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+# PeopleDesk User Guide
+
+Friendly guide for **new users**, **testers**, and **developers**.
+
+PeopleDesk is an Employee Management System for attendance, leave, payroll, performance, and reporting — with role-based access for Admin, HR, and Employee.
+
+---
+
+## 1. Quick start (everyone)
+
+1. Open the app: `http://localhost:5173`
+2. Sign in with a demo account (below)
+3. Use the left menu (it changes by role)
+4. Open **User Guide** inside the app anytime for help
+
+### Demo accounts
+
+| Role | Email | Password | What you can do |
+|------|-------|----------|-----------------|
+| Admin | `admin@ems.com` | `Admin@123` | Everything, including departments |
+| HR | `hr@ems.com` | `Hr@12345` | Employees, leave approvals, payroll, reviews |
+| Employee | `john@ems.com` | `Employee@123` | Own attendance, leave, payslips, profile |
+
+---
+
+## 2. Main flow (simple)
+
+```mermaid
+flowchart LR
+  Login[Login] --> Dashboard[Dashboard]
+  Dashboard --> Attendance[Attendance]
+  Attendance --> Leaves[Leave_Requests]
+  Leaves --> Payroll[Payroll]
+  Payroll --> Reports[Reports_and_Notifications]
+```
+
+---
+
+## 3. Who should use which path?
+
+```mermaid
+flowchart TD
+  Start[Open_PeopleDesk] --> Role{Select_role_by_login}
+  Role -->|Admin| AdminPath[Manage_Depts_Employees_Approvals_Payroll]
+  Role -->|HR| HrPath[Manage_Employees_Approvals_Payroll_Reviews]
+  Role -->|Employee| EmpPath[CheckIn_ApplyLeave_ViewPayslip_Profile]
+```
+
+### Plain-language permissions
+
+| Feature | Admin | HR | Employee |
+|---------|-------|----|----------|
+| Dashboard | Yes | Yes | Yes |
+| Manage employees | Yes | Yes | Own profile only |
+| Manage departments | Yes | View | No |
+| Check in / out | Yes | Yes | Yes |
+| Apply leave | Yes | Yes | Yes |
+| Approve / reject leave | Yes | Yes | No |
+| Generate payroll | Yes | Yes | View/download own |
+| Performance reviews | Create | Create | View own |
+
+---
+
+## 4. New employee guide
+
+1. Login with your email/password  
+2. Go to **Attendance** → **Check in**  
+3. At end of day → **Check out**  
+4. Need time off → **Leaves** → choose type + dates → Apply  
+5. Watch status: Pending → Approved / Rejected  
+6. Open **Payroll** to download salary PDF when ready  
+7. Update phone in **Profile**
+
+### Attendance diagram
+
+```mermaid
+flowchart TD
+  A[Check_In_once_per_day] --> B[Work]
+  B --> C[Check_Out]
+  C --> D[Hours_calculated]
+  D --> E{Hours_over_8}
+  E -->|Yes| F[Overtime_added]
+  E -->|No| G[Normal_hours_only]
+```
+
+**Important:** Only one check-in per employee per day. A second check-in shows an expected error.
+
+---
+
+## 5. Leave flow (HR + Employee)
+
+```mermaid
+flowchart TD
+  Emp[Employee_applies_leave] --> Pending[Status_Pending]
+  Pending --> Review{HR_or_Admin_decision}
+  Review -->|Approve| Approved[Status_Approved]
+  Approved --> BalanceDown[Leave_balance_decreases]
+  BalanceDown --> NotifyA[Employee_notification]
+  Review -->|Reject| Rejected[Status_Rejected]
+  Rejected --> NotifyR[Employee_notification]
+  Pending --> Cancel[Employee_can_cancel]
+```
+
+Leave types: Casual, Sick, Paid, Unpaid.
