# This script will query 'pkg-config' for the required cflags and ldflags.
# If pkg-config is unavailable or does not find the library, try setting
# INCLUDE_DIR and LIB_DIR manually via e.g:
# R CMD INSTALL --configure-vars='INCLUDE_DIR=/.../include LIB_DIR=/.../lib'

# Library settings
PKG_CONFIG_NAME="libuv"
PKG_DEB_NAME="libuv1-dev"
PKG_RPM_NAME="libuv-devel"
PKG_BREW_NAME="libuv"
PKG_TEST_HEADER="<uv.h>"
PKG_LIBS="-luv"

# Use pkg-config if available
if [ `command -v pkg-config` ]; then
  PKGCONFIG_CFLAGS=`pkg-config --cflags --silence-errors ${PKG_CONFIG_NAME}`
  PKGCONFIG_LIBS=`pkg-config --libs ${PKG_CONFIG_NAME}`
fi

# Note that cflags may be empty in case of success
if [ "$PKGCONFIG_CFLAGS" ] || [ "$PKGCONFIG_LIBS" ]; then
  echo "Found pkg-config cflags and libs!"
  PKG_CFLAGS=${PKGCONFIG_CFLAGS}
  PKG_LIBS=${PKGCONFIG_LIBS}
elif [ "$(uname)" = "Darwin" ] && [ -z "$USE_BUNDLED_LIBUV" ]; then
  curl -sfL "https://autobrew.github.io/scripts/$PKG_BREW_NAME" > autobrew
  . ./autobrew
elif test -f "/etc/redhat-release" && ! grep -Fq Fedora "/etc/redhat-release"; then
  # RHEL 8/9 does not have libuv
  USE_BUNDLED_LIBUV=true
fi

if [ "$USE_BUNDLED_LIBUV" ]; then
  echo "Building static libuv" 1>&2
  cp -f src/Makevars.vendor src/Makevars
  exit 0
fi

# For debugging
echo "Using PKG_CFLAGS=$PKG_CFLAGS"
echo "Using PKG_LIBS=$PKG_LIBS"

# Find compiler
CC=`${R_HOME}/bin/R CMD config CC`
CFLAGS=`${R_HOME}/bin/R CMD config CFLAGS`
CPPFLAGS=`${R_HOME}/bin/R CMD config CPPFLAGS`

# Test configuration
echo "#include $PKG_TEST_HEADER" | ${CC} ${CPPFLAGS} ${PKG_CFLAGS} ${CFLAGS} -E -xc - >/dev/null 2>configure.log

# Customize the error
if [ $? -ne 0 ]; then
  echo "--------------------------- [CONFIGURE] --------------------------------"
  echo "Configuration failed because $PKG_CONFIG_NAME was not found. Try installing:"
  echo " * deb: $PKG_DEB_NAME (Debian, Ubuntu, etc)"
  echo " * rpm: $PKG_RPM_NAME (Fedora, EPEL)"
  echo " * brew: $PKG_BREW_NAME (OSX)"
  echo "Alternatively set environment variable USE_BUNDLED_LIBUV=1 to build a static"
  echo "version of libuv that is included with this package."
  echo "-------------------------- [ERROR MESSAGE] ---------------------------"
  cat configure.log
  echo "--------------------------------------------------------------------"
  exit 1
fi

# Write to Makevars
sed -e "s|@cflags@|$PKG_CFLAGS|" -e "s|@libs@|$PKG_LIBS|" src/Makevars.in > src/Makevars

# Success
exit 0
