slowmo_flag = false
drug_flag = false
function on_game_start()
    RegisterScriptCallback("on_key_press", on_key_press)
    RegisterScriptCallback("actor_on_update", power_drain_check)
    RegisterScriptCallback("actor_on_before_death", actor_on_before_death)
    RegisterScriptCallback("on_game_load", on_game_load)
    RegisterScriptCallback("actor_on_item_use", drug_module)
end

function slowmo_on()
    local slowmo_snd_on = sound_object("slow-mo\\slowmo_on")
    slowmo_snd_on:play_at_pos(actor, vector():set(0, 0, 0), 0, sound_object.s2d)
    level.add_pp_effector("blink.ppe", 2004, false)
    level.set_pp_effector_factor(2004, 0.2) -- here you can change the brightness of the effect (second value, 0-1)
    get_console():execute("time_factor 0.5")
    slowmo_flag = true
end

function slowmo_off()
    local slowmo_snd_off = sound_object("slow-mo\\slowmo_off")
    slowmo_snd_off:play_at_pos(actor, vector():set(0, 0, 0), 0, sound_object.s2d)
    level.add_pp_effector("blink.ppe", 2004, false)
    level.set_pp_effector_factor(2004, 0.2) -- here you can change the brightness of the effect (second value, 0-1)
    get_console():execute("time_factor 1")
    slowmo_flag = false
end

function actor_on_before_death()
    slowmo_off()
end

function on_game_load()
    get_console():execute("time_factor 1")
end

function on_key_press(key)
    if not db.actor:alive() then
        return
    end

    -- here you can change slow-mo key
    if (key == DIK_keys["DIK_V"]) then
        if not slowmo_flag then
            slowmo_on()
        elseif slowmo_flag then
            slowmo_off()
        end
    end
end

function power_drain_check()
    if not drug_flag then
        if (db.actor.power > 0.1 and slowmo_flag) then
            db.actor:change_power(-0.001) -- here you can adjust stamina drain
        elseif (db.actor.power < 0.1 and slowmo_flag) then
            slowmo_off()
        end
    end
end

function drug_module(item)
    local section = item:section()
    local drug_tbl = {
        ["adrenalin"] = true,
        ["cocaine"] = true
    }
    if drug_tbl[section] then
        CreateTimeEvent(0, "drug_on", 5, drug_on)
    end
end

function drug_on()
    xr_effects.play_snd(db.actor, nil, {[1] = "slow-mo\\adrenalin"})
    CreateTimeEvent(0, "adrenalin_off", 20, drug_off)
    drug_flag = true
    slowmo_on()
    return true
end

function drug_off()
    slowmo_off()
    drug_flag = false
    return true
end