develop full initial module

Backend/ERPCore/Domain/Entities/AttendanceRecord.cs

@@ -0,0 +1,40 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Per employee/day attendance row (FR-HR-ATT). <see cref="WorkShiftId"/> is
+/// snapshotted from the employee's shift at ingestion time (docs/12-BACKEND-HRM.md
+/// A.3) so a later shift reassignment never retroactively changes historical
+/// Late/OT figures. Model: docs/12-BACKEND-HRM.md Part C.4.
+/// </summary>
+public class AttendanceRecord
+{
+    public int AttendanceRecordId { get; set; }
+    public int? AttendanceUploadBatchId { get; set; }
+    public AttendanceUploadBatch? AttendanceUploadBatch { get; set; }
+    public int EmployeeId { get; set; }
+    public Employee? Employee { get; set; }
+
+    public DateTime AttendanceDate { get; set; }
+    public TimeSpan? CheckIn { get; set; }
+    public TimeSpan? CheckOut { get; set; }
+    public int WorkShiftId { get; set; }
+    public WorkShift? WorkShift { get; set; }
+
+    public int WorkingMinutes { get; set; }
+    public int LateMinutes { get; set; }
+    public int EarlyLeaveMinutes { get; set; }
+    public int OvertimeMinutes { get; set; }
+
+    public AttendanceStatus AttendanceStatus { get; set; }
+    public RowValidationStatus RowValidationStatus { get; set; } = RowValidationStatus.Valid;
+    public int? DuplicateOfAttendanceRecordId { get; set; }
+
+    public string? Notes { get; set; }
+    public bool IsManualOverride { get; set; }
+    public int? EditedBy { get; set; }
+    public DateTime? EditedAt { get; set; }
+
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/AttendanceUploadBatch.cs

@@ -0,0 +1,31 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Attendance upload batch (FR-HR-ATT) — the transactional document driving the
+/// exact status flow Draft→Validated→Confirmed→UsedInPayroll. Scoped to exactly
+/// one payroll period, numbered via <see cref="NumberSequence"/> (docType "ATT").
+/// Model: docs/12-BACKEND-HRM.md Part C.4.
+/// </summary>
+public class AttendanceUploadBatch
+{
+    public int AttendanceUploadBatchId { get; set; }
+    public string DocNo { get; set; } = string.Empty;
+    public DateTime PeriodStart { get; set; }
+    public DateTime PeriodEnd { get; set; }
+    public AttendanceSourceType SourceType { get; set; }
+    public string? OriginalFileName { get; set; }
+
+    public int UploadedBy { get; set; }
+    public DateTime UploadedAt { get; set; }
+    public AttendanceBatchStatus Status { get; set; } = AttendanceBatchStatus.Draft;
+    public int? ConfirmedBy { get; set; }
+    public DateTime? ConfirmedAt { get; set; }
+
+    public int RowCountTotal { get; set; }
+    public int RowCountDuplicate { get; set; }
+    public int RowCountError { get; set; }
+
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/Branch.cs

@@ -0,0 +1,23 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Branch/location master (FR-HR-MD-01) — multi-branch readiness. Referenced
+/// optionally by <see cref="Employee.BranchId"/> and <see cref="PayrollRun.BranchId"/>.
+/// Deactivated, not deleted, when referenced. Model: docs/12-BACKEND-HRM.md Part C.1.
+/// </summary>
+public class Branch
+{
+    public int BranchId { get; set; }
+    public string Code { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
+    public string? Address { get; set; }
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+
+    /// <summary>PostgreSQL xmin-backed optimistic concurrency token (ETag source).</summary>
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/Department.cs

@@ -0,0 +1,26 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Department master (FR-HR-MD-01) — unlimited self-nesting for a real org chart
+/// (unlike the two-level-capped <see cref="Category"/>); cycle prevention is a
+/// service-level check on write, not a DB constraint. Model: docs/12-BACKEND-HRM.md Part C.1.
+/// </summary>
+public class Department
+{
+    public int DepartmentId { get; set; }
+    public string Code { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
+    public int? ParentDepartmentId { get; set; }
+    public Department? ParentDepartment { get; set; }
+    public int? HeadEmployeeId { get; set; }
+    public Employee? HeadEmployee { get; set; }
+    public int? BranchId { get; set; }
+    public Branch? Branch { get; set; }
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/Designation.cs

