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src/Jiaowu.Api/Infrastructure/Persistence/AppDbContext.cs

@@ -91,6 +91,9 @@ public sealed class AppDbContext(DbContextOptions<AppDbContext> options)
         Set<GraduationClearanceItem>();
     public DbSet<GraduationClearanceRecord> GraduationClearanceRecords =>
         Set<GraduationClearanceRecord>();
+    public DbSet<OfficialDocument> OfficialDocuments => Set<OfficialDocument>();
+    public DbSet<OfficialDocumentDownload> OfficialDocumentDownloads =>
+        Set<OfficialDocumentDownload>();
     public DbSet<AuditLog> AuditLogs => Set<AuditLog>();
 
     protected override void ConfigureConventions(
@@ -927,6 +930,54 @@ public sealed class AppDbContext(DbContextOptions<AppDbContext> options)
             entity.Property(x => x.IpAddress).HasMaxLength(64);
             entity.HasIndex(x => x.CreatedAt);
         });
+
+        builder.Entity<OfficialDocument>(entity =>
+        {
+            entity.Property(x => x.DocumentNumber).HasMaxLength(50);
+            entity.Property(x => x.VerificationCodeHash).HasMaxLength(64);
+            entity.Property(x => x.Purpose).HasMaxLength(200);
+            entity.Property(x => x.SnapshotJson).HasColumnType("longtext");
+            entity.Property(x => x.PdfContent).HasColumnType("longblob");
+            entity.Property(x => x.PdfSha256).HasMaxLength(64);
+            entity.Property(x => x.InvalidationReason).HasMaxLength(500);
+            entity.HasIndex(x => x.DocumentNumber).IsUnique();
+            entity.HasIndex(x => x.VerificationCodeHash).IsUnique();
+            entity.HasIndex(x => new { x.StudentId, x.IssuedAt });
+            entity.HasIndex(x => new { x.Status, x.IssuedAt });
+            entity.HasOne(x => x.Student)
+                .WithMany()
+                .HasForeignKey(x => x.StudentId)
+                .OnDelete(DeleteBehavior.Restrict);
+            entity.HasOne(x => x.IssuedByUser)
+                .WithMany()
+                .HasForeignKey(x => x.IssuedByUserId)
+                .OnDelete(DeleteBehavior.Restrict);
+            entity.HasOne(x => x.InvalidatedByUser)
+                .WithMany()
+                .HasForeignKey(x => x.InvalidatedByUserId)
+                .OnDelete(DeleteBehavior.Restrict);
+            entity.HasIndex(x => x.ReissuedFromDocumentId).IsUnique();
+            entity.HasOne(x => x.ReissuedFromDocument)
+                .WithMany()
+                .HasForeignKey(x => x.ReissuedFromDocumentId)
+                .OnDelete(DeleteBehavior.Restrict);
+        });
+
+        builder.Entity<OfficialDocumentDownload>(entity =>
+        {
+            entity.Property(x => x.IpAddress).HasMaxLength(64);
+            entity.Property(x => x.UserAgent).HasMaxLength(500);
+            entity.HasIndex(x => new { x.OfficialDocumentId, x.CreatedAt });
+            entity.HasIndex(x => new { x.DownloadedByUserId, x.CreatedAt });
+            entity.HasOne(x => x.OfficialDocument)
+                .WithMany(x => x.Downloads)
+                .HasForeignKey(x => x.OfficialDocumentId)
+                .OnDelete(DeleteBehavior.Cascade);
+            entity.HasOne(x => x.DownloadedByUser)
+                .WithMany()
+                .HasForeignKey(x => x.DownloadedByUserId)
+                .OnDelete(DeleteBehavior.Restrict);
+        });
     }
 
     public override Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)