Switch to auto mode and follow mission

ArduPlane
1

Hey! I’m a total newbie and I want to receive a mission and follow it. In order to do this, I started writing the following code in Lua:

function update()
    local item = mission:get_item(0)
    if not item then
        gcs:send_text(6, "No waypoint loaded.")
        return update, 3000
    end

    gcs:send_text(6, string.format("Waypoint 0: lat=%.6f, lon=%.6f, alt=%.2f",
    item.x, item.y, item.z))

    local mode = vehicle:get_mode()
    if mode ~= 10 then  
        gcs:send_text(6, "Switching to AUTO.MISSION...")
        vehicle:set_mode(10)
    else
        gcs:send_text(6, "Already in AUTO.MISSION.")
    end

    return update, 5000
end

return update()

I can’t find the auto mode ID anywhere (ArduPlane). It seems like it’s trying to get to it’s own location, which isn’t my goal.

Any help is appreciated.