using LiteCqrs;
using Microsoft.EntityFrameworkCore;
using TeleWave.Application.Common.Interfaces;
using TeleWave.Application.Common.Models;

namespace TeleWave.Application.Broadcast.Bumpers;

public sealed class RemoveBumperTextVariantCommandHandler(IAppDbContext dbContext)
    : ICommandHandler<RemoveBumperTextVariantCommand, Result>
{
    public async Task<Result> Handle(
        RemoveBumperTextVariantCommand command,
        CancellationToken cancellationToken
    )
    {
        var channel = await dbContext
            .Channels.Include(c => c.BumperTemplates)
                .ThenInclude(t => t.Variants)
            .AsSplitQuery()
            .FirstOrDefaultAsync(c => c.Id == command.ChannelId, cancellationToken);
        if (channel is null)
            return Result.Failure(ChannelErrors.NotFound);

        var template = channel.FindBumperTemplate(command.TemplateId);
        if (template is null)
            return Result.Failure(ChannelErrors.BumperTemplateNotFound);
        if (template.FindVariant(command.VariantId) is null)
            return Result.Failure(ChannelErrors.BumperTextVariantNotFound);

        return template.RemoveVariant(command.VariantId)
            ? Result.Success()
            : Result.Failure(ChannelErrors.CannotRemoveLastBumperTextVariant);
    }
}
