local mSR = CreateFrame('Frame', 'mortSoulReaper', UIParent)
mSR:RegisterEvent('PLAYER_TARGET_CHANGED')
mSR:SetScript('OnEvent', function(self, event, unit)
    if event == 'UNIT_HEALTH' then
        if unit ~= 'target' then return end
        local health, maxHealth = UnitHealth('target'), UnitHealthMax('target')
        if health > 0 and health / maxHealth <= .25 then
            mSR_Glow('Ferocious Bite')
        else
            mSR_Dim('Ferocious Bite')
        end
    else
        if UnitExists('target') and UnitCanAttack('player', 'target') then
            self:RegisterEvent('UNIT_HEALTH')
            self:GetScript('OnEvent')(self, 'UNIT_HEALTH', 'target')
        else
            mSR_Dim('Ferocious Bite')
            self:UnregisterEvent('UNIT_HEALTH')
        end
    end
end)

function mSR_Glow(spell)
    local bars={'Action','MultiBarBottomLeft','MultiBarBottomRight','MultiBarLeft','MultiBarRight'}
    for bar=1,#bars do
        for button=1,NUM_ACTIONBAR_BUTTONS do
            local buttonName = bars[bar]..'Button'..button
            local mtype, id, _ = GetActionInfo(_G[buttonName].action)
            if mtype == 'macro' then
                local mName, _ = GetMacroSpell(id)
                if mName == spell then
                    ActionButton_ShowOverlayGlow(_G[buttonName])
                    _G[buttonName].glow = true
                end
            elseif mtype == 'spell' then
                local sName, _ = GetSpellInfo(id)
                if sName == spell then
                    ActionButton_ShowOverlayGlow(_G[buttonName])
                end
            end
        end
    end
end

function mSR_Dim(spell)
    local bars={'Action','MultiBarBottomLeft','MultiBarBottomRight','MultiBarLeft','MultiBarRight'}
    for bar=1,#bars do
        for button=1,NUM_ACTIONBAR_BUTTONS do
            local buttonName = bars[bar]..'Button'..button
            local mtype, id, _ = GetActionInfo(_G[buttonName].action)
            if mtype == 'macro' then
                local mName, _ = GetMacroSpell(id)
                if mName == spell then
                    ActionButton_HideOverlayGlow(_G[buttonName])
                end
            elseif mtype == 'spell' then
                local sName, _ = GetSpellInfo(id)
                if sName == spell then
                    ActionButton_HideOverlayGlow(_G[buttonName])
                end
            end
        end
    end
end