using GB5Shared.DTO.Framework.Login;
using GB5Shared.Telemetry;
using Newtonsoft.Json;
using SkillManagementBLL.EmployeeSkillProfile;
using SkillManagementDAL.CustomCode.EmployeeSkillProfile;
using SkillManagementDAL.DTO.EmployeeSkillProfile;

namespace SkillManagementBLL.SkillGrant
{
    public class SkillGrantBLL : ISkillGrantBLL
    {
        private readonly IEmployeeSkillProfileDAL _EmployeeSkillProfileDAL;
        private readonly IEmployeeSkillProfileBLL _EmployeeSkillProfileBLL;

        public SkillGrantBLL(IEmployeeSkillProfileDAL employeeSkillProfileDAL, IEmployeeSkillProfileBLL employeeSkillProfileBLL)
        {
            _EmployeeSkillProfileDAL = employeeSkillProfileDAL;
            _EmployeeSkillProfileBLL = employeeSkillProfileBLL;
        }

        public async Task ApplySkillGrantAsync(int employeeId, int skillId, int productFamilyId, int modelId, byte levelNo, LoginDTO loginDTO, CancellationToken ct)
        {
            GB5Trace.Step("apply-skill-grant", new { employeeId, skillId, productFamilyId, modelId, levelNo });

            var existingJson = await _EmployeeSkillProfileDAL.GetByEmployee(employeeId, 0, skillId, loginDTO, ct).ConfigureAwait(false);
            var existing = JsonConvert.DeserializeObject<List<EmployeeSkillProfileDTO>>(existingJson) ?? new List<EmployeeSkillProfileDTO>();

            var match = existing.FirstOrDefault(p => p.ProductFamilyId == productFamilyId && p.ModelId == modelId);

            // Never auto-downgrade an existing higher level.
            if (match != null && match.CurrentLevNo >= levelNo)
            {
                GB5Trace.Step("skill-grant-no-op-not-higher", new { employeeId, skillId, existingLevel = match.CurrentLevNo, grantedLevel = levelNo });
                return;
            }

            var dto = match ?? new EmployeeSkillProfileDTO
            {
                EmployeeId = employeeId,
                SkillId = skillId,
                ProductFamilyId = productFamilyId,
                ModelId = modelId,
                CreatedById = loginDTO.UserId,
                CreatedOn = DateTime.UtcNow,
                Status = 1,
                SourceType = 5,
                SortOrder = 9999
            };

            dto.CurrentLevNo = levelNo;
            dto.ProfileStatus = 1; // Current
            dto.AssessedDt = DateTime.UtcNow;
            dto.AssessedById = -1; // system/auto — granted via training completion, not a human assessor

            await _EmployeeSkillProfileBLL.Save(dto, loginDTO, ct).ConfigureAwait(false);
        }
    }
}