Initial commit

src/main/java/commanderailab/schema/JsonExporter.java

@@ -0,0 +1,74 @@
+package commanderailab.schema;
+
+import com.google.gson.Gson;
+import com.google.gson.GsonBuilder;
+
+import java.io.*;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.*;
+
+/**
+ * JsonExporter — Serializes BatchResult to JSON files.
+ *
+ * Output conforms to batch-result-schema.json.
+ */
+public class JsonExporter {
+
+    private static final Gson GSON = new GsonBuilder()
+            .setPrettyPrinting()
+            .serializeNulls()
+            .disableHtmlEscaping()
+            .create();
+
+    /**
+     * Serialize a BatchResult to a JSON string.
+     */
+    public static String toJson(BatchResult result) {
+        return GSON.toJson(result);
+    }
+
+    /**
+     * Write a BatchResult to a JSON file.
+     *
+     * @param result   The batch result to export
+     * @param filePath Output file path (e.g., "results/batch-20260306-001.json")
+     * @throws IOException if file cannot be written
+     */
+    public static void writeToFile(BatchResult result, String filePath) throws IOException {
+        Path path = Paths.get(filePath);
+
+        // Ensure parent directories exist
+        if (path.getParent() != null) {
+            Files.createDirectories(path.getParent());
+        }
+
+        String json = toJson(result);
+        Files.writeString(path, json, StandardCharsets.UTF_8);
+    }
+
+    /**
+     * Read a BatchResult from a JSON file.
+     */
+    public static BatchResult readFromFile(String filePath) throws IOException {
+        String json = Files.readString(Paths.get(filePath), StandardCharsets.UTF_8);
+        return GSON.fromJson(json, BatchResult.class);
+    }
+
+    /**
+     * Validate that a JSON string contains all required top-level keys.
+     * (Lightweight validation — full JSON Schema validation would need a library.)
+     */
+    public static boolean validateBasicStructure(String json) {
+        try {
+            BatchResult result = GSON.fromJson(json, BatchResult.class);
+            return result.metadata != null
+                    && result.decks != null && result.decks.size() == 3
+                    && result.games != null
+                    && result.summary != null
+                    && result.metadata.schemaVersion.equals("1.0.0")
+                    && result.metadata.podSize == 3;
+        } catch (Exception e) {
+            return false;
+        }
+    }
+}