added modified data driven version

src/main/java/com/pfefferminzia/petinsurance/Main.java

@@ -1,13 +0,0 @@
-package com.pfefferminzia.petinsurance;
-
-import java.time.LocalDate;
-import com.pfefferminzia.petinsurance.animals.Dog;
-import com.pfefferminzia.petinsurance.calculations.InsuranceContract;
-import com.pfefferminzia.petinsurance.tariffs.Tariff;
-
-public class Main {
-    public static void main(String[] args) {
-        System.out.println(new InsuranceContract(new Dog(LocalDate.of(2025, 1, 1), "Dackel"),
-                LocalDate.of(2026, 1, 1), Tariff.OPTIMAL));
-    }
-}

src/main/java/com/pfefferminzia/petinsurance/animals/Animal.java

@@ -1,15 +1,8 @@
 package com.pfefferminzia.petinsurance.animals;
 
-import java.math.BigDecimal;
 import java.time.LocalDate;
 
 public sealed interface Animal permits Dog, Cat, SmallAnimal {
 
     LocalDate birthday();
-
-    BigDecimal getBaseInsuranceSum();
-
-    default BigDecimal getPremiumAdjustment() {
-        return BigDecimal.ZERO;
-    }
 }

src/main/java/com/pfefferminzia/petinsurance/animals/Cat.java

@@ -1,12 +1,6 @@
 package com.pfefferminzia.petinsurance.animals;
 
-import java.math.BigDecimal;
 import java.time.LocalDate;
 
 public final record Cat(LocalDate birthday) implements Animal {
-
-    @Override
-    public BigDecimal getBaseInsuranceSum() {
-        return BigDecimal.valueOf(2000.0);
-    }
 }

src/main/java/com/pfefferminzia/petinsurance/animals/Dog.java

@@ -1,18 +1,11 @@
 package com.pfefferminzia.petinsurance.animals;
 
-import java.math.BigDecimal;
 import java.time.LocalDate;
-import com.pfefferminzia.petinsurance.tariffs.BreedPremiumAdjustment;
 
 public final record Dog(LocalDate birthday, String breed) implements Animal {
 
     @Override
-    public BigDecimal getBaseInsuranceSum() {
-        return BigDecimal.valueOf(2500.0);
-    }
-
-    @Override
-    public BigDecimal getPremiumAdjustment() {
-        return BreedPremiumAdjustment.forBreed(breed);
+    public String breed() {
+        return (this.breed == null || this.breed.isBlank()) ? "" : this.breed;
     }
 }

src/main/java/com/pfefferminzia/petinsurance/animals/SmallAnimal.java

@@ -1,12 +1,6 @@
 package com.pfefferminzia.petinsurance.animals;
 
-import java.math.BigDecimal;
 import java.time.LocalDate;
 
 public final record SmallAnimal(LocalDate birthday) implements Animal {
-
-    @Override
-    public BigDecimal getBaseInsuranceSum() {
-        return BigDecimal.valueOf(1000.0);
-    }
 }

src/main/java/com/pfefferminzia/petinsurance/calculations/Calculations.java

@@ -3,23 +3,34 @@ package com.pfefferminzia.petinsurance.calculations;
 import java.math.BigDecimal;
 import java.time.LocalDate;
 import java.time.temporal.ChronoUnit;
-import com.pfefferminzia.petinsurance.tariffs.AgeTariff;
-import com.pfefferminzia.petinsurance.tariffs.Tariff;
+import com.pfefferminzia.petinsurance.animals.*;
+import com.pfefferminzia.petinsurance.tariffs.TariffConfiguration;
+import com.pfefferminzia.petinsurance.tariffs.TariffOption;
 
 public class Calculations {
 
-    public CalculationResult result(InsuranceContract contract) {
+    private final TariffConfiguration tariffConfig;
 
-        Tariff tariff = contract.tariff();
+    public Calculations(TariffConfiguration tariffConfig) {
+        this.tariffConfig = tariffConfig;
+    }
 
-        BigDecimal insuranceSum =
-                getInsuranceSum(contract.animal().getBaseInsuranceSum(), tariff.getRate());
+    public CalculationResult calculateInsuranceSumAndYearlyPremium(InsuranceContract contract) {
 
-        BigDecimal ageFactor =
-                ageFactorLookup(contract.animal().birthday(), contract.insuranceStartDate());
+        Animal animal = contract.animal();
+        LocalDate insuranceStartDate = contract.insuranceStartDate();
 
+        TariffOption tariff =
+                tariffConfig.getTariffFactor(contract.tariffName(), insuranceStartDate);
 
