function OBWT_OnLoad()
	this:RegisterEvent('PLAYER_ENTERING_WORLD')
	this:RegisterEvent('ADDON_LOADED')
	DEFAULT_CHAT_FRAME:AddMessage('One button warrior tanking. Type /obwt for usage.')
	SlashCmdList['OBWT'] = function()
		local msg = 'To use OBWT addon, create a macro and type /script obwt();'
		DEFAULT_CHAT_FRAME:AddMessage(msg)
	end;
	SLASH_OBWT1 = '/obwt'
end

function obwt()
	local rage = UnitMana('player')
	local bloodthirst = 'Ability_Warrior_Bloodthirst'
	local revenge = 'Ability_Warrior_Revenge'
	local sunderArmor = 'Ability_Warrior_SunderArmor'
	local rend = 'Ability_Warrior_Rend'
	local battleShout = 'Ability_Warrior_BattleShout'
	local heroicStrike = 'Ability_Warrior_HeroicStrike'

	TargetNearestEnemy()
	if UnitExists('target') and UnitCanAttack('player','target') then
		AttackTarget()
		if rage < 15 == nil and isUsable(bloodthirst) then
			CastSpellByName('Bloodthirst')
		elseif buffed('Battle Shout') == nil and isUsable(battleShout) then
			CastSpellByName('Battle Shout')
		elseif isUsable(revenge) then
			CastSpellByName('Revange')
		elseif isUsable(sunderArmor) then
			CastSpellByName('Sunder Armor')
		elseif rage > 50 and buffed('Rend', 'target') == nil and isUsable(rend) then
			CastSpellByName('Rend')
		elseif rage > 70 and isUsable(heroicStrike) then
			CastSpellByName('Heroic Strike')
		end
	end

local function isUsable(spellTexture)
	return IsUsableAction(getSlot(spellTexture))
end

local function getSlot(spellTexture)
	for i = 1, 120, 1
		do
		if(GetActionTexture(i) ~= nil) then 
			if(strfind(GetActionTexture(i), spellTexture)) then return i end
		end
	end
	return 0
end;