using System.Data;
using GB5Shared.DTO.Ice;
using GB5Shared.DTO.Framework.Login;
using IceImportDAL.DTO.IceImportPipeline;

namespace IceImportBLL.FieldResolvers;

// One resolved value + optional warning finding (never a silent default — see SourceValueResolver).
public class FieldResolutionResult
{
    public object? Value { get; set; }
    public IceImportFieldErrorDTO? Warning { get; set; }

    public static FieldResolutionResult Ok(object? value) => new() { Value = value };

    public static FieldResolutionResult WithWarning(object? value, IceImportFieldErrorDTO warning)
        => new() { Value = value, Warning = warning };
}

// Everything a single-field resolver needs: the IceMapDetails config row driving this field, the
// current source DataRow, the caller's LoginDTO, the pre-resolved Code/Name -> Id lookup tables
// (populated once up front by IEntityLookupService — no per-row I/O), and hierarchy context for
// parent/grandparent id resolvers.
public class FieldResolutionContext
{
    public required IceMapDetailsDTO DetailConfig { get; init; }
    public required DataRow SourceRow { get; init; }
    public required LoginDTO Login { get; init; }
    public required int RowNumber { get; init; }

    // Keyed by IceMapDetails.EntityId (the entity being looked up), then by the raw code/name
    // value from the source file -> resolved target Id.
    public IReadOnlyDictionary<int, Dictionary<string, int>> Lookups { get; init; }
        = new Dictionary<int, Dictionary<string, int>>();

    // ValueType=6 (ParentIdAssignmentResolver): the immediate parent row's correlation/real id.
    public int? ParentId { get; init; }

    // ValueType=8 (FirstParentValueResolver): the grandparent row's id, for 3-level hierarchies.
    public int? FirstParentId { get; init; }

    // Threaded through so ValueType=9/10 (Fixed/Global "during update") resolvers know whether
    // this row is being inserted or updated.
    public bool IsUpdateMode { get; init; }
}

// One implementation per legacy IceMapDetailsValueType. DI-scanned as
// IEnumerable<IIceFieldValueResolver>; the pipeline selects by ValueType, modeled on
// GB5Shared.GB5Library.Qualifier.IQualifierExecutor's Key-based dispatch style.
public interface IIceFieldValueResolver
{
    int ValueType { get; }

    Task<FieldResolutionResult> ResolveAsync(FieldResolutionContext ctx, CancellationToken ct);
}