-- LUA Script - precede every function and global member with lowercase name of script + '_main'
-- Default script - does nothing.
-- Add this to always active entity - only one is needed

local Q = require "scriptbank\\quatlib"

local deg    = math.deg
local rad    = math.rad
local sin    = math.sin
local cos    = math.cos
local atan   = math.atan2
local tan    = math.tan
local pi     = math.pi
local abs    = math.abs
local modf	 = math.modf
local sqrt   = math.sqrt

local pickUpDistance = 150

local pickUppableEntity = {Ent = nil}

local function Rotate3D (x, y, z, xrot, yrot, zrot) 

	function RotatePoint2D (x, y, Ang)  -- Ang in radians
		local Sa, Ca = sin(Ang), cos(Ang)
		return x*Ca - y*Sa, x*Sa + y*Ca
	end
 
	local NX, NY, NZ = x, y, z

	-- X
	NZ, NY = RotatePoint2D (NZ, NY, -xrot)
	
	-- Y
	NX, NZ = RotatePoint2D (NX, NZ, -yrot)
	
	-- Z
	NY, NX = RotatePoint2D (NY, NX, -zrot)

	return NX, NY, NZ
end

local function WrapAng(Ang)
	local RAng = Ang 
	while RAng >= 360 do
		RAng = RAng - 360
	end
	while RAng < 0 do
		RAng = RAng + 360
	end
	return RAng
end

function ray_collision_test_init(e)
	pickUppableEntity.Ent = nil
end

local function GetObjectSize(p)
	p.l, p.h, p.w = 0, 0, 0
	
	local Ent = g_Entity[p.Ent]
	
	local x, y, z = Ent.x, Ent.y, Ent.z
	local ax, ay, az = rad(Ent.anglex), rad(WrapAng(Ent.angley)), rad(Ent.anglez)	
	
	local xwi, yli, zwi = Rotate3D(1, 0, 0, ax, ay, az)
	local xli, yli, zli = Rotate3D(0, 0, 1, ax, ay, az)
	
	-- find height of object
	local height = y + 1
	local ignore = 0
	
	local newx, newz = x + xwi, z + zwi
	
	while IntersectAll(newx, height, newz, x, height, z, ignore) ~= p.Obj do
		newx, newz = newx + xwi, newz + zwi
	end
	while IntersectAll(newx, height, newz, x, height, z, ignore) == p.Obj do
		height = height + 10
	end
	while IntersectAll(newx, height, newz, x, height, z, ignore) ~= p.Obj do
		height = height - 1
	end
	
	p.h = height - y + 1
	
	local newy = y + height + 2
	
	local stX, stZ = newx, newz

	-- measure 'width'
	local foundEdge = false
	local fObj = 0
	
	while not foundEdge do
		fObj = IntersectAll(newx, newy, newz, newx, y, newz, ignore)
		if fObj == p.Obj then
			foundEdge = true
		elseif fObj ~= nil and fObj ~= 0 then
			ignore = fObj
		else
			newx, newz = newx - xwi, newz - zwi
		end
	end

	foundEdge = false
	ignore = 0
	
	while not foundEdge do
		fObj = IntersectAll(newx, newy, newz, newx, y, newz, ignore)
		if fObj ~= p.Obj then
			if fObj == nil or fObj == 0 then
				foundEdge = true
			else
				ignore = fObj
			end
		else
			newx, newz = newx - (xwi * 10), newz - (zwi * 10)
		end
	end
	
	foundEdge = false
	ignore = 0
	
	while not foundEdge do
		fObj = IntersectAll(newx, newy, newz, newx, y, newz, ignore)
		if fObj == p.Obj then
			foundEdge = true
		elseif fObj ~= nil and fObj ~= 0 then
			ignore = fObj
		else
			newx, newz = newx + xwi, newz + zwi
		end
	end

	local xd, zd = newx - stX, newz - stZ
	
	p.w = sqrt(xd*xd+zd*zd)
	