+
+---
+
+## 6. Payroll flow
+
+```mermaid
+flowchart TD
+  Hr[HR_or_Admin_opens_Payroll] --> Fill[Select_employee_month_year]
+  Fill --> Calc[System_calculates_net_salary]
+  Calc --> Save[Payroll_saved]
+  Save --> Pdf[Download_PDF_payslip]
+  Save --> Note[Employee_gets_notification]
+```
+
+Formula:
+
+`Net = Basic + Allowances + Bonuses - Deductions - Tax`
+
+**Currency:** All money values (salary, budget, payroll, payslips) use **Indian Rupees (INR)** with Indian grouping — e.g. `₹75,000.00` in the UI and `Rs. 75,000.00` on PDF payslips.
+
+---
+
+## 7. Tester checklist
+
+- [ ] Login works for Admin, HR, Employee  
+- [ ] Employee cannot manage all employees/departments  
+- [ ] Duplicate attendance check-in is blocked  
+- [ ] Leave approve reduces balance; reject does not  
+- [ ] Payroll PDF downloads  
+- [ ] Notifications appear after leave review and payroll generate  
+- [ ] Mobile/responsive layout remains usable under 768px  
+
+---
+
+## 8. Developer guide
+
+### Run locally
+
+```bash
+# Backend
+cd people-desk-be
+npm install
+npm run seed
+npm run dev
+
+# Frontend (new terminal)
+cd people-desk-fe
+npm install
+npm run dev
+```
+
+- UI: `http://localhost:5173`
+- API: `http://localhost:5000`
+- Root `.env` needs `MONGODB_URI`, `JWT_SECRET`, `PORT`, `CLIENT_URL`
+
+### Access My Database (MongoDB Atlas)
+
+PeopleDesk stores data in **MongoDB Atlas** (cloud). Local connection string lives in root `.env` as `MONGODB_URI` (also mirrored in `atlas-credentials.env` — keep both private).
+
+1. Open [MongoDB Atlas](https://cloud.mongodb.com/) and sign in  
+2. Choose your project → click the cluster (e.g. `Cluster0`)  
+3. Click **Browse Collections** to open **Collections** (this is “My Database” in Atlas)  
+4. Select database **`ems`** — you will see collections such as `users`, `employees`, `departments`, `attendances`, `leaverequests`, `payrolls`, `notifications`, etc.  
+5. Optional — connect from a GUI:  
+   - In Atlas: **Connect** → **Drivers** or **MongoDB Compass**  
+   - Copy the URI (same style as `MONGODB_URI` in `.env`)  
+   - Open [MongoDB Compass](https://www.mongodb.com/products/compass) → paste URI → Connect → open database **`ems`**
+
+**Tip:** After `npm run seed` in `people-desk-be`, demo users and sample employees appear under `ems`. If the app cannot connect, check Atlas **Network Access** (your IP allowlist) and that `MONGODB_URI` is correct.
+
+### Architecture
+
+```mermaid
+flowchart TD
+  FE[people-desk-fe_React] -->|JWT_Bearer_API| BE[people-desk-be_Express]
+  BE --> MW[Auth_and_RBAC_middleware]
+  MW --> CTRL[Controllers]
+  CTRL --> DB[(MongoDB_Atlas)]
+```
+
+### Useful API routes
+
+- `POST /api/auth/login`
+- `GET /api/auth/me`
+- `CRUD /api/employees`
+- `CRUD /api/departments`
+- `POST /api/attendance/check-in` · `POST /api/attendance/check-out`
+- `POST /api/leaves` · `PUT /api/leaves/:id/review`
+- `POST /api/payroll/generate` · `GET /api/payroll/:id/payslip`
+- `GET /api/dashboard/stats`
+- `GET /api/notifications`
+
+Use header: `Authorization: Bearer <token>`
+
+---
+
+## 9. Friendly tips
+
+- Menus hide features your role cannot use  
+- If a button fails, read the red message — it usually explains the rule (example: already checked in)  
+- For demos, start as Employee for self-service, then switch to HR/Admin for approvals  
+- Keep `.env` and `atlas-credentials.env` private — never commit secrets  
+
+---
+
+## 10. Need more help?
+
+Inside the app, open **User Guide** from the left menu for the same content in a visual layout.