#!/bin/sh

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

set -e

# Read configuration variable file if it is present
[ -r /etc/default/koha-common ] && . /etc/default/koha-common

# include helper functions
if [ -f "/usr/share/koha/bin/koha-functions.sh" ]; then
    . "/usr/share/koha/bin/koha-functions.sh"
else
    echo "Error: /usr/share/koha/bin/koha-functions.sh not present." 1>&2
    exit 1
fi

usage()
{
    local scriptname=$0
    cat <<EOF
Manage Elasticsearch-related tasks for Koha instances

Usage: $scriptname [actions] [options] instancename1 instancename2...

Actions:
    --rebuild         Trigger a rebuild process

Options:
    --delete|-d       Delete elasticsearch index before reindexing.
    --reset|-r        Reset elasticsearch mappings from file.
    --authorities|-a  Only run process for authorities.
    --biblios|-b      Only run process for biblios.
    -c|--commit n     Specify how many records will be batched up before
                      they're added to Elasticsearch (default: 5000).
    -p|--processes n  Specify the number of parallel processes to use
                      for indexing.
    -w|--where SQL    Pass some additional SQL to limit the records to
                      be indexed.

    --verbose|-v      Be verbose.
    --help|-h         Print this help.

EOF
}

toggle_biblios_only()
{
    biblios_only="yes"
    biblios="yes"
    if [ "${authorities_only}" != "yes" ]; then
        authorities="no"
    fi
}

toggle_authorities_only()
{
    authorities_only="yes"
    authorities="yes"
    if [ "${biblios_only}" != "yes" ]; then
        biblios="no"
    fi
}

set_action()
{
    if [ "${op}" = "" ]; then
        op=$1
    else
        die "Error: only one action can be specified."
    fi
}

run_rebuild_elasticsearch()
{
    # read instance name and eliminate instance name from params
    local name=$1; shift

    if [ "${clo_commit_size}" -gt 0 ] 2>/dev/null; then
        commit_size=${clo_commit_size}
    fi
    rebuild_opts="--commit ${commit_size}"

    if [ "${clo_processes}" -gt 0 ] 2>/dev/null; then
        processes=${clo_processes}
    fi
    rebuild_opts="${rebuild_opts} --processes ${processes}"

    if [ "${delete}" = "yes" ]; then
        rebuild_opts="${rebuild_opts} -d"
    fi

    if [ "${reset}" = "yes" ]; then
        rebuild_opts="${rebuild_opts} -r"
    fi

    if [ "${biblios}" = "yes" ]; then
        rebuild_opts="${rebuild_opts} -b"
    fi

    if [ "${authorities}" = "yes" ]; then
        rebuild_opts="${rebuild_opts} -a"
    fi

    if [ "${verbose}" = "yes" ]; then
        rebuild_opts="${rebuild_opts} -v"
    fi

    if [ "${where}" ]; then
        rebuild_opts="${rebuild_opts} --where \"${where}\""
    fi

    # KOHA_HOME and KOHA_BINDIR may have been adjusted/set by adjust_paths_git_install
    if koha-shell \
          -c "${KOHA_HOME}/${KOHA_BINDIR}/search_tools/rebuild_elasticsearch.pl ${rebuild_opts}" \
          ${name}; then
        return 0
    else
        return 1
    fi
}

# Default parameters from koha-common.default
biblios=$ES_INDEX_BIBLIOS         # the 'only' variants are skipped because they don't actually control
authorities=$ES_INDEX_AUTHORITIES # anything and are just for setting stuff internally.
commit_size=$ES_COMMIT_SIZE
processes=$ES_NUMBER_OF_PROCESSES
verbose=$ES_VERBOSE
where=$ES_WHERE_QUERY_SQL

# Default parameters if all else fails
: ${biblios:="yes"}
: ${authorities:="yes"}
: ${commit_size:=5000}
: ${processes:=1}
: ${verbose:="no"}
: ${where:=""}

biblios_only="no"
authorities_only="no"
op=""

# Read parameters
while [ -n "$*" ]; do
    case "$1" in
        -h|--help)
            usage ; exit 0
            ;;
        -d|--delete)
            delete="yes"
            ;;
        -r|--reset)
            reset="yes"
            ;;
        -b|--biblios)
            toggle_biblios_only
            ;;
        -a|--authorities)
            toggle_authorities_only
            ;;
        -c|--commit)
            clo_commit_size="$2" ; shift
            ;;
        -p|--processes)
            clo_processes="$2" ; shift
            ;;
        -w|--where)
            where="$2" ; shift
            ;;
        --rebuild)
            set_action "rebuild"
            ;;
        -v|--verbose)
            verbose="yes"
            ;;
        *)
            break
            ;;
    esac

    shift
done

# Parse command line.
if [ $# -lt 1 ]; then
    usage
    die "Missing instance name."
fi

# Loop over instance names
for name in "$@"
do
    if is_instance $name; then
        adjust_paths_git_install $name
        if [ "${op}" = "rebuild" ]; then
            if ! run_rebuild_elasticsearch $name; then
                warn "Something went wrong rebuilding indexes for ${name}"
            fi
        else
            # TODO: Add other actions, status? etc
            usage
            die "Error: no action passed"
        fi
    else
        warn "Unknown instance ${name}"
    fi
done

exit 0