#!/bin/bash
# Modified from https://github.com/chaitanyagupta/gitutils

green='\033[0;32m'
no_color='\033[0m'
grey='\033[0;90m'


ROOT_DIR=$(git rev-parse --show-cdup)
SUBMODULES=$(grep path ${ROOT_DIR}.gitmodules | sed 's/^.*path = //')
MOD_SUBMODULES=$(git diff --cached --name-only | grep -F "$SUBMODULES")

echo -e "Checking submodules ${grey}(pre-commit hook)${no_color} "

# If no modified submodules, exit with status code 0, else prompt the
# user and exit accordingly
if [[ -n "$MOD_SUBMODULES" ]]; then
    echo "Submodules to be committed:"
    echo "  (use \"git reset HEAD <file>...\" to unstage)"
    echo

    for SUB in $MOD_SUBMODULES
    do
        echo -e "\t${green}modified:\t$SUB${no_color}"
    done
    echo
    echo -n -e "Continue with commit? ${grey}(N|y)${no_color} "
    read -n 1 reply </dev/tty
    echo
    if [[ "$reply" == "y" || "$reply" == "Y" ]]; then
        echo "Permitting submodules to be committed..."
        exit 0
    else
        echo "Aborting commit due to submodule update."
        exit 1
    fi
else
    echo "No submodules in commit, continuing..."
    exit 0
fi