--SFX ID to Sound object
local Sounds = {}

do
	local Figure = script.Parent.Parent
	Head = Figure:WaitForChild("Head")
	Humanoid = Figure:WaitForChild("Humanoid")
	
	Sounds[SFX.Died] = 			Head:WaitForChild("Died")
	Sounds[SFX.Running] = 		Head:WaitForChild("Running")
	Sounds[SFX.Swimming] = 		Head:WaitForChild("Swimming")
	Sounds[SFX.Climbing] = 		Head:WaitForChild("Climbing")
	Sounds[SFX.Jumping] = 		Head:WaitForChild("Jumping")
	Sounds[SFX.GettingUp] = 	Head:WaitForChild("GettingUp")
	Sounds[SFX.FreeFalling] = 	Head:WaitForChild("FreeFalling")
	Sounds[SFX.Landing] = 		Head:WaitForChild("Landing")
	Sounds[SFX.Splash] = 		Head:WaitForChild("Splash")
end

local Util
Util = {
	
	--Define linear relationship between (pt1x,pt2x) and (pt2x,pt2y). Evaluate this like at x.
	YForLineGivenXAndTwoPts = function(x,pt1x,pt1y,pt2x,pt2y)
		--(y - y1)/(x - x1) = m
		local m = (pt1y - pt2y) / (pt1x - pt2x)
		--float b = pt1.y - m * pt1.x;
		local b = (pt1y - m * pt1x)
		return m * x + b
	end;
	
	--Clamps the value of "val" between the "min" and "max"
	Clamp = function(val,min,max)
		return math.min(max,math.max(min,val))	
	end;
	
	--Gets the horizontal (x,z) velocity magnitude of the given part
	HorizontalVelocityMagnitude = function(Head)
		local hVel = Head.Velocity + Vector3.new(0,-Head.Velocity.Y,0)
		return hVel.magnitude	
	end;
	
	--Gets the vertical (y) velocity magnitude of the given part
	VerticalVelocityMagnitude = function(Head)
		return math.abs(Head.Velocity.Y)
	end;
	
	--Checks if Sound.Playing is usable
	SoundIsV2 = function(sound)
		return sound.IsLoaded
	end;
	
	--Setting Playing/TimePosition values directly result in less network traffic than Play/Pause/Resume/Stop
	--If these properties are enabled, use them.
	Play = function(sound)		
		if Util.SoundIsV2(sound) then
			if sound.TimePosition ~= 0 then
				sound.TimePosition = 0
			end
			if not sound.IsPlaying then
				sound.Playing = true
			end
		else
			sound:Play()
		end
		
	end;
	Pause = function(sound)
		if Util.SoundIsV2(sound) then
			if sound.IsPlaying then
				sound.Playing = false
			end
		else
			sound:Pause()
		end
	end;
	Resume = function(sound)
		if Util.SoundIsV2(sound) then
			if not sound.IsPlaying then
				sound.Playing = true
			end
		else
			sound:Resume()
		end
	end;
	Stop = function(sound)
		if Util.SoundIsV2(sound) then
			if sound.IsPlaying then
				sound.Playing = false
			end
			if sound.TimePosition ~= 0 then
				sound.TimePosition = 0
			end
		else
			sound:Stop()
		end
	end;
}

do
	-- List of all active Looped sounds
	local activeLoopedSounds = {}
	
	-- Last seen Enum.HumanoidStateType
	local activeState = nil
	
	-- Verify and set that the sound's .Looped property is the value of "looped"
	function verifyAndSetLoopedForSound(sound, looped)
		if sound.Looped ~= looped then
			sound.Looped = looped
		end
	end
	
	-- Verify and set that "sound" is in "activeLoopedSounds".
	function setSoundInActiveLooped(sound)
		for i=1, #activeLoopedSounds do
			if activeLoopedSounds[i] == sound then
				return
			end
		end	
		table.insert(activeLoopedSounds,sound)
	end
	
