using System.Text;

namespace Connected.Data.Schema.Sql
{
	internal class ColumnAdd : ColumnTransaction
	{
		public ColumnAdd(ISchemaColumn column) : base(column)
		{
		}

		protected override async Task OnExecute()
		{
			await Context.Execute(CommandText);

			if (Column.IsPrimaryKey)
				await new PrimaryKeyAdd(Column).Execute(Context);

			if (!string.IsNullOrWhiteSpace(Column.DefaultValue))
				await new DefaultAdd(Column, Context.Schema.Name).Execute(Context);
		}

		private string CommandText
		{
			get
			{
				var text = new StringBuilder();

				text.AppendLine($"ALTER TABLE {Escape(Context.Schema.SchemaName(), Context.Schema.Name)}");
				text.AppendLine($"ADD COLUMN {CreateColumnCommandText(Column)}");

				return text.ToString();
			}
		}
	}
}