This is a rare mini 998 LS. The 998 LS was introduced as the successor to the mini S and SS, and was considered a top spec model. The 998 LS in some ways was more equipped than the 1275 LS, with items such as grille mounted foglights standard (whilst these features were optional on the 1275 LS.
This car is the most common colour you will find the 998 LS in - metallic blue. Often, these came with a vinyl roof (usually dark blue originally to give a 2 tone effect). However, these days, unless you find one restored to original specifications, 998 LS cars have usually been painted all over, or simply have the roof painted the darker blue rather than the vinyl covering.
A comprehensive identification guide for the 998LS can be found here: http://classicregister.com/content/how-identify-1977-1978-leyland-mini-998-ls