feat(coderbyte): Implement pattern analyzer using strategy design pattern

.mvn/jvm.config

@@ -1,4 +1,8 @@
--Xss16m -Xms256m -Xmx1024m -Djava.awt.headless=true
+-Xss16m
+-XX:+EnableDynamicAgentLoading
+-Xms256m
+-Xmx1024m
+-Djava.awt.headless=true
 --add-exports jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED
 --add-exports jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED
 --add-exports jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED

README.md

@@ -35,6 +35,11 @@ PrimeKit Coding Challenges
             <img height="40" width="40" src="https://cdn.simpleicons.org/codility?viewbox=auto" alt="Codility" />
         </a>
     </td>
+    <td style="padding:10px;">
+        <a href="https://coderbyte.com/" title="Visit CoderByte">
+            <img height="40" width="40" src="https://cdn.simpleicons.org/coderbyte?viewbox=auto" alt="CoderByte" />
+        </a>
+    </td>
  </tr>
 </table>
 
@@ -56,6 +61,11 @@ PrimeKit Coding Challenges
 		<img height="40" width="40" src="https://cdn.simpleicons.org/intellijidea?viewbox=auto" alt="IntelliJ IDEA" />
 	  </a>
 	</td>
+    <td style="padding:10px;">
+        <a href="https://www.jetbrains.com" title="JetBrains">
+            <img height="40" width="40" src="https://cdn.simpleicons.org/jetbrains?viewbox=auto" alt="JetBrains" />
+        </a>
+    </td>
 	<td style="padding:10px;">
 	  <a href="https://openjdk.org/" title="OpenJDK">
 		<img height="40" width="40" src="https://cdn.simpleicons.org/openjdk?viewbox=auto" alt="OpenJDK" />

pom.xml

@@ -35,6 +35,7 @@
     <buildtime.output.log>true</buildtime.output.log>
 
     <lombok.version>1.18.32</lombok.version>
+    <mockito.version>5.20.0</mockito.version>
     <junit-jupiter.version>5.10.2</junit-jupiter.version>
     <junit-platform.version>1.10.2</junit-platform.version>
     <commons-lang3.version>3.14.0</commons-lang3.version>
@@ -140,17 +141,23 @@
       <version>${instancio.version}</version>
       <scope>test</scope>
     </dependency>
-      <dependency>
-          <groupId>org.junit.jupiter</groupId>
-          <artifactId>junit-jupiter</artifactId>
-          <scope>test</scope>
-      </dependency>
-      <dependency>
-        <groupId>org.mockito</groupId>
-        <artifactId>mockito-core</artifactId>
-        <version>${mockito.version}</version>
-        <scope>test</scope>
-      </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-core</artifactId>
+      <version>${mockito.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-junit-jupiter</artifactId>
+      <version>${mockito.version}</version>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <build>
@@ -250,6 +257,7 @@
           <testFailureIgnore>true</testFailureIgnore>
           <excludes>
             <exclude>*com.shortthirdman.primekit.common.*</exclude>
+            <exclude>*com.shortthirdman.primekit.core.*</exclude>
           </excludes>
           <properties>
             <configurationParameters>
@@ -280,6 +288,7 @@
           <sourceEncoding>${project.build.sourceEncoding}</sourceEncoding>
           <excludes>
             <exclude>com/shortthirdman/primekit/common/**/*.java</exclude>
+            <exclude>com/shortthirdman/primekit/core/**/*.java</exclude>
           </excludes>
           <outputEncoding>${project.build.sourceEncoding}</outputEncoding>
           <formats>

