Relay/RelayServer/Endpoints/RtcEndpoints.cs

using System.Text.Json;
using RelayShared.Rtc;
using RelayServer.Services.Rtc;

namespace RelayServer.Endpoints;

public static class RtcEndpoints
{
    public static void MapRtcEndpoints(this WebApplication app)
    {
        app.MapPost("/api/rtc/offer", async (RtcOffer request, RtcCallService rtcCallService) =>
        {
            await rtcCallService.WriteOfferAsync(
                request.ChannelId,
                request.Username,
                request.TargetUsername,
                request.SessionDescription);

            RtcNotificationService.BroadcastToChannel(new RtcNotificationMessage
            {
                Type = SignalType.OfferUpdated,
                ChannelId = request.ChannelId,
                Username = request.Username,
                TargetUsername = request.TargetUsername
            });

            return Results.Ok();
        });

        app.MapGet("/api/rtc/offers", async (RtcCallService rtcCallService) =>
        {
            return Results.Ok(await rtcCallService.GetOffersAsync());
        });

        app.MapGet("/api/rtc/active/{channelId}", async (string channelId, RtcCallService rtcCallService) =>
        {
            return Results.Ok(await rtcCallService.HasActiveCallAsync(channelId));
        });

        app.MapGet("/api/rtc/participants/{channelId}", async (string channelId, RtcCallService rtcCallService) =>
        {
            return Results.Ok(await rtcCallService.GetParticipantsAsync(channelId));
        });

        app.MapGet("/api/rtc/offer/{channelId}/{fromUsername}/{targetUsername}", async (
            string channelId,
            string fromUsername,
            string targetUsername,
            RtcCallService rtcCallService) =>
        {
            var offer = await rtcCallService.GetOfferAsync(channelId, fromUsername, targetUsername);
            return offer is null ? Results.NotFound() : Results.Ok(offer);
        });

        app.MapPost("/api/rtc/answer", async (RtcAnswer request, RtcCallService rtcCallService) =>
        {
            await rtcCallService.WriteAnswerAsync(
                request.ChannelId,
                request.Username,
                request.TargetUsername,
                request.SessionDescription);

            RtcNotificationService.BroadcastToChannel(new RtcNotificationMessage
            {
                Type = SignalType.AnswerUpdated,
                ChannelId = request.ChannelId,
                Username = request.Username,
                TargetUsername = request.TargetUsername
            });

            return Results.Ok();
        });

        app.MapGet("/api/rtc/answer/{channelId}/{fromUsername}/{targetUsername}", async (
            string channelId,
            string fromUsername,
            string targetUsername,
            RtcCallService rtcCallService) =>
        {
            var answer = await rtcCallService.GetAnswerAsync(channelId, fromUsername, targetUsername);
            return answer is null ? Results.NotFound() : Results.Ok(answer);
        });

        app.MapPost("/api/rtc/candidate", async (DBIceCandidate request, RtcCallService rtcCallService) =>
        {
            await rtcCallService.WriteIceCandidateAsync(
                request.ChannelId,
                request.Username,
                request.TargetUsername,
                request.Candidate.candidate,
                request.Candidate.sdpMid,
                request.Candidate.sdpMLineIndex);

            RtcNotificationService.BroadcastToChannel(new RtcNotificationMessage
            {
                Type = SignalType.CandidateAdded,
                ChannelId = request.ChannelId,
                Username = request.Username,
                TargetUsername = request.TargetUsername,
                Direction = JsonSerializer.Serialize(request.Candidate)
            });

            return Results.Ok();
        });

        app.MapGet("/api/rtc/candidates/{channelId}", async (string channelId, RtcCallService rtcCallService) =>
        {
            return Results.Ok(await rtcCallService.GetIceCandidatesAsync(channelId));
        });

        app.MapPost("/api/rtc/leave", async (RtcLeaveRequest request, RtcCallService rtcCallService) =>
        {
            await rtcCallService.LeaveCallAsync(request.ChannelId, request.Username);

            RtcNotificationService.BroadcastToChannel(new RtcNotificationMessage
            {
                Type = SignalType.CallLeft,
                ChannelId = request.ChannelId,
                Username = request.Username
            });

            return Results.Ok();
        });
    }
}