-        BigDecimal breedPremiumAdjustment = contract.animal().getPremiumAdjustment();
+        String speciesKey = animal.getClass().getSimpleName().toUpperCase();
+        BigDecimal baseInsuranceSum = tariffConfig.getAnimalBaseSum(speciesKey);
+
+        BigDecimal insuranceSum = getInsuranceSum(baseInsuranceSum, tariff.factor());
+
+        BigDecimal ageFactor = ageFactorLookup(contract.animal().birthday(), insuranceStartDate);
+
+        BigDecimal breedPremiumAdjustment = breedFactorLookup(animal);
 
         BigDecimal yearlyPremium = insuranceSum.multiply(ageFactor)
                 .multiply(BigDecimal.ONE.add(breedPremiumAdjustment));
@@ -27,18 +38,22 @@ public class Calculations {
         return new CalculationResult(insuranceSum, yearlyPremium);
     }
 
-    BigDecimal getInsuranceSum(BigDecimal baseInsuranceSum, BigDecimal tariffRate) {
+    private BigDecimal getInsuranceSum(BigDecimal baseInsuranceSum, BigDecimal tariffRate) {
+
         return baseInsuranceSum.multiply(tariffRate);
     }
 
-    BigDecimal ageFactorLookup(LocalDate birthday, LocalDate insuranceStartDate) {
-        if (insuranceStartDate.isBefore(birthday)) {
-            throw new IllegalArgumentException(
-                    "Start der Versicherung kann nicht vor dem Geburtstag sein.");
-        }
+    private BigDecimal ageFactorLookup(LocalDate birthday, LocalDate insuranceStartDate) {
 
         long exactYears = ChronoUnit.YEARS.between(birthday, insuranceStartDate);
 
-        return AgeTariff.getFactorForAge(Math.toIntExact(exactYears));
+        return tariffConfig.getAgeFactor(Math.toIntExact(exactYears));
+    }
+
+    private BigDecimal breedFactorLookup(Animal animal) {
+        return switch (animal) {
+            case Dog dog -> tariffConfig.getBreedFactor(dog.breed());
+            case Cat _,SmallAnimal _ -> BigDecimal.ZERO;
+        };
     }
 }

src/main/java/com/pfefferminzia/petinsurance/calculations/InsuranceContract.java

@@ -5,21 +5,28 @@ import java.util.ArrayList;
 import java.util.List;
 import com.pfefferminzia.petinsurance.animals.Animal;
 import com.pfefferminzia.petinsurance.exception.InvalidInsuranceContractException;
-import com.pfefferminzia.petinsurance.tariffs.Tariff;
 
-public record InsuranceContract(Animal animal, LocalDate insuranceStartDate, Tariff tariff) {
-
-    private static final LocalDate PREMIUM_AVAILABLE_FROM = LocalDate.of(2026, 7, 1);
+public record InsuranceContract(Animal animal, LocalDate insuranceStartDate, String tariffName) {
 
     public InsuranceContract {
+
         List<String> violations = new ArrayList<>();
 
-        if (animal.birthday().isAfter(insuranceStartDate)) {
-            violations.add("Start der Versicherung kann nicht vor dem Geburtstag sein.");
+        if (animal() == null) {
+            violations.add("Animal darf nicht leer sein");
         }
 
-        if (insuranceStartDate.isBefore(PREMIUM_AVAILABLE_FROM) && tariff == Tariff.PREMIUM) {
-            violations.add("Die Premium Tarifvariante ist nicht vor dem 1. Juli 2026 verfügbar.");
+        if (tariffName == null) {
+            violations.add("Tarif darf nicht leer sein");
+        }
+
+        if (insuranceStartDate == null) {
+            violations.add("Versicherungsstart darf nicht leer sein");
+        }
+
+        if (animal() != null && insuranceStartDate != null
+                && animal.birthday().isAfter(insuranceStartDate)) {
+            violations.add("Start der Versicherung kann nicht vor dem Geburtstag sein.");
         }
 
         if (!violations.isEmpty()) {

src/main/java/com/pfefferminzia/petinsurance/tariffs/AgeTariff.java

@@ -1,27 +0,0 @@
-package com.pfefferminzia.petinsurance.tariffs;
-
-import java.math.BigDecimal;
-
-public enum AgeTariff {
-    UP_TO_TWO(2, new BigDecimal("0.2")), UP_TO_FIVE(5, new BigDecimal("0.25")), UP_TO_SEVEN(7,
-            new BigDecimal("0.28")), OVER_SEVEN(Integer.MAX_VALUE, new BigDecimal("0.3"));
-
-    private final int maxAge;
-
-    private final BigDecimal factor;
-
-    private AgeTariff(int maxAge, BigDecimal factor) {
-        this.maxAge = maxAge;
-        this.factor = factor;
-    }
-
-    public static BigDecimal getFactorForAge(int age) {
-        for (AgeTariff rate : values()) {
-            if (age <= rate.maxAge) {
-                return rate.factor;
-            }
-        }
-        throw new AssertionError("Unexpected age: " + age);
-    }
-
-}

