using GB5Shared.DTO.Framework.Login;
using SwDAL.DTO.RefDataSource;

namespace SwBLL.RefDataSource;

public interface IRefDataSourceBLL
{
    Task<RefDataSourceDTO?> GetById(int refDataSourceId, LoginDTO loginDTO, CancellationToken ct);
    Task<IEnumerable<RefDataSourceDTO>> GetByDbModel(int dbModelId, LoginDTO loginDTO, CancellationToken ct);
    Task<string> Save(RefDataSourceDTO dto, LoginDTO loginDTO, CancellationToken ct);

    /// <summary>Soft delete (STATUS=0) — deregisters a table from this DbModel's reference-data
    /// generation without touching any DdlScript/UpgradePackage already generated from it.</summary>
    Task<string> Delete(int refDataSourceId, LoginDTO loginDTO, CancellationToken ct);

    /// <summary>Resolves a registry row's table/filter, generates the seed script via
    /// IReferenceDataScriptGenerator against the given source server+database (resolved
    /// server-side into a real connection string via IDbServerBLL/ITargetDbExecutor — a raw
    /// connection string is never accepted as a parameter), and saves the result as a new, plain
    /// Draft SW.MSWDDLSCRIPT unconditionally — category (SchemaChange/DataMigration/etc.) is a
    /// ChangeRequest-level concept, not a DdlScript one, and isn't decided here. The script is NOT
    /// attached to any package either; that remains a deliberate, separate governance step via
    /// the already-existing IUpgradePackageBLL.AttachDdlScript, same as any hand-authored script.
    /// Prefer RegenerateIfChangedAsync for repeat runs — this method always creates a new script,
    /// even if nothing changed since the last release.</summary>
    Task<int> GenerateAndRegisterAsync(
        int refDataSourceId, int sourceDbServerId, string sourceDatabaseName,
        int branchId, LoginDTO loginDTO, CancellationToken ct);

    /// <summary>Same generation as GenerateAndRegisterAsync, but first checks whether the
    /// content actually changed since the DbModel's current Released chain (tracker §36.4):
    /// generates the script, computes its checksum, walks the chain the same way
    /// IUpgradePackageBLL.GetProvisioningChain already resolves for real onboarding (Released,
    /// not-superseded, Universal-scope packages), and compares against the checksum of whichever
    /// linked script in that chain targets the same table. Identical → skip, no new Draft script,
    /// no needless re-review. Different (or no prior release touches this table yet) → creates
    /// the new Draft script exactly like GenerateAndRegisterAsync.</summary>
    Task<RefDataRegenerationResultDTO> RegenerateIfChangedAsync(
        int refDataSourceId, int sourceDbServerId, string sourceDatabaseName,
        int branchId, LoginDTO loginDTO, CancellationToken ct);
}

public class RefDataRegenerationResultDTO
{
    public bool    Changed        { get; set; }
    public int?    NewDdlScriptId { get; set; }
    public string? PriorChecksum  { get; set; }
    public string  NewChecksum    { get; set; } = string.Empty;
}