-- LUA Script - precede every function and global member with lowercase name of script + '_main'
-- Default script - does nothing.
local maxheightachieved = {}
local flying = {}
local soaring = {}
local landing = {} 
local walking = {}
local state = {}
local aggressive = {}
local animationcomplete = {}
local init_flight = {}
local ascending = {}
local soarcomplete = {}
local huntcomplete = {}
local ascentcomplete = {}
local descentcomplete = {}
local started = {}
local started2 = {}
local descending = {}
local hunting = {}
local groundattack = {}
local airattack = {}
local attacking = {}
local attacktype = {}
local hitting = {}
local attackstarted = {}
local starthealth = {}
local setpos = {}
local xpos = {}
local ypos = {}
local zpos = {}
local timer = {}
local timed = {}
local outofbounds = {}
local direction = {}
local wyvernpos = {}
local nvolume = {}
local maxvolume = {}
local minvolume = {}
local death = {}
local dead = {}
local startedbiting = {}
local wyvrandom = {}
local randomset = {}
local rotaterandom = {}
local rotateset = {}
local terrainheight = {}

function wyvern_init(e)

maxheightachieved[e] = 0
soaring[e] = 0
flying[e] = 0
landing[e] = 0
walking[e] = 0
state[e] = ""
animationcomplete[e] = 0
aggressive[e] = 0
init_flight[e] = 0
ascending[e] = 0
soarcomplete[e] = 0
huntcomplete[e] = 0
ascentcomplete[e] = 0
started[e] = 0
started2[e] = 0
descending[e] = 0
descentcomplete[e] = 0
hunting[e] = 0
groundattack[e] = 0
airattack[e] = 0
attacking[e] = 0
attacktype[e] = 0
hitting[e] = 0
attackstarted[e] = 0
setpos[e] = 0
xpos[e] = 0
ypos[e] = 0
zpos[e] = 0
timer[e] = 0
timed[e] = 0
outofbounds[e] = 0
direction[e] = 0
wyvernpos[e] = 0
nvolume[e] = 0
maxvolume[e] = 100
minvolume[e] = 1
death[e] = 0
dead[e] = 0
startedbiting[e] = 0
wyvrandom[e] = 0
randomset[e] = 0
rotaterandom[e] = 0
rotateset[e] = 0
terrainheight[e] = 600

end

function wyvern_main(e)

Prompt(g_PlayerPosY)

--terrainheight[e] = GetTerrainHeight(g_Entity[e]['x'],g_Entity[e]['z'])

if randomset[e] == 0 then
	wyvrandom[e] = math.random(0,10000)
	randomset[e] = 1
end

if rotateset[e] == 0 then
	rotaterandom[e] = math.random(0,1)
	rotateset[e] = 1
end
if rotaterandom[e] == 0 then
	rotaterandom[e] = -1
end
	


--stops death animation
if GetAnimationFrame(e) == 807 then
	dead[e] = 1
	StopAnimation(e)
end

--keeps health above a certain level during flight
if g_Entity[e]['health'] < 500 and g_Entity[e]['y'] > (terrainheight[e]+10) then
	SetEntityHealth(e,490)
		
end

-- sets sound volume
nvolume[e] = maxvolume[e] - ( GetPlayerDistance(e) / 300.0 )
if nvolume[e] < minvolume[e] then
  StopSound(e,0)
 end
 SetSoundVolume(nvolume[e]) 

 --gets initial position
if setpos[e] == 0 then
	xpos[e] = g_Entity[e]['x']
	zpos[e] = g_Entity[e]['z']
	ypos[e] = g_Entity[e]['y']
	setpos[e] = 1
end

-- play wing flapping sound
if GetAnimationFrame(e) == 165 or GetAnimationFrame(e) == 750 then
	PlaySound(e,0)
end

--play screeching sound
if GetAnimationFrame(e) == 480 then
	PlaySound(e,1)
end

--checks for out of bounds
if WyvernDistance(e) > 10000 then
	outofbounds[e] = 1
	timer[e] = 20
elseif WyvernDistance(e) < 10000 then
	outofbounds[e] = 0
end


if outofbounds[e] == 0 then	
	direction[e] = math.random(0,1)
	if direction[e] == 0 then direction[e] = -1
	end
end

