using GB5Shared.DTO.Ice;
using IceImportDAL.DTO.IceImportPipeline;

namespace IceImportBLL.HierarchyMapper;

// One resolved row plus the correlation index used to attach it under the right parent.
// CorrelationIndex is the parsed table's "__ROWINDEX__" column value when present (JSON source —
// see JsonSourceFileParser, where several child rows can legitimately share one index, a true
// 1:many grouping), otherwise the row's plain positional index within its own table (Excel/CSV/XML
// — see FlatTableEntitySplitter, whose per-entity tables all share the same row order/count because
// they're column subsets of one physical source table/sheet).
public readonly record struct ResolvedCandidateRow(int CorrelationIndex, MappedEntityRowDTO Row);

// Builds the parent/child MappedEntityRowDTO tree from independently-resolved per-entity row
// lists, and answers "which field on this child entity holds the parent/grandparent id" so
// CommitAsync's persistence-then-inject-then-save-children sequencing knows where to write the
// real DB-assigned id after the parent's own save returns.
public interface IHierarchyMapper
{
    List<MappedEntityRowDTO> BuildHierarchy(
        Dictionary<int, List<ResolvedCandidateRow>> resolvedRowsByEntity,
        IceMapDTO mapDefinition);

    // ValueType = 6 (ParentIdAssignmentResolver) field on the given child entity, if any.
    string? GetParentIdFieldName(IceMapDTO mapDefinition, int childEntityId);

    // ValueType = 8 (FirstParentValueResolver) field on the given child entity, if any.
    string? GetFirstParentIdFieldName(IceMapDTO mapDefinition, int childEntityId);

    // Every DataType=5 (object/List) destination member in this map — e.g. BOMDTO.BOMDetailArray
    // holding List<BOMDETAILDTO> — describing which child entity it embeds and which of that
    // child's own fields groups multiple flat-file rows under one parent record.
    List<ObjectListRelationshipDTO> GetObjectListRelationships(IceMapDTO mapDefinition);
}