#!/usr/bin/env bash

set -eu

link="$HOME/.ssh/ssh_auth_sock"

if [[
  -n "${SSH_CONNECTION:-}" &&
  -n "${SSH_AUTH_SOCK:-}" &&
  "$SSH_AUTH_SOCK" != "$link" &&
  -S "$SSH_AUTH_SOCK"
]]; then
  mkdir -p "$HOME/.ssh"
  chmod 700 "$HOME/.ssh"
  ln -snf "$SSH_AUTH_SOCK" "$link"
fi

# When our link isn't valid, try to make it so.
if ! [ -S "$link" ]; then
  for agent in "$HOME/.ssh/agent"/*; do
    if SSH_AUTH_SOCK="$agent" timeout 2s ssh-add -l > /dev/null 2>&1; then
      ln -snf "$agent" "$link"
      break
    fi
  done
fi

if [ -S "$link" ]; then
  printf '%s\n' "$link"
else
  exit 1
fi