configure

#!/bin/sh

R_HOME=$(R RHOME)

# Function to detect BLAS library
detect_blas() {
    blas_info=$(${R_HOME}/bin/R --slave -e "si <- sessionInfo(); cat(si\$BLAS, '\n', si\$LAPACK)")
    if echo "$blas_info" | grep -iq "mkl"; then
        echo "mkl"
    elif echo "$blas_info" | grep -iq "openblas"; then
        echo "openblas"
    else
        echo "default"
    fi
}

# Detect BLAS
BLAS_TYPE=$(detect_blas)

# OPENBLAS seems sub-optimal
case $BLAS_TYPE in
    mkl)
        echo "Using MKL"
        BLAS_LAPACK_LIBS="-lmkl_rt"
        USE_MKL=true
        USE_OPENBLAS=false
        USE_LAPACKE=true
        ;;
    *)
        echo "Using default BLAS and LAPACK"
        BLAS_LAPACK_LIBS="-lblas -llapack"
        USE_MKL=false
        USE_OPENBLAS=false
        USE_LAPACKE=false
        ;;
esac

# Create Makevars
sed -e "s|@BLAS_LAPACK_LIBS@|$BLAS_LAPACK_LIBS|" \
    -e "s|@USE_MKL@|$USE_MKL|" \
    -e "s|@USE_OPENBLAS@|$USE_OPENBLAS|" \
    -e "s|@USE_LAPACKE@|$USE_LAPACKE|" \
    src/Makevars.in > src/Makevars