@@ -0,0 +1,19 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Job title master (FR-HR-MD-01), standalone — not FK'd to Department, since a
+/// title like "Accountant" can exist in multiple departments. Model: docs/12-BACKEND-HRM.md Part C.1.
+/// </summary>
+public class Designation
+{
+    public int DesignationId { get; set; }
+    public string Code { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/Employee.cs

@@ -0,0 +1,76 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Staff record (FR-HR-MD-02) — distinct from <see cref="User"/> (the system login
+/// account): not every employee has a login, and not every login belongs to an
+/// employee. <see cref="UserId"/> is the optional, explicit, human-confirmed link
+/// between the two (docs/12-BACKEND-HRM.md A.5/C.2, Part B.3.2). Never hard-deleted —
+/// separation is recorded via <see cref="Status"/> + <see cref="LastWorkingDate"/>.
+/// <see cref="EmployeeCode"/> is user-entered (not <see cref="NumberSequence"/>-issued):
+/// HR departments keep their own legacy numbering scheme, and NumberSequence's
+/// year-scoping is the wrong shape for an identifier that must never look "reset".
+/// </summary>
+public class Employee
+{
+    public int EmployeeId { get; set; }
+    public string EmployeeCode { get; set; } = string.Empty;
+
+    // Identity
+    public string FullName { get; set; } = string.Empty;
+    public string? Nic { get; set; }
+    public DateTime? DateOfBirth { get; set; }
+    public Gender? Gender { get; set; }
+    public string? Nationality { get; set; }
+    public string? ProfilePhotoPath { get; set; }
+
+    // Contact
+    /// <summary>The field used for the bidirectional Employee&lt;-&gt;User email cross-check.</summary>
+    public string? Email { get; set; }
+    public string? PersonalMobile { get; set; }
+    public string? AddressLine1 { get; set; }
+    public string? AddressLine2 { get; set; }
+    public string? City { get; set; }
+    public string? PostalCode { get; set; }
+    public string? Country { get; set; }
+
+    // Emergency contact
+    public string? EmergencyContactName { get; set; }
+    public string? EmergencyContactRelationship { get; set; }
+    public string? EmergencyContactPhone { get; set; }
+
+    // Employment
+    public DateTime HireDate { get; set; }
+    public DateTime? ConfirmationDate { get; set; }
+    public DateTime? LastWorkingDate { get; set; }
+    public int DepartmentId { get; set; }
+    public Department? Department { get; set; }
+    public int DesignationId { get; set; }
+    public Designation? Designation { get; set; }
+    public int EmploymentTypeId { get; set; }
+    public EmploymentType? EmploymentType { get; set; }
+    public int? BranchId { get; set; }
+    public Branch? Branch { get; set; }
+    public int WorkShiftId { get; set; }
+    public WorkShift? WorkShift { get; set; }
+    public int? ReportingManagerId { get; set; }
+    public Employee? ReportingManager { get; set; }
+
+    // Statutory (Sri Lanka)
+    public string? EpfNumber { get; set; }
+    public string? EtfNumber { get; set; }
+    public string? TaxIdentificationNumber { get; set; }
+
+    /// <summary>Optional login account link (unique — one User backs at most one Employee).</summary>
+    public int? UserId { get; set; }
+    public User? User { get; set; }
+
+    public EmployeeStatus Status { get; set; } = EmployeeStatus.Active;
+
+    public int CreatedBy { get; set; }
+    public DateTime CreatedAt { get; set; }
+    public int? UpdatedBy { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/EmployeeBankDetail.cs

@@ -0,0 +1,28 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Employee bank account (FR-HR-MD-03), one-to-many — a future split-payment
+/// improvement is possible since this isn't a 1:1 scalar set. Exactly one row per
+/// employee is <see cref="IsPrimary"/>; payroll disbursement targets it.
+/// Model: docs/12-BACKEND-HRM.md Part C.2.
+/// </summary>
+public class EmployeeBankDetail
+{
+    public int EmployeeBankDetailId { get; set; }
+    public int EmployeeId { get; set; }
+    public Employee? Employee { get; set; }
+
+    public string BankName { get; set; } = string.Empty;
+    public string BranchName { get; set; } = string.Empty;
+    public string AccountNumber { get; set; } = string.Empty;
+    public string AccountHolderName { get; set; } = string.Empty;
+    public string? SwiftCode { get; set; }
+    public bool IsPrimary { get; set; }
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/EmployeeDocument.cs

