using System.Net.Http.Json;
using System.Text.Json;
using EnvelopeGenerator.Application.Common.Dto;

namespace EnvelopeGenerator.Server.Client.Services;

public class PdfRenderService(IHttpClientFactory httpClientFactory)
{
    private static readonly JsonSerializerOptions _jsonOptions = new(JsonSerializerDefaults.Web);

    public async Task<IReadOnlyList<PdfPageImageDto>> RenderPagesAsync(byte[] pdfBytes, CancellationToken cancel = default)
    {
        using var http = httpClientFactory.CreateClient("EnvelopeGenerator.Server");
        using var response = await http.PostAsJsonAsync(
            "/api/PdfRender/pages",
            new PdfRenderRequestDto { PdfBytes = pdfBytes },
            _jsonOptions,
            cancel);

        if (!response.IsSuccessStatusCode)
        {
            var statusCode = (int)response.StatusCode;
            var reasonPhrase = response.ReasonPhrase ?? "Unknown error";
            throw new HttpRequestException(
                $"Failed to render PDF pages. Status: {statusCode} ({reasonPhrase})",
                null,
                response.StatusCode);
        }

        return await response.Content.ReadFromJsonAsync<List<PdfPageImageDto>>(_jsonOptions, cancel) ?? [];
    }
}