using FreeTubeSync.Model;
using Microsoft.EntityFrameworkCore;

namespace FreeTubeSync.Database;

public class DataContext : DbContext
{
    public DataContext(DbContextOptions<DataContext> options) : base(options)
    {
        
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        modelBuilder.Entity<Profile>()
            .OwnsMany<Subscription>(o => o.subscriptions);

        modelBuilder.Entity<Playlist>()
            .OwnsMany<Video>(o => o.videos);
    }

    public override int SaveChanges()
    {
        TrackChanges();
        return base.SaveChanges();
    }

    public override async Task<int> SaveChangesAsync(CancellationToken ct = default)
    {
        TrackChanges();
        return await base.SaveChangesAsync(ct);
    }

    private void TrackChanges()
    {
        var changedEntries = ChangeTracker.Entries()
            .Where(e => e.State == EntityState.Added ||
                        e.State == EntityState.Modified ||
                        e.State == EntityState.Deleted)
            .ToList();

        foreach (var entry in changedEntries)
        {
            var log = new ChangeLog
            {
                TableName = entry.Metadata.GetTableName() ?? entry.Entity.GetType().Name,
                ChangeType = entry.State.ToString(),
                ChangeTime = DateTime.UtcNow
            };

            ChangeLogs.Add(log);
        }
    }

    public ChangeLog? GetLatestChange()
    {
        return ChangeLogs
            .OrderByDescending(cl => cl.ChangeTime)
            .FirstOrDefault();
    }

    public async Task<ChangeLog?> GetLatestChangeAsync(CancellationToken ct = default)
    {
        return await ChangeLogs
            .OrderByDescending(cl => cl.ChangeTime)
            .FirstOrDefaultAsync(ct);
    }
    
    public DbSet<History> Histories { get; set; }
    public DbSet<Playlist> Playlists { get; set; }
    public DbSet<Profile> Profiles { get; set; }
    public DbSet<SearchHistory> SearchHistories { get; set; }
    public DbSet<Setting> Settings { get; set; }
    public DbSet<ChangeLog> ChangeLogs { get; set; }
}