	-- Stop all active looped sounds except parameter "except". If "except" is not passed, all looped sounds will be stopped.
	function stopActiveLoopedSoundsExcept(except)
		for i=#activeLoopedSounds,1,-1 do
			if activeLoopedSounds[i] ~= except then
				Util.Pause(activeLoopedSounds[i])			
				table.remove(activeLoopedSounds,i)	
			end
		end
	end
	
	-- Table of Enum.HumanoidStateType to handling function
	local stateUpdateHandler = {
		[Enum.HumanoidStateType.Dead] = function()
			stopActiveLoopedSoundsExcept()
			local sound = Sounds[SFX.Died]
			verifyAndSetLoopedForSound(sound,false)
			Util.Play(sound)
		end;
		
		[Enum.HumanoidStateType.RunningNoPhysics] = function()
			stateUpdated(Enum.HumanoidStateType.Running)
		end;
		
		[Enum.HumanoidStateType.Running] = function()	
			local sound 
			local ray = Ray.new(Head.Position,Vector3.new(0,-15,0))
			local part1,pos1,norm1,mat1 = workspace:FindPartOnRay(ray,Head.Parent)
			if mat1 == Enum.Material.Water then
			sound = Sounds[SFX.Swimming]
			if activeState ~= Enum.HumanoidStateType.Swimming then
			activeState = Enum.HumanoidStateType.Swimming
				local splashSound = Sounds[SFX.Splash]
				splashSound.Volume = .1
				Util.Play(splashSound)
			end
			else
			if activeState == Enum.HumanoidStateType.Swimming then
				local splashSound = Sounds[SFX.Splash]
				splashSound.Volume = .1
				Util.Play(splashSound)
			end
			sound = Sounds[SFX.Running]
			activeState = Enum.HumanoidStateType.Running
			end
			verifyAndSetLoopedForSound(sound,true)
			stopActiveLoopedSoundsExcept(sound)
			
			if Util.HorizontalVelocityMagnitude(Head) > 0.5 then
				if not sound.IsPlaying then
					Util.Resume(sound)
				end
				setSoundInActiveLooped(sound)
			else
				stopActiveLoopedSoundsExcept()
			end
		end;
		
		[Enum.HumanoidStateType.Swimming] = function()
			if activeState ~= Enum.HumanoidStateType.Swimming and Util.VerticalVelocityMagnitude(Head) > 0.1 then
				local splashSound = Sounds[SFX.Splash]
				splashSound.Volume = Util.Clamp(
					Util.YForLineGivenXAndTwoPts(
						Util.VerticalVelocityMagnitude(Head), 
						100, 0.28, 
						350, 1),
					0,1)
				Util.Play(splashSound)
			end
			
			do
				local sound = Sounds[SFX.Swimming]
				verifyAndSetLoopedForSound(sound,true)
				stopActiveLoopedSoundsExcept(sound)
				if not sound.IsPlaying then
					Util.Resume(sound)
				end
				setSoundInActiveLooped(sound)
			end
		end;
		
		[Enum.HumanoidStateType.Climbing] = function()
			local sound = Sounds[SFX.Climbing]
			verifyAndSetLoopedForSound(sound,true)
			if Util.VerticalVelocityMagnitude(Head) > 0.1 then
				if not sound.IsPlaying then
					Util.Resume(sound)
				end				
				stopActiveLoopedSoundsExcept(sound)
			else
				stopActiveLoopedSoundsExcept()
			end		
			setSoundInActiveLooped(sound)
		end;
		
		[Enum.HumanoidStateType.Jumping] = function()
			if activeState == Enum.HumanoidStateType.Jumping then
				return
			end		

	local ray = Ray.new(Head.Position,Vector3.new(0,-15,0))
			local part1,pos1,norm1,mat1 = workspace:FindPartOnRay(ray,Head.Parent)
		local splashSound = Sounds[SFX.Splash]
			if mat1 and mat1 == Enum.Material.Water then
				splashSound.Volume = .1
				Util.Play(splashSound)
end
			stopActiveLoopedSoundsExcept()
			local sound = Sounds[SFX.Jumping]
			verifyAndSetLoopedForSound(sound,false)
			Util.Play(sound)
		end;
		
