Add skin cropping

src/main/java/me/braydon/mc/common/PlayerUtils.java

@@ -0,0 +1,67 @@
+package me.braydon.mc.common;
+
+import lombok.NonNull;
+import lombok.SneakyThrows;
+import lombok.experimental.UtilityClass;
+import me.braydon.mc.model.Skin;
+
+import javax.imageio.ImageIO;
+import java.awt.geom.AffineTransform;
+import java.awt.image.AffineTransformOp;
+import java.awt.image.BufferedImage;
+import java.io.ByteArrayOutputStream;
+import java.net.URL;
+
+/**
+ * @author Braydon
+ */
+@UtilityClass
+public final class PlayerUtils {
+    private static final int SKIN_TEXTURE_SIZE = 64; // The skin of a skin texture
+
+    /**
+     * Get the head texture of a skin.
+     *
+     * @param skin the skin to get the head texture from
+     * @param size the size to scale the head texture to
+     * @return the head texture of the skin
+     */
+    @SneakyThrows
+    public static byte[] getHeadTexture(@NonNull Skin skin, int size) {
+        return getSkinPartTexture(skin, 8, 8, SKIN_TEXTURE_SIZE / 8, SKIN_TEXTURE_SIZE / 8, size);
+    }
+
+    /**
+     * Get the texture of a specific part of a skin.
+     *
+     * @param skin the skin to get the part from
+     * @param x the x position of the part
+     * @param y the y position of the part
+     * @param width the width of the part
+     * @param height the height of the part
+     * @param size the size to scale the part to
+     * @return the texture of the skin part
+     */
+    @SneakyThrows
+    public static byte[] getSkinPartTexture(@NonNull Skin skin, int x, int y, int width, int height, int size) {
+        BufferedImage skinImage = ImageIO.read(new URL(skin.getUrl())); // The skin texture
+
+        // Create a new BufferedImage for the part of the skin texture
+        BufferedImage headTexture = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
+
+        // Crop just the part we want based on our x, y, width, and height
+        headTexture.getGraphics().drawImage(skinImage, 0, 0, width, height, x, y, x + width, y + height, null);
+
+        // Scale the skin part texture
+        double scale = (double) size / width;
+        AffineTransform transform = AffineTransform.getScaleInstance(scale, scale);
+        headTexture = new AffineTransformOp(transform, AffineTransformOp.TYPE_NEAREST_NEIGHBOR).filter(headTexture, null);
+
+        // Convert BufferedImage to byte array
+        try (ByteArrayOutputStream outputStream = new ByteArrayOutputStream()) {
+            ImageIO.write(headTexture, "png", outputStream);
+            outputStream.flush();
+            return outputStream.toByteArray();
+        }
+    }
+}

src/main/java/me/braydon/mc/controller/PlayerController.java

@@ -10,7 +10,6 @@ import me.braydon.mc.model.Skin;
 import me.braydon.mc.model.cache.CachedPlayer;
 import me.braydon.mc.service.MojangService;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.core.io.ByteArrayResource;
 import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
@@ -25,6 +24,9 @@ import org.springframework.web.bind.annotation.*;
 @RequestMapping(value = "/player", produces = MediaType.APPLICATION_JSON_VALUE)
 @Log4j2(topic = "Player Controller")
 public final class PlayerController {
+    private static final int DEFAULT_HEAD_SIZE = 128;
+    private static final int MAX_HEAD_SIZE = 512;
+
     /**
      * The Mojang service to use for player information.
      */
@@ -60,15 +62,23 @@ public final class PlayerController {
      *
      * @param query the query to search for the player by
      * @param extension the head image extension
+     * @param size the size of the head image
      * @return the head texture
      * @throws BadRequestException if the extension is invalid
      */
     @GetMapping("/head/{query}.{extension}")
     @ResponseBody
-    public ResponseEntity<ByteArrayResource> getHead(@PathVariable @NonNull String query, @PathVariable @NonNull String extension) throws BadRequestException {
+    public ResponseEntity<byte[]> getHead(@PathVariable @NonNull String query, @PathVariable @NonNull String extension,
+                                          @RequestParam(required = false) Integer size
+    ) throws BadRequestException {
         if ((extension = extension.trim()).isBlank()) { // Invalid extension
             throw new BadRequestException("Invalid extension");
         }
+        if (size == null || size <= 0) { // Invalid size
+            size = DEFAULT_HEAD_SIZE;
+        }
+        size = Math.min(size, MAX_HEAD_SIZE); // Limit the size to 512
+
         Skin target = null; // The target skin to get the head of
         try {
             CachedPlayer player = mojangService.getPlayer(query, false); // Retrieve the player
@@ -82,6 +92,6 @@ public final class PlayerController {
         // Return the head texture
         return ResponseEntity.ok()
                 .contentType(extension.equalsIgnoreCase("png") ? MediaType.IMAGE_PNG : MediaType.IMAGE_JPEG)
-                .body(new ByteArrayResource(PlayerUtils.getSkinPartTexture(target)));
+                .body(PlayerUtils.getHeadTexture(target, size));
     }
 }