--returns to original area of out of bounds
if outofbounds[e] == 1 then
	if started2[e] == 0 then	
		StartTimer(e)
		wyvernpos[e] = WyvernDistance(e)
		started2[e] = 1
		end
	if GetTimer(e) > timer[e] then 
			if WyvernDistance(e) > wyvernpos[e] then
			RotateY(e,(60*direction[e]))
			end
		started[e] = 0
	end
end

--sets initial flight
if g_Entity[e]['y'] > (terrainheight[e] + 2500) then
	init_flight[e] = 1
end

--gets initial entity health
if starthealth[e] == nil then
	starthealth[e] = g_Entity[e]['health']
end

--if entity is damaged, change behaviour
if g_Entity[e]['health'] < starthealth[e] then
	aggressive[e] = 1
	ascending[e] = 0
end

--checks if descent is complete
if descending[e] == 1 and g_Entity[e]['y'] < (terrainheight[e]+400) then
	descentcomplete[e] = 1
	elseif descending[e] == 1 and g_Entity[e]['y'] > (terrainheight[e]+400) then
	descentcomplete[e] = 0
end

--checks if ascent is complete
if ascending[e] == 1 and g_Entity[e]['y'] > (terrainheight[e]+2500) then
	ascentcomplete[e] = 1
	soarcomplete[e] = 0
	elseif ascending[e] == 1 and g_Entity[e]['y'] < (terrainheight[e]+2500) then
	ascentcomplete[e] = 0
end

--if hunting and player close, changes behaviour
if hunting[e] == 1 and GetPlayerDistance(e) < 3000 then
	if state[e] ~= "aggressive" then
		g_Entity[e]['animating'] = 0
			state[e] = "aggressive"
	end
	aggressive[e] = 1
	hunting[e] = 0
end

if death[e] == 0 then

if g_Entity[e]['health'] > 500 then

if aggressive[e] == 0 then

--returns to original area of out of bounds
if outofbounds[e] == 1 then
	if started2[e] == 0 then	
		StartTimer(e)
		wyvernpos[e] = WyvernDistance(e)
		started2[e] = 1
	end
	if GetTimer(e) > timer[e] then 
			if WyvernDistance(e) > wyvernpos[e] then
			RotateY(e,(60*direction[e]))
			end
		started[e] = 0
	end

elseif outofbounds[e] == 0 then

--starts ascent
if init_flight[e] == 0 then
	if state[e] ~= "ascending" then
		g_Entity[e]['animating'] = 0
			state[e] = "ascending"
	end
	ascending[e] = 1
	flying[e] = 1
	walking[e] = 0
	landing[e] = 0
	aggressive[e] = 0
	
elseif init_flight[e] == 1 then

--set to soaring if ascent is complete
if soarcomplete[e] == 0 then
	if state[e] ~= "soaring" then
		g_Entity[e]['animating'] = 0
			state[e] = "soaring"
	end
	hunting[e] = 0
	soaring[e] = 1
	ascending[e] = 0
	flying[e] = 0
	walking[e] = 0
	landing[e] = 0
	
--sets to descent if soar is complete
	elseif soarcomplete[e] == 1 and descentcomplete[e] == 0 then
		if state[e] ~= "descending" then
		g_Entity[e]['animating'] = 0
			state[e] = "descending"
		end
		descending[e] = 1
		hunting[e] = 0
		soaring[e] = 0
		ascending[e] = 0
		flying[e] = 0
		walking[e] = 0
		landing[e] = 0
	
--sets to hunting is descent is complete	
	elseif soarcomplete[e] == 1 and descentcomplete[e] == 1 and huntcomplete[e] == 0 then
		if state[e] ~= "hunting" then
		g_Entity[e]['animating'] = 0
			state[e] = "hunting"
		end
		hunting[e] = 1
		descending[e] = 0
		soaring[e] = 0
		ascending[e] = 0
		flying[e] = 0
		walking[e] = 0
		landing[e] = 0