		[Enum.HumanoidStateType.GettingUp] = function()
			stopActiveLoopedSoundsExcept()
			local sound = Sounds[SFX.GettingUp]
			verifyAndSetLoopedForSound(sound,false)
			Util.Play(sound)
		end;
		
		[Enum.HumanoidStateType.Freefall] = function()
			if activeState == Enum.HumanoidStateType.Freefall then
				return
			end
			local sound = Sounds[SFX.FreeFalling]
			if sound.Volume ~= 0 then
				sound.Volume = 0
			end
			stopActiveLoopedSoundsExcept()
		end;
		
		[Enum.HumanoidStateType.FallingDown] = function()
			stopActiveLoopedSoundsExcept()
		end;
		
		[Enum.HumanoidStateType.Landed] = function()
			stopActiveLoopedSoundsExcept()
			if Util.VerticalVelocityMagnitude(Head) > 75 then
				local landingSound = Sounds[SFX.Landing]
				landingSound.Volume = Util.Clamp(
					Util.YForLineGivenXAndTwoPts(
						Util.VerticalVelocityMagnitude(Head), 
						50, 0, 
						100, 1),
					0,1)
				Util.Play(landingSound)			
			end
		end
	}
	
	-- Handle state event fired or OnChange fired
	function stateUpdated(state)
		if stateUpdateHandler[state] ~= nil then
			stateUpdateHandler[state]()
		end

		local ray = Ray.new(Head.Position,Vector3.new(0,-15,0))
			local part1,pos1,norm1,mat1 = workspace:FindPartOnRay(ray,Head.Parent)
			if mat1 and mat1 == Enum.Material.Water then
				return
			else
					activeState = state
			end
	end
	
	-- Runs on heartbeat
	function onHeartbeat(step)
		local stepScale = step / (1/60.0)
		
		do
			local sound = Sounds[SFX.FreeFalling]
			if activeState == Enum.HumanoidStateType.Freefall then
				if Head.Velocity.Y < 0 and Util.VerticalVelocityMagnitude(Head) > 75 then
					if not sound.IsPlaying then
						Util.Resume(sound)
					end
					if sound.Volume < 1 then
						sound.Volume = Util.Clamp(sound.Volume + 0.01 * stepScale,0,1)
					end
				else
					if sound.Volume ~= 0 then
						sound.Volume = 0
					end
				end			
			else
				if sound.IsPlaying then
					Util.Pause(sound)
				end
			end
		end
		
		do
			local sound = Sounds[SFX.Running]
			if activeState == Enum.HumanoidStateType.Running then
				if sound.IsPlaying and Util.HorizontalVelocityMagnitude(Head) < 0.5 then
					Util.Pause(sound)
				end
			end
		end		
		
	end
	
	Humanoid.Died:connect(			function() stateUpdated(Enum.HumanoidStateType.Dead) 			end)
	Humanoid.Running:connect(		function() stateUpdated(Enum.HumanoidStateType.Running) 		end)
	Humanoid.Swimming:connect(		function() stateUpdated(Enum.HumanoidStateType.Swimming) 		end)
	Humanoid.Climbing:connect(		function() stateUpdated(Enum.HumanoidStateType.Climbing) 		end)
	Humanoid.Jumping:connect(		function() stateUpdated(Enum.HumanoidStateType.Jumping) 		end)
	Humanoid.GettingUp:connect(	function() stateUpdated(Enum.HumanoidStateType.GettingUp) 	end)
	Humanoid.FreeFalling:connect(	function() stateUpdated(Enum.HumanoidStateType.Freefall) 		end)
	Humanoid.FallingDown:connect(	function() stateUpdated(Enum.HumanoidStateType.FallingDown) 	end)
	
	-- required for proper handling of Landed event
	Humanoid.StateChanged:connect(function(old, new)
		stateUpdated(new)
	end)
	game:GetService('RunService').Heartbeat:connect(onHeartbeat)
end