Add SimplifiedPredicate (#246)

Author: rcosta358

liquidjava-verifier/src/main/java/liquidjava/rj_language/SimplifiedPredicate.java

@@ -0,0 +1,108 @@
+package liquidjava.rj_language;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+import spoon.reflect.reference.CtTypeReference;
+
+/**
+ * Represents a predicate simplified from another predicate. Stores the original predicate and any variables that must
+ * be reintroduced as binders when relating the simplified predicate back to its origin.
+ * <p>
+ * For example, simplifying {@code x == 1 && y > x} with binders {@code x: int, y: int} may produce {@code y > 1}. The
+ * origin {@code x == 1 && y > x} and binder {@code x: int} are kept so we can relate the simplified predicate back to
+ * the original.
+ */
+public class SimplifiedPredicate extends Predicate {
+
+    private final Predicate origin;
+    private final List<Binder> binders;
+
+    public SimplifiedPredicate(Predicate simplified, Predicate origin) {
+        this(simplified, origin, List.of());
+    }
+
+    public SimplifiedPredicate(Predicate simplified, Predicate origin, List<Binder> binders) {
+        super(simplified.getExpression());
+        this.origin = origin;
+        this.binders = new ArrayList<>(binders);
+    }
+
+    public Predicate getSimplifiedPredicate() {
+        return new Predicate(getExpression());
+    }
+
+    public Predicate getOrigin() {
+        return origin;
+    }
+
+    public List<Binder> getBinders() {
+        return binders;
+    }
+
+    @Override
+    public SimplifiedPredicate clone() {
+        return new SimplifiedPredicate(new Predicate(getExpression().clone()), origin.clone(), binders);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(getExpression(), origin, binders);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        SimplifiedPredicate other = (SimplifiedPredicate) obj;
+        return getExpression().equals(other.getExpression()) && origin.equals(other.origin)
+                && binders.equals(other.binders);
+    }
+
+    /**
+     * Represents a variable that must be bound when relating the simplified predicate to its origin
+     */
+    public static class Binder {
+        private final String name;
+        private final String type;
+
+        public Binder(String name, String type) {
+            this.name = name;
+            this.type = type;
+        }
+
+        public Binder(String name, CtTypeReference<?> type) {
+            this(name, type.getQualifiedName());
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public String getType() {
+            return type;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(name, type);
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (this == obj)
+                return true;
+            if (obj == null)
+                return false;
+            if (getClass() != obj.getClass())
+                return false;
+            Binder other = (Binder) obj;
+            return name.equals(other.name) && type.equals(other.type);
+        }
+    }
+}