Configure GitHub remotes for HTTPS fetch and SSH push

github-remote

#!/usr/bin/env bash
set -Eeuo pipefail

if [[ ! ( "${1-}" =~ ^([-_[:alnum:]]+)/([-_.[:alnum:]]+)$ ) ]]; then
  echo "Usage: ${0##*/} <owner>/<repo>" >&2
  exit 1
fi

owner="${BASH_REMATCH[1]}"
repo="${BASH_REMATCH[2]}"

https="https://github.com/$owner/$repo.git"
ssh="git@github.com:$owner/$repo.git"

if git rev-parse --is-inside-work-tree >/dev/null 2>&1; then
  if git remote | grep --quiet "^$owner$"; then
    echo "Configuring GitHub remote $owner/$repo for HTTPS fetch and SSH push" >&2

    git remote set-url "$owner" "$https"
    git remote set-url --push "$owner" "$ssh"
  else
    echo "Adding GitHub remote $owner/$repo with HTTPS fetch and SSH push" >&2

    git remote add -f "$owner" "$https"
    git remote set-url --push "$owner" "$ssh"
  fi
else
  echo "Cloning from GitHub remote $owner/$repo with HTTPS fetch and SSH push" >&2

  git clone --origin "$owner" "$https" "$repo"
  cd "$repo"
  git remote set-url --push "$owner" "$ssh"
fi