changes

Data/ApplicationDbContext.cs

@@ -0,0 +1,56 @@
+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();
+            });
+        }
+    }
+}