# Copyright (c) 2007 Lars Hjemli
 
 dashless=$(basename "$0" | sed -e 's/-/ /')
-USAGE="[--quiet] add [-b branch] [-f|--force] [--reference <repository>] [--] <repository> [<path>]
+USAGE="[--quiet] add [-b <branch>] [-f|--force] [--name <name>] [--reference <repository>] [--] <repository> [<path>]
    or: $dashless [--quiet] status [--cached] [--recursive] [--] [<path>...]
    or: $dashless [--quiet] init [--] [<path>...]
-   or: $dashless [--quiet] update [--init] [-N|--no-fetch] [-f|--force] [--rebase] [--reference <repository>] [--merge] [--recursive] [--] [<path>...]
+   or: $dashless [--quiet] update [--init] [--remote] [-N|--no-fetch] [-f|--force] [--rebase] [--reference <repository>] [--merge] [--recursive] [--] [<path>...]
    or: $dashless [--quiet] summary [--cached|--files] [--summary-limit <n>] [commit] [--] [<path>...]
    or: $dashless [--quiet] foreach [--recursive] <command>
-   or: $dashless [--quiet] sync [--] [<path>...]"
+   or: $dashless [--quiet] sync [--recursive] [--] [<path>...]"
 OPTIONS_SPEC=
 . git-sh-setup
 . git-sh-i18n
 recursive=
 init=
 files=
+remote=
 nofetch=
 update=
 prefix=
+custom_name=
 
 # The function takes at most 2 arguments. The first argument is the
 # URL that navigates to the submodule origin repo. When relative, this URL
        fi
 }
 
+#
+# Print a submodule configuration setting
+#
+# $1 = submodule name
+# $2 = option name
+# $3 = default value
+#
+# Checks in the usual git-config places first (for overrides),
+# otherwise it falls back on .gitmodules.  This allows you to
+# distribute project-wide defaults in .gitmodules, while still
+# customizing individual repositories if necessary.  If the option is
+# not in .gitmodules either, print a default value.
+#
+get_submodule_config () {
+       name="$1"
+       option="$2"
+       default="$3"
+       value=$(git config submodule."$name"."$option")
+       if test -z "$value"
+       then
+               value=$(git config -f .gitmodules submodule."$name"."$option")
+       fi
+       printf '%s' "${value:-$default}"
+}
+
+
 #
 # Map submodule path to submodule name
 #
 module_clone()
 {
        sm_path=$1
-       url=$2
-       reference="$3"
+       name=$2
+       url=$3
+       reference="$4"
        quiet=
        if test -n "$GIT_QUIET"
        then
 
        gitdir=
        gitdir_base=
-       name=$(module_name "$sm_path" 2>/dev/null)
-       test -n "$name" || name="$sm_path"
        base_name=$(dirname "$name")
 
        gitdir=$(git rev-parse --git-dir)
                --reference=*)
                        reference="$1"
                        ;;
+               --name)
+                       case "$2" in '') usage ;; esac
+                       custom_name=$2
+                       shift
+                       ;;
                --)
                        shift
                        break
                exit 1
        fi
 
+       if test -n "$custom_name"
+       then
+               sm_name="$custom_name"
+       else
+               sm_name="$sm_path"
+       fi
+
        # perhaps the path exists and is already a git repo, else clone it
        if test -e "$sm_path"
        then
                fi
 
        else
-
-               module_clone "$sm_path" "$realrepo" "$reference" || exit
+               if test -d ".git/modules/$sm_name"
+               then
+                       if test -z "$force"
+                       then
+                               echo >&2 "$(eval_gettext "A git directory for '\$sm_name' is found locally with remote(s):")"
+                               GIT_DIR=".git/modules/$sm_name" GIT_WORK_TREE=. git remote -v | grep '(fetch)' | sed -e s,^,"  ", -e s,' (fetch)',, >&2
+                               echo >&2 "$(eval_gettext "If you want to reuse this local git directory instead of cloning again from")"
+                               echo >&2 "  $realrepo"
+                               echo >&2 "$(eval_gettext "use the '--force' option. If the local git directory is not the correct repo")"
+                               die "$(eval_gettext "or you are unsure what this means choose another name with the '--name' option.")"
+                       else
+                               echo "$(eval_gettext "Reactivating local git directory for submodule '\$sm_name'.")"
+                       fi
+               fi
+               module_clone "$sm_path" "$sm_name" "$realrepo" "$reference" || exit
                (
                        clear_local_git_env
                        cd "$sm_path" &&
                        esac
                ) || die "$(eval_gettext "Unable to checkout submodule '\$sm_path'")"
        fi
-       git config submodule."$sm_path".url "$realrepo"
+       git config submodule."$sm_name".url "$realrepo"
 
        git add $force "$sm_path" ||
        die "$(eval_gettext "Failed to add submodule '\$sm_path'")"
 
