telegram-bot/modules/ChatQuotes/QuoteGeneratorService.cs

using System.Net.Http.Headers;
using System.Text;
using Microsoft.Extensions.Configuration;
using Newtonsoft.Json;
using Telegram.Bot.Types;
using West.TelegramBot.ChatQuotes.Model;
using West.TelegramBot.ChatQuotes.Model.Quote;
using Message = Telegram.Bot.Types.Message;

namespace West.TelegramBot.ChatQuotes;

public class QuoteGeneratorService
{
    private readonly HttpClient _httpClient;
    private readonly MediaTypeHeaderValue _mediaType;

    public QuoteGeneratorService(IConfiguration configuration)
    {
        _httpClient = new HttpClient
        {
            BaseAddress = new Uri(configuration.GetValue<string>("QuoteApiUrl"))
        };

        _mediaType = MediaTypeHeaderValue.Parse("application/json");
    }

    public async Task<Stream?> GenerateQuoteImage(Message msg)
    {
        var request = new Request(msg);
        var content = new ByteArrayContent(Encoding.UTF8.GetBytes(request.ToJson().ToCharArray()))
        {
            Headers =
            {
                ContentType = _mediaType
            }
        };

        var resp = await _httpClient.PostAsync("/generate", content);
        var quoteResponse = JsonConvert.DeserializeObject<Response>(await resp.Content.ReadAsStringAsync());

        return quoteResponse.Ok ? new MemoryStream(Convert.FromBase64String(quoteResponse.Result.Image)) : null;
    }
}