Controller + metrics

backend/pom.xml

@@ -34,7 +34,6 @@
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-starter-web</artifactId>
 		</dependency>
-
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
 			<artifactId>spring-boot-devtools</artifactId>
@@ -46,6 +45,15 @@
 			<artifactId>spring-boot-starter-test</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-validation</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<optional>true</optional>
+		</dependency>
 	</dependencies>
 
 	<build>

backend/src/main/java/com/inventory/backend/controller/ProductController.java

@@ -0,0 +1,90 @@
+package com.inventory.backend.controller;
+
+import com.inventory.backend.dto.ProductDTO;
+import com.inventory.backend.dto.ProductPage;
+import com.inventory.backend.model.InventoryMetrics;
+import com.inventory.backend.model.Product;
+import com.inventory.backend.service.ProductService;
+import jakarta.validation.Valid;
+import org.springframework.web.bind.annotation.*;
+
+import java.util.*;
+
+@RestController
+@RequestMapping("/products")
+@CrossOrigin(origins = "http://localhost:8080")
+public class ProductController {
+    private final ProductService service;
+
+    public ProductController(ProductService service) {
+        this.service = service;
+    }
+
+    // GET /products
+    @GetMapping
+    public ProductPage getProducts(
+            @RequestParam Optional<String> name,
+            @RequestParam Optional<List<String>> category,
+            @RequestParam Optional<Boolean> availability,
+            @RequestParam Optional<String> sortBy,
+            @RequestParam Optional<String> sortBy2,
+            @RequestParam(defaultValue = "true") boolean asc,
+            @RequestParam(defaultValue = "true") boolean asc2,
+            @RequestParam(defaultValue = "0") int page,
+            @RequestParam(defaultValue = "10") int size
+    ){
+        Set<String> categorySet = category.map(HashSet::new).orElse(null);
+        return service.getFilteredProductsPage(
+                name,
+                Optional.ofNullable(categorySet),
+                availability,
+                sortBy,
+                sortBy2,
+                asc,
+                asc2,
+                page,
+                size
+        );
+    }
+
+    // POST /products
+    @PostMapping
+    public Product createProduct(@RequestBody @Valid ProductDTO dto) {
+        return service.createProduct(dto);
+    }
+
+    // PUT /products/{id}
+    @PutMapping("/{id}")
+    public Product updateProduct(@PathVariable UUID id, @RequestBody @Valid ProductDTO dto) {
+        return service.updateProduct(id,dto);
+    }
+
+    // DELETE /products/{id}
+    @DeleteMapping("/{id}")
+    public void deleteProduct(@PathVariable UUID id) {
+        service.deleteProduct(id);
+    }
+
+    // POST /products/{id}/outofstock
+    @PostMapping("/{id}/outofstock")
+    public void markOutOfStock(@PathVariable UUID id) {
+        service.markOutOfStock(id);
+    }
+
+    // PUT /products/{id}/instock?defaultQuantity=10
+    @PutMapping("/{id}/instock")
+    public void markInStock(@PathVariable UUID id, @RequestParam(defaultValue = "10") int defaultQuantity) {
+        service.markInStock(id, defaultQuantity);
+    }
+
+    // GET /products/metrics
+    @GetMapping("/metrics")
+    public InventoryMetrics getMetrics() {
+        return service.getMetrics();
+    }
+
+    @GetMapping("/categories")
+    public Set<String> getCategories(){
+        return service.getAllCategories();
+    }
+}

backend/src/main/java/com/inventory/backend/dto/ProductDTO.java

@@ -0,0 +1,62 @@
+package com.inventory.backend.dto;
+
+import jakarta.validation.constraints.*;
+import java.time.LocalDate;
+
+public class ProductDTO {
+    @NotBlank(message = "Name is required")
+    @Size(max = 120, message = "Name must not exceed 120 characters")
+    private String name;
+
+    @NotBlank(message = "Category is required")
+    private String category;
+
+    @NotNull(message = "Unit price is required")
+    @PositiveOrZero(message = "Unit price must be 0 or more")
+    private Double unitPrice;
+
+    @PositiveOrZero(message = "Stock must be 0 or more")
+    private Integer quantityInStock;
+
+    private LocalDate expirationDate;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getCategory() {
+        return category;
+    }
+
+    public void setCategory(String category) {
+        this.category = category;
+    }
+
+    public Double getUnitPrice() {
+        return unitPrice;
+    }
+
+    public void setUnitPrice(Double unitPrice) {
+        this.unitPrice = unitPrice;
+    }
+
+    public Integer getQuantityInStock() {
+        return quantityInStock;
+    }
+
+    public void setQuantityInStock(Integer quantityInStock) {
+        this.quantityInStock = quantityInStock;
+    }
+
+    public LocalDate getExpirationDate() {
+        return expirationDate;
+    }
+
+    public void setExpirationDate(LocalDate expirationDate) {
+        this.expirationDate = expirationDate;
+    }
+}

