using System;
using UnityEngine;

namespace IchniOnline.Online.Logic
{
    public class IchniProtocolHandler : MonoBehaviour
    {
        private static IchniProtocolHandler _instance;
        public static IchniProtocolHandler Instance => _instance;

        private void Awake()
        {
            if (_instance != null)
            {
                Destroy(gameObject);
                return;
            }

            _instance = this;
            DontDestroyOnLoad(gameObject);

            Application.deepLinkActivated += OnDeepLinkActivated;

            if (!string.IsNullOrEmpty(Application.absoluteURL))
            {
                OnDeepLinkActivated(Application.absoluteURL);
            }
        }

        private void OnDestroy()
        {
            if (_instance == this)
            {
                Application.deepLinkActivated -= OnDeepLinkActivated;
            }
        }

        private void OnDeepLinkActivated(string url)
        {
            if (string.IsNullOrEmpty(url))
            {
                Debug.LogWarning("[IchniProtocolHandler] Deep link URL is empty");
                return;
            }

            Debug.Log($"[IchniProtocolHandler] Deep link activated: {url}");

            if (url.StartsWith("ichni://auth"))
            {
                HandleAuthCallback(url);
            }
            else
            {
                Debug.LogWarning($"[IchniProtocolHandler] Unknown deep link: {url}");
            }
        }

        private void HandleAuthCallback(string url)
        {
            try
            {
                var uri = new Uri(url);
                var query = uri.Query.TrimStart('?');
                var queryParams = ParseQueryString(query);
                var token = queryParams.ContainsKey("token") ? queryParams["token"] : null;

                if (!string.IsNullOrEmpty(token))
                {
                    Debug.Log("[IchniProtocolHandler] Auth callback received, completing login");
                    IchniOnlineAuthService.HandleIchniProtocolCallback(token);
                }
                else
                {
                    var error = queryParams.ContainsKey("error") ? queryParams["error"] : null;
                    if (!string.IsNullOrEmpty(error))
                    {
                        Debug.LogError($"[IchniProtocolHandler] Auth callback error: {error}");
                    }
                    else
                    {
                        Debug.LogError("[IchniProtocolHandler] Auth callback missing token");
                    }
                }
            }
            catch (Exception ex)
            {
                Debug.LogError($"[IchniProtocolHandler] Failed to parse deep link: {ex.Message}");
            }
        }

        private static System.Collections.Generic.Dictionary<string, string> ParseQueryString(string query)
        {
            var result = new System.Collections.Generic.Dictionary<string, string>();
            if (string.IsNullOrEmpty(query)) return result;

            var pairs = query.Split('&');
            foreach (var pair in pairs)
            {
                var parts = pair.Split('=');
                if (parts.Length == 2)
                {
                    result[Uri.UnescapeDataString(parts[0])] = Uri.UnescapeDataString(parts[1]);
                }
            }
            return result;
        }
    }
}