#!/usr/bin/env bash

function link_or_rm() {
  local env="$1"
  local tmp="$2"
  if [[ -z "${env}" ]]; then
    # No auth sock; remove symlink, if any.
    rm -f -- "${tmp}"
  elif [[ "${env}" != "${tmp}" ]]; then
    # Construct expected symlink to point to auth sock.
    ln -snf -- "${env}" "${tmp}"
  fi
}

# Get invocation, stx or mtx
zero="$0"
invocation=$(basename "$zero")

case "$invocation" in
  tmux_control)
  declare -a tmux_links
  tmux_links=( stx mtx sx mx tls )
  for link in "${tmux_links[@]}"; do
    if [[ ! -h "${HOME}/bin/${link}" ]]; then
      (cd "${HOME}/bin" && ln -s "tmux_control" "${link}")
    fi
  done
  echo 'stx or sx for inner sessions; mtx or mx for outer sessions, tls to list all sessions' >&2
  exit 1
  ;;
  sx)
    socket="tmux_${USER}_stx"
    tmux -L "${socket}" "$@"
    exit $?
  ;;
  mx)
    socket="tmux_${USER}_mtx"
    tmux -L "${socket}" "$@"
    exit $?
  ;;
  tls)
  declare -a sockets
  readarray -d '' sockets < <(find "/tmp/tmux-$(id -u)" -maxdepth 1 -type s -print0)
  for socket in ${sockets[*]}; do
    printf '%s\n' "$socket"
    tmux -L "$(basename "${socket}")" list-sessions | sed 's/^/  /'
  done
  exit 0
esac

socket="tmux_${USER}_${invocation}"

style="inner"
if [[ "${invocation}" == mtx ]]; then
  style="outer"
fi

config="${HOME}/.tmux.conf_${style}"

session_name="default"
if [[ -n $1 ]]; then
  session_name="$1"
fi

if [[ "$1" == "test" ]]; then
  echo "invocation: ${invocation}"
  echo "config: ${config}"
  echo "session: ${session_name}"
  exit 0
fi

if [[ ! -f "${config}" ]]; then
  echo "Didn't find ${config}" >&2
  exit 1
fi

# Make the temp directory if it doesn't exist
home_sock_folder="${HOME}/.tmp"
if ! [ -d "${home_sock_folder}" ]; then
  mkdir -m 700 "${home_sock_folder}"
fi

# Symlinks to sockets that might change out from under tmux
if [[ -z "${TMUX}" ]] || [[ "$style" == "inner" && "$TMUX" =~ mtx ]]; then
  ssh_auth_sock_symlink="${home_sock_folder}/ssh_auth_sock"
  fwd_ssh_sock_symlink="${home_sock_folder}/fwd_ssh_auth_sock"
  sway_sock_symlink="${home_sock_folder}/sway_sock"
  i3_sock_symlink="${home_sock_folder}/i3_sock"
  link_or_rm "${SSH_AUTH_SOCK}" "${ssh_auth_sock_symlink}"
  link_or_rm "${FWD_SSH_AUTH_SOCK}" "${fwd_ssh_sock_symlink}"
  # SWAYSOCK == I3SOCK, probably some Xwayland compatability thing
  link_or_rm "${SWAYSOCK}" "${sway_sock_symlink}"
  link_or_rm "${SWAYSOCK}" "${i3_sock_symlink}"

  # See if there are any sessions on this socket
  echo running: tmux -L "${socket}" list-sessions
  tmux -L "${socket}" list-sessions
  echo results: $?
  if [[ $? != 0 ]]; then
    # No tmux session @ $socket
    exec env \
	I3SOCK="${i3_sock_symlink}" \
	SWAYSOCK="${sway_sock_symlink}" \
	SSH_AUTH_SOCK="${ssh_auth_sock_symlink}" \
	FWD_SSH_AUTH_SOCK="${f}" \
	tmux -f "${config}" -L "${socket}" ${args} new-session -s "${session_name}"

  elif tmux -L "${socket}" list-sessions 2>/dev/null | grep "^${session_name}:" &>/dev/null; then
    # A named session exists
    exec env \
	I3SOCK="${i3_sock_symlink}" \
	SWAYSOCK="${sway_sock_symlink}" \
	SSH_AUTH_SOCK="${ssh_auth_sock_symlink}" \
	FWD_SSH_AUTH_SOCK="${f}" \
	tmux -f "${config}" -L "${socket}" ${args} attach -t "${session_name}"
  else
    # Some session lives at that socket but it's a different name than is given
    exec env \
	I3SOCK="${i3_sock_symlink}" \
	SWAYSOCK="${sway_sock_symlink}" \
	SSH_AUTH_SOCK="${ssh_auth_sock_symlink}" \
	FWD_SSH_AUTH_SOCK="${f}" \
	tmux -f "${config}" -L "${socket}" ${args} new-session -s "${session_name}"
  fi
else
  echo "Already in a tmux session. Giving up."
  exit 1
fi