@@ -0,0 +1,36 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Uploaded staff document (FR-HR-DOC-02..04) — the user's "Doc". <see cref="StoredFileName"/>/
+/// <see cref="RelativePath"/> are server-generated (never the client's filename), so the
+/// file is only ever reachable through <see cref="Services.Interfaces.IFileStorageService"/>,
+/// never a guessable static path. Archived, not deleted, so the audit trail of what was
+/// once on file is retained. Model: docs/12-BACKEND-HRM.md Part C.3.
+/// </summary>
+public class EmployeeDocument
+{
+    public int EmployeeDocumentId { get; set; }
+    public int EmployeeId { get; set; }
+    public Employee? Employee { get; set; }
+    public int HrDocumentTypeId { get; set; }
+    public HrDocumentType? HrDocumentType { get; set; }
+
+    public string OriginalFileName { get; set; } = string.Empty;
+    public string StoredFileName { get; set; } = string.Empty;
+    public string RelativePath { get; set; } = string.Empty;
+    public string ContentType { get; set; } = string.Empty;
+    public long SizeBytes { get; set; }
+    public DateTime? IssueDate { get; set; }
+    public DateTime? ExpiryDate { get; set; }
+    public string? Notes { get; set; }
+
+    public int UploadedBy { get; set; }
+    public DateTime UploadedAt { get; set; }
+    public int? VerifiedBy { get; set; }
+    public DateTime? VerifiedAt { get; set; }
+
+    public EmployeeDocumentStatus Status { get; set; } = EmployeeDocumentStatus.Active;
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/EmployeeLoan.cs

@@ -0,0 +1,35 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Loan/Advance (FR-HR-PAY-03) — <see cref="LoanKind"/> discriminates, structurally
+/// identical otherwise. <see cref="OutstandingBalance"/> is denormalized (parallel to
+/// <c>StockLayer.QtyRemaining</c>). Numbered via <see cref="NumberSequence"/> (docType "LOAN").
+/// Model: docs/12-BACKEND-HRM.md Part C.6.
+/// </summary>
+public class EmployeeLoan
+{
+    public int EmployeeLoanId { get; set; }
+    public string DocNo { get; set; } = string.Empty;
+    public int EmployeeId { get; set; }
+    public Employee? Employee { get; set; }
+    public LoanKind LoanKind { get; set; }
+
+    public decimal PrincipalAmount { get; set; }
+    public decimal InterestRate { get; set; }
+    public decimal InstallmentAmount { get; set; }
+    public int NumberOfInstallments { get; set; }
+    public int StartYear { get; set; }
+    public int StartMonth { get; set; }
+    public decimal OutstandingBalance { get; set; }
+    public LoanStatus Status { get; set; } = LoanStatus.Active;
+
+    public int ApprovedBy { get; set; }
+    public DateTime ApprovedAt { get; set; }
+    public int CreatedBy { get; set; }
+    public DateTime CreatedAt { get; set; }
+    public uint RowVersion { get; set; }
+
+    public List<LoanInstallment> Installments { get; set; } = new();
+}

Backend/ERPCore/Domain/Entities/EmployeeSalaryStructure.cs

@@ -0,0 +1,30 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Effective-dated salary structure header (FR-HR-PAY-02) — the audit trail a
+/// salary revision needs (docs/12-BACKEND-HRM.md §13): exactly one row with
+/// <see cref="EffectiveTo"/> null (the current one) per employee at a time.
+/// Model: docs/12-BACKEND-HRM.md Part C.6.
+/// </summary>
+public class EmployeeSalaryStructure
+{
+    public int EmployeeSalaryStructureId { get; set; }
+    public int EmployeeId { get; set; }
+    public Employee? Employee { get; set; }
+
+    public DateTime EffectiveFrom { get; set; }
+    public DateTime? EffectiveTo { get; set; }
+    public decimal BasicSalary { get; set; }
+    public string Currency { get; set; } = "LKR";
+    public SalaryStructureStatus Status { get; set; } = SalaryStructureStatus.Active;
+
+    public int ApprovedBy { get; set; }
+    public DateTime ApprovedAt { get; set; }
+    public int CreatedBy { get; set; }
+    public DateTime CreatedAt { get; set; }
+    public uint RowVersion { get; set; }
+
+    public List<EmployeeSalaryStructureLine> Lines { get; set; } = new();
+}

