###
### "THE BEER-WARE LICENSE":
### Alberto Ramos wrote this file. As long as you retain this 
### notice you can do whatever you want with this stuff. If we meet some 
### day, and you think this stuff is worth it, you can buy me a beer in 
### return. <alberto.ramos@cern.ch>
###
### file:    ScalarFields.jl
### created: Mon Oct 11 21:18:26 2021
###                               

function randomize!(f, sp::ScalarParm{NS}, lp::SpaceParm, ymws::YMworkspace) where {NS}
    
    @timeit "Randomize scalar field" begin
        m = CUDA.randn(ymws.PRC, lp.bsz, 4, NS, lp.rsz)
        CUDA.@sync begin
            CUDA.@cuda threads=lp.bsz blocks=lp.rsz krnl_assign_SU2fund!(f,m,sp,lp)
        end
    end

    return nothing
end

function krnl_assign_SU2fund!(f::AbstractArray{T}, m, sp::ScalarParm{NS}, lp::SpaceParm) where {T, NS}

    # Think about precision here
    SR2 = 1.4142135623730951
    
    b, r = CUDA.threadIdx().x, CUDA.blockIdx().x
    for i in 1:NS
        f[b,i,r] = SU2fund(complex(m[b,1,i,r]*SR2, m[b,2,i,r]*SR2),
                           complex(m[b,3,i,r]*SR2, m[b,4,i,r]*SR2))
    end

    return nothing
end