using Mediator;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using Musify.Application.Contracts;
using Musify.Application.Mixes;

namespace Musify.Infrastructure.Jobs;

public class DailyMixGenerationJob(
    IDatabase database,
    IMediator mediator,
    ILogger<DailyMixGenerationJob> logger)
{
    public async Task RunAsync(CancellationToken cancellationToken)
    {
        var userIds = await database.ListeningHistories
            .AsNoTracking()
            .Where(history => history.IsCounted)
            .Select(history => history.UserId)
            .Distinct()
            .ToListAsync(cancellationToken);

        logger.LogInformation("Starting daily mix generation for {Count} users", userIds.Count);

        foreach (var userId in userIds)
        {
            var result = await mediator.Send(new GenerateMixesForUserCommand(userId), cancellationToken);
            if (result.IsError)
            {
                logger.LogWarning("Failed to generate mixes for user {UserId}: {Error}",
                    userId, result.FirstError.Description);
            }
        }

        logger.LogInformation("Finished daily mix generation");
    }
}