/* 
 *                                dbMango
 *
 * Copyright 2025 Deutsche Bank AG
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
namespace Rms.Risk.Mango.Language.Ast;

public class AstStageUnwind : AstStage  
{
    public AstStageUnwind() {}
    public AstStageUnwind(string fieldName, string? indexName = null)
    {
        Name = fieldName;
        Index = indexName!;
    }

    public string Name { get; internal set { field = PreprocessFieldName(value); }} = "";
    public string? Index { get; internal set { field = PreprocessFieldName(value); }}

    public override void Append(StringBuilder sb, int indent)
    {
        if (string.IsNullOrWhiteSpace(Index))
            sb.AppendLine($"{Spaces(indent)}UNWIND {Name}");
        else
            sb.AppendLine($"{Spaces(indent)}UNWIND {Name} INDEX {Index}");
    }

    public override JsonNode? AsJson()
    {
        if ( string.IsNullOrWhiteSpace(Index) )
        {
            var res = new JsonObject
            {{ 
                    "$unwind", 
                    new JsonObject
                    {
                        { "path", JsonValue.Create($"${Name}") }
                    }
            }};
            return ApplyOptions(res);
        }
        else
        {
            var res = new JsonObject
            {{ 
                    "$unwind", 
                    new JsonObject
                    {
                        { "path", JsonValue.Create($"${Name}") },
                        { "includeArrayIndex", JsonValue.Create(Index) }
                    }
            }};
            return ApplyOptions(res);
        }
    }
}