-       git config -f .gitmodules submodule."$sm_path".path "$sm_path" &&
-       git config -f .gitmodules submodule."$sm_path".url "$repo" &&
+       git config -f .gitmodules submodule."$sm_name".path "$sm_path" &&
+       git config -f .gitmodules submodule."$sm_name".url "$repo" &&
+       if test -n "$branch"
+       then
+               git config -f .gitmodules submodule."$sm_name".branch "$branch"
+       fi &&
        git add --force .gitmodules ||
        die "$(eval_gettext "Failed to register submodule '\$sm_path'")"
 }
                -i|--init)
                        init=1
                        ;;
+               --remote)
+                       remote=1
+                       ;;
                -N|--no-fetch)
                        nofetch=1
                        ;;
                fi
                name=$(module_name "$sm_path") || exit
                url=$(git config submodule."$name".url)
+               branch=$(get_submodule_config "$name" branch master)
                if ! test -z "$update"
                then
                        update_module=$update
 
                if ! test -d "$sm_path"/.git -o -f "$sm_path"/.git
                then
-                       module_clone "$sm_path" "$url" "$reference"|| exit
+                       module_clone "$sm_path" "$name" "$url" "$reference" || exit
                        cloned_modules="$cloned_modules;$name"
                        subsha1=
                else
                        die "$(eval_gettext "Unable to find current revision in submodule path '\$sm_path'")"
                fi
 
+               if test -n "$remote"
+               then
+                       if test -z "$nofetch"
+                       then
+                               # Fetch remote before determining tracking $sha1
+                               (clear_local_git_env; cd "$sm_path" && git-fetch) ||
+                               die "$(eval_gettext "Unable to fetch in submodule path '\$sm_path'")"
+                       fi
+                       remote_name=$(clear_local_git_env; cd "$sm_path" && get_default_remote)
+                       sha1=$(clear_local_git_env; cd "$sm_path" &&
+                               git rev-parse --verify "${remote_name}/${branch}") ||
+                       die "$(eval_gettext "Unable to find current ${remote_name}/${branch} revision in submodule path '\$sm_path'")"
+               fi
+
                if test "$subsha1" != "$sha1" -o -n "$force"
                then
                        subforce=$force
        done |
        if test -n "$for_status"; then
                if [ -n "$files" ]; then
-                       gettextln "# Submodules changed but not updated:"
+                       gettextln "Submodules changed but not updated:" | git stripspace -c
                else
-                       gettextln "# Submodule changes to be committed:"
+                       gettextln "Submodule changes to be committed:" | git stripspace -c
                fi
-               echo "#"
-               sed -e 's|^|# |' -e 's|^# $|#|'
+               printf "\n" | git stripspace -c
+               git stripspace -c
        else
                cat
        fi
 cmd_status()
 {
        # parse $args after "submodule ... status".
-       orig_flags=
        while test $# -ne 0
        do
                case "$1" in
                        break
                        ;;
                esac
-               orig_flags="$orig_flags $(git rev-parse --sq-quote "$1")"
                shift
        done
 
                                prefix="$displaypath/"
                                clear_local_git_env
                                cd "$sm_path" &&
-                               eval cmd_status "$orig_args"
+                               eval cmd_status
                        ) ||
                        die "$(eval_gettext "Failed to recurse into submodule path '\$sm_path'")"
                fi
                        GIT_QUIET=1
                        shift
                        ;;
+               --recursive)
+                       recursive=1
+                       shift
+                       ;;
                --)
                        shift
                        break
 
                if git config "submodule.$name.url" >/dev/null 2>/dev/null
                then
-                       say "$(eval_gettext "Synchronizing submodule url for '\$name'")"
+                       say "$(eval_gettext "Synchronizing submodule url for '\$prefix\$sm_path'")"
                        git config submodule."$name".url "$super_config_url"
 
                        if test -e "$sm_path"/.git
                                cd "$sm_path"
                                remote=$(get_default_remote)
                                git config remote."$remote".url "$sub_origin_url"
+
+                               if test -n "$recursive"
+                               then
+                                       prefix="$prefix$sm_path/"
+                                       eval cmd_sync
+                               fi
                        )
                        fi
                fi