#! /bin/bash

################################################################################
# Prepare
################################################################################

# Set up shell
set -x                          # Output commands
set -e                          # Abort on errors



################################################################################
# Search
################################################################################

if [ -z "${ZLIB_DIR}" ]; then
    echo "BEGIN MESSAGE"
    echo "zlib selected, but ZLIB_DIR not set. Checking some places..."
    echo "END MESSAGE"
    
    FILES="include/zlib.h lib/libz.a"
    DIRS="/usr /usr/local /usr/local/zlib /usr/local/packages/zlib /usr/local/apps/zlib /opt/local ${HOME} ${HOME}/zlib c:/packages/zlib"
    for dir in $DIRS; do
        ZLIB_DIR="$dir"
        for file in $FILES; do
            if [ ! -r "$dir/$file" ]; then
                unset ZLIB_DIR
                break
            fi
        done
        if [ -n "$ZLIB_DIR" ]; then
            break
        fi
    done
    
    if [ -z "$ZLIB_DIR" ]; then
        echo "BEGIN MESSAGE"
        echo "zlib not found"
        echo "END MESSAGE"
    else
        echo "BEGIN MESSAGE"
        echo "Found zlib in ${ZLIB_DIR}"
        echo "END MESSAGE"
    fi
fi



################################################################################
# Build
################################################################################

if [ -z "${ZLIB_DIR}" -o "${ZLIB_DIR}" = 'BUILD' ]; then
    echo "BEGIN MESSAGE"
    echo "Building zlib..."
    echo "END MESSAGE"
    
    # Set locations
    THORN=zlib
    NAME=zlib-1.2.5
    SRCDIR=$(dirname $0)
    BUILD_DIR=${SCRATCH_BUILD}/build/${THORN}
    if [ -z "${ZLIB_INSTALL_DIR}" ]; then
        echo "BEGIN MESSAGE"
        echo "ZLIB install directory, ZLIB_INSTALL_DIR, not set. Installing in the default configuration location. "
        echo "END MESSAGE"
     INSTALL_DIR=${SCRATCH_BUILD}/external/${THORN}
    else
        echo "BEGIN MESSAGE"
        echo "ZLIB install directory, ZLIB_INSTALL_DIR, selected. Installing ZLIB at ${ZLIB_INSTALL_DIR} "
        echo "END MESSAGE"
     INSTALL_DIR=${ZLIB_INSTALL_DIR}
    fi
    DONE_FILE=${SCRATCH_BUILD}/done/${THORN}
    ZLIB_DIR=${INSTALL_DIR}
    
(
    exec >&2                    # Redirect stdout to stderr
    set -x                      # Output commands
    set -e                      # Abort on errors
    cd ${SCRATCH_BUILD}
    if [ -e ${DONE_FILE} -a ${DONE_FILE} -nt ${SRCDIR}/dist/${NAME}.tar.gz \
                         -a ${DONE_FILE} -nt ${SRCDIR}/zlib.sh ]
    then
        echo "zlib: The enclosed zlib library has already been built; doing nothing"
    else
        echo "zlib: Building enclosed zlib library"
        
        # Should we use gmake or make?
        MAKE=$(gmake --help > /dev/null 2>&1 && echo gmake || echo make)
        # Should we use gtar or tar?
        TAR=$(gtar --help > /dev/null 2> /dev/null && echo gtar || echo tar)
        # Should we use gpatch or patch?
        if [ -z "$PATCH" ]; then
            PATCH=$(gpatch -v > /dev/null 2>&1 && echo gpatch || echo patch)
        fi
        
        # Set up environment
        export LDFLAGS
        unset LIBS
        if echo '' ${ARFLAGS} | grep 64 > /dev/null 2>&1; then
            export OBJECT_MODE=64
        fi
        # Disable parallel make. With parallel make, I sometimes
        # encounter a build error "ld: in libz.a, malformed archive
        # TOC entry for _zlibVersion, offset 824872 is beyond end of
        # file 237568 for architecture x86_64"
        unset MAKEFLAGS
        
        echo "zlib: Preparing directory structure..."
        mkdir build external done 2> /dev/null || true
        rm -rf ${BUILD_DIR} ${INSTALL_DIR}
        mkdir ${BUILD_DIR} ${INSTALL_DIR}
        
        echo "zlib: Unpacking archive..."
        pushd ${BUILD_DIR}
        ${TAR} xzf ${SRCDIR}/dist/${NAME}.tar.gz
        ${PATCH} -p0 < ${SRCDIR}/dist/install.diff
        
        echo "zlib: Configuring..."
        cd ${NAME}
        # Guess whether Cactus uses static linking, and if so, build
        # only static libraries
        ./configure --prefix=${ZLIB_DIR} $(if echo '' ${LDFLAGS} | grep -q static; then echo '' '--static'; fi)
        
        echo "zlib: Building..."
        ${MAKE}
        
        echo "zlib: Installing..."
        ${MAKE} install prefix=${ZLIB_DIR}
        popd
        
        echo "zlib: Cleaning up..."
        rm -rf ${BUILD_DIR}
        
        date > ${DONE_FILE}
        echo "zlib: Done."
    fi
)

    if (( $? )); then
        echo 'BEGIN ERROR'
        echo 'Error while building zlib. Aborting.'
        echo 'END ERROR'
        exit 1
    fi
    
fi



################################################################################
# Check for additional libraries
################################################################################

# Set options
if [ "${ZLIB_DIR}" = '/usr' -o "${ZLIB_DIR}" = '/usr/local' ]; then
    ZLIB_INC_DIRS=''
    ZLIB_LIB_DIRS=''
else
    ZLIB_INC_DIRS="${ZLIB_DIR}/include"
    ZLIB_LIB_DIRS="${ZLIB_DIR}/lib"
fi
ZLIB_LIBS='z'



################################################################################
# Configure Cactus
################################################################################

# Pass options to Cactus
echo "BEGIN MAKE_DEFINITION"
echo "HAVE_ZLIB     = 1"
echo "ZLIB_DIR      = ${ZLIB_DIR}"
echo "ZLIB_INC_DIRS = ${ZLIB_INC_DIRS}"
echo "ZLIB_LIB_DIRS = ${ZLIB_LIB_DIRS}"
echo "ZLIB_LIBS     = ${ZLIB_LIBS}"
echo "END MAKE_DEFINITION"

echo 'INCLUDE_DIRECTORY $(ZLIB_INC_DIRS)'
echo 'LIBRARY_DIRECTORY $(ZLIB_LIB_DIRS)'
echo 'LIBRARY           $(ZLIB_LIBS)'