using System.ComponentModel.DataAnnotations;
using AdminDAL.CustomCode.FormTemplate;
using AdminDAL.CustomCode.TemplateData;
using AdminDAL.DTO.TemplateData;
using GB5Shared.DTO.Framework.Login;
using GB5Shared.EventLogPublish;
using GB5Shared.Resource.Response;
using GB5Shared.Telemetry;
using GB5Shared.Validation;
using Microsoft.Extensions.Logging;
using static GB5Shared.GB5Constant.Constant;

namespace AdminBLL.TemplateData
{
    // GB5-native rebuild of the legacy GB4 AdminBLL.TemplateData. The legacy source
    // (~/Downloads/GB4Solution/BLL/AdminBLL/TemplateData/TemplateDataBLL.cs) is reference-only —
    // see /Users/venkatv/.claude/plans/we-have-done-a-adaptive-stroustrup.md.
    public class TemplateDataBLL : ITemplateDataBLL
    {
        private readonly ITemplateDataDAL _DAL;
        private readonly IFormTemplateDAL _FormTemplateDAL;
        private readonly IValidation _Validation;
        private readonly EventLogPublish _EventLog;
        private readonly ILogger<TemplateDataBLL> _Logger;

        public TemplateDataBLL(
            ITemplateDataDAL DAL, IFormTemplateDAL FormTemplateDAL, IValidation Validation,
            EventLogPublish EventLog, ILogger<TemplateDataBLL> Logger)
        {
            _DAL = DAL;
            _FormTemplateDAL = FormTemplateDAL;
            _Validation = Validation;
            _EventLog = EventLog;
            _Logger = Logger;
        }

        public async Task<string> GetTemplateData(int TemplateDataId, LoginDTO LoginDTO, CancellationToken ct)
        {
            GB5Trace.Step("get-templatedata", new { TemplateDataId });
            return await _DAL.GetTemplateData(TemplateDataId, LoginDTO, ct).ConfigureAwait(false);
        }

        public async Task<string> GetSelectListTemplateData(int FormTemplateId, LoginDTO LoginDTO, CancellationToken ct)
            => await _DAL.GetSelectListTemplateData(FormTemplateId, LoginDTO, ct).ConfigureAwait(false);

        public async Task<string> SaveTemplateData(TemplateDataDTO TemplateDataDTO, LoginDTO LoginDTO, CancellationToken ct)
        {
            ArgumentNullException.ThrowIfNull(TemplateDataDTO);
            var isNew = TemplateDataDTO.TemplateDataId <= 0;

            GB5Trace.Step("validate-templatedata", new { TemplateDataDTO.FormTemplateId });
            try
            {
                await _Validation.Range(1, int.MaxValue, TemplateDataDTO.FormTemplateId, nameof(TemplateDataDTO.FormTemplateId)).ConfigureAwait(false);

                var formTemplate = await _FormTemplateDAL.GetFormTemplateByCode(
                    TemplateDataDTO.FormTemplateCode, LoginDTO, ct).ConfigureAwait(false);
                if (formTemplate is null)
                    throw new ValidationException(
                        $"FormTemplateCode '{TemplateDataDTO.FormTemplateCode}' does not reference an existing form.");

                // Resolved server-side from FormTemplateCode, never trusted from the client —
                // the caller only needs to know the form's own code, not its internal id, and a
                // client-submitted FormTemplateId that didn't match the code would either violate
                // the FK constraint or (worse) silently attach this row to the wrong form.
                TemplateDataDTO.FormTemplateId = formTemplate.FormTemplateId;

                TemplateDataDTO.TemplateDataModifiedById = LoginDTO.UserId;
                TemplateDataDTO.TemplateDataModifiedOn = DateTime.UtcNow;
                // Real TENANTID column on TTEMPLATEDATA (FK-constrained) — resolved server-side,
                // never trusted from the client.
                TemplateDataDTO.TenantId = LoginDTO.ClientId;

