Connected.Framework/Connected.Data/Update/DeleteCommandBuilder.cs

using Connected.Entities.Annotations;
using Connected.Entities.Storage;
using System.Collections.Concurrent;
using System.Reflection;

namespace Connected.Data.Update;

internal class DeleteCommandBuilder : CommandBuilder
{
    private static readonly ConcurrentDictionary<string, StorageOperation> _cache;

    static DeleteCommandBuilder()
    {
        _cache = new();
    }

    private static ConcurrentDictionary<string, StorageOperation> Cache => _cache;

    protected override StorageOperation OnBuild()
    {
        WriteLine($"DELETE [{Schema.Schema}].[{Schema.Name}] (");
        WriteWhere();

        var result = new StorageOperation { CommandText = CommandText };

        foreach (var parameter in Parameters)
            result.AddParameter(parameter);

        Cache.TryAdd(Entity.GetType().FullName, result);

        return result;
    }

    private void WriteWhere()
    {
        Write("WHERE ");

        foreach (var property in Properties)
        {
            if (property.GetCustomAttribute<PrimaryKeyAttribute>() is not null)
            {
                var columnName = ColumnName(property);

                CreateParameter(property);

                Write($"{ColumnName} = @{ColumnName}");
            }
        }

        Write(";");
    }

    protected override bool TryGetExisting(out StorageOperation? result)
    {
        return Cache.TryGetValue(Entity.GetType().FullName, out result);
    }
}