1 files changed, 83 insertions, 0 deletions

diff --git a/subprojects/logic/src/main/java/tools/refinery/logic/term/uppercardinality/FiniteUpperCardinality.java b/subprojects/logic/src/main/java/tools/refinery/logic/term/uppercardinality/FiniteUpperCardinality.java
new file mode 100644
index 00000000..478d456b
--- /dev/null
+++ b/subprojects/logic/src/main/java/tools/refinery/logic/term/uppercardinality/FiniteUpperCardinality.java
@@ -0,0 +1,83 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.logic.term.uppercardinality;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.IntBinaryOperator;
+
+public record FiniteUpperCardinality(int finiteUpperBound) implements UpperCardinality {
+        public FiniteUpperCardinality {
+                if (finiteUpperBound < 0) {
+                        throw new IllegalArgumentException("finiteUpperBound must not be negative");
+                }
+        }
+
+        @Override
+        public UpperCardinality add(UpperCardinality other) {
+                return lift(other, Integer::sum);
+        }
+
+        @Override
+        @Nullable
+        public UpperCardinality take(int count) {
+                if (finiteUpperBound < count) {
+                        return null;
+                }
+                return new FiniteUpperCardinality(finiteUpperBound - count);
+        }
+
+        @Override
+        public UpperCardinality multiply(UpperCardinality other) {
+                return lift(other, (a, b) -> a * b);
+        }
+
+        @Override
+        public int compareTo(@NotNull UpperCardinality upperCardinality) {
+                if (upperCardinality instanceof FiniteUpperCardinality finiteUpperCardinality) {
+                        return compareToInt(finiteUpperCardinality.finiteUpperBound);
+                }
+                if (upperCardinality instanceof UnboundedUpperCardinality) {
+                        return -1;
+                }
+                throw new IllegalArgumentException("Unknown UpperCardinality: " + upperCardinality);
+        }
+
+        @Override
+        public int compareToInt(int value) {
+                return Integer.compare(finiteUpperBound, value);
+        }
+
+        @Override
+        public String toString() {
+                return Integer.toString(finiteUpperBound);
+        }
+
+        private UpperCardinality lift(@NotNull UpperCardinality other, IntBinaryOperator operator) {
+                if (other instanceof FiniteUpperCardinality finiteUpperCardinality) {
+                        return UpperCardinalities.atMost(operator.applyAsInt(finiteUpperBound,
+                                        finiteUpperCardinality.finiteUpperBound));
+                }
+                if (other instanceof UnboundedUpperCardinality) {
+                        return UpperCardinalities.UNBOUNDED;
+                }
+                throw new IllegalArgumentException("Unknown UpperCardinality: " + other);
+        }
+
+        @Override
+        public boolean equals(Object o) {
+                if (this == o) return true;
+                if (o == null || getClass() != o.getClass()) return false;
+                FiniteUpperCardinality that = (FiniteUpperCardinality) o;
+                return finiteUpperBound == that.finiteUpperBound;
+        }
+
+        @Override
+        public int hashCode() {
+                return finiteUpperBound;
+        }
+}