#!/bin/bash
set -eu

# copy_diff_files
copy_diff_files(){
  if [[ ! -f $2 ]] ; then
    cp "$1" "$2"
  else
  if [[ "$(diff "$1" "$2")" != "" ]] ; then
    cp "$1" "$2"
  else
    echo "confirmed $2"
  fi
  fi
}

CONF_FILES=( conf/configure.nmmb.* )
CONF=()

for f in "${CONF_FILES[@]}"; do
    name=$(basename "$f")
    CONF+=( ${name#configure.nmmb.} )
done

usage() {
    echo
    echo "Usage: $0 <configuration>"
    echo
    echo " where <configuration> is one of:"
    echo
    for f in "${CONF[@]}"; do
        echo "  $f"
    done
    echo
    exit 1
}

if [[ $# -eq 0 ]]; then
    CONFIGNAME=""
    while [[ "$CONFIGNAME" == "" ]]; do
        echo "Please enter the number of the configuration you want to select:"
        select CONFIGNAME in "${CONF[@]}"; do
            if [[ $CONFIGNAME = "" ]]; then
                 echo
                 echo "Please enter a valid number. Retry."
            fi
            break
        done
    done
    CONFIGURATION=$CONFIGNAME
elif [[ $# -eq 1 && "$1" == "-h" ]]; then
    usage
elif [[ $# -gt 1 ]]; then
    usage
elif [[ $# -eq 1 && "$1" == "clean" ]]; then
    rm -f conf/configure.nmmb
    rm -f conf/modules.nmmb
    exit
else
    if [[ "${CONF[@]}" =~ ${1} ]]; then
        CONFIGURATION=${1}
    else
        echo
        echo "No such configuration. The configuration option \"${1}\" is invalid."
        usage
    fi
fi

CONFIGURE_FILE=conf/configure.nmmb.$CONFIGURATION
MODULES_FILE=conf/modules.nmmb.$CONFIGURATION

[[ ! -f "$CONFIGURE_FILE" ]] && usage
copy_diff_files "$CONFIGURE_FILE" conf/configure.nmmb

[[ -f "$MODULES_FILE" ]] && copy_diff_files "$MODULES_FILE" conf/modules.nmmb

echo
echo "The NMMB is now configured on $CONFIGURATION"
echo