src/main/java/com/shortthirdman/primekit/coderbyte/PatternAnalyzer.java

@@ -0,0 +1,61 @@
+package com.shortthirdman.primekit.coderbyte;
+
+import com.shortthirdman.primekit.core.domain.ProductCategory;
+import com.shortthirdman.primekit.core.funcinterface.TaxCalculator;
+import com.shortthirdman.primekit.core.strategy.LuxuryTaxCalculation;
+import com.shortthirdman.primekit.core.strategy.PremiumTaxCalculation;
+import com.shortthirdman.primekit.core.strategy.StandardTaxCalculation;
+import com.shortthirdman.primekit.core.strategy.TaxCalculationStrategy;
+import lombok.RequiredArgsConstructor;
+
+import java.util.Objects;
+
+/**
+ * Calculates tax by category and strategy
+ * @since 1.1.1
+ * @author ShortThirdMan
+ */
+public class PatternAnalyzer {
+
+    private static final Boolean DEBUG = System.getenv("DEBUG") != null || System.getProperty("DEBUG") != null;
+
+    public double calculateTaxByStrategy(double baseAmount, ProductCategory category) {
+        if (Objects.isNull(category)) {
+            throw new IllegalArgumentException("Category is null");
+        }
+
+        TaxCalculationStrategy strategy = switch (category) {
+            case STANDARD -> new StandardTaxCalculation();
+            case PREMIUM -> new PremiumTaxCalculation();
+            case LUXURY -> new LuxuryTaxCalculation();
+            default -> throw new IllegalArgumentException("Unsupported product category");
+        };
+
+        double taxAmount = strategy.calculateTax(baseAmount);
+        if (DEBUG) {
+            System.out.println("[CalculateTaxByStrategy] Tax for $" + baseAmount + " (" + category + "): $" + taxAmount);
+        }
+
+        return taxAmount;
+    }
+
+    public double calculateTaxByCategory(double baseAmount, ProductCategory category) {
+        if (Objects.isNull(category)) {
+            throw new IllegalArgumentException("Category is null");
+        }
+
+        TaxCalculator calculator = switch (category) {
+            case STANDARD -> amount1 -> amount1 * 0.10; // 10% tax
+            case PREMIUM -> amount1 -> amount1 * 0.20; // 20% tax
+            case LUXURY -> amount1 -> amount1 * 0.30; // 30% tax
+            default -> throw new IllegalArgumentException("Unsupported product category");
+        };
+
+        double taxAmount = calculator.calculate(baseAmount);
+        if (DEBUG) {
+            System.out.println("[CalculateTaxByCategory] Tax for $" + baseAmount + " (" + category + "): $" + taxAmount);
+        }
+
+        return taxAmount;
+    }
+}

src/main/java/com/shortthirdman/primekit/core/domain/ProductCategory.java

@@ -0,0 +1,6 @@
+package com.shortthirdman.primekit.core.domain;
+
+public enum ProductCategory {
+
+    STANDARD, PREMIUM, LUXURY
+}

src/main/java/com/shortthirdman/primekit/core/funcinterface/TaxCalculator.java

@@ -0,0 +1,7 @@
+package com.shortthirdman.primekit.core.funcinterface;
+
+@FunctionalInterface
+public interface TaxCalculator {
+
+    double calculate(double amount);
+}

src/main/java/com/shortthirdman/primekit/core/strategy/LuxuryTaxCalculation.java

@@ -0,0 +1,9 @@
+package com.shortthirdman.primekit.core.strategy;
+
+public final class LuxuryTaxCalculation implements TaxCalculationStrategy {
+
+    @Override
+    public double calculateTax(double amount) {
+        return amount * 0.30; // 30% tax
+    }
+}

src/main/java/com/shortthirdman/primekit/core/strategy/PremiumTaxCalculation.java

@@ -0,0 +1,9 @@
+package com.shortthirdman.primekit.core.strategy;
+
+public final class PremiumTaxCalculation implements TaxCalculationStrategy {
+
+    @Override
+    public double calculateTax(double amount) {
+        return amount * 0.20; // 20% tax
+    }
+}

src/main/java/com/shortthirdman/primekit/core/strategy/StandardTaxCalculation.java

