using System.Text.Json;
using System.Text.Json.Serialization;
using Nuuru.Server.Models;

namespace Nuuru.Server.Services
{
    public class HCaptchaService : ICaptchaService
    {
        private readonly ILogger<HCaptchaService> _logger;
        private readonly ISiteSettingsService _siteSettings;
        private readonly HttpClient _httpClient;

        public HCaptchaService(ILogger<HCaptchaService> logger, ISiteSettingsService siteSettings, IHttpClientFactory httpClientFactory)
        {
            _logger = logger;
            _siteSettings = siteSettings;
            _httpClient = httpClientFactory.CreateClient();
        }

        public async Task<bool> ValidateAsync(string token)
        {
            var secretKey = await _siteSettings.GetCaptchaSettingAsync(
                SiteSettingKeys.CaptchaHCaptchaSecretKey, "");

            if (string.IsNullOrEmpty(secretKey))
            {
                _logger.LogError("HCaptcha secret key is not configured");
                return false;
            }

            if (string.IsNullOrEmpty(token))
            {
                _logger.LogWarning("CAPTCHA token is empty");
                return false;
            }

            try
            {
                var verifyUrl = await _siteSettings.GetCaptchaSettingAsync(
                    SiteSettingKeys.CaptchaHCaptchaVerifyUrl,
                    SiteSettingKeys.DefaultCaptchaHCaptchaVerifyUrl);

                var formData = new Dictionary<string, string>
                {
                    { "secret", secretKey },
                    { "response", token }
                };

                var response = await _httpClient.PostAsync(verifyUrl, new FormUrlEncodedContent(formData));
                var responseContent = await response.Content.ReadAsStringAsync();

                var result = JsonSerializer.Deserialize<HCaptchaResponse>(responseContent, new JsonSerializerOptions
                {
                    PropertyNameCaseInsensitive = true
                });

                if (result?.Success == true)
                {
                    _logger.LogInformation("CAPTCHA validation successful");
                    return true;
                }

                _logger.LogWarning("CAPTCHA validation failed: {ErrorCodes}",
                    result?.ErrorCodes != null ? string.Join(", ", result.ErrorCodes) : "Unknown error");
                return false;
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Error validating CAPTCHA");
                return false;
            }
        }

        private class HCaptchaResponse
        {
            [JsonPropertyName("success")]
            public bool Success { get; set; }

            [JsonPropertyName("challenge_ts")]
            public string? ChallengeTs { get; set; }

            [JsonPropertyName("hostname")]
            public string? Hostname { get; set; }

            [JsonPropertyName("error-codes")]
            public string[]? ErrorCodes { get; set; }
        }
    }
}