We use a single-channel scattering formalism to derive general expressions for the Andreev bound-state energies and resulting current--phase relationship in a one-dimensional semiconductor-based SNS-junction, including arbitrarily oriented effective spin--orbit and Zeeman fields and taking into account disorder in the junction in by including a single scatterer with transmission probability $0 \leq T^2 \leq 1$, arbitrarily located in the normal region. We first corroborate our results by comparing them to the known analytic limiting-case expressions. Then we simplify our general result in several additional limits, including the case of the scatterer being at a specific location and the cases of small and large spin--orbit fields compared to the Zeeman splitting, assuming low transparency ($T\ll 1$). We believe that our results could be helpful for disentangling the main spin-mixing processes in experiments on low-dimensional semiconductor-based SNS-junctions.
