From 89c87effe9f3c1d8f6f497cc925e300888681665 Mon Sep 17 00:00:00 2001
From: Sebastian Toepfer <61313468+sebastian-toepfer@users.noreply.github.com>
Date: Mon, 9 Oct 2023 19:38:19 +0200
Subject: [PATCH] add annotation for patternProerties keyword

---
 .../PatternPropertiesKeywordType.java         | 17 ++++++++++-
 .../PatternPropertiesKeywordTypeTest.java     | 28 +++++++++++++++++++
 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/core/src/main/java/io/github/sebastiantoepfer/jsonschema/core/vocab/applicator/PatternPropertiesKeywordType.java b/core/src/main/java/io/github/sebastiantoepfer/jsonschema/core/vocab/applicator/PatternPropertiesKeywordType.java
index 642707b3..d68f27f7 100644
--- a/core/src/main/java/io/github/sebastiantoepfer/jsonschema/core/vocab/applicator/PatternPropertiesKeywordType.java
+++ b/core/src/main/java/io/github/sebastiantoepfer/jsonschema/core/vocab/applicator/PatternPropertiesKeywordType.java
@@ -23,12 +23,16 @@
  */
 package io.github.sebastiantoepfer.jsonschema.core.vocab.applicator;
 
+import static jakarta.json.stream.JsonCollectors.toJsonArray;
+
 import io.github.sebastiantoepfer.jsonschema.InstanceType;
 import io.github.sebastiantoepfer.jsonschema.JsonSchema;
 import io.github.sebastiantoepfer.jsonschema.JsonSchemas;
+import io.github.sebastiantoepfer.jsonschema.keyword.Annotation;
 import io.github.sebastiantoepfer.jsonschema.keyword.Applicator;
 import io.github.sebastiantoepfer.jsonschema.keyword.Keyword;
 import io.github.sebastiantoepfer.jsonschema.keyword.KeywordType;
+import jakarta.json.Json;
 import jakarta.json.JsonObject;
 import jakarta.json.JsonValue;
 import java.util.Collection;
@@ -50,7 +54,7 @@ public Keyword createKeyword(final JsonSchema schema, final JsonValue value) {
         return new PatternPropertiesKeyword(value.asJsonObject());
     }
 
-    private class PatternPropertiesKeyword implements Applicator {
+    private class PatternPropertiesKeyword implements Applicator, Annotation {
 
         private final Map<Pattern, JsonValue> properties;
 
@@ -93,5 +97,16 @@ private boolean propertyMatches(final Map.Entry<String, JsonValue> property) {
                 .map(schema -> schema.validator().validate(property.getValue()).isEmpty())
                 .orElse(true);
         }
+
+        @Override
+        public JsonValue valueFor(final JsonValue value) {
+            return value
+                .asJsonObject()
+                .keySet()
+                .stream()
+                .filter(name -> properties.keySet().stream().anyMatch(p -> p.matcher(name).find()))
+                .map(Json::createValue)
+                .collect(toJsonArray());
+        }
     }
 }
diff --git a/core/src/test/java/io/github/sebastiantoepfer/jsonschema/core/vocab/applicator/PatternPropertiesKeywordTypeTest.java b/core/src/test/java/io/github/sebastiantoepfer/jsonschema/core/vocab/applicator/PatternPropertiesKeywordTypeTest.java
index f9fcadd1..aa6c7f8e 100644
--- a/core/src/test/java/io/github/sebastiantoepfer/jsonschema/core/vocab/applicator/PatternPropertiesKeywordTypeTest.java
+++ b/core/src/test/java/io/github/sebastiantoepfer/jsonschema/core/vocab/applicator/PatternPropertiesKeywordTypeTest.java
@@ -30,7 +30,9 @@
 import io.github.sebastiantoepfer.jsonschema.core.DefaultJsonSchemaFactory;
 import io.github.sebastiantoepfer.jsonschema.keyword.Keyword;
 import jakarta.json.Json;
+import jakarta.json.JsonString;
 import jakarta.json.JsonValue;
+import java.math.BigDecimal;
 import org.junit.jupiter.api.Test;
 
 class PatternPropertiesKeywordTypeTest {
@@ -117,4 +119,30 @@ void should_be_valid_if_properties_not_covered() {
             is(true)
         );
     }
+
+    @Test
+    void should_return_the_matching_property_names() {
+        assertThat(
+            new PatternPropertiesKeywordType()
+                .createKeyword(
+                    new DefaultJsonSchemaFactory().create(JsonValue.TRUE),
+                    Json.createObjectBuilder().add("f.o", JsonValue.TRUE).build()
+                )
+                .asAnnotation()
+                .valueFor(
+                    Json
+                        .createObjectBuilder()
+                        .add("foo", BigDecimal.ONE)
+                        .add("test", BigDecimal.ONE)
+                        .add("fao", 1)
+                        .build()
+                )
+                .asJsonArray()
+                .stream()
+                .map(JsonString.class::cast)
+                .map(JsonString::getString)
+                .toList(),
+            containsInAnyOrder("foo", "fao")
+        );
+    }
 }