func addOptions(q rdb.Term, value string, index string, opts *t.BrowseOpt) rdb.Term {
var limit uint = 1024 // TODO(gene): pass into adapter as a config param
var lower, upper interface{}
if opts != nil {
if opts.Since > 0 {
lower = opts.Since
} else {
lower = rdb.MinVal
}
if opts.Before > 0 {
upper = opts.Before
} else {
upper = rdb.MaxVal
}
if value != "" {
lower = []interface{}{value, lower}
upper = []interface{}{value, upper}
}
if opts.Limit > 0 && opts.Limit < limit {
limit = opts.Limit
}
} else {
lower = []interface{}{value, rdb.MinVal}
upper = []interface{}{value, rdb.MaxVal}
}
return q.Between(lower, upper, rdb.BetweenOpts{Index: index}).
OrderBy(rdb.OrderByOpts{Index: rdb.Desc(index)}).Limit(limit)
}
