defmodule Arcana.TestRepo.Migrations.AddGraphTables do
  use Ecto.Migration

  def change do
    # Entities table
    create table(:arcana_graph_entities, primary_key: false) do
      add(:id, :binary_id, primary_key: true)
      add(:name, :string, null: false)
      add(:type, :string, null: false)
      add(:description, :text)
      add(:embedding, :vector, size: 384)
      add(:metadata, :map, default: %{})

      add(:chunk_id, references(:arcana_chunks, type: :binary_id, on_delete: :nilify_all))

      add(
        :collection_id,
        references(:arcana_collections, type: :binary_id, on_delete: :delete_all)
      )

      timestamps()
    end

    create(index(:arcana_graph_entities, [:chunk_id]))
    create(index(:arcana_graph_entities, [:collection_id]))
    create(index(:arcana_graph_entities, [:type]))
    create(unique_index(:arcana_graph_entities, [:name, :collection_id]))

    # Relationships table
    create table(:arcana_graph_relationships, primary_key: false) do
      add(:id, :binary_id, primary_key: true)
      add(:type, :string, null: false)
      add(:description, :text)
      add(:strength, :integer)
      add(:metadata, :map, default: %{})

      add(
        :source_id,
        references(:arcana_graph_entities, type: :binary_id, on_delete: :delete_all),
        null: false
      )

      add(
        :target_id,
        references(:arcana_graph_entities, type: :binary_id, on_delete: :delete_all),
        null: false
      )

      timestamps()
    end

    create(index(:arcana_graph_relationships, [:source_id]))
    create(index(:arcana_graph_relationships, [:target_id]))
    create(index(:arcana_graph_relationships, [:type]))

    # Entity mentions table (tracks where entities appear in chunks)
    create table(:arcana_graph_entity_mentions, primary_key: false) do
      add(:id, :binary_id, primary_key: true)
      add(:span_start, :integer)
      add(:span_end, :integer)
      add(:context, :text)

      add(
        :entity_id,
        references(:arcana_graph_entities, type: :binary_id, on_delete: :delete_all),
        null: false
      )

      add(
        :chunk_id,
        references(:arcana_chunks, type: :binary_id, on_delete: :delete_all),
        null: false
      )

      timestamps()
    end

    create(index(:arcana_graph_entity_mentions, [:entity_id]))
    create(index(:arcana_graph_entity_mentions, [:chunk_id]))

    # Communities table (hierarchical clusters of entities)
    create table(:arcana_graph_communities, primary_key: false) do
      add(:id, :binary_id, primary_key: true)
      add(:level, :integer, null: false, default: 0)
      add(:description, :text)
      add(:summary, :text)
      add(:entity_ids, {:array, :binary_id}, default: [])
      add(:dirty, :boolean, default: true)
      add(:change_count, :integer, default: 0)

      add(
        :collection_id,
        references(:arcana_collections, type: :binary_id, on_delete: :delete_all)
      )

      timestamps()
    end

    create(index(:arcana_graph_communities, [:collection_id]))
    create(index(:arcana_graph_communities, [:level]))
    create(index(:arcana_graph_communities, [:dirty]))
  end
end