using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;

namespace ScoreTracker.API
{
    internal class Request
    {
        private static readonly HttpClient client = new HttpClient();

        private class AuthHelper
        {
            public bool IsLoggedIn;
            public string FailReason = "";

            public async Task EnsureLoggedIn()
            {
                if (Authentication.IsSignedIn() && await Authentication.ValidateAuthToken())
                {
                    return; // Already logged in with a valid token
                }

                await Authentication.LoginUser(
                    token => {
                        IsLoggedIn = true;
                        PersistHeaders(new Dictionary<string, string>
                        {
                            { "Authorization", $"Bearer {token}" }
                        });
                    },
                    reason =>
                    {
                        FailReason = reason; // Store the reason for failure
                        client.DefaultRequestHeaders.Clear(); // Clear headers
                    }
                );
            }
        }

        /// <summary>
        /// Persist the given headers for all future requests
        /// </summary>
        /// <param name="headers">the headers to persist</param>
        public static void PersistHeaders(Dictionary<string, string> headers)
        {
            client.DefaultRequestHeaders.Clear(); // Clear existing headers
            foreach (var header in headers)
            {
                client.DefaultRequestHeaders.Add(header.Key, header.Value);
            }
        }

        /// <summary>
        /// Create a POST request to the given URL with the given data
        /// </summary>
        /// <param name="url">the url to post to</param>
        /// <param name="data">the data to post</param>
        /// <param name="checkAuth">whether to check for authentication</param>
        /// <returns>the task</returns>
        public static async Task<HttpResponseMessage> PostJsonAsync(string url, Dictionary<object, object> json, bool checkAuth = true)
        {
            if (checkAuth)
            {
                var authHelper = new AuthHelper();
                await authHelper.EnsureLoggedIn();
                if (!authHelper.IsLoggedIn)
                {
                    throw new Exception($"Failed to log in: {authHelper.FailReason}");
                }
            }
            var jsonString = JsonConvert.SerializeObject(json, Formatting.None);
            var content = new StringContent(jsonString, Encoding.UTF8, "application/json");

            // Send the POST request
            var response = await client.PostAsync(url, content);
            return response;
        }
    }
}