#!/usr/bin/env bash

set -euo pipefail

self=$(git config --get user.name)
head=$(git head)

for branch in $(git for-each-ref --format='%(refname:short)' refs/heads/); do
  if [ "$branch" == "$head" ]; then
    continue
  fi

  if git merge-base --is-ancestor "$branch" origin/HEAD; then
    git branch -d "$branch"
    continue
  fi

  author=$(git show --no-patch --pretty='%an' "$branch")
  if [ "$author" != "$self" ]; then
    git branch -D "$branch"
  fi
done