@@ -0,0 +1,9 @@
+package com.shortthirdman.primekit.core.strategy;
+
+public final class StandardTaxCalculation implements TaxCalculationStrategy {
+
+    @Override
+    public double calculateTax(double amount) {
+        return amount * 0.10; // 10% tax
+    }
+}

src/main/java/com/shortthirdman/primekit/core/strategy/TaxCalculationStrategy.java

@@ -0,0 +1,6 @@
+package com.shortthirdman.primekit.core.strategy;
+
+public sealed interface TaxCalculationStrategy permits StandardTaxCalculation, PremiumTaxCalculation, LuxuryTaxCalculation {
+
+    double calculateTax(double amount);
+}

src/test/java/com/shortthirdman/primekit/coderbyte/PatternAnalyzerTest.java

@@ -0,0 +1,187 @@
+package com.shortthirdman.primekit.coderbyte;
+
+import com.shortthirdman.primekit.core.domain.ProductCategory;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+class PatternAnalyzerTest {
+
+    private static PatternAnalyzer analyzer;
+
+    @BeforeAll
+    static void setUp() {
+        analyzer = new PatternAnalyzer();
+    }
+
+    // ==============================================================
+    //  calculateTaxByStrategy() POSITIVE TESTS
+    // ==============================================================
+
+    @Test
+    @DisplayName("calculateTaxByStrategy - STANDARD tax should be 10%")
+    void testStrategyStandardTax() {
+        double tax = analyzer.calculateTaxByStrategy(100.00, ProductCategory.STANDARD);
+        assertEquals(10.00, tax, 0.001);
+    }
+
+    @Test
+    @DisplayName("calculateTaxByStrategy - PREMIUM tax should be 20%")
+    void testStrategyPremiumTax() {
+        double tax = analyzer.calculateTaxByStrategy(200.00, ProductCategory.PREMIUM);
+        assertEquals(40.00, tax, 0.001);
+    }
+
+    @Test
+    @DisplayName("calculateTaxByStrategy - LUXURY tax should be 30%")
+    void testStrategyLuxuryTax() {
+        double tax = analyzer.calculateTaxByStrategy(300.00, ProductCategory.LUXURY);
+        assertEquals(90.00, tax, 0.001);
+    }
+
+    // ==============================================================
+    //  calculateTaxByCategory() POSITIVE TESTS
+    // ==============================================================
+
+    @Test
+    @DisplayName("calculateTaxByCategory - STANDARD tax should be 10%")
+    void testCategoryStandardTax() {
+        double tax = analyzer.calculateTaxByCategory(100.00, ProductCategory.STANDARD);
+        assertEquals(10.00, tax, 0.001);
+    }
+
+    @Test
+    @DisplayName("calculateTaxByCategory - PREMIUM tax should be 20%")
+    void testCategoryPremiumTax() {
+        double tax = analyzer.calculateTaxByCategory(200.00, ProductCategory.PREMIUM);
+        assertEquals(40.00, tax, 0.001);
+    }
+
+    @Test
+    @DisplayName("calculateTaxByCategory - LUXURY tax should be 30%")
+    void testCategoryLuxuryTax() {
+        double tax = analyzer.calculateTaxByCategory(300.00, ProductCategory.LUXURY);
+        assertEquals(90.00, tax, 0.001);
+    }
+
+
+
+    // ==============================================================
+    //  NEGATIVE INPUT TESTS (invalid numbers)
+    // ==============================================================
+
+    @Test
+    @DisplayName("calculateTaxByStrategy - negative amount allowed but calculation valid")
+    void testStrategyNegativeAmount() {
+        double tax = analyzer.calculateTaxByStrategy(-100.00, ProductCategory.STANDARD);
+        assertEquals(-10.00, tax, 0.001);
+    }
+
+    @Test
+    @DisplayName("calculateTaxByCategory - negative amount allowed but calculation valid")
+    void testCategoryNegativeAmount() {
+        double tax = analyzer.calculateTaxByCategory(-100.00, ProductCategory.LUXURY);
+        assertEquals(-30.00, tax, 0.001);
+    }
+