Backend/ERPCore/Domain/Entities/EmployeeSalaryStructureLine.cs

@@ -0,0 +1,12 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>Allowance/other-deduction line on a salary structure. Model: docs/12-BACKEND-HRM.md Part C.6.</summary>
+public class EmployeeSalaryStructureLine
+{
+    public int EmployeeSalaryStructureLineId { get; set; }
+    public int EmployeeSalaryStructureId { get; set; }
+    public EmployeeSalaryStructure? EmployeeSalaryStructure { get; set; }
+    public int SalaryComponentId { get; set; }
+    public SalaryComponent? SalaryComponent { get; set; }
+    public decimal Amount { get; set; }
+}

Backend/ERPCore/Domain/Entities/EmploymentType.cs

@@ -0,0 +1,20 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Labor category master (FR-HR-MD-01) — a master, not an enum, mirroring
+/// <see cref="Brand"/>: employment categories change with company/labor-law
+/// policy without wanting a code deploy. Model: docs/12-BACKEND-HRM.md Part C.1.
+/// </summary>
+public class EmploymentType
+{
+    public int EmploymentTypeId { get; set; }
+    public string Code { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/HrDocumentType.cs

@@ -0,0 +1,24 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Staff document catalog (FR-HR-DOC-01) — the user's "DocType": a category of
+/// document (NIC, contract, certificate...), not the uploaded file itself (see
+/// <see cref="EmployeeDocument"/>, the "Doc"). Deactivated, not deleted, when
+/// referenced. Model: docs/12-BACKEND-HRM.md Part C.3.
+/// </summary>
+public class HrDocumentType
+{
+    public int HrDocumentTypeId { get; set; }
+    public string Code { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
+    public HrDocumentCategory Category { get; set; }
+    public bool RequiredAtOnboarding { get; set; }
+    public bool ExpiryTracked { get; set; }
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/LeaveBalance.cs

@@ -0,0 +1,24 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Per employee/type/year leave entitlement (FR-HR-LV-03). Unique on
+/// (EmployeeId, LeaveTypeId, Year). RemainingDays is a computed projection, not
+/// stored. Model: docs/12-BACKEND-HRM.md Part C.5.
+/// </summary>
+public class LeaveBalance
+{
+    public int LeaveBalanceId { get; set; }
+    public int EmployeeId { get; set; }
+    public Employee? Employee { get; set; }
+    public int LeaveTypeId { get; set; }
+    public LeaveType? LeaveType { get; set; }
+    public int Year { get; set; }
+
+    public decimal EntitledDays { get; set; }
+    public decimal TakenDays { get; set; }
+    public decimal CarriedForwardDays { get; set; }
+    public decimal AdjustmentDays { get; set; }
+
+    public uint RowVersion { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+}

Backend/ERPCore/Domain/Entities/LeaveRequest.cs

@@ -0,0 +1,31 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Leave request (FR-HR-LV-02) — transactional document, numbered via
+/// <see cref="NumberSequence"/> (docType "LV"). Model: docs/12-BACKEND-HRM.md Part C.5.
+/// </summary>
+public class LeaveRequest
+{
+    public int LeaveRequestId { get; set; }
+    public string DocNo { get; set; } = string.Empty;
+    public int EmployeeId { get; set; }
+    public Employee? Employee { get; set; }
+    public int LeaveTypeId { get; set; }
+    public LeaveType? LeaveType { get; set; }
+
+    public DateTime StartDate { get; set; }
+    public DateTime EndDate { get; set; }
+    public decimal DaysCount { get; set; }
+    public string? Reason { get; set; }
+
+    public LeaveRequestStatus Status { get; set; } = LeaveRequestStatus.Draft;
+    public int? ApprovedBy { get; set; }
+    public DateTime? ApprovedAt { get; set; }
+    public string? RejectionReason { get; set; }
+
+    public int CreatedBy { get; set; }
+    public DateTime CreatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/LeaveType.cs

@@ -0,0 +1,23 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>Leave type master (FR-HR-LV-01). Model: docs/12-BACKEND-HRM.md Part C.5.</summary>
+public class LeaveType
+{
+    public int LeaveTypeId { get; set; }
+    public string Code { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
+    public bool IsPaid { get; set; } = true;
+    /// <summary>Feeds Payroll's No-Pay deduction when true (docs/12-BACKEND-HRM.md §6).</summary>
+    public bool CountsAsNoPay { get; set; }
+    public decimal AccrualPerYear { get; set; }
+    public bool CarryForwardAllowed { get; set; }
+    public int? MaxCarryForwardDays { get; set; }
+    public bool RequiresApproval { get; set; } = true;
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/LoanInstallment.cs

