.functions

# Create a new directory and enter it
function md() {
	mkdir -p "$@" && cd "$@"
}

# find shorthand
function f() {
    find . -name "$1"
}

function parse_git_branch() {
    git branch --no-color 2> /dev/null | sed -e '/^[^*]/d' -e 's/* \(.*\)/\1/'
}

function greb() {
  timestamp="$(date +%Y%m%d%H%M%S)"
  use_onto=""

  # Parameter Checking
  onto_branch="$1"
  if [ -z "$onto_branch" ]; then
    echo "Usage:"
    echo "       git checkout <featurebranch_name>"
    echo "       greb <mainlinebranch_name>"
    echo ""
    echo "example:"
    echo "       $ git checkout my_bug_fix"
    echo "       $ greb development"
    return
  fi

  this_branch="$(parse_git_branch)"
  if [ -z "$this_branch" ]; then
    echo "ERROR: you are not currently in a git repository"
    return
  fi

  if [ "$this_branch" = "$onto_branch" ]; then
    echo "ERROR: branches must not be the same"
    return
  fi

  if [ "$2" = "onto" ]; then
    use_onto="true"
  fi

  # Main Function
  commit_count=$(git reflog show "$this_branch" | grep 'commit: ' | wc -l | tr -d ' ')

  # Ensure the new base branch is up to date
  echo "Fetching all changes from remote..."
  git fetch origin
  if [ "$?" != "0" ]; then
    echo "'git fetch origin' Unexpected error: $?"
    return
  fi

  echo "Making sure '$onto_branch' is up to date..."
  git checkout "$onto_branch"
  if [ "$?" != "0" ]; then
    echo "'git checkout \"$onto_branch\"' Unexpected error: $?"
    return
  fi

  git merge --ff-only "origin/$onto_branch"
  if [ "$?" != "0" ]; then
    echo "Could not fast forward '$onto_branch', making a backup before pulling changes."

    no_ff="true"

    git checkout -b "${onto_branch}-$timestamp" &&
      git branch -D "$onto_branch" &&
      git checkout "$onto_branch"

    if [ "$?" != "0" ]; then
      echo "<Unexpected error: $?> while forcing '$onto_branch' to sync with origin"
      return
    fi
  fi

  # Ensure the current branch is up to date
  echo "Making a backup of '$this_branch'"
  git checkout "$this_branch" &&
    git checkout -b "${this_branch}-$timestamp" &&
    git checkout "$this_branch"

  if [ "$?" != "0" ]; then
    echo "<Unexpected error: $?> while backing up '$this_branch'"
    return
  fi

  echo "Making sure '$this_branch' is up to date..."
  git merge --ff-only "origin/$this_branch"
  if [ "$?" != "0" ]; then
    git rebase "origin/$this_branch"
    if [ "$?" != "0" ]; then
      echo "'git rebase \"origin/$this_branch\"' Unexpected error: $?"
      return
    fi
  fi

  # Do the rebase
  if [ -n "$use_onto" ]; then
    echo "Rebasing $commit_count commits from '$this_branch' onto '$onto_branch'"
    git rebase "HEAD~$commit_count" --onto "$onto_branch"
  else
    echo "Rebasing '$this_branch' onto '$onto_branch'"
    git rebase "$onto_branch"
  fi
}