## Inventory Management System

### Objective
Create a console-based inventory management system for a small store with real-time tracking and alerts.

### Technical Requirements

#### 1. Data Structures
```csharp
class Product {
    public string ProductId { get; set; }  // Format: XXX-999
    public string Name { get; set; }
    public int Quantity { get; set; }
    public decimal Price { get; set; }
    public Category Category { get; set; }
    public DateTime LastRestocked { get; set; }
}

enum Category {
    Electronics,
    Clothing,
    Food,
    Books
}
```

#### 2. Required Functionality

a) **Product Management**
- Add new products with validation:
  - ProductId: Unique, format XXX-999
  - Name: 3-50 characters
  - Quantity: Non-negative
  - Price: Between $0.01 and $10000.00
  - Category: Must be valid enum value
- Update existing products
- Remove products
- Track last restock date

b) **Inventory Operations**
- Stock increase (restock)
- Stock decrease (sales)
- Low stock alerts (< 5 items)
- Out of stock alerts
- Calculate total inventory value
- Track product turnover

c) **Reporting**
- List all products
- Filter by:
  - Category
  - Price range
  - Stock level
- Sort by:
  - Name
  - Quantity
  - Price
  - Last restock date

d) **Alerts System**
- Immediate alerts for:
  - Low stock items
  - Out of stock items
  - High value items (>$1000)
- Daily inventory summary

#### 3. User Interface Requirements
- Main menu with numbered options
- Sub-menus for specific functions
- Clear success/error messages
- Confirmation for critical actions
- Format currency values properly
- Format dates consistently

#### 4. Data Validation
- Prevent duplicate ProductIds
- Validate quantity changes
- Verify price updates
- Check category assignments
- Validate date entries

### Sample Interaction
```
=== Inventory Management System ===
1. View Inventory
2. Add Product
3. Update Stock
4. Generate Reports
5. View Alerts
6. Exit

Enter choice (1-6): 1

Current Inventory:
ID      Name            Qty   Price   Category    Last Restocked
-----------------------------------------------------------
ABC-123 Laptop         10    $899.99  Electronics 10/28/2024
DEF-456 T-Shirt        25    $19.99   Clothing   10/27/2024
GHI-789 Novel          8     $14.99   Books      10/25/2024

Low Stock Alert: Novel (8 units)
Total Inventory Value: $9,499.64

Enter product ID to view details or 'M' for menu:
```

### Evaluation Criteria

#### 1. Code Organization (25%)
- Class structure
- Method organization
- Variable naming
- Code documentation
- Implementation efficiency

#### 2. Data Management (25%)
- Storage implementation
- Update handling
- Search efficiency
- Sort implementation
- Alert system

#### 3. Error Handling (25%)
- Input validation
- Exception management
- Edge cases
- Recovery procedures
- User feedback

#### 4. User Interface (25%)
- Menu clarity
- Information display
- Navigation logic
- Error messages
- Overall usability