bam command line completion (BASH) T43316

Works with command completion:
  bam pa --> pack

Argument completion:
  bam pack --c --> --compress

List/checkout completion:
  bam ls some/pa --> some/path

extras/bam-bash-completion.sh

@@ -0,0 +1,66 @@
+# bam-bash-completion.sh.sh parameter-completion
+
+_bam_complete_find_root()
+{
+	PARENT=""
+	GRANDPARENT="../"
+	unset BAM_ROOT
+
+	while [ ! -d "$GRANDPARENT/.bam" ] && [ "$GRANDPARENT" != "/" ] ; do
+		PARENT=$GRANDPARENT
+		GRANDPARENT="$(realpath $PARENT/..)"
+	done
+
+	if [ ! -z "$GRANDPARENT" ] && [ "$GRANDPARENT" != "/" ] ; then
+		BAM_ROOT=$GRANDPARENT
+	fi
+	unset PARENT GRANDPARENT
+}
+
+_bam_complete()
+{
+	local cur
+	local cur_path
+	local cur_cmd
+
+	COMPREPLY=()   # Array variable storing the possible completions.
+	cur=${COMP_WORDS[COMP_CWORD]}
+	cur_cmd=""
+
+	# {a,b,c} -> a b c
+	subcommands=$(bam --help | grep -e "valid subcommands" -A2 | \
+	              tail -n-1 | tr -d '[[:space:]]' | sed "s/\,/ /g" | sed s/\{//g | sed s/\}//g)
+
+	for i in $(seq 1 $COMP_CWORD); do
+		if [[ ${COMP_WORDS[i]} =~ ^($subcommands_re)$ ]]; then
+			cur_cmd="${COMP_WORDS[i]}"
+			break
+		fi
+	done
+
+	if [[ -z "$cur_cmd" ]] ; then
+		# a b c -> a|b|c
+		subcommands_re=$(sed "s/ /\|/g"<<<$subcommands)
+
+		# print all subcommands since we didn't enter in any
+		COMPREPLY=($(compgen -W "$subcommands" -- $cur))
+	else
+		case "$cur" in
+			-*)
+				COMPREPLY=($(compgen -W "$(bam $cur_cmd --help | grep "optional arguments" -A1000 | \
+				           tail -n+2 | sed s/\,//g | sed s/\\s/\\n/g | grep -e '^\-')" -- $cur));;
+			*)
+				_bam_complete_find_root
+				if [[ ! -z "$BAM_ROOT" ]] ; then
+					cur_path=`dirname $cur"_"`"/"
+					COMPREPLY=($(compgen -W "$(bam list $cur_path --full)" -- $cur))
+				fi
+			;;
+		esac
+	fi
+
+	return 0
+}
+
+complete -F _bam_complete -o filenames bam
+