// FlashMdService.cs
using System.Net.Http.Headers;
using System.Text.Json;

public class FlashMdService
{
    private readonly HttpClient _http;
    private readonly string _apiUrl;
    private readonly string _apiKey;

    public FlashMdService(HttpClient http, IConfiguration config)
    {
        _http = http;
        _apiUrl = config["FlashMd:ApiUrl"]!;
        _apiKey = config["FlashMd:ApiKey"]!;
    }

    public async Task<string> ConvertAsync(Stream fileStream, string filename, string contentType)
    {
        var content = new StreamContent(fileStream);
        content.Headers.ContentType = new MediaTypeHeaderValue(contentType);

        var request = new HttpRequestMessage(HttpMethod.Post,
            $"{_apiUrl}/convert/raw?filename={Uri.EscapeDataString(filename)}&mode=fast");
        request.Headers.Add("x-api-key", _apiKey);
        request.Content = content;

        var res = await _http.SendAsync(request);

        if (res.StatusCode == System.Net.HttpStatusCode.OK)
            return await res.Content.ReadAsStringAsync();

        if ((int)res.StatusCode == 202)
        {
            var json = JsonDocument.Parse(await res.Content.ReadAsStringAsync());
            var jobId = json.RootElement.GetProperty("job_id").GetString()!;
            return await PollJobAsync(jobId);
        }

        res.EnsureSuccessStatusCode();
        return "";
    }

    private async Task<string> PollJobAsync(string jobId)
    {
        while (true)
        {
            await Task.Delay(5000);

            var request = new HttpRequestMessage(HttpMethod.Get, $"{_apiUrl}/jobs/{jobId}");
            request.Headers.Add("x-api-key", _apiKey);
            var res = await _http.SendAsync(request);
            var json = JsonDocument.Parse(await res.Content.ReadAsStringAsync());
            var status = json.RootElement.GetProperty("status").GetString();

            if (status == "completed")
                return json.RootElement.GetProperty("body").GetString()!;
            if (status == "failed")
                throw new Exception(json.RootElement.GetProperty("error").GetString());
        }
    }
}

// Program.cs
builder.Services.AddHttpClient<FlashMdService>();

app.MapPost("/api/convert", async (IFormFile file, FlashMdService flash) =>
{
    using var stream = file.OpenReadStream();
    var markdown = await flash.ConvertAsync(stream, file.FileName, file.ContentType);
    return Results.Text(markdown, "text/markdown");
});

// appsettings.json
{
  "FlashMd": {
    "ApiUrl": "https://api.markpdf.tech",
    "ApiKey": ""
  }
}