@@ -0,0 +1,26 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Loan installment ledger row. <see cref="PayrollRunId"/> is stamped only when the
+/// consuming <see cref="PayrollRun"/> reaches Locked (docs/12-BACKEND-HRM.md A.4).
+/// Model: docs/12-BACKEND-HRM.md Part C.6.
+/// </summary>
+public class LoanInstallment
+{
+    public int LoanInstallmentId { get; set; }
+    public int EmployeeLoanId { get; set; }
+    public EmployeeLoan? EmployeeLoan { get; set; }
+
+    public int InstallmentNumber { get; set; }
+    public int DueYear { get; set; }
+    public int DueMonth { get; set; }
+    public decimal ScheduledAmount { get; set; }
+    public decimal? PaidAmount { get; set; }
+    public int? PayrollRunId { get; set; }
+    public PayrollRun? PayrollRun { get; set; }
+    public LoanInstallmentStatus Status { get; set; } = LoanInstallmentStatus.Pending;
+
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/PayrollLine.cs

@@ -0,0 +1,41 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Per-employee payroll summary row (FR-HR-PAY-05). EpfEmployerAmount/EtfEmployerAmount
+/// are informational/liability only, never subtracted from NetSalary
+/// (docs/12-BACKEND-HRM.md B.4). Model: docs/12-BACKEND-HRM.md Part C.6.
+/// </summary>
+public class PayrollLine
+{
+    public int PayrollLineId { get; set; }
+    public int PayrollRunId { get; set; }
+    public PayrollRun? PayrollRun { get; set; }
+    public int EmployeeId { get; set; }
+    public Employee? Employee { get; set; }
+
+    public decimal BasicSalary { get; set; }
+    public decimal TotalAllowances { get; set; }
+    public decimal OvertimeAmount { get; set; }
+    public decimal GrossSalary { get; set; }
+
+    public decimal LateDeductionAmount { get; set; }
+    public decimal NoPayAmount { get; set; }
+    public decimal LoanDeductionAmount { get; set; }
+    public decimal EpfEmployeeAmount { get; set; }
+    public decimal EpfEmployerAmount { get; set; }
+    public decimal EtfEmployerAmount { get; set; }
+    public decimal TaxAmount { get; set; }
+    public decimal OtherDeductionsAmount { get; set; }
+    public decimal NetSalary { get; set; }
+
+    public int WorkingDays { get; set; }
+    public int PresentDays { get; set; }
+    public int AbsentDays { get; set; }
+    public int LeaveDays { get; set; }
+    public int OtMinutesTotal { get; set; }
+    public int LateMinutesTotal { get; set; }
+
+    public uint RowVersion { get; set; }
+
+    public List<PayrollLineComponent> Components { get; set; } = new();
+}

Backend/ERPCore/Domain/Entities/PayrollLineComponent.cs

@@ -0,0 +1,18 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>The detailed Basic/Transport/Meal/OT/Late/No-Pay/Loan/EPF/ETF/Tax breakdown. Model: docs/12-BACKEND-HRM.md Part C.6.</summary>
+public class PayrollLineComponent
+{
+    public int PayrollLineComponentId { get; set; }
+    public int PayrollLineId { get; set; }
+    public PayrollLine? PayrollLine { get; set; }
+    public PayrollLineComponentCategory ComponentCategory { get; set; }
+    /// <summary>Set only for structure-sourced Allowance/OtherDeduction lines; null for system-computed lines.</summary>
+    public int? SalaryComponentId { get; set; }
+    public SalaryComponent? SalaryComponent { get; set; }
+    public string Label { get; set; } = string.Empty;
+    public decimal Amount { get; set; }
+    public int SortOrder { get; set; }
+}

