#!/bin/bash
#
# Put the .git submodule folder back to the right place.
#
# When initializing a git submodule, git usually puts the
# submodules' .git folder inside the .git/modules folder
# in the parent repository.
#
# While this keeps all submodule metadata in a single place,
# it may not be confortable when you also want to develop
# the submodule.
#
# This plugin simply moves the submodules' git folder back
# to the standard place.

# Parameters
BASENAME="`basename $0`"
MODULE="$1"

# Checks
if [ -z "$MODULE" ]; then
  echo "usage: $BASENAME <submodule-path>"
  exit 1
elif [ ! -d "$MODULE" ]; then
  echo "module not found: $MODULE"
  exit 1
elif [ -d "$MODULE/.git" ]; then
  echo "module $MODULE already converted"
  exit 1
elif [ ! -e ".git" ]; then
  echo "please run this command in the top-level repository folder"
  exit 1
elif [ ! -f "$MODULE/.git" ]; then
  echo "$BASENAME: not a file, or file not found: $MODULE/.git"
  exit 1
elif [ -e "$MODULE/.gitmodules" ]; then
  echo "$BASENAME: this repository has submodules; use git-submodule-move-all-git-dirs instead"
  exit 1
fi

# Setup
RELATIVE_REPO_DIR="$(cd $MODULE &> /dev/null && cd `cut -d : -f 2 .git` &> /dev/null && pwd)"
REPO_DIR="`pwd`"
MODULE_DIR="`cd $MODULE &> /dev/null && pwd`"

if [ -z "$RELATIVE_REPO_DIR" ] || [ ! -d "$RELATIVE_REPO_DIR" ]; then
  RELATIVE_REPO_DIR=".git/modules/$RELATIVE_REPO_DIR/$(echo $MODULE_DIR | sed -e "s|^$REPO_DIR/||")"
fi

if [ -z "$RELATIVE_REPO_DIR" ] || [ ! -d "$RELATIVE_REPO_DIR" ]; then
  echo "$BASENAME: no git folder found for submodule $MODULE"
  exit 1
fi

if [ ! -e "$RELATIVE_REPO_DIR/config" ]; then
  echo "$BASENAME: config not found at $RELATIVE_REPO_DIR/config"
  exit 1
fi

# Convert
rm $MODULE/.git && \
mv "$RELATIVE_REPO_DIR" "$MODULE/.git" && \
sed -i -e '/worktree =/d' "$MODULE/.git/config"