pipewireRemote

#! /bin/bash
#
# Default socket
readonly pipeWireRunDir="/run/user/${UID}/pipewire-remote"
readonly pipeWireSocket="pipewire-0"
readonly pipeWireSocketPath="${pipeWireRunDir}/${pipeWireSocket}"
readonly pipeWirePort=5739
# Manager socket
readonly pipeWireManagerSocket="${pipeWireSocket}-manager"
readonly pipeWireManagerSocketPath="${pipeWireRunDir}/${pipeWireManagerSocket}"
readonly pipeWireManagerPort=5740
# Host selection
readonly pipeWireRemoteHost="${1}"

cleanup(){
  # Nested loop to clean on both ports
  for pidvar in SOCAT_PID1 SOCAT_PID2; do
    if [ -n "${!pidvar}" ]; then
      if ps "${!pidvar}" > /dev/null 2>&1; then
        echo "Terminating socat process at PID ${!pidvar}"
        kill "${!pidvar}"
      else
        echo "No socat process to terminate at PID ${!pidvar}"
      fi
    fi
  done

  # Kill the PIDs listening on our ports if launched by this script
  if [ "${SSH_NONMANAGER_PORT}" == "True" ]; then
    for ssh_pid in $(lsof -i tcp:${pipeWireManagerPort}\
                      |awk 'NR!=1 {print $2}'|uniq); do
      echo "Killing SSH process at PID ${ssh_pid} for nonmanager port"
      kill "${ssh_pid}"
    done
  fi
  if [ "${SSH_MANAGER_PORT}" == "True" ]; then
    for ssh_pid in $(lsof -i tcp:${pipeWirePort}\
                      |awk 'NR!=1 {print $2}'|uniq); do
      echo "Killing SSH process at PID ${ssh_pid} for manager port"
      kill "${ssh_pid}"
    done
  fi
}

wait_for_port() {
  local port=$1
  local max_attempts=5
  local attempt=1
  while ! nc -z localhost "${port}"; do
    echo "Waiting for port ${port} to be available..."
    sleep 1
    attempt=$((attempt + 1))
    if [[ "${attempt}" -gt "${max_attempts}" ]]; then
      echo "Failed to connect after ${max_attempts} attempts."
      cleanup
      exit 1
    fi
  done
}

pipewire_connect(){
  # Create the remote path, and populate it with lock files
  mkdir -p "${pipeWireRunDir}"
  touch "${pipeWireSocketPath}.lock"
  touch "${pipeWireManagerSocketPath}.lock"

  # Create SSH port forwards and ensure that the port is listening
  if ssh -L ${pipeWirePort}:localhost:${pipeWirePort} \
      -o ExitOnForwardFailure=yes \
      -o BatchMode=yes \
      "${pipeWireRemoteHost}" -fN; then
    SSH_NONMANAGER_PORT="True"
    # Wait for the SSH port forwards to be established
    wait_for_port "${pipeWirePort}"
  else
    echo "SSH port forwarding failed at port ${pipeWirePort}"
    exit 1
  fi
  if ssh -L ${pipeWireManagerPort}:localhost:${pipeWireManagerPort} \
      -o ExitOnForwardFailure=yes \
      -o BatchMode=yes \
      "${pipeWireRemoteHost}" -fN; then
    SSH_MANAGER_PORT="True"
    # Wait for the SSH port forwards to be established
    wait_for_port "${pipeWireManagerPort}"
  else
    echo "SSH port forwarding failed at port ${pipeWireManagerPort}"
    exit 1
  fi

  # Listen on SSH port forwards, and redirect to a UNIX socket
  socat UNIX-LISTEN:"${pipeWireSocketPath}",fork \
    TCP:localhost:${pipeWirePort} &
  SOCAT_PID1=${!}
  echo "socat running at PID ${SOCAT_PID1}"
  socat UNIX-LISTEN:"${pipeWireManagerSocketPath}",fork \
    TCP:localhost:${pipeWireManagerPort} &
  SOCAT_PID2=${!}
  echo "socat running at PID ${SOCAT_PID2}"
}

# Trap SIGINT (Ctrl+C) to execute the cleanup function
trap cleanup SIGINT

# Connect to the remote pipewire server
pipewire_connect

# Run coppwr (in flatpak) against the remote sockets
flatpak run --filesystem="${pipeWireRunDir}" \
  --env=PIPEWIRE_RUNTIME_DIR="${pipeWireRunDir}" \
  io.github.dimtpap.coppwr

# Clean up at the end of script
cleanup