Backend/ERPCore/Domain/Entities/PayrollRun.cs

@@ -0,0 +1,33 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Payroll run (FR-HR-PAY-05/06) — the transactional document. Numbered via
+/// <see cref="NumberSequence"/> (docType "PAY"). Model: docs/12-BACKEND-HRM.md Part C.6.
+/// </summary>
+public class PayrollRun
+{
+    public int PayrollRunId { get; set; }
+    public string DocNo { get; set; } = string.Empty;
+    public int PeriodYear { get; set; }
+    public int PeriodMonth { get; set; }
+    /// <summary>Null = company-wide run.</summary>
+    public int? BranchId { get; set; }
+    public Branch? Branch { get; set; }
+    public PayrollRunStatus Status { get; set; } = PayrollRunStatus.Draft;
+
+    public int GeneratedBy { get; set; }
+    public DateTime GeneratedAt { get; set; }
+    public int? ApprovedBy { get; set; }
+    public DateTime? ApprovedAt { get; set; }
+    public int? LockedBy { get; set; }
+    public DateTime? LockedAt { get; set; }
+    public int? UnlockedBy { get; set; }
+    public DateTime? UnlockedAt { get; set; }
+    public string? UnlockReason { get; set; }
+
+    public uint RowVersion { get; set; }
+
+    public List<PayrollLine> Lines { get; set; } = new();
+}

Backend/ERPCore/Domain/Entities/PayrollStatutorySetting.cs

@@ -0,0 +1,21 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Effective-dated EPF/ETF rates (FR-HR-PAY-04) — Sri Lanka defaults (EPF 8%
+/// employee / 12% employer, ETF 3% employer-only), configurable since government
+/// rates can change. Model: docs/12-BACKEND-HRM.md Part C.6.
+/// </summary>
+public class PayrollStatutorySetting
+{
+    public int PayrollStatutorySettingId { get; set; }
+    public decimal EpfEmployeeRate { get; set; } = 0.08m;
+    public decimal EpfEmployerRate { get; set; } = 0.12m;
+    public decimal EtfEmployerRate { get; set; } = 0.03m;
+    public decimal OtMultiplierDefault { get; set; } = 1.5m;
+    public DateTime EffectiveFrom { get; set; }
+    public DateTime? EffectiveTo { get; set; }
+
+    public int CreatedBy { get; set; }
+    public DateTime CreatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/Payslip.cs

@@ -0,0 +1,16 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Thin generation/release marker over a <see cref="PayrollLine"/> — ships as an
+/// HTML print view in this phase, per the confirmed decision (no PDF dependency).
+/// Model: docs/12-BACKEND-HRM.md Part C.6.
+/// </summary>
+public class Payslip
+{
+    public int PayslipId { get; set; }
+    public int PayrollLineId { get; set; }
+    public PayrollLine? PayrollLine { get; set; }
+    public DateTime GeneratedAt { get; set; }
+    public DateTime? ReleasedAt { get; set; }
+    public int? ReleasedBy { get; set; }
+}

Backend/ERPCore/Domain/Entities/SalaryComponent.cs

@@ -0,0 +1,19 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>Allowance/ad hoc deduction master (FR-HR-PAY-01). Model: docs/12-BACKEND-HRM.md Part C.6.</summary>
+public class SalaryComponent
+{
+    public int SalaryComponentId { get; set; }
+    public string Code { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
+    public SalaryComponentType ComponentType { get; set; }
+    public bool IsTaxable { get; set; }
+    public bool IsEpfEtfApplicable { get; set; }
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/TaxSlab.cs

@@ -0,0 +1,19 @@
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Configurable APIT-style marginal tax slab (FR-HR-PAY-04) — government slabs
+/// change with the yearly budget, so this is never hardcoded. <see cref="UpperBound"/>
+/// null means "and above". Model: docs/12-BACKEND-HRM.md Part C.6.
+/// </summary>
+public class TaxSlab
+{
+    public int TaxSlabId { get; set; }
+    public DateTime EffectiveFrom { get; set; }
+    public DateTime? EffectiveTo { get; set; }
+    public decimal LowerBound { get; set; }
+    public decimal? UpperBound { get; set; }
+    public decimal Rate { get; set; }
+
+    public DateTime CreatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Entities/User.cs

@@ -23,6 +23,14 @@ public class User
     /// <summary>AuthHex identity (token <c>UserId</c> GUID); null for the seeded system user.</summary>
     public Guid? AuthUserId { get; set; }
 
+    /// <summary>
+    /// Mirrors the AuthHex identity's email (backfilled at create time by
+    /// <c>UsersController.Create</c>, best-effort by JIT provisioning otherwise).
+    /// Used only for the Employee&lt;-&gt;User cross-link soft match (docs/12-BACKEND-HRM.md
+    /// A.5) — never for authentication, which stays AuthHex's responsibility.
+    /// </summary>
+    public string? Email { get; set; }
+
     /// <summary>Local shadow <see cref="Role"/> assignment; null until an admin assigns one.</summary>
     public int? RoleId { get; set; }
     public Role? Role { get; set; }

