using eprintServer.Responses;
using System.Net.Http.Json;

namespace eprintServer.Services;

public class ThawaniServices
{
    private readonly OAuthSettingsService _settingsService;
    private readonly HttpClient _httpClient;

    public ThawaniServices(OAuthSettingsService settingsService, HttpClient httpClient)
    {
        _settingsService = settingsService;
        _httpClient = httpClient;
    }

    public async Task<string> InitiatePayment(object payload)
    {
        var settings = await _settingsService.GetOrCreateSettingsAsync();

        // Validate required attributes for API call
        if (string.IsNullOrWhiteSpace(settings.ThawaniRoot) ||
            string.IsNullOrWhiteSpace(settings.ThawaniApiKey))
        {
            throw new Exception("Thawani configuration error: Root URL or API Key is missing in settings.");
        }

        var url = $"{settings.ThawaniRoot.TrimEnd('/')}/api/v1/checkout/session";

        var request = new HttpRequestMessage(HttpMethod.Post, url);
        request.Headers.Add("thawani-api-key", settings.ThawaniApiKey);
        request.Content = JsonContent.Create(payload);

        var response = await _httpClient.SendAsync(request);
        var result = await response.Content.ReadFromJsonAsync<ThawaniPaymentResponse>();

        if (result != null && result.Success) return result.Data.SessionId;

        throw new Exception($"Thawani Error: {result?.Description ?? "Unknown error during session initiation"}");
    }

    public async Task<string> BuildRedirectUrl(string sessionId)
    {
        var settings = await _settingsService.GetOrCreateSettingsAsync();
        if (settings == null)
        {
            throw new Exception("Thawani configuration not found in the database.");
        }

        // 2. Check if the specific attributes are null or just empty spaces
        if (string.IsNullOrWhiteSpace(settings.ThawaniCheckoutModelUrl) ||
            string.IsNullOrWhiteSpace(settings.ThawaniPublicKey))
        {
            throw new Exception("Thawani configuration is incomplete: Checkout URL or Public Key is missing.");
        }
        var baseUrl = settings.ThawaniCheckoutModelUrl.Trim().TrimEnd('/');
        var publicKey = settings.ThawaniPublicKey.Trim();

        // Standard Thawani format (UAT often uses /checkout/ instead of /pay/)
        return $"{baseUrl}/pay/{sessionId}?key={publicKey}";
    }

    public async Task<ThawaniPaymentResponse> GetSession(string sessionId)
    {
        var settings = await _settingsService.GetOrCreateSettingsAsync();

        if (string.IsNullOrWhiteSpace(settings.ThawaniRoot) || string.IsNullOrWhiteSpace(settings.ThawaniApiKey))
        {
            throw new Exception("Thawani configuration error: Root URL or API Key is missing.");
        }

        // URL: https://uatcheckout.thawani.om/api/v1/checkout/session/{sessionId}
        var url = $"{settings.ThawaniRoot.TrimEnd('/')}/api/v1/checkout/session/{sessionId}";

        var request = new HttpRequestMessage(HttpMethod.Get, url);
        request.Headers.Add("thawani-api-key", settings.ThawaniApiKey);

        var response = await _httpClient.SendAsync(request);

        if (!response.IsSuccessStatusCode)
        {
            return null;
        }

        return await response.Content.ReadFromJsonAsync<ThawaniPaymentResponse>();
    }
}