--	sets to ascent if hunt is complete	
	elseif soarcomplete[e] == 1 and descentcomplete[e] == 1 and huntcomplete[e] == 1 then
		if state[e] ~= "ascending" then
		g_Entity[e]['animating'] = 0
			state[e] = "ascending"
		end
		hunting[e] = 0
		descending[e] = 0
		soaring[e] = 0
		ascending[e] = 1
		flying[e] = 0
		walking[e] = 0
		landing[e] = 0
		
end
end
end

--sets behaviour once wyvern is aggressive
elseif aggressive[e] == 1 then
		airattack[e] = 1
		groundattack[e] = 0
	
end

--behaviour if wyvern is badly injured
elseif g_Entity[e]['health'] < 500 then

--wyvern descends
	if g_Entity[e]['y'] > (terrainheight[e]+70) then 
		if state[e] ~= "descending" then
			g_Entity[e]['animating'] = 0
			state[e] = "descending"
		end
	hunting[e] = 0
	descending[e] = 1
	soaring[e] = 0
	flying[e] = 0
	walking[e] = 0
	ascending[e] = 0
	landing[e] = 0
	airattack[e] = 0
	groundattack[e] = 0
	end	

--if wyvern is close to the ground then it lands	
	if g_Entity[e]['y'] > (terrainheight[e]+60) and g_Entity[e]['y'] < (terrainheight[e]+70) then
		if state[e] ~= "landing" then
			g_Entity[e]['animating'] = 0
			state[e] = "landing"
		end
	hunting[e] = 0
	descending[e] = 0
	soaring[e] = 0
	flying[e] = 0
	ascending[e] = 0
	walking[e] = 0
	landing[e] = 1
	airattack[e] = 0
	groundattack[e] = 0
	
	end

--sets to attack if on the ground	
	if g_Entity[e]['y'] < (terrainheight[e]+2) then
		
	hunting[e] = 0
	descending[e] = 0
	soaring[e] = 0
	flying[e] = 0
	ascending[e] = 0
	walking[e] = 0
	landing[e] = 0
	airattack[e] = 0
	groundattack[e] = 1
	end
end
	

--hunting behaviour
if hunting[e] == 1 then
	if g_Entity[e]['animating'] == 0 then
		SetAnimationFrames(161,261)
		LoopAnimation(e)
		g_Entity[e]['animating'] = 1
	end 
	if started[e] == 0 then
		StartTimer(e)
		started[e] = 1
	end
	if GetTimer(e) > (20000 + wyvrandom[e]) then
		huntcomplete[e] = 1
		started[e] = 0
	end
	MoveForward(e,200)
	RotateY(e,(5*rotaterandom[e]))
end


--descent behaviour	
if descending[e] == 1 then
	if g_Entity[e]['animating'] == 0 then
		SetAnimationFrames(7,107)
		LoopAnimation(e)
		g_Entity[e]['animating'] = 1
	end 
	MoveForward(e,250)
	MoveUp(e,-50)
	if g_Entity[e]['health'] < starthealth[e] then
		RotateToPlayerSlowly(e,5)
	end
end


--soaring behaviour
if soaring[e] == 1 then
	if g_Entity[e]['animating'] == 0 then
		SetAnimationFrames(7,107)
		LoopAnimation(e)
		g_Entity[e]['animating'] = 1
	end 
	if started[e] == 0 then
		StartTimer(e)
		started[e] = 1
	end
	if GetTimer(e) > (20000 + wyvrandom[e]) then
		soarcomplete[e] = 1
		started[e] = 0
	end
	MoveForward(e,100)
	RotateY(e,(5*rotaterandom[e]))
	ascentcomplete[e] = 0
	descentcomplete[e] = 0
	huntcomplete[e] = 0
end

