#! /usr/bin/env bash
#
# This script builds Zeek, then creates a tar file of the Zeek installation which
# will be used by each zeekctl test case to have its own fresh install of Zeek.
# This script must be run before attempting to run any of the zeekctl tests.
#
# Usage:  build-zeek [--clean]
#
# If the "--clean" parameter is specified, then this script just removes
# the zeekctl test install directory and tar file.
#
# A user can modify the behavior of this script by setting any of these
# env. variables:
#   ZEEKCTL_TEST_USEBUILD  - If this is set (value doesn't matter), then Zeek
#                           will be built in the default Zeek build directory
#                           instead of using a new directory.  This is intended
#                           to be used when Zeek was previously built, to
#                           shorten the time it takes to do the rebuild.
#   ZEEKCTL_TEST_BUILDARGS - Specify additional options that will be passed
#                           to Zeek's "configure" script.


# This function builds Zeek using a build directory specifically for zeekctl
# tests (if ZEEKCTL_TEST_USEBUILD is defined, then the default Zeek build
# directory is used instead).
build_zeek() {
    cd "${ZEEKSRCDIR}"

    ccache_arg=""
    if command -v ccache; then
        ccache_arg="--ccache"
    fi

    if [ -n "${ZEEKCTL_TEST_USEBUILD}" ]; then
        # Reuse a previous build in the default Zeek build directory.
        BUILDPREFIX=build
        # Rebuild using a new prefix (use ZEEKCTL_TEST_BUILDARGS to
        # specify any other flags that were used for the previous
        # build). Also specify a libdir so we know we're using "lib"
        # as our library prefix -- it's used throughout the testsuite.
        ./configure --prefix="${INSTALLPREFIX}" --libdir="${INSTALLPREFIX}/lib" \
                    ${ZEEKCTL_TEST_BUILDARGS} ${ccache_arg}
    else
        # Use a build directory specifically for zeekctl tests.
        BUILDPREFIX=${ZEEKCTLBUILDDIR}/zeek-build
        # Additional configure options are used here to reduce the build size.
        ./configure --builddir=${BUILDPREFIX} --prefix="${INSTALLPREFIX}" \
                    --libdir="${INSTALLPREFIX}/lib" --build-type=Release \
		    --disable-broker-tests \
                    --disable-auxtools ${ZEEKCTL_TEST_BUILDARGS} ${ccache_arg}
    fi

    test $? -ne 0 && return 1

    ncpus=2
    if [ -n "${ZEEK_CI_CPUS}" ]; then
        ncpus=${ZEEK_CI_CPUS}
    elif type nproc >/dev/null 2>&1; then
        ncpus=$(nproc)
    fi

    echo "Building Zeek with ${ncpus} processors ..."

    cd ${BUILDPREFIX} && make -j ${ncpus} install
}

# Replace the Zeek install prefix directory path with the text "@PREFIX@".  This
# is needed so that each ZeekControl test script can use its own install prefix.
replaceprefix() {
    # First, fix the ZEEKSCRIPTDIR path (this step is needed to avoid any
    # unintended difference between ZEEKSCRIPTDIR and INSTALLPREFIX because on
    # FreeBSD /home is actually a symlink to /usr/home).
    #
    # To locate Python files in the installed tree, rely on the
    # installation's zeek-config to avoid hardwiring paths:
    pydir="$($INSTALLPREFIX/bin/zeek-config --python_dir)"

    oldpath=`grep '^ZEEKSCRIPTDIR' $pydir/zeekctl/ZeekControl/version.py | awk -F \" '{ print $2 }'`
    newpath=`realpath "$oldpath"`
    if [ "$newpath" != "$oldpath" ]; then
        for i in $pydir/zeekctl/ZeekControl/version.py ; do
            sed "s#$oldpath#$newpath#" $i > $i.new && cp $i.new $i && rm $i.new
        done
    fi

    for i in etc/zeekctl.cfg bin/zeekctl bin/zeek-config $pydir/zeekctl/ZeekControl/version.py ; do
        sed "s#${INSTALLPREFIX}#@PREFIX@#" $i > $i.new && cp $i.new $i && rm $i.new
        if [ $? -ne 0 ]; then
            return 1
        fi
    done
}

# Remove the tar file and all test-specific Zeek installation directories.
clean() {
    definevars

    # Verify the path is a directory (and exists) before attempting to
    # remove.
    test -d "${ZEEKCTL_TEST}" && rm -rf "${ZEEKCTL_TEST}"

    # If the directory still exists, then something is wrong.
    if [ -d "${ZEEKCTL_TEST}" ]; then
        exit 1
    fi

    exit 0
}


definevars() {
    # Path to the top-level ZeekControl source code directory.
    ZEEKCTLSRCDIR=`dirname "$0"`/../..

    # Path to the Zeek source code directory.
    ZEEKSRCDIR=${ZEEKCTLSRCDIR}/../..

    # Path to the ZeekControl "build" directory.
    ZEEKCTLBUILDDIR=`realpath "${ZEEKCTLSRCDIR}/build"`

    # Absolute path of parent directory where Zeek will be installed.
    ZEEKCTL_TEST=${ZEEKCTLBUILDDIR}/testing
    test -z "${ZEEKCTL_TEST}" && exit 1
}


# Create a tar file of the Zeek installation.  The tar file will be used by
# each zeekctl test script to create a test-specific Zeek installation.
create_tar() {
    definevars

    # Exit if any command fails.
    set -e

    # Verify that the entire Zeek git repo was cloned (not just the zeekctl repo).
    if [ ! -e "${ZEEKSRCDIR}/configure" ]; then
        echo "Error: in order to run the ZeekControl tests, you must clone the zeek repo (not just the zeekctl repo)" 1>&2
        exit 1
    fi

    # Remove the test directory if it exists.
    if [ -e "${ZEEKCTL_TEST}" ]; then
        rm -rf "${ZEEKCTL_TEST}"
    fi

    mkdir -p ${ZEEKCTL_TEST}

    # The tar file that all zeekctl test cases will use.
    TARFILE=${ZEEKCTL_TEST}/zeek-test-install.tar

    LOG=${ZEEKCTLBUILDDIR}/buildzeek.log
    rm -f "$LOG"

    # Zeek will be installed in this temporary directory.
    INSTALLPREFIX=${ZEEKCTL_TEST}/zeek-install

    # Don't exit if a command fails.
    set +e

    # Build and install Zeek in the temporary directory.
    if [ -n "${CI}" ]; then
        # Show build output in CI
        build_zeek
        if [ $? -ne 0 ]; then
            echo "Error: Zeek build failed" 1>&2
            exit 1
        fi
    else
        echo "Building Zeek (log in $LOG) ..."
        build_zeek >>$LOG 2>&1
        if [ $? -ne 0 ]; then
            echo "Error: Zeek build failed:" 1>&2
            tail -n 20 $LOG 1>&2
            exit 1
        fi
    fi

    # Create a tar file of the installation so each test case can start with a
    # clean installation without needing to rebuild Zeek.
    (cd "${INSTALLPREFIX}" && replaceprefix && tar cf "${TARFILE}" * )
    if [ $? -ne 0 ]; then
        rm -rf "${INSTALLPREFIX}"
        exit 1
    fi
}

if [ "$1" = "--clean" ]; then
    clean
else
    create_tar
fi