feat(queryAsPath): implement basic logic UNTESTED

src/main/java/io/github/js0ny/ilp_coursework/service/DroneInfoService.java

@@ -6,6 +6,9 @@ import java.util.Arrays;
 import org.springframework.stereotype.Service;
 import org.springframework.web.client.RestTemplate;
 
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+
 @Service
 public class DroneInfoService {
 
@@ -95,12 +98,43 @@ public class DroneInfoService {
         URI droneUrl = URI.create(baseUrl).resolve(dronesEndpoint);
         DroneDto[] drones = restTemplate.getForObject(
                 droneUrl,
-            DroneDto[].class
+                DroneDto[].class);
-        );
 
-        // TODO: Logic unimplemented
+        if (drones == null) {
             return new int[] {};
         }
 
-    public int[] dronesMatchesRequirements()
+        // Use Jackson's ObjectMapper to convert DroneDto to JsonNode for dynamic
+        // querying
+        ObjectMapper mapper = new ObjectMapper();
+
+        return Arrays.stream(drones)
+                .filter(drone -> {
+                    JsonNode node = mapper.valueToTree(drone);
+                    JsonNode attrNode = node.findValue(attrName);
+                    if (attrNode != null) {
+                        return isValueMatched(attrNode, attrVal);
+                    } else {
+                        return false;
+                    }
+                })
+                .mapToInt(drone -> Integer.parseInt(drone.id()))
+                .toArray();
+    }
+
+    private boolean isValueMatched(JsonNode node, String attrVal) {
+        if (node.isTextual()) {
+            return node.asText().equals(attrVal);
+        } else if (node.isNumber()) {
+            return Double.compare(node.asDouble(), Double.parseDouble(attrVal)) == 0;
+        } else if (node.isBoolean()) {
+            return node.asText().equals(attrVal);
+        } else {
+            return false;
+        }
+    }
+
+    public int[] dronesMatchesRequirements() {
+        return new int[] {};
+    };
 }