using System.Text;

namespace DeepDrftPublic.Client.Services;

/// <summary>
/// Production <see cref="IEventPoster"/>: a first-party, same-origin <see cref="System.Net.Http.HttpClient"/>
/// POST to the site's own <c>api/event/*</c> proxy (telemetry transport-resilience). A fetch to the host's
/// own origin is not third-party tracking and is not caught by the name-based heuristics (Firefox
/// Fingerprinting / Tracking Protection) that block a <c>telemetry/beacon</c>-named <c>sendBeacon</c>
/// module. Used for the awaitable play-close paths (organic end / track-switch / stop) and every share
/// event; only the rare tab-unload edge still goes through <see cref="BeaconInterop"/>, where an awaited
/// fetch would be cancelled as the page freezes.
///
/// <para>Best-effort and non-throwing by contract: a failed POST (offline, blocked, server error) is
/// swallowed so a dropped telemetry event never throws into the UI or the playback path — identical
/// posture to the beacon transport.</para>
/// </summary>
public sealed class HttpEventPoster : IEventPoster
{
    // The default factory client carries no base address; the sink/tracker pass an absolute same-origin
    // URL built from NavigationManager.BaseUri, so the POST targets the host proxy regardless of how the
    // named clients are configured. The default client uses the browser fetch handler in WASM, which is
    // exactly the first-party request the heuristic blockers permit.
    private readonly IHttpClientFactory _httpClientFactory;

    public HttpEventPoster(IHttpClientFactory httpClientFactory)
    {
        _httpClientFactory = httpClientFactory;
    }

    public async Task PostAsync(string url, string json)
    {
        try
        {
            using var client = _httpClientFactory.CreateClient();
            using var content = new StringContent(json, Encoding.UTF8, "application/json");
            // Best-effort: the server records the event; we do not act on the status either way.
            using var response = await client.PostAsync(url, content);
        }
        catch
        {
            // Swallow — a dropped telemetry event is acceptable; telemetry must never throw into the UI
            // or the playback path. Mirrors the beacon's fire-and-forget contract.
        }
    }
}