ersatztv/ErsatzTV/Controllers/Api/ChannelController.cs

using System.ComponentModel.DataAnnotations;
using System.Threading.Channels;
using ErsatzTV.Application;
using ErsatzTV.Application.Channels;
using ErsatzTV.Application.Playouts;
using ErsatzTV.Controllers.Api.Requests;
using ErsatzTV.Core;
using ErsatzTV.Core.Api.Channels;
using ErsatzTV.Core.Domain;
using ErsatzTV.Core.Scheduling;
using ErsatzTV.Extensions;
using MediatR;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;

namespace ErsatzTV.Controllers.Api;

[ApiController]
public class ChannelController(ChannelWriter<IBackgroundServiceRequest> workerChannel, IMediator mediator)
{
    [HttpGet("/api/channels")]
    [EndpointGroupName("general")]
    public async Task<List<ChannelResponseModel>> GetAll() => await mediator.Send(new GetAllChannelsForApi());

    [HttpGet("/api/channels/{id:int}", Name = "GetChannelById")]
    [Tags("Channels")]
    [EndpointSummary("Get a channel by id")]
    [EndpointGroupName("general")]
    [ProducesResponseType(typeof(ChannelViewModel), StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status404NotFound)]
    public async Task<IActionResult> GetById(int id, CancellationToken cancellationToken)
    {
        Option<ChannelViewModel> result = await mediator.Send(new GetChannelById(id), cancellationToken);
        return result.ToGetResult();
    }

    [HttpPost("/api/channels")]
    [Tags("Channels")]
    [EndpointSummary("Create a channel")]
    [EndpointGroupName("general")]
    [ProducesResponseType(typeof(ChannelViewModel), StatusCodes.Status201Created)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status404NotFound)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status422UnprocessableEntity)]
    public async Task<IActionResult> Create(
        [Required] [FromBody] CreateChannelRequest request,
        CancellationToken cancellationToken)
    {
        Either<BaseError, CreateChannelResult> result = await mediator.Send(request.ToCommand(), cancellationToken);
        return await result.Match(
            Left: error => Task.FromResult(error.ToErrorResult()),
            Right: async created =>
            {
                Option<ChannelViewModel> channel =
                    await mediator.Send(new GetChannelById(created.ChannelId), cancellationToken);
                return channel.Match(
                    Some: vm => (IActionResult)new CreatedResult($"/api/channels/{vm.Id}", vm),
                    None: () => ApiResults.NotFoundProblem());
            });
    }

    [HttpPut("/api/channels/{id:int}")]
    [Tags("Channels")]
    [EndpointSummary("Update a channel")]
    [EndpointGroupName("general")]
    [ProducesResponseType(typeof(ChannelViewModel), StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status404NotFound)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status422UnprocessableEntity)]
    public async Task<IActionResult> Update(
        int id,
        [Required] [FromBody] UpdateChannelRequest request,
        CancellationToken cancellationToken)
    {
        Either<BaseError, ChannelViewModel> result =
            await mediator.Send(request.ToCommand(id), cancellationToken);
        return result.ToUpdatedResult();
    }

    [HttpDelete("/api/channels/{id:int}")]
    [Tags("Channels")]
    [EndpointSummary("Delete a channel")]
    [EndpointGroupName("general")]
    [ProducesResponseType(StatusCodes.Status204NoContent)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status404NotFound)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status422UnprocessableEntity)]
    public async Task<IActionResult> Delete(int id, CancellationToken cancellationToken)
    {
        Either<BaseError, Unit> result = await mediator.Send(new DeleteChannel(id), cancellationToken);
        return result.ToDeletedResult();
    }

    [HttpPost("/api/channels/{channelNumber}/playout/reset")]
    [Tags("Channels")]
    [EndpointSummary("Reset channel playout")]
    [EndpointDescription(
        "When mode is omitted, classic playouts use Refresh (rebuild while maintaining collection " +
        "progress) and all other playout kinds use Reset (rebuild from scratch), matching the Blazor UI. " +
        "Pass mode to force a specific PlayoutBuildMode.")]
    [EndpointGroupName("general")]
    [ProducesResponseType(StatusCodes.Status200OK)]
    [ProducesResponseType(typeof(ProblemDetails), StatusCodes.Status404NotFound)]
    public async Task<IActionResult> ResetPlayout(
        string channelNumber,
        [FromQuery] PlayoutBuildMode? mode,
        CancellationToken cancellationToken)
    {
        Option<int> maybePlayoutId =
            await mediator.Send(new GetPlayoutIdByChannelNumber(channelNumber), cancellationToken);
        foreach (int playoutId in maybePlayoutId)
        {
            PlayoutBuildMode buildMode = mode ?? await DefaultResetMode(playoutId, cancellationToken);
            await workerChannel.WriteAsync(new BuildPlayout(playoutId, buildMode), cancellationToken);
            return new OkResult();
        }

        return ApiResults.NotFoundProblem();
    }

    // Match Blazor's Playouts.razor reset semantics: classic playouts refresh (preserve progress),
    // every other kind resets from scratch.
    private async Task<PlayoutBuildMode> DefaultResetMode(int playoutId, CancellationToken cancellationToken)
    {
        Option<PlayoutNameViewModel> maybePlayout =
            await mediator.Send(new GetPlayoutById(playoutId), cancellationToken);
        return maybePlayout.Match(
            Some: vm => vm.ScheduleKind switch
            {
                PlayoutScheduleKind.Classic => PlayoutBuildMode.Refresh,
                _ => PlayoutBuildMode.Reset
            },
            None: () => PlayoutBuildMode.Reset);
    }
}