From b6a97e9361df6e20117101d582f6e70265d40d96 Mon Sep 17 00:00:00 2001
From: Mabel Zhang <mabel@openrobotics.org>
Date: Sat, 30 Apr 2022 01:53:06 -0400
Subject: [PATCH] subcommand bash completeion for gui and plugin

Signed-off-by: Mabel Zhang <mabel@openrobotics.org>
---
 etc/ign.bash_completion.sh | 30 +++++++++++++++++++++++++-----
 1 file changed, 25 insertions(+), 5 deletions(-)

diff --git a/etc/ign.bash_completion.sh b/etc/ign.bash_completion.sh
index 94c1872..6975520 100644
--- a/etc/ign.bash_completion.sh
+++ b/etc/ign.bash_completion.sh
@@ -1,14 +1,21 @@
+#!/usr/bin/env bash
+
 # ign bash completion
 
 function _ign
 {
   local prev cur cmd opts
   local ign="$1"
-  COMPREPLY=()
   cur="$2"
   prev="$3"
 
-  # searching for the command
+  # Return value
+  COMPREPLY=()
+
+  # Look for the first command that is not an option (-*)
+  # COMP_WORDS: array of words in current command line COMP_LINE
+  # COMP_CWORD: index of word containing current cursur location
+  # COMP_LINE: line entered so far
   for ((i=1; $i<=$COMP_CWORD; i++)); do
     if [[ ${COMP_WORDS[i]} != -* ]]; then
       cmd="${COMP_WORDS[i]}"
@@ -16,16 +23,29 @@ function _ign
     fi
   done
 
+  # On a word after top-level command ign. It may be an option (-*)
   if [[ "$cur" == -* ]] || [[ "$prev" != "ign" ]]; then
 
+    # Subcommand is help
     if [[ "$cmd" == "help" ]]; then
       opts=$(ign --commands)
+
+    # Subcommand is a library name or an option (-*)
     else
-      COMPREPLY=($(compgen -f  -- "${COMP_WORDS[${COMP_CWORD}]}" ))
-      complete -o filenames -o nospace -F "_ign" "ign"
-      return
+      # Complete subcommands
+      case "$cmd" in
+        gui)
+          _ign_gui
+          return
+          ;;
+        plugin)
+          _ign_plugin
+          return
+          ;;
+      esac
     fi
 
+  # on first word, top-level command (ign)
   else
     opts="$(ign --commands) help"
   fi