	-- measure 'length'
	newx, newz = x, z
	
	foundEdge = false
	ignore = 0
	
	while not foundEdge do
		fObj = IntersectAll(newx, newy, newz, newx, y, newz, ignore)
		if fObj ~= p.Obj then
			if fObj == nil or fObj == 0 then
				foundEdge = true
			else
				ignore = fObj
			end
		else
			newx, newz = newx - (xli * 10), newz - (zli * 10)
		end
	end
	
	foundEdge = false
	ignore = 0
	
	while not foundEdge do
		fObj = IntersectAll(newx, newy, newz, newx, y, newz, ignore) 
		if fObj == p.Obj then
			foundEdge = true
		elseif fObj ~= nil and fObj ~= 0 then
			ignore = fObj
		else
			newx, newz = newx + xli, newz + zli
		end
	end

	xd, zd = newx - x, newz - z
	
	p.l = (sqrt(xd*xd+zd*zd) + 1) * 2 
end

local function PrintDetails(p)
	if p.l > p.w then
		PromptLocal(p.Ent, p.Ent .. ", len=" .. p.l .. " width=" .. p.w .. " height=" .. p.h)
	else
		PromptLocal(p.Ent, p.Ent .. ", len=" .. p.w .. " width=" .. p.l .. " height=" .. p.h)
	end
end

function ray_collision_test_main(e)

	if pickUppableEntity.Ent ~= nil then
		PrintDetails(pickUppableEntity)
	end
	
	-- Only check every 10th second
	if not scheduler(e) then return end
	
	local x, y, z = g_PlayerPosX, g_PlayerPosY + 35, g_PlayerPosZ
	
	local rayX, rayY, rayZ = 0, 0, pickUpDistance
	
	local paX, paY, paZ = rad(g_PlayerAngX), rad(g_PlayerAngY), rad(g_PlayerAngZ)
	
	rayX, rayY, rayZ = Rotate3D(rayX, rayY, rayZ, paX, paY, paZ)
	
	local Pobj = IntersectAll(x, y, z, x + rayX, y + rayY, z + rayZ, 0)	

	if Pobj ~= 0 then
		for k,v in pairs(g_Entity) do
			if v.obj == Pobj then
				if pickUppableEntity.Ent ~= k then
					pickUppableEntity = {Ent = k, Obj = Pobj, pickedUp = false}
					GetObjectSize(pickUppableEntity)
				end
				return
			end
		end
	end
	
	pickUppableEntity.Ent = nil
end

----------------------------------------------------------------
-- Scheduler, this nifty little function keeps track of time. --
-- The main routine should be called every frame and returns  --
-- a flag indicating whether the passed in time has expired   --
-- since the last time it was called.                         --
-- If no time period is specified 100ms is used by default,   --
-- i.e. 1/10th of a second.                                   --
-- The caller can either ignore the return flag or use it to  --
-- trigger time sensitive functionality.                      --
-- A global value giving the frames per second count is also  --
-- generated, this can be used in script to make animations   --
-- independent of frames.                                     --
-- The reason this function is tied to an entity rather than  --
-- being global is so that each entity can be triggered at a  --
-- different time rather than all being triggered in the same --
-- frame. 
----------------------------------------------------------------
g_scheduler = {}

function scheduler(e, period)
	period = period or 100  -- defaults to tenths of a second (100ms)
 
	if g_Time == nil then return false end
	
	if g_scheduler[e] == nil then
	
		g_scheduler[e] = {frames_per_second      = 60,
						  period_accumulated     = math.random(0, period),
						  accumulated_time       = 0,
						  timer_value_last_frame = g_Time,
						  frame_counter          = 0};
						  
	-- 'test' mode sometimes doesn't clear Lua globals so if
	-- this appears to be the case initialise everything
    elseif g_scheduler[e].accumulated_time > 2000 then
	   
		g_scheduler[e].frames_per_second      = 60
		g_scheduler[e].period_accumulated     = math.random(0, period)
		g_scheduler[e].accumulated_time       = 0
		g_scheduler[e].timer_value_last_frame = g_Time
		g_scheduler[e].frame_counter          = 0
	end
	
	local entry = g_scheduler[e]
	local do_this_frame_flag = false
		
	entry.frame_counter = entry.frame_counter + 1

	local time_since_last_frame = g_Time - entry.timer_value_last_frame
	
	if (entry.period_accumulated + time_since_last_frame) > period then 
		
		entry.period_accumulated = (entry.period_accumulated + 
		                            time_since_last_frame) - period;  
		do_this_frame_flag = true
	else
		entry.period_accumulated = entry.period_accumulated + time_since_last_frame
	end

	if (entry.accumulated_time + time_since_last_frame) > 1000 then -- more than a second passed?

		entry.accumulated_time = (entry.accumulated_time + 
								  time_since_last_frame) - 1000;
		entry.frames_per_second = entry.frame_counter
		entry.frame_counter = 0
	else
		entry.accumulated_time = entry.accumulated_time + time_since_last_frame
	end

	entry.timer_value_last_frame = entry.timer_value_last_frame + time_since_last_frame 

	return do_this_frame_flag
end