Backend/ERPCore/Domain/Entities/WorkShift.cs

@@ -0,0 +1,32 @@
+using ERPCore.Domain.Enums;
+
+namespace ERPCore.Domain.Entities;
+
+/// <summary>
+/// Attendance baseline (FR-HR-MD-01) — the shift definition Late/Early/OT figures
+/// are computed against (docs/12-BACKEND-HRM.md A.3, C.1). <see cref="IsOvernight"/>
+/// is explicit rather than inferred from End&lt;Start, since that comparison alone
+/// is ambiguous for a shift that starts and ends the same clock time next day.
+/// </summary>
+public class WorkShift
+{
+    public int WorkShiftId { get; set; }
+    public string Code { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
+    public TimeSpan StartTime { get; set; }
+    public TimeSpan EndTime { get; set; }
+    public bool IsOvernight { get; set; }
+    public int GraceMinutes { get; set; } = 15;
+    public int BreakMinutes { get; set; } = 60;
+    public int StandardWorkingMinutes { get; set; } = 480;
+    public decimal OtMultiplier { get; set; } = 1.5m;
+
+    /// <summary>Bitmask, bit 0 = Monday .. bit 6 = Sunday.</summary>
+    public int WorkingDaysMask { get; set; } = 0b0111111;
+
+    public EntityStatus Status { get; set; } = EntityStatus.Active;
+
+    public DateTime CreatedAt { get; set; }
+    public DateTime? UpdatedAt { get; set; }
+    public uint RowVersion { get; set; }
+}

Backend/ERPCore/Domain/Enums/AttendanceBatchStatus.cs

@@ -0,0 +1,15 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Attendance upload batch lifecycle (FR-HR-ATT, docs/12-BACKEND-HRM.md C.4) —
+/// exactly the flow specified by the business: once <see cref="Confirmed"/> it
+/// becomes payroll's source of truth; once <see cref="UsedInPayroll"/> it is
+/// immutable even to Unlock (a payroll run must be unlocked/regenerated first).
+/// </summary>
+public enum AttendanceBatchStatus
+{
+    Draft,
+    Validated,
+    Confirmed,
+    UsedInPayroll
+}

Backend/ERPCore/Domain/Enums/AttendanceSourceType.cs

@@ -0,0 +1,13 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Origin of an attendance batch (docs/12-BACKEND-HRM.md C.4). <see cref="BiometricDevice"/>
+/// is a reserved future integration seam (docs §B.7) — no device feed exists yet.
+/// </summary>
+public enum AttendanceSourceType
+{
+    Excel,
+    Csv,
+    Manual,
+    BiometricDevice
+}

Backend/ERPCore/Domain/Enums/AttendanceStatus.cs

@@ -0,0 +1,17 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Per-day attendance classification (docs/12-BACKEND-HRM.md C.4). Lateness/OT are
+/// derived facts (LateMinutes/OvertimeMinutes &gt; 0) on an otherwise Present record,
+/// not separate statuses. <see cref="OnLeave"/> is derived from an overlapping
+/// Approved LeaveRequest with no uploaded punch (§6).
+/// </summary>
+public enum AttendanceStatus
+{
+    Present,
+    Absent,
+    HalfDay,
+    OnLeave,
+    Holiday,
+    WeekOff
+}

Backend/ERPCore/Domain/Enums/EmployeeDocumentStatus.cs

@@ -0,0 +1,11 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Uploaded staff document status (docs/12-BACKEND-HRM.md C.3). Never hard-deleted —
+/// archived instead, mirroring the deactivate-not-delete master convention (FR-MD-08).
+/// </summary>
+public enum EmployeeDocumentStatus
+{
+    Active,
+    Archived
+}

Backend/ERPCore/Domain/Enums/EmployeeStatus.cs

@@ -0,0 +1,16 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// Employee lifecycle status (docs/12-BACKEND-HRM.md C.2). An Employee is never
+/// hard-deleted; separation is recorded here instead (with <c>LastWorkingDate</c>
+/// set), matching the deactivate-not-delete convention for masters (FR-MD-08)
+/// taken one step further since the record must be retained for audit/payroll history.
+/// </summary>
+public enum EmployeeStatus
+{
+    Active,
+    Suspended,
+    Resigned,
+    Terminated,
+    Retired
+}

