using System.Net;
using System.Net.Http.Json;
using System.Text.Json.Serialization;
using MMOserver.Utils;
using Serilog;

namespace MMOserver.Api;

public class RestApi : Singleton<RestApi>
{
    private const string VERIFY_URL = "https://a301.api.tolelom.xyz";
    private const string INTERNAL_API_KEY = "017f15b28143fc67d2e5bed283c37d2da858b9f294990a5334238e055e3f5425";
    private readonly HttpClient httpClient = new HttpClient { Timeout = TimeSpan.FromSeconds(5) };

    private const int MAX_RETRY = 3;
    private static readonly TimeSpan RETRY_DELAY = TimeSpan.FromSeconds(1);

    public RestApi()
    {
        httpClient.DefaultRequestHeaders.Add("X-API-Key", INTERNAL_API_KEY);
    }

    // 토큰 검증 - 성공 시 username 반환
    // 401 → 재시도 없이 즉시 null 반환 (토큰 자체가 무효)
    // 타임아웃/네트워크 오류 → 최대 MAX_RETRY회 재시도 후 null 반환
    public async Task<string?> VerifyTokenAsync(string token)
    {
        string url = VERIFY_URL + "/api/internal/auth/verify";
        for (int attempt = 1; attempt <= MAX_RETRY; attempt++)
        {
            try
            {
                HttpResponseMessage response = await httpClient.PostAsJsonAsync(url, new { token });

                // 401: 토큰 자체가 무효 → 재시도해도 같은 결과, 즉시 반환
                if (response.StatusCode == HttpStatusCode.Unauthorized)
                {
                    Log.Warning("[RestApi] 토큰 인증 실패 (401)");
                    return null;
                }

                response.EnsureSuccessStatusCode();

                AuthVerifyResponse? result = await response.Content.ReadFromJsonAsync<AuthVerifyResponse>();
                return result?.Username;
            }
            catch (Exception ex) when (attempt < MAX_RETRY)
            {
                // 일시적 장애 (타임아웃, 네트워크 오류 등) → 재시도
                Log.Warning("[RestApi] 통신 실패 (시도 {Attempt}/{Max}): {Message}", attempt, MAX_RETRY, ex.Message);
                await Task.Delay(RETRY_DELAY);
            }
            catch (Exception ex)
            {
                // 마지막 시도까지 실패
                Log.Error("[RestApi] 최종 통신 실패 ({Max}회 시도): {Message}", MAX_RETRY, ex.Message);
            }
        }

        return null;
    }

    // 플레이어 프로필 조회 - 성공 시 PlayerProfileResponse 반환
    public async Task<PlayerProfileResponse?> GetPlayerProfileAsync(string username)
    {
        string url = VERIFY_URL + "/api/internal/player/profile?username=" + Uri.EscapeDataString(username);
        for (int attempt = 1; attempt <= MAX_RETRY; attempt++)
        {
            try
            {
                HttpResponseMessage response = await httpClient.GetAsync(url);
                if (response.StatusCode == HttpStatusCode.NotFound)
                {
                    Log.Warning("[RestApi] 프로필 없음 username={Username}", username);
                    return null;
                }

                response.EnsureSuccessStatusCode();
                return await response.Content.ReadFromJsonAsync<PlayerProfileResponse>();
            }
            catch (Exception ex) when (attempt < MAX_RETRY)
            {
                Log.Warning("[RestApi] 프로필 조회 실패 (시도 {Attempt}/{Max}): {Message}", attempt, MAX_RETRY, ex.Message);
                await Task.Delay(RETRY_DELAY);
            }
            catch (Exception ex)
            {
                Log.Error("[RestApi] 프로필 조회 최종 실패 ({Max}회 시도): {Message}", MAX_RETRY, ex.Message);
            }
        }

        return null;
    }

    private sealed class AuthVerifyResponse
    {
        [JsonPropertyName("username")]
        public string? Username
        {
            get;
            set;
        }
    }

    public sealed class PlayerProfileResponse
    {
        [JsonPropertyName("nickname")]
        public string Nickname { get; set; } = string.Empty;

        [JsonPropertyName("level")]
        public int Level { get; set; }

        [JsonPropertyName("experience")]
        public int Experience { get; set; }

        [JsonPropertyName("nextExp")]
        public int NextExp { get; set; }

        [JsonPropertyName("maxHp")]
        public double MaxHp { get; set; }

        [JsonPropertyName("maxMp")]
        public double MaxMp { get; set; }

        [JsonPropertyName("attackPower")]
        public double AttackPower { get; set; }

        [JsonPropertyName("attackRange")]
        public double AttackRange { get; set; }

        [JsonPropertyName("sprintMultiplier")]
        public double SprintMultiplier { get; set; }
    }
}