using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Logging;

namespace TentacleBot.Services;

public class PalworldApiService
{
    private readonly HttpClient _httpClient;
    private readonly ILogger<PalworldApiService> _logger;
    private readonly string _baseUrl;

    public PalworldApiService(
        IHttpClientFactory httpClientFactory,
        IConfiguration configuration,
        ILogger<PalworldApiService> logger)
    {
        _httpClient = httpClientFactory.CreateClient("PalworldApi");
        _logger = logger;

        _baseUrl = configuration["Palworld:BaseUrl"]
            ?? throw new InvalidOperationException("Palworld:BaseUrl not configured");

        var username = configuration["Palworld:Username"] ?? "admin";
        var password = Environment.GetEnvironmentVariable("PALWORLD_PASSWORD")
            ?? throw new InvalidOperationException("PALWORLD_PASSWORD environment variable is not set");

        var credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes($"{username}:{password}"));
        _httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Basic", credentials);
        _httpClient.Timeout = TimeSpan.FromSeconds(10);
    }

    public async Task<JsonDocument?> GetInfoAsync()
    {
        return await GetAsync("info");
    }

    public async Task<JsonDocument?> GetPlayersAsync()
    {
        return await GetAsync("players");
    }

    public async Task<JsonDocument?> GetMetricsAsync()
    {
        return await GetAsync("metrics");
    }

    private async Task<JsonDocument?> GetAsync(string endpoint)
    {
        try
        {
            var url = $"{_baseUrl.TrimEnd('/')}/v1/api/{endpoint}";
            var response = await _httpClient.GetAsync(url);

            if (response.StatusCode == System.Net.HttpStatusCode.Unauthorized)
            {
                _logger.LogError("Palworld API returned 401 Unauthorized. Check your Palworld:Username and Palworld:Password config.");
                return null;
            }

            response.EnsureSuccessStatusCode();

            var json = await response.Content.ReadAsStringAsync();
            return JsonDocument.Parse(json);
        }
        catch (TaskCanceledException)
        {
            _logger.LogError("Palworld API request timed out at {Endpoint}", endpoint);
            return null;
        }
        catch (HttpRequestException ex)
        {
            _logger.LogError(ex, "HTTP error calling Palworld API {Endpoint}", endpoint);
            return null;
        }
        catch (JsonException ex)
        {
            _logger.LogError(ex, "Failed to parse Palworld API response from {Endpoint}", endpoint);
            return null;
        }
    }
}