using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Net;
using System.Text;
using UnityEngine;

namespace Touka
{
    public class RequestHandler : MonoBehaviour
    {
        private static RequestHandler _instance;

        public static RequestHandler Instance
        {
            get
            {
                if (_instance != null) return _instance;
                _instance = FindObjectOfType<RequestHandler>();
                if (_instance != null) return _instance;
                var obj = new GameObject();
                _instance = obj.AddComponent<RequestHandler>();
                return _instance;
            }
        }

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

            DontDestroyOnLoad(gameObject);
        }


        public void SendGetRequest(string url, Dictionary<string, string> headers = null,
            Action<int, string> callback = null
        )
        {
            StartCoroutine(GetRequestCoroutine(url, headers, callback));
        }

        public void SendPostRequest(string url, string jsonRequestBody,
            Dictionary<string, string> headers = null, Action<int, string> callback = null)
        {
            StartCoroutine(PostRequestCoroutine(url, jsonRequestBody, headers, callback));
        }

        private static IEnumerator GetRequestCoroutine(string url, Dictionary<string, string> headers,
            Action<int, string> callback)
        {
            try
            {
                var request = (HttpWebRequest)WebRequest.Create(url);
                request.Method = "GET";

                if (headers != null)
                {
                    foreach (var header in headers)
                    {
                        request.Headers.Add(header.Key, header.Value);
                    }
                }

                using (var response = (HttpWebResponse)request.GetResponse())
                {
                    var responseStream = response.GetResponseStream();
                    if (responseStream == null)
                    {
                        throw new Exception("responseStream is null");
                    }

                    using (var reader = new StreamReader(responseStream))
                    {
                        var jsonResponse = reader.ReadToEnd();
                        Debug.Log(jsonResponse);
                        callback?.Invoke(0, jsonResponse);
                    }
                }
            }
            catch (Exception e)
            {
                callback?.Invoke(-1, e.Message);
            }


            yield return null;
        }

        private static IEnumerator PostRequestCoroutine(string url, string jsonRequestBody,
            Dictionary<string, string> headers,
            Action<int, string> callback)
        {
            try
            {
                var request = (HttpWebRequest)WebRequest.Create(url);
                request.Method = "POST";
                request.ContentType = "application/json";

                if (headers != null)
                {
                    foreach (var header in headers)
                    {
                        request.Headers.Add(header.Key, header.Value);
                    }
                }

                var byteArray = Encoding.UTF8.GetBytes(jsonRequestBody);
                request.ContentLength = byteArray.Length;

                using (var requestStream = request.GetRequestStream())
                {
                    requestStream.Write(byteArray, 0, byteArray.Length);
                }

                using (var response = (HttpWebResponse)request.GetResponse())
                {
                    var responseStream = response.GetResponseStream();
                    if (responseStream == null)
                    {
                        throw new Exception("responseStream is null");
                    }

                    using (var reader = new StreamReader(responseStream))
                    {
                        var jsonResponse = reader.ReadToEnd();
                        callback?.Invoke(0, jsonResponse);
                    }
                }
            }
            catch (Exception e)
            {
                callback?.Invoke(-1, e.Message);
            }


            yield return null;
        }
    }
}