Backend/ERPCore/Domain/Enums/Gender.cs

@@ -0,0 +1,9 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>Employee gender (docs/12-BACKEND-HRM.md C.2). Optional field, stored as a string.</summary>
+public enum Gender
+{
+    Male,
+    Female,
+    Other
+}

Backend/ERPCore/Domain/Enums/HrDocumentCategory.cs

@@ -0,0 +1,12 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>Staff document catalog category (docs/12-BACKEND-HRM.md C.3). Stored as a string.</summary>
+public enum HrDocumentCategory
+{
+    Identity,
+    Educational,
+    Contract,
+    Certification,
+    Statutory,
+    Other
+}

Backend/ERPCore/Domain/Enums/LeaveRequestStatus.cs

@@ -0,0 +1,11 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>Leave request approval lifecycle (FR-HR-LV-02, docs/12-BACKEND-HRM.md C.5).</summary>
+public enum LeaveRequestStatus
+{
+    Draft,
+    Submitted,
+    Approved,
+    Rejected,
+    Cancelled
+}

Backend/ERPCore/Domain/Enums/LoanInstallmentStatus.cs

@@ -0,0 +1,13 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// An installment flips Pending→Deducted only when its PayrollRun reaches Locked
+/// (docs/12-BACKEND-HRM.md A.4) — never at Generate/Draft, so a discarded/regenerated
+/// draft never prematurely consumes it.
+/// </summary>
+public enum LoanInstallmentStatus
+{
+    Pending,
+    Deducted,
+    Skipped
+}

Backend/ERPCore/Domain/Enums/LoanKind.cs

@@ -0,0 +1,8 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>Loan vs Advance discriminator (docs/12-BACKEND-HRM.md C.6) — structurally identical, differ only in intent/labeling.</summary>
+public enum LoanKind
+{
+    Loan,
+    Advance
+}

Backend/ERPCore/Domain/Enums/LoanStatus.cs

@@ -0,0 +1,8 @@
+namespace ERPCore.Domain.Enums;
+
+public enum LoanStatus
+{
+    Active,
+    Closed,
+    Cancelled
+}

Backend/ERPCore/Domain/Enums/PayrollLineComponentCategory.cs

@@ -0,0 +1,12 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// EmployerContribution lines (EPF-employer, ETF) are informational/liability only —
+/// never subtracted from Net Salary (docs/12-BACKEND-HRM.md B.4).
+/// </summary>
+public enum PayrollLineComponentCategory
+{
+    Earning,
+    Deduction,
+    EmployerContribution
+}

Backend/ERPCore/Domain/Enums/PayrollRunStatus.cs

@@ -0,0 +1,15 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// PayrollRun approval workflow (FR-HR-PAY-06, docs/12-BACKEND-HRM.md C.6). Maps the
+/// business's 5-step flow to 3 stored states: Generate→Draft, Review is a human
+/// action (not stored), Approve→Approved, Lock→Locked (the point loan installments
+/// and attendance batches are stamped consumed — see A.4), Generate Payslips is an
+/// action gated on Locked, not a state.
+/// </summary>
+public enum PayrollRunStatus
+{
+    Draft,
+    Approved,
+    Locked
+}

Backend/ERPCore/Domain/Enums/RowValidationStatus.cs

@@ -0,0 +1,12 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>Per-record outcome of the attendance upload validation pipeline (docs/12-BACKEND-HRM.md §B.3.4).</summary>
+public enum RowValidationStatus
+{
+    Valid,
+    DuplicateWithinBatch,
+    DuplicateConfirmed,
+    EmployeeNotFound,
+    InvalidDateTime,
+    Error
+}

Backend/ERPCore/Domain/Enums/SalaryComponentType.cs

@@ -0,0 +1,12 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>
+/// SalaryComponent master category (docs/12-BACKEND-HRM.md C.6) — for Allowances and
+/// ad hoc Other Deductions only. OT/Late/No-Pay/Loan/EPF/ETF/Tax are system-computed,
+/// not user-defined components, to avoid a generic formula engine nobody asked for.
+/// </summary>
+public enum SalaryComponentType
+{
+    Earning,
+    Deduction
+}

Backend/ERPCore/Domain/Enums/SalaryStructureStatus.cs

@@ -0,0 +1,8 @@
+namespace ERPCore.Domain.Enums;
+
+/// <summary>Effective-dated salary structure status (docs/12-BACKEND-HRM.md C.6) — exactly one Active (open-ended) row per employee at a time.</summary>
+public enum SalaryStructureStatus
+{
+    Active,
+    Superseded
+}