2 files changed, 109 insertions, 8 deletions

diff --git a/backend/src/main/java/org/luxons/sevenwonders/game/cards/Requirements.java b/backend/src/main/java/org/luxons/sevenwonders/game/cards/Requirements.java
index f6d7934c..942b64b7 100644
--- a/backend/src/main/java/org/luxons/sevenwonders/game/cards/Requirements.java
+++ b/backend/src/main/java/org/luxons/sevenwonders/game/cards/Requirements.java
@@ -31,15 +31,15 @@ public class Requirements {
     }
 
     boolean isAffordedBy(Board board) {
-        return board.getGold() >= gold && board.getProduction().contains(resources);
+        return hasRequiredGold(board) && producesRequiredResources(board);
     }
 
-    public boolean couldBeAffordedBy(Table table, int playerIndex) {
+    boolean couldBeAffordedBy(Table table, int playerIndex) {
         Board board = table.getBoard(playerIndex);
-        if (board.getGold() < gold) {
+        if (!hasRequiredGold(board)) {
             return false;
         }
-        if (board.getProduction().contains(resources)) {
+        if (producesRequiredResources(board)) {
             return true;
         }
         Resources leftToPay = resources.minus(board.getProduction().getFixedResources());
@@ -49,19 +49,38 @@ public class Requirements {
 
     public boolean isAffordedBy(Table table, int playerIndex, List<BoughtResources> boughtResources) {
         Board board = table.getBoard(playerIndex);
-        if (isAffordedBy(board)) {
+        if (!hasRequiredGold(board)) {
+            return false;
+        }
+        if (producesRequiredResources(board)) {
             return true;
         }
-        int totalPrice = board.getTradingRules().computeCost(boughtResources);
-        if (board.getGold() < totalPrice) {
+        if (!canAffordBoughtResources(board, boughtResources)) {
             return false;
         }
+        return producesRequiredResourcesWithHelp(board, boughtResources);
+    }
+
+    private boolean hasRequiredGold(Board board) {
+        return board.getGold() >= gold;
+    }
+
+    private boolean producesRequiredResources(Board board) {
+        return board.getProduction().contains(resources);
+    }
+
+    private boolean canAffordBoughtResources(Board board, List<BoughtResources> boughtResources) {
+        int resourcesPrice = board.getTradingRules().computeCost(boughtResources);
+        return board.getGold() - gold >= resourcesPrice;
+    }
+
+    private boolean producesRequiredResourcesWithHelp(Board board, List<BoughtResources> boughtResources) {
         Resources totalBoughtResources = getTotalResources(boughtResources);
         Resources remainingResources = this.resources.minus(totalBoughtResources);
         return board.getProduction().contains(remainingResources);
     }
 
-    private Resources getTotalResources(List<BoughtResources> boughtResources) {
+    private static Resources getTotalResources(List<BoughtResources> boughtResources) {
         return boughtResources.stream().map(BoughtResources::getResources).reduce(new Resources(), (r1, r2) -> {
             r1.addAll(r2);
             return r1;
diff --git a/backend/src/test/java/org/luxons/sevenwonders/game/cards/RequirementsTest.java b/backend/src/test/java/org/luxons/sevenwonders/game/cards/RequirementsTest.java
new file mode 100644
index 00000000..d851ae30
--- /dev/null
+++ b/backend/src/test/java/org/luxons/sevenwonders/game/cards/RequirementsTest.java
@@ -0,0 +1,82 @@
+package org.luxons.sevenwonders.game.cards;
+
+import java.util.Collections;
+
+import org.junit.experimental.theories.DataPoints;
+import org.junit.experimental.theories.Theories;
+import org.junit.experimental.theories.Theory;
+import org.junit.runner.RunWith;
+import org.luxons.sevenwonders.game.api.Table;
+import org.luxons.sevenwonders.game.boards.Board;
+import org.luxons.sevenwonders.game.resources.ResourceType;
+import org.luxons.sevenwonders.game.resources.Resources;
+import org.luxons.sevenwonders.game.test.TestUtils;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assume.assumeTrue;
+
+@RunWith(Theories.class)
+public class RequirementsTest {
+
+    @DataPoints
+    public static int[] goldAmounts() {
+        return new int[] {0, 1, 2, 5};
+    }
+
+    @DataPoints
+    public static ResourceType[] resourceTypes() {
+        return ResourceType.values();
+    }
+
+    @Theory
+    public void goldRequirement(int boardGold, int requiredGold) {
+        Requirements requirements = new Requirements();
+        requirements.setGold(requiredGold);
+
+        Board board = TestUtils.createBoard(ResourceType.CLAY, boardGold);
+        Table table = new Table(Collections.singletonList(board));
+
+        assertEquals(boardGold >= requiredGold, requirements.isAffordedBy(board));
+        assertEquals(boardGold >= requiredGold, requirements.isAffordedBy(table, 0, Collections.emptyList()));
+        assertEquals(boardGold >= requiredGold, requirements.couldBeAffordedBy(table, 0));
+    }
+
+    @Theory
+    public void resourceRequirement_initialResource(ResourceType initialResource, ResourceType requiredResource) {
+        Resources resources = TestUtils.createResources(requiredResource);
+        Requirements requirements = new Requirements();
+        requirements.setResources(resources);
+
+        Board board = TestUtils.createBoard(initialResource, 0);
+        Table table = new Table(Collections.singletonList(board));
+
+        assertEquals(initialResource == requiredResource, requirements.isAffordedBy(board));
+        assertEquals(initialResource == requiredResource, requirements.isAffordedBy(table, 0, Collections.emptyList()));
+
+        if (initialResource == requiredResource) {
+            assertTrue(requirements.couldBeAffordedBy(table, 0));
+        }
+    }
+
+    @Theory
+    public void resourceRequirement_ownProduction(ResourceType initialResource, ResourceType producedResource, ResourceType requiredResource) {
+        assumeTrue(initialResource != requiredResource);
+
+        Resources resources = TestUtils.createResources(requiredResource);
+        Requirements requirements = new Requirements();
+        requirements.setResources(resources);
+
+        Board board = TestUtils.createBoard(initialResource, 0);
+        board.getProduction().addFixedResource(producedResource, 1);
+        Table table = new Table(Collections.singletonList(board));
+
+        assertEquals(producedResource == requiredResource, requirements.isAffordedBy(board));
+        assertEquals(producedResource == requiredResource, requirements.isAffordedBy(table, 0, Collections.emptyList()));
+
+        if (producedResource == requiredResource) {
+            assertTrue(requirements.couldBeAffordedBy(table, 0));
+        }
+    }
+
+}
\ No newline at end of file