common

#!/usr/bin/env bash

in_array() { 
    local value="$1" ; shift
    for e in "$@" ; do
        if [[ "$value" == "$e" ]] ; then
            return 0
        fi
    done
    return 1
}

cp_array() {
	local _a="$1[i]" _b="$2[i]" _na i
	eval "_na=\${!$1[@]} ; $2=()"
	for i in $_na ; do
		eval "$2[i]=\${!_a}"
	done
}

cmp_array() {
	local _a="$1[i]" _b="$2[i]" _na _nb i
	eval _na=\${!$1[@]} _nb=\${!$2[@]}
	for i in $_na $_nb ; do
		[[ "${!_a}" = "${!_b}" ]] || return 1
	done
}

join_array() { 
    local delim="$1" ; shift
    result="$1" ; shift
    for e in "$@" ; do
        result+="$delim$e"
    done
    echo -n "$result"
}

check_basename() {
	if [[ -z "$basename" ]] ; then
		failwith "no basename given" 1
	fi
}

get_link_target() {
    target="$1"
    while next_target="$(readlink -n "$target")" ; do
        target="$(dirname "$target")/$next_target"
    done
    LINK_TARGET="$target"
}

# Exists immediately, writing an error message.
# $1: error message
# $2 ?: exit code
failwith() {
    local exit_code=${2:-$?}
    echo "$PROGRAM_NAME: $1" >&2
    return $exit_code
}

on_exit() {
	local exit_status=${1:-$?}
	if (( $exit_status != 0 )) ; then
		failwith "fatal error occurred"
        exit $FATAL_ERROR_CODE
	else
		return 0
	fi
}

trap_exit_on() {
	trap on_exit EXIT
}

trap_exit_off() {
	trap - EXIT
}

# Appends a command to a trap.
# $1: command to run on trap
# $2...: names of traps to modify
trap_add() {
    trap_add_cmd=$1; shift || echo "${FUNCNAME} usage error" >& 2
    for trap_add_name in "$@"; do
        trap -- "$(
            extract_trap_cmd() { printf '%s\n' "$3"; }
            printf '%s\n' "${trap_add_cmd}"
            eval "extract_trap_cmd $(trap -p "${trap_add_name}")"
        )" "${trap_add_name}" \
            || failwith "unable to add to trap ${trap_add_name}"
    done
}
declare -f -t trap_add

PROGRAM_NAME="$(basename -- "$0")"
SCRIPT_PATH="$(get_link_target "${BASH_SOURCE[0]}")"
SCRIPT_NAME="$(basename "$SCRIPT_PATH")"
SCRIPT_DIR="$(dirname "$SCRIPT_PATH")"

FATAL_ERROR_CODE=${FATAL_ERROR_CODE:-1}

init_func_command() {
    PROGRAM_NAME="${FUNCNAME[1]}"
}