-- LUA Script - precede every function and global member with lowercase name of script + '_main'
-- Default script - does nothing.
local animationSpeed = {}
local animSet = {}
local speed = {}
local speedSet = {}
local timer = {}
local timer2 = {}
local timer3 = {}
local leader
local randomHeight = {}
local randomRange = {}
local speedFlee = {}
local speedSwim = {}

function flock_follower_init(e)
animationSpeed[e] = 1
animSet[e] = 0
speed[e] = 30
speedSet[e] = 0
leader = 1
timer[e] = 0
timer2[e] = 0
timer3[e] = 0
leader = 1
randomHeight[e] = 0
randomRange[e] = 0
speedFlee[e] = 0
speedSwim[e] =30
end

function flock_follower_main(e)

CollisionOff(e)
if GetTimer(e) > timer[e] + 5000 then
	randomHeight[e] = math.random(-20, 20)
	randomRange[e] = math.random(-20,20)
	speedFlee[e] = 150 + math.random(-50,50) + e
	speedSwim[e] = 30+ math.random(-5,5)
	timer[e] = GetTimer(e)
end
if g_Entity[e]['y'] < GetTerrainHeight(g_Entity[e]['x'],g_Entity[e]['z']) + 5 then
	MoveUp(e,10)
end

if g_Entity[e]['y']  < (g_Entity[leader]['y'] + randomHeight[e]) then
	MoveUp(e,5)
end

if g_Entity[e]['y'] > (g_Entity[leader]['y'] + randomHeight[e]) then
	MoveUp(e,-5)
end

if animSet[e] == 0 then
	animationSpeed[e] = math.random(1,10)
	ModulateSpeed(e,(1+1/animationSpeed[e]))
	animSet[e]=1
end

if	speedSet[e] == 0 then
	speed[e] = 30+ math.random(0,5)
	speedSet[e] = 1
end

if LeaderDistance(e) > 150 then
SetAnimationSpeedModulation(e,3)
CollisionOff(e)
speed[e] = speedFlee[e]
CollisionOn(e)
else
SetAnimationSpeedModulation(e,1)
CollisionOff(e)
speed[e] = speedSwim[e]
CollisionOn(e)
end

RotateToPointSlowly(e,g_Entity[leader]['x']+randomRange[e],g_Entity[leader]['z']+ randomRange[e],2)
MoveForward(e,speed[e])

end

function LeaderDistance(e)
if g_Entity[e] ~= nil and g_Entity[leader] ~= 0 then
	local disx = g_Entity[e]['x'] - g_Entity[leader]['x'] 
	local disz = g_Entity[e]['z'] - g_Entity[leader]['z'] 
	return math.sqrt(disx^2 + disz^2)
end
end


function RotateToPointSlowly(e,x,z,v)
if g_Entity[e] ~= nil and x > 0 and z > 0 then
if v == nil then
v = 1 
end
local destx = x - g_Entity[e]['x']
local destz = z - g_Entity[e]['z']
local angleneeded = math.atan2(destx,destz)
angleneeded = angleneeded * (180.0 / math.pi)
if angleneeded < 0 then
angleneeded = 360 + angleneeded
elseif angleneeded > 360 then
angleneeded = angleneeded - 360
end
local current_angy = g_Entity[e]['angley']
while current_angy < 0 or current_angy > 360 do
if current_angy <= 0 then
current_angy = 360 + current_angy
elseif current_angy > 360 then
current_angy = current_angy - 360
end
end
local L = angleneeded - v
local R = angleneeded + v
if L <= 0 then
L = 360 + L 
elseif L > 360 then
L = L - 360
end
if R <= 0 then
R = 360 + R
elseif R > 360 then
R = R - 360
end
 
--if not already facing the target direction (+/- the rotation speed)
if current_angy < L or current_angy > R then
--do it in 2 halfs so we can account for 0/360 wrap
if current_angy > 180 then
if angleneeded > current_angy - 180 and angleneeded < current_angy then
current_angy = current_angy - v
else
current_angy = current_angy + v
end
else
if angleneeded < current_angy + 180 and angleneeded > current_angy then
current_angy = current_angy + v
else
current_angy = current_angy - v
end
end
SetRotation(e,0,current_angy,0)
return current_angy
end
end
end