--ascent behaviour
if ascending[e] == 1 then
	if g_Entity[e]['animating'] == 0 then
		SetAnimationFrames(161,261)
		LoopAnimation(e)
		g_Entity[e]['animating'] = 1
	end 
	MoveForward(e,100)
	MoveUp(e,50)	

end


--flying behaviour
if flying[e] == 1 then
	ModulateSpeed(e,2)
	if g_Entity[e]['animating'] == 0 then
		SetAnimationFrames(161,261)
		LoopAnimation(e)
		g_Entity[e]['animating'] = 1
	end 
	MoveForward(e,40)
	MoveUp(e,20)
	if GetAnimationFrame(e) == 161 then	
		animationcomplete[e] = 0
	end
	if GetAnimationFrame(e) == 261 then	
		animationcomplete[e] = 1
	end
 end
 
 
 --landing behaviour
if landing[e] == 1 then
	ModulateSpeed(e,1.5)
	if g_Entity[e]['animating'] == 0 then
		SetAnimationFrames(300,400)
		PlayAnimation(e)
		g_Entity[e]['animating'] = 1
	end 
	MoveForward(e,100)
	if g_Entity[e]['y'] > terrainheight[e] then 
		MoveUp(e,-30)
	end
	if GetAnimationFrame(e) == 300 then	
		animationcomplete[e] = 0
	end
	if GetAnimationFrame(e) == 400 then	
		animationcomplete[e] = 1
	end
end

--approaches player from the air
if airattack[e] == 1 and GetPlayerDistance(e) > 400  then
	if state[e] ~= "airattack" then
		g_Entity[e]['animating'] = 0
		state[e] = "airattack"
	end
	if g_Entity[e]['y'] > (terrainheight[e]+50) then
		MoveUp(e,-50)
	end
	ModulateSpeed(e,3)
	
	if g_Entity[e]['animating'] == 0 then
		SetAnimationFrames(652,752)
		LoopAnimation(e)
		g_Entity[e]['animating'] = 1

	end
	MoveForward(e,300)
	RotateToPlayerSlowly(e,5)
--aerial attack	behaviour
 elseif airattack[e] == 1 and GetPlayerDistance(e) < 400 then
	if state[e] ~= "attacking" then
		g_Entity[e]['animating'] = 0
		state[e] = "attacking"
	end
	if g_Entity[e]['y'] > (terrainheight[e]+100) then
		MoveUp(e,-100)
	end
	
	if animationcomplete[e] == 1 then
		attacktype[e] = math.random(0,1)
		animationcomplete[e] = 0
		g_Entity[e]['animating'] = 0
	end
	MoveForward(e,200)
	RotateToPlayerSlowly(e,8)
	
--chooses between attack types
	if attacktype[e] == 0 then
		if g_Entity[e]['animating'] == 0 then
			SetAnimationFrames(451,551)
			PlayAnimation(e)
			g_Entity[e]['animating'] = 1
		end
		if GetAnimationFrame(e) > 500 and GetAnimationFrame(e) < 502 then
			hitting[e] = 1
		
		elseif GetAnimationFrame(e) < 500 or GetAnimationFrame(e) > 502 then
			hitting[e] = 0
		end
	
		if GetAnimationFrame(e) == 451 then
			animationcomplete[e] = 0
		end
		if GetAnimationFrame(e) == 551 then
			animationcomplete[e] = 1
		end
		if hitting[e] == 1 and GetPlayerDistance(e) < 300 then
			HurtPlayer(e,10)
		end
	end
	if attacktype[e] == 1 then
		if g_Entity[e]['animating'] == 0 then
			SetAnimationFrames(551,651)
			PlayAnimation(e)
			g_Entity[e]['animating'] = 1
		end
		if GetAnimationFrame(e) > 608 and GetAnimationFrame(e) < 610 then
			hitting[e] = 1
		end
		
		if GetAnimationFrame(e) < 608 and GetAnimationFrame(e) > 610 then
			hitting[e] = 0
		end
	
		if GetAnimationFrame(e) == 551 then
			animationcomplete[e] = 0
		end
		if GetAnimationFrame(e) == 651 then
			animationcomplete[e] = 1
		end
		if hitting[e] == 1 and GetPlayerDistance(e) < 300 then
			HurtPlayer(e,10)
		end
	end
	
