  The contribution of galactic supernova remnants (SNRs) to the origin of
cosmic rays (CRs) is an important open question in modern astrophysics.
Broadband non-thermal emission is a useful proxy for probing the energy budget
and production history of CRs in SNRs. We conduct hydrodynamic simulations to
model the long-term SNR evolution from explosion all the way to the radiative
phase (or $3\times10^5$ yrs at maximum), and compute the time evolution of the
broadband non-thermal spectrum to explore its potential applications on
constraining the surrounding environments as well as the natures and mass-loss
histories of the SNR progenitors. A parametric survey is performed on the
ambient environments separated into two main groups, namely a homogeneous
medium with a uniform gas density and one with the presence of a circumstellar
structure created by the stellar wind of a massive red-supergiant (RSG)
progenitor star. Our results reveal a highly diverse evolution history of the
non-thermal emission closely correlated to the environmental characteristics of
a SNR. Up to the radiative phase, the roles of CR re-acceleration and
ion-neutral wave damping on the spectral evolution are investigated. Finally,
we make an assessment of the future prospect of SNR observations by the
next-generation hard X-ray space observatory FORCE and predict what we can
learn from their comparison with our evolution models.
