#!/usr/bin/env bash

set -Eeuo pipefail

host_name="$(hostname)"
if [[ "$#" -ne 0 ]]; then
  echo "Usage: signal_link.sh" >&2
  exit 2
fi

service_name="signal-cli"
data_dir="/var/lib/signal-cli"
link_pid=""
temp_dir=""
restart_service=false

cleanup() {
  if [[ -n "$link_pid" ]] && kill -0 "$link_pid" 2>/dev/null; then
    kill "$link_pid" 2>/dev/null || true
    wait "$link_pid" 2>/dev/null || true
  fi

  if [[ -n "$temp_dir" ]]; then
    rm -f -- "$temp_dir/link-uri"
    rmdir -- "$temp_dir"
  fi

  if [[ "$restart_service" == true ]]; then
    sudo systemctl start "$service_name"
  fi
}
trap cleanup EXIT

restart_service=true
sudo systemctl stop "$service_name"

temp_dir="$(mktemp -d)"
link_fifo="$temp_dir/link-uri"
mkfifo "$link_fifo"

sudo -u signal-cli \
  signal-cli --data-dir "$data_dir" link --name "$host_name" >"$link_fifo" &
link_pid="$!"

if ! IFS= read -r device_uri <"$link_fifo"; then
  wait "$link_pid"
  exit 1
fi
if [[ "$device_uri" != sgnl://linkdevice\?* ]]; then
  echo "signal-cli returned an invalid device link URI." >&2
  exit 1
fi

echo "Run this command manually on jeeves in another dotfiles dir:"
printf "sudo ./scripts/signal/authorize.sh %q\n" "$device_uri"
echo "Waiting for jeeves to authorize this device..."

wait "$link_pid"
link_pid=""
echo "$host_name is now linked to the Signal account on jeeves."