setup-stage: Optionally reconfigure topic stage

When the topic stage has already been configured present the current
configuration and prompt for optional reconfiguration.  While at it,
make the topic stage remote name configurable by the project.

setup-stage

@@ -37,17 +37,43 @@ die() {
 cd "${BASH_SOURCE%/*}" &&
 
 # Load the project configuration.
-url=$(git config -f config --get stage.url) &&
+fetchurl=$(git config -f config --get stage.url) &&
-pushurl=$(git config -f config --get stage.pushurl || echo '') ||
+pushurl_=$(git config -f config --get stage.pushurl || echo '') &&
+remote=$(git config -f config --get stage.remote || echo 'stage') ||
 die 'This project is not configured to use a topic stage.'
 
-# Configure the remote if necessary.
+# Get current stage push URL.
-if git config remote.stage.url >/dev/null; then
+pushurl=$(git config --get remote."$remote".pushurl ||
-	echo 'Topic stage already configured.'
+	  git config --get remote."$remote".url || echo '') &&
-else
+
-	echo 'Setting up the topic stage...' &&
+# Tell user about current configuration.
-	git remote add stage "$url" &&
+if test -n "$pushurl"; then
-	if test -n "$pushurl"; then
+	echo 'Remote "'"$remote"'" is currently configured to push to
-		git config remote.stage.pushurl "$pushurl"
+
+  '"$pushurl"'
+' &&
+	read -ep 'Reconfigure Topic Stage? [y/N]: ' ans &&
+	if [ "$ans" == "y" ] || [ "$ans" == "Y" ]; then
+		setup=1
+	else
+		setup=''
 	fi
-fi || die 'Could not add the topic stage remote.'
+else
+	setup=1
+fi
+
+# Perform setup if necessary.
+if test -n "$setup"; then
+	echo 'Setting up the topic stage...' &&
+	if test -z "$pushurl"; then
+		git remote add "$remote" "$fetchurl"
+	else
+		git config remote."$remote".url "$fetchurl"
+	fi &&
+	pushurl="${pushurl_}" &&
+	git config remote."$remote".pushurl "$pushurl" &&
+	echo 'Remote "'"$remote"'" is now configured to push to
+
+  '"$pushurl"'
+'
+fi || die 'Could not configure the topic stage remote.'