+    // ==============================================================
+    //  EDGE CASES
+    // ==============================================================
+
+    @Test
+    @DisplayName("calculateTaxByStrategy - zero amount should return zero")
+    void testStrategyZeroAmount() {
+        double tax = analyzer.calculateTaxByStrategy(0.0, ProductCategory.PREMIUM);
+        assertEquals(0.0, tax);
+    }
+
+    @Test
+    @DisplayName("calculateTaxByCategory - zero amount should return zero")
+    void testCategoryZeroAmount() {
+        double tax = analyzer.calculateTaxByCategory(0.0, ProductCategory.LUXURY);
+        assertEquals(0.0, tax);
+    }
+
+    @Test
+    @DisplayName("calculateTaxByStrategy - very large amount precision test")
+    void testStrategyLargeAmount() {
+        double tax = analyzer.calculateTaxByStrategy(1_000_000.0, ProductCategory.LUXURY);
+        assertEquals(300_000.0, tax);
+    }
+
+    @Test
+    @DisplayName("calculateTaxByCategory - very large amount precision test")
+    void testCategoryLargeAmount() {
+        double tax = analyzer.calculateTaxByCategory(1_000_000.0, ProductCategory.STANDARD);
+        assertEquals(100_000.0, tax);
+    }
+
+    // ==============================================================
+    //  NULL CATEGORY (EXCEPTION TESTS)
+    // ==============================================================
+
+    @Test
+    @DisplayName("calculateTaxByStrategy - null category throws IllegalArgumentException")
+    void testStrategyNullCategory() {
+        Assertions.assertThrows(IllegalArgumentException.class,
+                () -> analyzer.calculateTaxByStrategy(50.0, null));
+    }
+
+    @Test
+    @DisplayName("calculateTaxByCategory - null category throws IllegalArgumentException")
+    void testCategoryNullCategory() {
+        Assertions.assertThrows(IllegalArgumentException.class,
+                () -> analyzer.calculateTaxByCategory(50.0, null));
+    }
+
+    // ==============================================================
+    //  UNSUPPORTED CATEGORY (just in case enum grows)
+    // ==============================================================
+
+    @Test
+    @DisplayName("calculateTaxByStrategy - unsupported category throws IllegalArgumentException")
+    void testStrategyUnsupportedCategory() {
+        Assertions.assertThrows(IllegalArgumentException.class,
+                () -> analyzer.calculateTaxByStrategy(100.0, ProductCategory.valueOf("UNKNOWN")));
+    }
+
+    @Test
+    @DisplayName("calculateTaxByCategory - unsupported category throws IllegalArgumentException")
+    void testCategoryUnsupportedCategory() {
+        Assertions.assertThrows(IllegalArgumentException.class,
+                () -> analyzer.calculateTaxByCategory(100.0, ProductCategory.valueOf("UNKNOWN")));
+    }
+
+    @Test
+    @DisplayName("Standard category applies 10% tax")
+    void standardCategoryApplies10PercentTax() {
+        PatternAnalyzer analyzer = new PatternAnalyzer();
+
+        double result = analyzer.calculateTaxByStrategy(100, ProductCategory.STANDARD);
+
+        assertEquals(10.0, result);
+    }
+
+    @Test
+    @DisplayName("Premium category applies 20% tax")
+    void premiumCategoryApplies20PercentTax() {
+        PatternAnalyzer analyzer = new PatternAnalyzer();
+
+        double result = analyzer.calculateTaxByStrategy(100, ProductCategory.PREMIUM);
+
+        assertEquals(20.0, result);
+    }
+
+    @Test
+    @DisplayName("Luxury category applies 30% tax")
+    void luxuryCategoryApplies30PercentTax() {
+        PatternAnalyzer analyzer = new PatternAnalyzer();
+
+        double result = analyzer.calculateTaxByStrategy(100, ProductCategory.LUXURY);
+
+        assertEquals(30.0, result);
+    }
+}