scripts/common.shi

# Common routines - do not execute directly.

# Sanitize environment
set -e
export LANG=C
export LC_ALL=C

_SHU_PROGDIR=$(dirname "$0")
_SHU_PROGNAME=$(basename "$0")

# Print an error message to stderr then exit the current process.
panic () {
    echo "ERROR: $@" >&2
    exit 1
}

# Internal verbosity level. Note that this value is inherited from
# the VERBOSE environment variable.
_SHU_VERBOSE=${VERBOSE:-1}

# Increment internal verbosity level.
increment_verbosity () {
    _SHU_VERBOSE=$(( $_SHU_VERBOSE + 1 ))
}

# Decrement internal verbosity level.
decrement_verbosity () {
    _SHU_VERBOSE=$(( $_SHU_VERBOSE - 1 ))
}

# Return internal verbosity level, clamped to 0 as a minimum bound.
get_verbosity () {
    local RET=$_SHU_VERBOSE
    if [ "$RET" -lt 0 ]; then
        RET=0
    fi
    echo "$RET"
}

# Used internally to conditionally print a message.
# $1: message's verbosity level. If greater or equal than $_SHU_VERBOSE then
#     the message will be ignored.
# $2+: message to print to stdout.
dump_n () {
    local LEVEL=$1
    shift
    if [ "$LEVEL" -lt "$_SHU_VERBOSE" ]; then
        printf "%s\n" "$@"
    fi
}

# Dump a message to standard output.
dump () {
    dump_n 0 "$@"
}

# Dump a message to standard output if --verbose was used.
log () {
    dump_n 1 "$@"
}

# Dump a message to standard output if --verbose --verbose is used.
log2 () {
    dump_n 2 "$@"
}

# Run a command, output depends on verbosity level
run () {
    local VERBOSE=$_SHU_VERBOSE
    if [ "$VERBOSE" -lt 0 ]; then
        VERBOSE=0
    fi
    if [ "$VERBOSE" -gt 1 ]; then
        echo "COMMAND: $@"
    fi
    case $VERBOSE in
        0)
             "$@" >/dev/null >&2
             ;;
        1)
            "$@" >/dev/null
            ;;
        *)
            "$@"
            ;;
    esac
}

program_directory () {
    printf "%s" "$_SHU_PROGDIR"
}

program_name () {
    printf "%s" "$_SHU_PROGNAME"
}


# Unpack a given archive into a given destination directory.
# $1: Archive path
# $2: Destination directory
unpack_archive () {
    local PKG_PATH="$1"
    local DEST_DIR="$2"
    case $PKG in
        *.tar.gz|*.tar.bz2|*.tar.xz)
            run tar xf "$PKG_PATH" -C "$DEST_DIR"
            ;;
        *.zip)
            run unzip -q -o -d "$DEST_DIR" "$PKG_PATH"
            ;;
        *)
            panic "Unsupported package format: $PKG_PATH"
            ;;
    esac
}

shell_import () {
    local SCRIPT="$_SHU_PROGDIR/$1"
    if [ ! -f "$SCRIPT" ]; then
        panic "Missing script: $SCRIPT"
    fi
    . "$SCRIPT"
}