firebase_messaging.rb

# frozen_string_literal: true

require "httparty"

class FirebaseMessaging
  include HTTParty
  default_timeout 30
  format :json
  base_uri "https://fcm.googleapis.com/fcm"

  def create_device_group(name:, ids: [])
    group_operation(key_name: name, ids: ids, type: "create")
  end

  def add_devices(key:, key_name:, ids:)
    group_operation(key: key, key_name: key_name, ids: ids, type: "add")
  end

  def remove_devices(key:, key_name:, ids:)
    group_operation(key: key, key_name: key_name, ids: ids, type: "remove")
  end

  def retrieve_notification_key(key_name:)
    params = { headers: build_header }

    self.class.get("/notification?notification_key_name=#{key_name}", params)
  end

  def send_group_notification(key:, title:, body:, data: {})
    params = {
      body: notification_body(key, title, body, data).to_json,
      headers: build_header
    }

    self.class.post("/send", params)
  end

  private

  def notification_body(key, title, body, data)
    {
      to: key,
      notification: { title: title, body: body },
      data: data,
      android: { notification: { sound: "default" } }
    }
  end

  def group_operation(**kwargs)
    body = {
      "operation": kwargs[:type],
      notification_key_name: kwargs[:key_name],
      registration_ids: kwargs[:ids]
    }.tap { |h| h.merge(notification_key: kwargs[:key]) if kwargs[:key] }

    params = { body: body.to_json, headers: build_header }

    self.class.post("/notification", params)
  end

  def build_header(extras = {})
    {
      "Authorization" => "key=#{ENV['FIREBASE_SERVER_KEY']}",
      "project_id" => ENV["FIREBASE_PROJECT_ID"],
      "Content-Type" => "application/json"
    }.merge(extras)
  end
end