add new prediction service

src/main/java/com/safeqr/app/prediction/service/PredictionService.java

@@ -0,0 +1,63 @@
+package com.safeqr.app.prediction.service;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.safeqr.app.prediction.model.URLFeatures;
+import com.safeqr.app.qrcode.model.URLModel;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.stereotype.Service;
+import org.springframework.web.client.RestTemplate;
+import org.springframework.http.ResponseEntity;
+import org.springframework.http.HttpEntity;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+import org.springframework.http.MediaType;
+
+import static com.safeqr.app.constants.APIConstants.PREDICTION_API_URL;
+
+@Service
+public class PredictionService {
+    private static final Logger logger = LoggerFactory.getLogger(PredictionService.class);
+
+    private final RestTemplate restTemplate;
+    private final ObjectMapper objectMapper;
+
+    public PredictionService(RestTemplate restTemplate, ObjectMapper objectMapper) {
+        this.restTemplate = restTemplate;
+        this.objectMapper = objectMapper;
+    }
+
+    public String predict(URLModel urlModel) {
+        // Convert URLModel to URLFeatures
+        URLFeatures features = URLFeatures.fromEntity(urlModel);
+        logger.info("Prediction request: {}", features);
+
+        // Prepare the HTTP headers
+        HttpHeaders headers = new HttpHeaders();
+        headers.setContentType(MediaType.APPLICATION_JSON);
+
+        // Create the HTTP entity containing the features and headers
+        HttpEntity<URLFeatures> requestEntity = new HttpEntity<>(features, headers);
+
+        // Make the HTTP POST request to the FastAPI prediction endpoint
+        ResponseEntity<String> response = restTemplate.exchange(
+                PREDICTION_API_URL,
+                HttpMethod.POST,
+                requestEntity,
+                String.class
+        );
+
+        // Use ObjectMapper to deserialize the response and automatically remove quotes
+        String prediction = response.getBody();
+        try {
+            prediction = objectMapper.readValue(prediction, String.class);
+        } catch (Exception e) {
+            logger.error("Failed to parse prediction response", e);
+            prediction = "Unknown";
+        }
+        logger.info("Prediction response: {}", prediction);
+
+        // Return the prediction
+        return prediction;
+    }
+}