git-dropbox

#!/bin/sh

DROPBOX_REPOSITORIES_PATH=`git config dropbox.folder`
eval DROPBOX_REPOSITORIES_PATH=$DROPBOX_REPOSITORIES_PATH

if [ ! "$DROPBOX_REPOSITORIES_PATH" -o ! -d "$DROPBOX_REPOSITORIES_PATH" ]; then
  echo "Do \"git config --global dropbox.folder \$HOME/Dropbox/repositories\" first"
  exit 1
fi

shorten_home() {
  if [ ${1#$HOME} = $1 ]; then
    echo "$1"
  else
    echo "~${1#$HOME}"
  fi
}

cmd_clone() {
  if git rev-parse --is-inside-work-tree > /dev/null 2>&1; then
    echo "Do not clone inside other working tree."
    return 1
  fi
  if [ -z "$1" ]; then
    echo "Specify an existing repository name."
    return 1
  fi
  DROPBOX_REPO=$DROPBOX_REPOSITORIES_PATH/$1.git
  if [ ! -d $DROPBOX_REPO ]; then
    echo "Specify an existing repository name."
    return 1
  fi
  CLONE_TO=`pwd`/$1
  if [ -d $CLONE_TO ]; then
    echo "$2 is already cloned"
    return 1
  fi

  echo "Clone $(shorten_home $DROPBOX_REPO)"
  echo "To    $(shorten_home $CLONE_TO)"
  git clone $DROPBOX_REPO $CLONE_TO
  cd $CLONE_TO
  git remote rename origin dropbox
  return 0
}

cmd_sync() {
  if ! git rev-parse --is-inside-work-tree > /dev/null 2>&1; then
    echo "Please invoke inside a working tree."
    return 1
  fi
  cd `pwd`/`git rev-parse --show-cdup`

  DROPBOX_REPO=$DROPBOX_REPOSITORIES_PATH/$(basename `pwd`).git
  CURRENT_REPO=`pwd`

  if [ -z "$(git remote | grep dropbox)" ]; then
    if [ ! -d $DROPBOX_REPO ]; then
      echo "Create a mirror: $(shorten_home $DROPBOX_REPO)"
      git clone --mirror $CURRENT_REPO $DROPBOX_REPO
      git --git-dir=$DROPBOX_REPO remote rm origin
      git remote add dropbox $DROPBOX_REPO
    else
      echo "Remote repository exists: $(shorten_home $DROPBOX_REPO)"
      echo "Set the remote 'dropbox'"
      git remote add dropbox $DROPBOX_REPO
      git fetch dropbox && git push --all dropbox
    fi
  else
    REMOTE_INFO=$(git remote show -n dropbox | grep "Fetch URL:")
    CURRENT_REMOTE_REPO=${REMOTE_INFO##  Fetch URL: }
    if [ $DROPBOX_REPO != $CURRENT_REMOTE_REPO ]; then
      echo "Current 'dropbox' remote is different from the assumption"
      echo "Current: $CURRENT_REMOTE_REPO"
      echo "Expect:  $DROPBOX_REPO"
      return 1
    fi
    git fetch dropbox && git push --all dropbox
  fi
}

main() {
  if [ -z "$1" ]; then
    COMMAND="sync"
  else
    COMMAND=$1
  fi
  shift

  case "$COMMAND" in
    "clone" ) cmd_clone "$@" ;;
    "sync" ) cmd_sync "$@" ;;
    * ) echo "Unknown command $COMMAND"; return 1 ;;
  esac
}

main "$@"