end
--approaches player on the ground

if GetAnimationFrame(e) > 448 and GetAnimationFrame(e) < 451 then
		startedbiting[e] = 0
end

if groundattack[e] == 1 then
	if g_Entity[e]['y'] > (terrainheight[e] + 2) then
		MoveUp(e,-50)
	end
	
	if g_Entity[e]['y'] < (terrainheight[e] - 2) then
		MoveUp(e,50)
	end

	if GetPlayerDistance(e) < 200 then
		attacking[e] = 1
	end

	if GetAnimationFrame(e) > 430 and GetAnimationFrame(e) < 433 then
		hitting[e] = 1
	end
		
	if GetAnimationFrame(e) < 430 or GetAnimationFrame(e) > 433 then
		hitting[e] = 0
	end
	
	if GetAnimationFrame(e) > 400 and GetAnimationFrame(e) < 403 then
		animationcomplete[e] = 0
		startedbiting[e] = 1
	end
		
	if GetAnimationFrame(e) > 448 and GetAnimationFrame(e) < 451 then
		animationcomplete[e] = 1
		startedbiting[e] = 0
		attacking[e] = 0
	end

	if hitting[e] == 1 and GetPlayerDistance(e) < 300 then
		HurtPlayer(e,10)
	end
	
--	if GetAnimationFrame(e) > 108 and GetAnimationFrame(e) < 111 then
--		animationcomplete[e] = 0
--	end
	
--	if GetAnimationFrame(e) > 157 and GetAnimationFrame(e) < 160 then
--		animationcomplete[e] = 1
--	end
end

if groundattack[e] == 1 and GetPlayerDistance(e) > 200 and startedbiting[e] == 0 and attacking[e] == 0 then
	if attackstarted[e] == 0 then
		SetEntityHealth(e,490)
		attackstarted[e] = 1
	end
	if state[e] ~= "groundattack" then
		g_Entity[e]['animating'] = 0
		state[e] = "groundattack"
	end
		
	ModulateSpeed(e,2)
	if g_Entity[e]['animating'] == 0 then
		SetAnimationFrames(109,159)
		LoopAnimation(e)
		g_Entity[e]['animating'] = 1
	end 
	MoveForward(e,200)
	RotateToPlayerSlowly(e,5)
	if GetAnimationFrame(e) == 109 then
		animationcomplete[e] = 0
	end
		
	if GetAnimationFrame(e) == 159 then
		animationcomplete[e] = 1
	end
	

--ground attack behaviour

	elseif groundattack[e] == 1 and GetPlayerDistance(e) < 200 then 
		if state[e] ~= "attacking" then
			g_Entity[e]['animating'] = 0
			state[e] = "attacking"
			attacking[e] = 1
		end
	
			
end
if attacking[e] == 1 then
		ModulateSpeed(e,4)
		if g_Entity[e]['animating'] == 0  then
			SetAnimationFrames(400,450)
			LoopAnimation(e)
			g_Entity[e]['animating'] = 1
		end
	end
end

--check for death and play death animation
if g_Entity[e]['health'] < 1 and dead[e] == 0 and g_Entity[e]['y'] < (terrainheight[e]+5) then
	if state[e] ~= "dead" then
		g_Entity[e]['animating'] = 0
		state[e] = "dead"
	end
	death[e] = 1
	ModulateSpeed(e,1.0)
	if g_Entity[e]['animating'] == 0  then
			SetAnimationFrames(759,807)
			PlayAnimation(e)
			g_Entity[e]['animating'] = 1
	end

	StopSound(e)
end
end


--gets lateral distance from starting point
function WyvernDistance(e)
  wyvernDX = (g_Entity[e]['x'] - xpos[e])
  wyvernDY = (g_Entity[e]['y'] - ypos[e])
  wyvernDZ = (g_Entity[e]['z'] - zpos[e])
  
  return math.sqrt(math.abs(wyvernDX*wyvernDX)+math.abs(wyvernDZ*wyvernDZ));
end