Generating random values from a customized distribution

I have this distribution below:

using Distributions
struct OrthoNNDist <: DiscreteMultivariateDistribution
    x0::Vector{Int64}
    oc::Array{Int64,2}
    x1s::Array
    prob::Float64
    #return a new uniform distribution with all vectors in x1s orthogonal to oc
    function OrthoNNDist(x0::Vector{Int}, oc::Array{Int,2})
        x1s = []
        for i = 1:size(oc)[2]
            x1 = x0 + oc[:, i]
            if nonneg(x1)
                push!(x1s, x1)
            end
            x1 = x0 - oc[:, i]
            if nonneg(x1)
                push!(x1s, x1)
            end
        end
        new(x0, oc, x1s, 1.0/length(x1s))
    end
end

Base.length(d::OrthoNNDist) = length(d.x0)

Distributions.rand(d::OrthoNNDist, N::Integer=1) = rand(d.x1s, 1)

Distributions.pdf(d::OrthoNNDist, x::Vector) = x in d.x1s? D.prob: 0.0
Distributions.pdf(d::OrthoNNDist) = fill(d.prob, size(d.x1s))
Distributions.logpdf(d::OrthoNNDist, x::Vector) = log(PDF(d, x))

and I want to generate random values from it, I don't know how I've tried:rand(OrthoNNDist,1000)and it didn't work, I'm kinda new on probabilistic programming, I don't know how I can do that.