using System.Collections.Immutable;
using Connected.Entities;
using Connected.Entities.Storage;

namespace Connected.Data.Update;

internal class AggregatedCommandBuilder<TEntity>
{
	public StorageOperation? Build(TEntity entity)
	{
		if (entity is not IEntity ie)
			throw new ArgumentException(nameof(entity));

		switch (ie.State)
		{
			case State.New:
				return BuildInsert(ie);
			case State.Default:
				return BuildUpdate(ie);
			case State.Deleted:
				return BuildDelete(ie);
			default:
				throw new NotSupportedException();
		}
	}

	public List<StorageOperation> Build(ImmutableArray<TEntity> entities)
	{
		var result = new List<StorageOperation>();

		foreach (var entity in entities)
			result.Add(Build(entity));

		return result;
	}

	private StorageOperation? BuildInsert(IEntity entity)
	{
		return new InsertCommandBuilder().Build(entity);
	}

	private StorageOperation? BuildUpdate(IEntity entity)
	{
		return new UpdateCommandBuilder().Build(entity);
	}

	private StorageOperation? BuildDelete(IEntity entity)
	{
		return new DeleteCommandBuilder().Build(entity);
	}
}