added method checkoffer

src/main/java/de/rwu/easydrop/core/OfferReviewer.java

@@ -1,23 +1,80 @@
 package de.rwu.easydrop.core;
 
 import de.rwu.easydrop.model.Offer;
+import de.rwu.easydrop.model.Product;
+import de.rwu.easydrop.model.Product.webshop;
+
 import java.util.List;
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
 import java.util.ArrayList;
 
 public class OfferReviewer {
 
-    public OfferReviewer(/*OfferReader/retriever for database? */){
+    /**
+     *  OfferReviewer.
+     * @return list of all items that need to be changed
+     */
+    public List<Offer> checkOffers(/*OfferReader/retriever for database? */) {
 
-    }
+        Connection connection = null;
+        Statement statement = null;
+        ResultSet resultSet = null;
+        List<Product> changedProducts = new ArrayList<>();
 
-    public List<Offer> runReviewer() {
-        /*
-         * Liest eingestellte Angebote in der Datenbank
-         * Prüft Zielplattformen der SourceProducts, ob diese noch verfügbar sind (Issue#12) bzw. ob sie sich im Preis geändert haben
-         * Gibt Liste zurück von Offers, die geändert werden müssen, wird übergeben an OfferUpdater mit availability true oder false
-         */
+         try {
+            // Establish the database connection
+            connection = DriverManager.getConnection("jdbc:sqlite:persistence.db");
+
+            // Create a SQL statement
+            statement = connection.createStatement();
+
+            // Execute the query to retrieve the entries
+            String query = "SELECT dataOrigin, productId, currentPrice FROM table";
+            resultSet = statement.executeQuery(query);
+
+            // Process the retrieved entries
+            while (resultSet.next()) {
+                String webshop = resultSet.getString("webshop");
+                String dataOrigin = resultSet.getString("data_origin");
+                String productId = resultSet.getString("productId");
+                double currentPrice = resultSet.getDouble("currentPrice");
+                String merchant = resultSet.getString("merchant");
+                double deliveryPrice = resultSet.getDouble("delivery_price");
+                boolean available = resultSet.getBoolean("available");
+
+                // Call the API to get the current price
+                double apiPrice = getPriceFromAPI(productId);
+
+                // Compare the prices
+                if (currentPrice != apiPrice) {
+                    // Price has changed, create a Product object and add it to the changedProducts list
+                    Product product = new Product(webshop, dataOrigin, productId, currentPrice,
+                    merchant, deliveryPrice, available);
+                    changedProducts.add(product);
+                }
+            }
+        } catch (SQLException e) {
+            e.printStackTrace();
+        } finally {
+            // Close the resources (resultSet, statement, connection) in a finally block
+            try {
+                if (resultSet != null) {
+                    resultSet.close();
+                }
+                if (statement != null) {
+                    statement.close();
+                }
+                if (connection != null) {
+                    connection.close();
+                }
+            } catch (SQLException e) {
+                e.printStackTrace();
+            }
+        }
         return new ArrayList<Offer>();
-
     }
-    
 }