src/main/java/com/pfefferminzia/petinsurance/tariffs/BreedPremiumAdjustment.java

@@ -1,18 +0,0 @@
-package com.pfefferminzia.petinsurance.tariffs;
-
-import java.math.BigDecimal;
-import java.util.Map;
-
-public final class BreedPremiumAdjustment {
-    
-    private static final Map<String, BigDecimal> ADJUSTMENTS = Map.of(
-        "Dackel", new BigDecimal("-0.1"),
-        "Bernhardiner", new BigDecimal("0.1")
-    );
-
-    public static BigDecimal forBreed(String breed) {
-        return ADJUSTMENTS.getOrDefault(breed, BigDecimal.ZERO);
-    }
-
-    private BreedPremiumAdjustment() {}
-}

src/main/java/com/pfefferminzia/petinsurance/tariffs/Tariff.java

@@ -1,17 +0,0 @@
-package com.pfefferminzia.petinsurance.tariffs;
-
-import java.math.BigDecimal;
-
-public enum Tariff {
-    KOMPAKT(BigDecimal.ONE), OPTIMAL(new BigDecimal("1.2")), PREMIUM(new BigDecimal("1.4"));
-
-    private final BigDecimal rate;
-
-    private Tariff(BigDecimal rate) {
-        this.rate = rate;
-    }
-
-    public BigDecimal getRate() {
-        return rate;
-    }
-}

src/main/java/com/pfefferminzia/petinsurance/tariffs/TariffConfiguration.java

@@ -0,0 +1,74 @@
+package com.pfefferminzia.petinsurance.tariffs;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.Collections;
+import java.util.Map;
+import java.util.NavigableMap;
+import java.util.TreeMap;
+
+public record TariffConfiguration(Map<String, BigDecimal> animalBaseSums,
+        Map<String, TariffOption> tariffs, NavigableMap<Integer, BigDecimal> ageFactors,
+        Map<String, BigDecimal> breedFactors) {
+
+    public TariffConfiguration {
+        animalBaseSums = Collections.unmodifiableMap(animalBaseSums);
+        tariffs = Collections.unmodifiableMap(tariffs);
+        ageFactors = Collections.unmodifiableNavigableMap(new TreeMap<>(ageFactors));
+        breedFactors = Collections.unmodifiableMap(breedFactors);
+    }
+
+    public BigDecimal getAnimalBaseSum(String species) {
+        if (species == null || species.isBlank()) {
+            throw new IllegalArgumentException("Tierart darf nicht leer oder null sein.");
+        }
+
+        String normalizedKey = species.trim().toUpperCase();
+        BigDecimal baseSum = animalBaseSums.get(normalizedKey);
+
+        if (baseSum == null) {
+            throw new IllegalArgumentException(
+                    "Keine Basis-Versicherungssumme für Tierart konfiguriert: " + species);
+        }
+
+        return baseSum;
+    }
+
+    public TariffOption getTariffFactor(String tariffName, LocalDate startDate) {
+
+        TariffOption option = tariffs.get(tariffName.toUpperCase());
+
+        if (option == null) {
+            throw new IllegalArgumentException("Unbekannte Tarifvariante: " + tariffName);
+        }
+
+        if (!option.isAvailableAt(startDate)) {
+            throw new IllegalStateException("Die Tarifvariante " + tariffName + " ist zum "
+                    + startDate + " noch nicht verfügbar.");
+        }
+
+        return option;
+    }
+
+    public BigDecimal getAgeFactor(int age) {
+        if (age < 0) {
+            throw new IllegalArgumentException("Alter kann nicht negativ sein: " + age);
+        }
+
+        var entry = ageFactors.ceilingEntry(age);
+        if (entry == null) {
+            throw new IllegalStateException("Alter überschreitet maximal zulässigen Systemwert.");
+        }
+
+        return entry.getValue();
+    }
+
+    public BigDecimal getBreedFactor(String breed) {
+        if (breed == null || breed.isBlank()) {
+            return BigDecimal.ZERO;
+        }
+
+        return breedFactors.getOrDefault(breed.trim().toUpperCase(), BigDecimal.ZERO);
+    }
+
+}

