Add 2 vs 2 win rates

src/main/java/org/kickerelo/kickerelo/layout/KickerAppLayout.java

@@ -39,7 +39,8 @@ public class KickerAppLayout extends AppLayout {
         nav2.setCollapsible(true);
         nav2.addItem(new SideNavItem("Ergebnis eintragen", Enter2vs2View.class, VaadinIcon.EDIT.create()),
                 new SideNavItem("ELO-Graph", Graph2vs2View.class, VaadinIcon.BAR_CHART.create()),
-                new SideNavItem("Historie", History2vs2View.class, VaadinIcon.RECORDS.create()));
+                new SideNavItem("Historie", History2vs2View.class, VaadinIcon.RECORDS.create()),
+                new SideNavItem("Statistik", Stat2vs2View.class, VaadinIcon.ABACUS.create()));
 
 
         Image githubLogo = new Image("github-mark.png", "Github");

src/main/java/org/kickerelo/kickerelo/repository/Ergebnis2vs2Repository.java

@@ -1,9 +1,14 @@
 package org.kickerelo.kickerelo.repository;
 
 import org.kickerelo.kickerelo.data.Ergebnis2vs2;
+import org.kickerelo.kickerelo.data.Spieler;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.stereotype.Repository;
 
 @Repository
 public interface Ergebnis2vs2Repository extends JpaRepository<Ergebnis2vs2, Long> {
+    int countByGewinnerHinten(Spieler gewinnerHinten);
+    int countByGewinnerVorn(Spieler gewinnerVon);
+    int countByVerliererHinten(Spieler verliererHinten);
+    int countByVerliererVorn(Spieler verlierVon);
 }

src/main/java/org/kickerelo/kickerelo/service/Stat2vs2Service.java

@@ -0,0 +1,45 @@
+package org.kickerelo.kickerelo.service;
+
+import org.kickerelo.kickerelo.data.Spieler;
+import org.kickerelo.kickerelo.exception.NoSuchPlayerException;
+import org.kickerelo.kickerelo.repository.Ergebnis2vs2Repository;
+import org.kickerelo.kickerelo.repository.SpielerRepository;
+import org.kickerelo.kickerelo.util.Position;
+import org.springframework.stereotype.Service;
+
+import java.util.Optional;
+
+@Service
+public class Stat2vs2Service {
+    Ergebnis2vs2Repository ergebnis2vs2Repository;
+    SpielerRepository spielerRepository;
+
+    public Stat2vs2Service(Ergebnis2vs2Repository ergebnis2vs2Repository, SpielerRepository spielerRepository) {
+        this.ergebnis2vs2Repository = ergebnis2vs2Repository;
+        this.spielerRepository = spielerRepository;
+    }
+
+    public Float getWinrate(Spieler s, Position p) {
+        int wins, losses;
+        switch (p) {
+            case BACK:
+                wins = ergebnis2vs2Repository.countByGewinnerHinten(s);
+                losses = ergebnis2vs2Repository.countByVerliererHinten(s);
+                break;
+            case FRONT:
+                wins = ergebnis2vs2Repository.countByGewinnerVorn(s);
+                losses = ergebnis2vs2Repository.countByVerliererVorn(s);
+                break;
+            default:
+                wins = 0;
+                losses = 0;
+        }
+        return (float) (100 * wins) / (wins+losses);
+    }
+
+    public Float getWinrate(String playerName, Position p) {
+        Optional<Spieler> spieler = spielerRepository.findByName(playerName);
+        if (spieler.isEmpty()) throw new NoSuchPlayerException(playerName);
+        return getWinrate(spieler.get(), p);
+    }
+}

src/main/java/org/kickerelo/kickerelo/util/Position.java

@@ -0,0 +1,5 @@
+package org.kickerelo.kickerelo.util;
+
+public enum Position {
+    FRONT, BACK
+}

src/main/java/org/kickerelo/kickerelo/views/Stat2vs2View.java

@@ -0,0 +1,42 @@
+package org.kickerelo.kickerelo.views;
+
+import com.vaadin.flow.component.combobox.ComboBox;
+import com.vaadin.flow.component.html.H2;
+import com.vaadin.flow.component.html.Paragraph;
+import com.vaadin.flow.component.orderedlayout.VerticalLayout;
+import com.vaadin.flow.router.Route;
+import org.kickerelo.kickerelo.data.Spieler;
+import org.kickerelo.kickerelo.service.KickerEloService;
+import org.kickerelo.kickerelo.service.Stat2vs2Service;
+import org.kickerelo.kickerelo.util.Position;
+
+@Route("stat2vs2")
+public class Stat2vs2View extends VerticalLayout {
+    Stat2vs2Service stat2vs2Service;
+    KickerEloService kickerEloService;
+    H2 subheading;
+    ComboBox<Spieler> selector;
+    Paragraph winrateBack;
+    Paragraph winrateFront;
+    public Stat2vs2View(Stat2vs2Service service, KickerEloService kickerService) {
+        this.stat2vs2Service = service;
+        this.kickerEloService = kickerService;
+        subheading = new H2("2 vs 2 Ergebnis");
+        selector = new ComboBox<>("Spieler");
+        selector.setItems(kickerService.getSpielerEntities());
+        selector.addValueChangeListener(event -> {
+            updateData(selector.getValue());
+        });
+        winrateBack = new Paragraph("");
+        winrateFront = new Paragraph("");
+
+        add(subheading, selector, winrateBack, winrateFront);
+    }
+
+    private void updateData(Spieler s) {
+        Float rateBack = stat2vs2Service.getWinrate(s, Position.BACK);
+        Float rateFront = stat2vs2Service.getWinrate(s, Position.FRONT);
+        winrateBack.setText("Winrate hinten: " + (rateBack.isNaN() ? "-" : rateBack));
+        winrateFront.setText("Winrate vorne: " + (rateFront.isNaN() ? "-" : rateFront));
+    }
+}