util.AddNetworkString( "HUD_Stamina" )
util.AddNetworkString( "HUD_MaxStamina" )

local defaultRunSpeed = 240
local defaultWalkSpeed = 160

local playerMeta = FindMetaTable("Player")

function playerMeta:SetStamina( amount )
	self.Stamina = math.Clamp(amount, 1, self.MaxStamina)

	net.Start("HUD_Stamina")
		net.WriteUInt(self.Stamina, 8)
	net.Send(self)
end

function playerMeta:SetMaxStamina( amount )
	self.MaxStamina = amount

	net.Start("HUD_MaxStamina")
		net.WriteUInt(self.MaxStamina, 8)
	net.Send(self)
end


hook.Add("PlayerSpawn", "SPRINTING_PlayerSpawn", function(ply)
	ply.RunSpeed = ply.RunSpeed or defaultRunSpeed
	ply.WalkSpeed = ply.WalkSpeed or defaultWalkSpeed

	ply:SetRunSpeed(ply.RunSpeed)
	ply:SetWalkSpeed(ply.WalkSpeed)

	ply:SetMaxStamina( ply.MaxStamina or 100 )
	ply:SetStamina( ply.MaxStamina )

	ply.SprintTime = 0
	ply.Sprinting = false
end)

hook.Add("KeyPress", "SPRINTING_KeyPress", function(ply, key)
	if !ply:Alive() then return end

	if(key == IN_SPEED) then
		if(ply.Stamina > 10) then
			ply:SetRunSpeed(ply.RunSpeed)
		else
			ply:SetRunSpeed(ply.WalkSpeed)
		end
		ply.Sprinting = true
	elseif(key == IN_JUMP and ply:IsOnGround()) then
		if(ply.Stamina < 10) then
			ply:SetJumpPower(0)
		else
			ply:SetJumpPower(200)
			ply:SetStamina(ply.Stamina - 10)
		end
	end
end)

hook.Add("KeyRelease", "SPRINTING_KeyRelease", function(ply, key)
	if(key != IN_SPEED) then return end

	ply.Sprinting = false
end)

local lastTime
hook.Add("Tick", "SPRINTING_Tick", function()
	if lastTime and lastTime > CurTime() then return end

	for k,v in pairs(player.GetAll()) do
		if !v.Sprinting or !(v:KeyDown(IN_FORWARD) or v:KeyDown(IN_BACK) or v:KeyDown(IN_MOVELEFT) or v:KeyDown(IN_MOVERIGHT)) then
			if(v.Stamina < v.MaxStamina) then
				v:SetStamina(v.Stamina + 2)
			end

			continue
		end

		if(v.Stamina <= 0) then
			v:SetRunSpeed(v.WalkSpeed)
			v.Sprinting = false
		else
			v:SetStamina(v.Stamina - 4)
		end
	end

	lastTime = CurTime() + 1
end)