BatchQuery.cs

using System.Collections.Generic;
using System.Linq;

namespace Queries.Core.Builders;

/// <summary>
/// Represents many <see cref="IQuery"/>s that will be executed as a whole
/// </summary>
public class BatchQuery : IQuery
{
    private readonly List<IQuery> _statements;

    /// <summary>
    /// Statements that the current instance holds.
    /// </summary>
    public IReadOnlyList<IQuery> Statements
#if NETSTANDARD
        => _statements.ToArray();
#else
        => _statements.AsReadOnly();
#endif

    /// <summary>
    /// Builds a new <see cref="BatchQuery"/> instance.
    /// </summary>
    /// <param name="queries">queries of the batch.</param>
    public BatchQuery(params IQuery[] queries) => _statements = queries.Where(x => x is not null)
                                                                       .ToList();

    /// <summary>
    /// Adds a statement to this instance
    /// </summary>
    /// <param name="query">The query to add</param>
    /// <returns></returns>
    public BatchQuery AddStatement(IQuery query)
    {
        _statements.Add(query);

        return this;
    }

    /// <summary>
    /// Adds multiple statements to the current instance
    /// </summary>
    /// <param name="queries"></param>
    /// <returns>The current instance</returns>
    public BatchQuery AddStatements(IEnumerable<IQuery> queries)
    {
        _statements.AddRange(queries.Where(q => q is not null));

        return this;
    }
}