bluetooth

#!/usr/bin/env bash

set -euo pipefail

assert_command() {
  if ! type "${1}" >/dev/null 2>&1; then
    echo "${2:-"command not found: ${1}"}"
    exit 1
  fi
}

assert_val() {
  if [[ -z "${1}" ]]; then
    echo "${2}"
    exit 1
  fi
}

assert_func() {
  if ! declare -F "${1}" >/dev/null; then
    echo "${2}"
    exit 1
  fi
}

_darwin_power() {
  case "${1:-"?"}" in
    1|on)  blueutil --power 1;;
    0|off) blueutil --power 0;;
    ?)     blueutil --power  ;;
    *)     exit 1            ;;
  esac
}

_darwin_restart() {
  bluetooth power off
  bluetooth power on
}

_darwin_connect() {
  local disconnect="no"
  while (( "$#" )); do
    case "${1}" in
      --disconnect)
        disconnect="yes"
        shift;;
      *)
        shift;;
    esac
  done
    
  local -r blob="$(blueutil --format=json --paired)"
  local -r name="$(echo "${blob}" | jq -r '.[].name' | fzf)"
  local -r id="$(echo "${blob}" | jq -r ".[] | select(.name =\"${name}\") | .address")"
  if [[ "${disconnect}" = "yes" ]]; then
    blueutil --disconnect "${id}"
  fi
  blueutil --connect "${id}"
}

_linux_power() {
  case "${1:-"?"}" in
    1|on)  bluetoothctl power on;;
    0|off) bluetoothctl power off;;
    ?)     bluetoothctl show | grep --quiet "Powered: yes" && echo "1" || echo "0" ;;
    *)     exit 1            ;;
  esac
}

_linux_restart() {
  if [[ -z "$(bluetoothctl list)" ]]; then
    sudo modprobe -r btusb
    sudo modprobe btusb
    while [[ -z "$(bluetoothctl list)" ]]; do
      sleep 0.2
    done
  fi
  bluetooth power off
  bluetooth power on
}

_linux_connect() {
  local disconnect="no"
  while (( "$#" )); do
    case "${1}" in
      --disconnect)
        disconnect="yes"
        shift;;
      *)
        shift;;
    esac
  done

  local -r blob="$(bluetoothctl paired-devices)"
  local -r name="$(echo "${blob}" | sed -e 's/\S* \S* //' | fzf)"
  assert_val "${name}" "failed to select device"
  local -r id="$(echo "${blob}" | grep "${name}" | awk '{ print $2 }')"
  if [[ "${disconnect}" = "yes" ]]; then
    bluetoothctl disconnect "${id}"
  fi
  bluetoothctl connect "${id}"
}

declare OS=""
case "${OSTYPE}" in
  darwin*)
    assert_command blueutil
    OS="darwin"
    ;;
  linux*)
    assert_command bluetoothctl
    OS="linux"
    ;;
  *)
    echo "Unsupported OS!"
    exit 1;;
esac

declare -r cmd="${1:-"help"}"
shift || true

case "${cmd}" in
  help)
    cat << HELP
USAGE:
  bluetooth power [0|1|on|off]
  bluetooth restart
  bluetooth connect
HELP
    exit 0
esac

declare -r func="_${OS}_${cmd}"
assert_func "${func}" "invalid command: ${cmd}"

$func $@