using ErsatzTV.Core.Domain;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata.Builders;

namespace ErsatzTV.Infrastructure.Data.Configurations;

public class LibraryFolderConfiguration : IEntityTypeConfiguration<LibraryFolder>
{
    public void Configure(EntityTypeBuilder<LibraryFolder> builder)
    {
        builder.ToTable("LibraryFolder");

        // ersatztv#491: GetOrAddFolder is a check-then-insert, so two callers racing the same folder both
        // miss the lookup and both insert. The unique index makes the duplicate impossible at the storage
        // layer (the loser gets a constraint violation the repository catches and re-reads).
        // Indexed on PathHash rather than Path because Path is unbounded (MySQL longtext, which cannot be
        // indexed without a prefix length, and whose default collation is case-INsensitive — a prefix
        // index would also false-collide sibling folders differing only in case on a case-sensitive
        // filesystem). This mirrors the existing MediaFile.Path/PathHash pair.
        builder.Property(f => f.PathHash)
            .HasMaxLength(64);

        builder.HasIndex(f => new { f.LibraryPathId, f.PathHash })
            .IsUnique();

        builder.HasOne(f => f.Parent)
            .WithMany(p => p.Children)
            .HasForeignKey(f => f.ParentId)
            .IsRequired(false)
            .OnDelete(DeleteBehavior.Restrict);

        builder.HasOne(f => f.ImageFolderDuration)
            .WithOne(ifd => ifd.LibraryFolder)
            .HasForeignKey<ImageFolderDuration>(ifd => ifd.LibraryFolderId)
            .IsRequired(false)
            .OnDelete(DeleteBehavior.Cascade);
    }
}