backend/src/main/java/com/inventory/backend/dto/ProductPage.java

@@ -0,0 +1,30 @@
+package com.inventory.backend.dto;
+
+import com.inventory.backend.model.Product;
+import java.util.List;
+
+public class ProductPage {
+    private List<Product> items;
+    private long total;
+
+    public ProductPage(List<Product> items, long total) {
+        this.items = items;
+        this.total = total;
+    }
+
+    public List<Product> getItems(){
+        return items;
+    }
+
+    public void setItems(List<Product> items) {
+        this.items = items;
+    }
+
+    public long getTotal() {
+        return total;
+    }
+
+    public void setTotal(long total) {
+        this.total = total;
+    }
+}

backend/src/main/java/com/inventory/backend/model/InventoryMetrics.java

@@ -0,0 +1,124 @@
+package com.inventory.backend.model;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+public class InventoryMetrics {
+    private int totalInStock;
+    private double totalValue;
+    private double averagePrice;
+
+    private  Map<String, CategoryMetrics> byCategory;
+
+    public InventoryMetrics() {}
+
+    public InventoryMetrics(int totalInStock, double totalValue, double averagePrice, Map<String, CategoryMetrics> byCategory) {
+        this.totalInStock = totalInStock;
+        this.totalValue = totalValue;
+        this.averagePrice = averagePrice;
+        this.byCategory = byCategory;
+    }
+
+    public static InventoryMetrics fromProductList(List<Product> products) {
+        int totalStock = products.stream().mapToInt(Product::getQuantityInStock).sum();
+
+        double totalValue = products.stream()
+                .mapToDouble(Product::getTotalValue)
+                .sum();
+
+        List<Product> inStock = products.stream()
+                .filter(p -> p.getQuantityInStock() > 0)
+                .collect(Collectors.toList());
+
+        double averagePrice = inStock.isEmpty() ? 0:
+                inStock.stream().mapToDouble(Product::getUnitPrice).average().orElse(0);
+
+        Map<String, CategoryMetrics> categoryMetrics = products.stream()
+                .collect(Collectors.groupingBy(
+                        Product::getCategory,
+                        Collectors.collectingAndThen(Collectors.toList(), CategoryMetrics::fromProductList)
+                ));
+        return new InventoryMetrics(totalStock, totalValue, averagePrice, categoryMetrics);
+    }
+
+    public int getTotalInStock() {
+        return totalInStock;
+    }
+
+    public void setTotalInStock(int totalInStock) {
+        this.totalInStock = totalInStock;
+    }
+
+    public double getTotalValue() {
+        return totalValue;
+    }
+
+    public void setTotalValue(double totalValue) {
+        this.totalValue = totalValue;
+    }
+
+    public double getAveragePrice() {
+        return averagePrice;
+    }
+
+    public void setAveragePrice(double averagePrice) {
+        this.averagePrice = averagePrice;
+    }
+
+    public Map<String, CategoryMetrics> getByCategory() {
+        return byCategory;
+    }
+
+    public void setByCategory(Map<String, CategoryMetrics> byCategory) {
+        this.byCategory = byCategory;
+    }
+
+    public static class CategoryMetrics {
+        private  int inStock;
+        private double totalValue;
+        private double averagePrice;
+
+        public static CategoryMetrics fromProductList(List<Product> products) {
+            int stock = products.stream().mapToInt(Product::getQuantityInStock).sum();
+            double value = products.stream().mapToDouble(Product::getTotalValue).sum();
+
+            List<Product> inStock = products.stream().filter(p -> p.getQuantityInStock() > 0).toList();
+            double avg = inStock.isEmpty() ? 0 :
+                    inStock.stream().mapToDouble(Product::getUnitPrice).average().orElse(0);
+
+            return new CategoryMetrics(stock, value, avg);
+        }
+
+        public CategoryMetrics() {}
+
+        public CategoryMetrics(int inStock, double totalValue, double averagePrice) {
+            this.inStock = inStock;
+            this.totalValue = totalValue;
+            this.averagePrice = averagePrice;
+        }
+
+        public double getTotalValue() {
+            return totalValue;
+        }
+
+        public void setTotalValue(double totalValue) {
+            this.totalValue = totalValue;
+        }
+
+        public double getAveragePrice() {
+            return averagePrice;
+        }
+
+        public void setAveragePrice(double averagePrice) {
+            this.averagePrice = averagePrice;
+        }
+
+        public int getInStock() {
+            return inStock;
+        }
+
+        public void setInStock(int inStock) {
+            this.inStock = inStock;
+        }
+    }
+}