src/main/java/com/pfefferminzia/petinsurance/tariffs/TariffLoader.java

@@ -0,0 +1,98 @@
+package com.pfefferminzia.petinsurance.tariffs;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.math.BigDecimal;
+import java.time.LocalDate;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.NavigableMap;
+import java.util.Properties;
+import java.util.TreeMap;
+import java.util.stream.Collectors;
+
+public final class TariffLoader {
+    private static final String CONFIG_FILE_NAME = "tariff.properties";
+
+    public static TariffConfiguration loadFromFile() {
+        Properties props = new Properties();
+
+        try (InputStream input =
+                TariffLoader.class.getClassLoader().getResourceAsStream(CONFIG_FILE_NAME)) {
+            if (input == null) {
+                throw new IllegalStateException(
+                        "Konfigurationsdatei nicht verfügbar: " + CONFIG_FILE_NAME);
+            }
+            props.load(input);
+        } catch (IOException e) {
+            throw new IllegalStateException("Fehler beim Auslesen der Tarif-Konfigurationsdatei.",
+                    e);
+        }
+
+        return new TariffConfiguration(animalBaseSums(props), tariffs(props), ageFactors(props),
+                breedFactors(props));
+
+    }
+
+    private static Map<String, BigDecimal> animalBaseSums(Properties props) {
+
+        Map<String, BigDecimal> baseSums = new HashMap<>();
+
+        for (String key : props.stringPropertyNames()) {
+            if (key.startsWith("baseSum.")) {
+                String animal = key.substring("baseSum.".length()).toUpperCase();
+                BigDecimal baseSum = new BigDecimal(props.getProperty(key));
+                baseSums.put(animal, baseSum);
+            }
+        }
+        return baseSums;
+    }
+
+    private static Map<String, TariffOption> tariffs(Properties props) {
+
+        return props.stringPropertyNames().stream().filter(key -> key.startsWith("tariffs."))
+                .map(key -> {
+                    String name = key.substring("tariffs.".length()).toUpperCase();
+                    String[] values = props.getProperty(key).split(",");
+                    BigDecimal factor = new BigDecimal(values[0]);
+                    LocalDate availableFrom = LocalDate.parse(values[1]);
+                    return new TariffOption(name, factor, availableFrom);
+                }).collect(Collectors.toMap(TariffOption::name, tariff -> tariff));
+    }
+
+    private static NavigableMap<Integer, BigDecimal> ageFactors(Properties props) {
+
+        NavigableMap<Integer, BigDecimal> ageFactors = new TreeMap<>();
+
+        for (String key : props.stringPropertyNames()) {
+            if (key.startsWith("age.")) {
+                Integer age = Integer.parseInt(key.replace("age.", ""));
+                BigDecimal factor = new BigDecimal(props.getProperty(key));
+                ageFactors.put(age, factor);
+            }
+        }
+
+        String rawElderly = props.getProperty("elderlyFactor");
+        if (rawElderly == null) {
+            throw new IllegalStateException("Pflichtkonfiguration 'elderlyFactor' fehlt.");
+        }
+        ageFactors.put(Integer.MAX_VALUE, new BigDecimal(rawElderly));
+        return ageFactors;
+    }
+
+    private static Map<String, BigDecimal> breedFactors(Properties props) {
+
+        Map<String, BigDecimal> breedFactors = new HashMap<>();
+
+        for (String key : props.stringPropertyNames()) {
+            if (key.startsWith("breed.")) {
+                String name = key.substring("breed.".length()).toUpperCase();
+                BigDecimal factor = new BigDecimal(props.getProperty(key));
+                breedFactors.put(name, factor);
+            }
+        }
+        return breedFactors;
+    }
+
+    private TariffLoader() {}
+}

src/main/java/com/pfefferminzia/petinsurance/tariffs/TariffOption.java

@@ -0,0 +1,11 @@
+package com.pfefferminzia.petinsurance.tariffs;
+
+import java.math.BigDecimal;
+import java.time.LocalDate;
+
+public record TariffOption(String name, BigDecimal factor, LocalDate availableFrom) {
+    
+    public boolean isAvailableAt(LocalDate date) {
+        return !date.isBefore(availableFrom);
+    }
+}

src/main/resources/tariff.properties

@@ -0,0 +1,20 @@
+
+# Animal base insurance sums
+baseSum.DOG=2500.00
+baseSum.CAT=2000.00
+baseSum.SMALLANIMAL=1000.00
+
+# Tariffs: name=factor,availableFromDate
+tariffs.KOMPAKT=1.0,1970-01-01
+tariffs.OPTIMAL=1.2,1970-01-01
+tariffs.PREMIUM=1.4,2026-07-01
+
+# Age tariffs factor: age=factor
+age.2=0.20
+age.5=0.25
+age.7=0.28
+elderlyFactor=0.30
+
+# Dog breed premium factor
+breed.DACKEL=-0.1
+breed.BERNHARDINER=0.1