using UnityEngine;
using Firebase;
using Firebase.Messaging;
using System.Threading.Tasks;

public class FirebaseManager : MonoBehaviour
{
    private static FirebaseManager _instance;
    private static bool _isInitialized = false;

    public static FirebaseManager Instance => _instance;

    void Awake()
    {
        // Singleton: keep only one instance across scenes
        if (_instance != null)
        {
            Destroy(gameObject);
            return;
        }

        _instance = this;
        DontDestroyOnLoad(gameObject);
    }

    async void Start()
    {
        if (_isInitialized) return;

        _isInitialized = true;

        Debug.Log("Initializing Firebase...");
        await InitializeFirebaseAsync();
    }

    private async Task InitializeFirebaseAsync()
    {
        var dependencyStatus = await FirebaseApp.CheckAndFixDependenciesAsync();
        if (dependencyStatus != DependencyStatus.Available)
        {
            Debug.LogError($"Firebase dependency error: {dependencyStatus}");
            return;
        }

        Debug.Log("✅ Firebase initialized successfully");

        // Register for token and message events
        FirebaseMessaging.TokenReceived += OnTokenReceived;
        FirebaseMessaging.MessageReceived += OnMessageReceived;

        // Get the FCM token manually
        var tokenTask = FirebaseMessaging.GetTokenAsync();
        await tokenTask;

        if (tokenTask.IsCompletedSuccessfully)
        {
            string token = tokenTask.Result;
            Debug.Log("🔥 FCM Token: " + token);

            // TODO: Save token to PlayFab here if needed
        }
        else
        {
            Debug.LogWarning("❌ Failed to retrieve FCM token");
        }
    }

    private void OnTokenReceived(object sender, TokenReceivedEventArgs token)
    {
        Debug.Log("📱 Token received from Firebase: " + token.Token);
        // Optional: save to PlayFab
    }

    private void OnMessageReceived(object sender, MessageReceivedEventArgs e)
    {
        if (e.Message.Notification != null)
        {
            Debug.Log($"📨 Push Notification Received: {e.Message.Notification.Title} - {e.Message.Notification.Body}");
            // Optional: Show in-game popup or route to leaderboard
        }
        else
        {
            Debug.Log("📨 Data-only message received.");
        }
    }
}