// ============================================================
// PGVECTOR ENTITY + CONFIGURATION TEMPLATE
// Generated by MORPH Framework
// ============================================================

using System.ComponentModel.DataAnnotations.Schema;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata.Builders;
using Pgvector;

#nullable disable

namespace {{NAMESPACE}}.Domain.Entities;

/// <summary>
/// Entity with vector embedding for similarity search via pgvector.
/// Dimensions: 1536 (text-embedding-3-small). Adjust if using a different model.
/// </summary>
public class {{pascalCase FEATURE_NAME}}
{
    public Guid Id { get; set; }
    public string Title { get; set; } = string.Empty;
    public string Content { get; set; } = string.Empty;
    public string? Metadata { get; set; }

    [Column(TypeName = "vector(1536)")]
    public Vector? Embedding { get; set; }

    public DateTimeOffset CreatedAt { get; set; } = DateTimeOffset.UtcNow;
    public DateTimeOffset? UpdatedAt { get; set; }
}

// ============================================================
// ENTITY TYPE CONFIGURATION
// ============================================================

namespace {{NAMESPACE}}.Infrastructure.Data.Configurations;

public class {{pascalCase FEATURE_NAME}}Configuration : IEntityTypeConfiguration<{{pascalCase FEATURE_NAME}}>
{
    public void Configure(EntityTypeBuilder<{{pascalCase FEATURE_NAME}}> builder)
    {
        builder.ToTable("{{snakeCase FEATURE_NAME}}s");
        builder.HasKey(e => e.Id);
        builder.Property(e => e.Id).HasDefaultValueSql("gen_random_uuid()");
        builder.Property(e => e.Title).IsRequired().HasMaxLength(200);
        builder.Property(e => e.Content).IsRequired();
        builder.Property(e => e.Metadata).HasColumnType("jsonb");
        builder.Property(e => e.Embedding).HasColumnType("vector(1536)");
        builder.Property(e => e.CreatedAt).HasDefaultValueSql("now()");

        // HNSW index for cosine similarity search
        builder.HasIndex(e => e.Embedding)
            .HasMethod("hnsw")
            .HasOperators("vector_cosine_ops")
            .HasStorageParameter("m", 16)
            .HasStorageParameter("ef_construction", 64);

        builder.HasIndex(e => e.Title);
    }
}

// ============================================================
// SETUP INSTRUCTIONS
// ============================================================
//
// 1. Install NuGet packages:
//
//    dotnet add package Pgvector.EntityFrameworkCore
//    dotnet add package Npgsql.EntityFrameworkCore.PostgreSQL
//
// 2. Configure NpgsqlDataSource with vector support in Program.cs:
//
//    builder.Services.AddNpgsql<AppDbContext>(
//        connectionString,
//        npgsqlOptions => npgsqlOptions.UseVector());
//
// 3. Register in DbContext:
//
//    public DbSet<{{pascalCase FEATURE_NAME}}> {{pascalCase FEATURE_NAME}}s => Set<{{pascalCase FEATURE_NAME}}>();
//
//    protected override void OnModelCreating(ModelBuilder modelBuilder)
//    {
//        modelBuilder.HasPostgresExtension("vector");
//        modelBuilder.ApplyConfiguration(new {{pascalCase FEATURE_NAME}}Configuration());
//    }
//
// 4. Create and apply migration:
//
//    dotnet ef migrations add Add{{pascalCase FEATURE_NAME}}WithVector -p src/{{NAMESPACE}}.Infrastructure -s src/{{NAMESPACE}}.Web
//    dotnet ef database update -p src/{{NAMESPACE}}.Infrastructure -s src/{{NAMESPACE}}.Web
//
// ============================================================