public-valetax/Data/ApplicationDbContext.cs

using Microsoft.EntityFrameworkCore;
using public_valetax.Models;

namespace public_valetax.Data
{
    public class ApplicationDbContext(DbContextOptions<ApplicationDbContext> options) : DbContext(options)
    {
        public DbSet<Tree> Trees { get; set; } = null!;
        public DbSet<Node> Nodes { get; set; } = null!;
        public DbSet<JournalEntry> JournalEntries { get; set; } = null!;

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);

            // Configure Tree entity
            modelBuilder.Entity<Tree>(entity =>
            {
                entity.HasKey(e => e.Id);
                entity.Property(e => e.Name).IsRequired().HasMaxLength(255);
                entity.HasIndex(e => e.Name).IsUnique();
            });

            // Configure Node entity
            modelBuilder.Entity<Node>(entity =>
            {
                entity.HasKey(e => e.Id);
                entity.Property(e => e.Name).IsRequired().HasMaxLength(255);
                
                // Self-referencing foreign key for parent-child relationship
                entity.HasOne(n => n.Parent)
                    .WithMany(n => n.Children)
                    .HasForeignKey(n => n.ParentId)
                    .OnDelete(DeleteBehavior.Cascade);
                
                // Foreign key to Tree
                entity.HasOne(n => n.Tree)
                    .WithMany(t => t.Nodes)
                    .HasForeignKey(n => n.TreeId)
                    .OnDelete(DeleteBehavior.Cascade);
                
                // Ensure unique node names within the same tree
                entity.HasIndex(n => new { n.TreeId, n.Name }).IsUnique();
            });

            // Configure JournalEntry entity
            modelBuilder.Entity<JournalEntry>(entity =>
            {
                entity.HasKey(e => e.Id);
                entity.Property(e => e.ExceptionType).IsRequired().HasMaxLength(255);
                entity.Property(e => e.Message).IsRequired();
                entity.HasIndex(e => e.EventId).IsUnique();
            });
        }
    }
}