                GB5Trace.Step("save-templatedata", new { TemplateDataDTO.TemplateDataId, isNew });

                if (isNew)
                {
                    TemplateDataDTO.TemplateDataCreatedById = LoginDTO.UserId;
                    TemplateDataDTO.TemplateDataCreatedOn = DateTime.UtcNow;
                    TemplateDataDTO.TemplateDataStatus = 1;

                    // TEMPLATEDATAID is a real IDENTITY column (confirmed against a live
                    // database) — the DB assigns it, not an AutoNumber allocation.
                    TemplateDataDTO.TemplateDataId = await _DAL.SaveTemplateData(TemplateDataDTO, LoginDTO, ct).ConfigureAwait(false);
                }
                else
                {
                    await _DAL.UpdateTemplateData(TemplateDataDTO, LoginDTO, ct).ConfigureAwait(false);
                }

                // "genericTable" (Dynamic Table) forms also get the submitted values written
                // into D_<FormTemplateCode> — see TemplateDataDAL.PostDataToDynamicTable.
                // TEMPLATEDATADATA (the JSON blob) is populated either way, above.
                if (formTemplate.FormTemplateDataTableType == 1)
                {
                    GB5Trace.Step("post-data-to-dynamic-table", new { formTemplate.FormTemplateCode });
                    await _DAL.PostDataToDynamicTable(TemplateDataDTO, formTemplate, LoginDTO, ct).ConfigureAwait(false);
                }

                GB5Trace.Step("event-publish", new { EventTypeId = EventTypeConstant.SAVETEMPLATEDATAEVENTTYPEID });
                await _EventLog.PublishEventLogAsync(
                    isNew ? "TemplateData Created" : "TemplateData Updated",
                    TemplateDataDTO,
                    isNew ? EventTypeConstant.SAVETEMPLATEDATAEVENTTYPEID : EventTypeConstant.UPDATETEMPLATEDATAEVENTTYPEID,
                    TemplateDataDTO.TemplateDataId, LoginDTO, ct: ct).ConfigureAwait(false);

                return isNew
                    ? $"{SuccessResponse.SaveSuccessMessage} {TemplateDataDTO.TemplateDataId}"
                    : $"{SuccessResponse.UpdateSuccessMessage} {TemplateDataDTO.TemplateDataId}";
            }
            catch (ValidationException vex)
            {
                GB5Trace.MarkFailed("save-templatedata-validation-failed", vex);
                throw new Exception(vex.Message);
            }
            catch (Exception ex)
            {
                GB5Trace.MarkFailed("save-templatedata-failed", ex);
                _Logger.LogError(ex, "SaveTemplateData failed for FormTemplateId {Id}", TemplateDataDTO.FormTemplateId);
                // No AutoNumber rollback needed — TEMPLATEDATAID is a real IDENTITY column.
                throw;
            }
        }

        public async Task<string> DeleteTemplateData(int TemplateDataId, LoginDTO LoginDTO, CancellationToken ct)
        {
            GB5Trace.Step("delete-templatedata", new { TemplateDataId });
            try
            {
                var result = await _DAL.DeleteTemplateData(TemplateDataId, LoginDTO, ct).ConfigureAwait(false);

                GB5Trace.Step("event-publish", new { EventTypeId = EventTypeConstant.DELETETEMPLATEDATAEVENTTYPEID });
                await _EventLog.PublishEventLogAsync(
                    "TemplateData Deleted", new { TemplateDataId }, EventTypeConstant.DELETETEMPLATEDATAEVENTTYPEID,
                    TemplateDataId, LoginDTO, ct: ct).ConfigureAwait(false);

                return result;
            }
            catch (Exception ex)
            {
                GB5Trace.MarkFailed("delete-templatedata-failed", ex);
                _Logger.LogError(ex, "DeleteTemplateData failed for TemplateDataId {Id}", TemplateDataId);
                throw;
            }
        }
    }
}