  Recently, a hydrogen-poor superluminous supernova (SLSN) iPTF15esb at
redshift $z=0.224$ was reported, whose light curve (LC) and spectrum show
several unusual characteristics. Its late-time spectrum shows a strong, broad
H$\alpha $ emission line and the bolometric LC exhibits two peaks and a
post-peak plateau. Here we propose an ejecta-circumstellar medium (CSM)
interaction model involving multiple shells and winds to explain this
double-peak SN. We find that the theoretical LC reproduced by this model can
well match the observations of iPTF15esb. Based on this result, we infer that
the progenitor has undergone at least three violent mass-loss processes before
the SN explosion. Furthermore, we find that the masses of the CSM wind and
shells from the outermost shell (the first eruption) to the innermost wind (the
final eruption) decrease sequentially but their densities increase. The
variation trend of the inferred densities of the shells and wind is consistent
with the stellar structure before an SN explosion. Further investigations for
similar SLSNe would provide a probe for the mass-loss history of their
progenitors.
