Ignoring any selection rules, how many lines will it have in its emission spectrum?

The number of lines in a spectrum is dependent upon the material being tested. Elements are often the test subject, but (then again) planets and stars have spectra of their own. On an elemental level, a spectrum is based on the number of electron excitation possibilities. More complex structures have much more complex spoectral determinations. Spectral evidence, however, should never be admissible in court!