using Microsoft.Data.SqlClient;

namespace Library;

public class CategoryTreeData
{
	private readonly List<CategoryItemData> m_RootElements = new( );
	public List<CategoryItemData> RootElements { get => m_RootElements; }

	private readonly Dictionary<int,CategoryItemData> m_AllElements = new( );

	public int GetRootID( )
	{
		if ( m_RootElements.Count == 0 )
			return 0;
		return m_RootElements[0].ID;
	}

	public CategoryItemData? FindCategory( int id )
	{
		if ( m_AllElements.TryGetValue( id , out CategoryItemData? value ) )
			return value;
		return null;
	}

	public void LoadCategoryTree( SqlConnection connection )
	{
		using SqlDataReader reader = new SQLBuilder( connection , "select id,idfat,label,ime_x,cnt,lis_txt from [select_razdeli]" )
			.ExecuteReader( );

		while ( reader.Read( ) )
		{
			CategoryItemData model = new( )
			{
				ID = reader.Int( "id" ) ,
				ParentID = reader.Int( "idfat" ) ,
				ElementCount = reader.Int( "cnt" ) ,
				Depth = reader.Int( "label" ) ,
				Name = reader.StringSafe( "ime_x" ).Trim( ),
				Catego_opis = reader.StringSafe( "lis_txt" ).Trim( )
			};
			m_AllElements[model.ID] = model;
		}

		foreach ( CategoryItemData m in m_AllElements.Values )
		{
			if ( m_AllElements.TryGetValue( m.ParentID , out CategoryItemData? parent ) )
				parent.Children.Add( m );
			else
				m_RootElements.Add( m );
		}
	}

}