		start_angle[e] = 0
		if search_speed[e] > 0 then 
			search_direction[e] = 1 
		else 
			search_direction[e] = -1
		end 
	elseif mode[e] == "fade" then 
		start_fade[e] = GetLightRange(lightNum[e])
		if fade_speed[e] > 0 then 
			fade_direction[e] = 1 
		else 
			fade_direction[e] = -1
		end 
	end 
end
function light_npc_main(e)
	if attachTo[e] == nil then 
		local x1,y1,z1 = GetLightPosition(lightNum[e])
		local dist1 = 999999
		for a,_ in pairs (attachLightToMe) do 
			local x2,y2,z2 = GetEntityPosAng(a)
			local dist2 = sqrd(x1,z1,x2,z2)
			if dist2 < dist1 then 
				attachTo[e] = a 
				dist1 = dist2
			end 
		end
		if attachTo[e] == nil then 
			attachTo[e] = -1
			return 
		end 
		--get the entity pos & angles values we are attaching too
		local x, y, z, Ax, Ay, Az = GetEntityPosAng(attachTo[e])
		--get our own (light) values 
		local lx,ly,lz = GetLightPosition(lightNum[e])
		local lax,lay,laz = GetEntityAngleX(e),GetEntityAngleY(e),GetEntityAngleZ(e)
		--work out the offsets (done once at map start)
		offx[e] = lx-x
		offy[e] = ly-y 
		offz[e] = lz-z 
		--workout and store the angle offset of the light as vector for later
		offax[e] = rad(GetEntityAngleX(e)) 
		offay[e] = rad(GetEntityAngleY(e)) 
		offaz[e] = rad(GetEntityAngleZ(e)) 
	else 
		--this part is run during the update
		if attachTo[e] == -1 then 
			return 
		end
		--place the light based on the new position + our offset
		local x, y, z, Ax, Ay, Az = GetEntityPosAng(attachTo[e])
		local xA, yA, zA = rad( Ax ), rad( Ay ), rad( Az )
		--work out the angle of the entity + our angle offset
		local xv, yv, zv = U.Rotate3D( 0, 0, 1, xA+offax[e], yA+offay[e], zA+offaz[e])
		local xo, yo, zo =  U.Rotate3D( offx[e], offy[e], offz[e], xA, yA, zA )
		if mode[e] == "fade" then 
			local fade = GetLightRange(lightNum[e])
			fade = fade + (fade_speed[e]*fade_direction[e])
			if fade < start_fade[e]-fade_range[e] or fade > start_fade[e]+fade_range[e] then 
				fade_direction[e] = fade_direction[e]*-1
			end
			--PromptLocal(e,fade)
			SetLightRange(lightNum[e],fade)
			xo, yo, zo =  U.Rotate3D( offx[e], offy[e], offz[e], xA, yA, zA )
		elseif mode[e] == "spin" then 
			start_angle[e] = start_angle[e] + spin_speed[e]
			if start_angle[e] > 359 then 
				start_angle[e] = start_angle[e]-360
			elseif start_angle[e] < 0 then 
				start_angle[e] = start_angle[e]+360
			end
			--PromptLocal(e,round(start_angle[e],2))
			start_angle[e] = rad(start_angle[e])			
			if spin_axis[e] == "x" then 
				xv, yv, zv = U.Rotate3D( 0, 0, 1, (xA+start_angle[e])+offax[e], yA+offay[e], zA+offaz[e])
				xo,yo,zo =  U.Rotate3D( offx[e], offy[e], offz[e], xA+start_angle[e], yA, zA )				
			elseif spin_axis[e] == "z" then 
				xv, yv, zv = U.Rotate3D( 0, 0, 1, xA+offax[e], yA+offay[e], (zA+start_angle[e])+offaz[e])
				xo, yo, zo =  U.Rotate3D( offx[e], offy[e], offz[e], xA, yA, zA+start_angle[e] )
			else 
				xv, yv, zv = U.Rotate3D( 0, 0, 1, xA+offax[e], (yA+start_angle[e])+offay[e], zA+offaz[e])
				xo, yo, zo =  U.Rotate3D( offx[e], offy[e], offz[e], xA, yA+start_angle[e], zA )
			end			
			start_angle[e] = math.deg(start_angle[e])			
		elseif mode[e] == "search" then 
			start_angle[e] = start_angle[e] + (search_speed[e]*search_direction[e])
			if start_angle[e] > search_range[e] or start_angle[e] < search_range[e]*-1 then 
				search_direction[e] = search_direction[e]*-1
			end 
			start_angle[e] = rad(start_angle[e])			
			if search_axis[e] == "x" then 
				xv, yv, zv = U.Rotate3D( 0, 0, 1, (xA+start_angle[e])+offax[e], yA+offay[e], zA+offaz[e])
				xo,yo,zo =  U.Rotate3D( offx[e], offy[e], offz[e], xA+start_angle[e], yA, zA )		
			elseif search_axis[e] == "z" then 
				xv, yv, zv = U.Rotate3D( 0, 0, 1, xA+offax[e], yA+offay[e], (zA+start_angle[e])+offaz[e])
				xo, yo, zo =  U.Rotate3D( offx[e], offy[e], offz[e], xA, yA, zA+start_angle[e] )
			else 
				xv, yv, zv = U.Rotate3D( 0, 0, 1, xA+offax[e], (yA+start_angle[e])+offay[e], zA+offaz[e])
				xo, yo, zo =  U.Rotate3D( offx[e], offy[e], offz[e], xA, yA+start_angle[e], zA )
			end 	
			start_angle[e] = math.deg(start_angle[e])						
		end
		SetLightPosition ( lightNum[e], x + xo, y + yo, z + zo )
		SetLightAngle( lightNum[e], xv, yv, zv )
		--PromptLocal(e,round(xv,2).."  "..round(yv,2).."   "..round(zv,2))
	end 
end 

function sqrd( x1, z1, x2, z2 )
	local dx, dz = x1 - x2, z1 - z2
	return dx*dx+dz*dz
end

function Q.Sub (q1, q2)
	return { w = q1.w - q2.w, x = q1.x - q2.x, y = q1.y - q2.y, z = q1.z - q2.z }
end

function round(num, numDecimalPlaces)
  local mult = 10^(numDecimalPlaces or 0)
  return math.floor(num * mult + 0.5) / mult
end