using System.Collections.Generic;
using UnityEngine;
using Firebase.Firestore;
using Firebase.Auth;
using Firebase.Extensions;

namespace BulletHellTemplate
{
    /// <summary>
    /// Handles saving and loading reward data from Firebase and PlayerPrefs.
    /// Prevents multiple calls to Firebase during initialization.
    /// </summary>
    public static class RewardSaveManager
    {
        /// <summary>
        /// Loads rewards from Firestore for a specified collection and invokes a callback with the data.
        /// </summary>
        public static void LoadRewards(string collectionName, System.Action<Dictionary<string, object>> onLoaded)
        {
            FirebaseUser user = FirebaseAuth.DefaultInstance.CurrentUser;
            if (user == null) return;

            FirebaseFirestore db = FirebaseFirestore.DefaultInstance;
            DocumentReference docRef = db.Collection("Players").Document(user.UserId).Collection(collectionName).Document("RewardData");
            docRef.GetSnapshotAsync().ContinueWithOnMainThread(task =>
            {
                if (task.IsCompleted && task.Result.Exists)
                {
                    Dictionary<string, object> data = task.Result.ToDictionary();
                    onLoaded?.Invoke(data);
                }
                else
                {
                    Debug.LogError("Failed to load reward data.");
                    onLoaded?.Invoke(null);
                }
            });
        }

        /// <summary>
        /// Saves rewards to Firestore for a specified collection, and also stores them locally in PlayerPrefs.
        /// </summary>
        public static void SaveRewards(string collectionName, Dictionary<string, object> data)
        {
            FirebaseUser user = FirebaseAuth.DefaultInstance.CurrentUser;
            if (user == null) return;

            FirebaseFirestore db = FirebaseFirestore.DefaultInstance;
            DocumentReference docRef = db.Collection("Players").Document(user.UserId).Collection(collectionName).Document("RewardData");
            docRef.SetAsync(data).ContinueWithOnMainThread(task =>
            {
                if (task.IsCompleted)
                {
                    Debug.Log($"{collectionName} rewards saved successfully.");
                }
                else
                {
                    Debug.LogError($"Failed to save {collectionName} rewards: {task.Exception}");
                }
            });

            // Save locally
            SaveRewardsLocally(collectionName, data);
        }

        /// <summary>
        /// Saves rewards data locally in PlayerPrefs as JSON.
        /// </summary>
        private static void SaveRewardsLocally(string collectionName, Dictionary<string, object> data)
        {
            string json = JsonUtility.ToJson(data);
            PlayerPrefs.SetString(collectionName, json);
            PlayerPrefs.Save();
        }

        /// <summary>
        /// Loads rewards data from PlayerPrefs if available.
        /// </summary>
        public static Dictionary<string, object> LoadRewardsLocally(string collectionName)
        {
            string json = PlayerPrefs.GetString(collectionName, null);
            return string.IsNullOrEmpty(json) ? null : JsonUtility.FromJson<Dictionary<string, object>>(json);
        }
    }
}