feat: discover default AI test toolchain

src/main/java/com/example/workutils/biz/aitest/config/AiTestSettingsService.java

@@ -19,6 +19,7 @@ import java.util.Properties;
 public class AiTestSettingsService {
 
     private final Path settingsFile;
+    private final ToolchainSettingsDetector detector;
 
     @Autowired
     public AiTestSettingsService(WorkUtilsProperties properties) {
@@ -29,20 +30,31 @@ public class AiTestSettingsService {
         this(paths.resolve("data", "ai-test"));
     }
 
+    AiTestSettingsService(ApplicationPaths paths, ToolchainSettingsDetector detector) {
+        this(paths.resolve("data", "ai-test"), detector);
+    }
+
     private AiTestSettingsService(Path aiTestDataDirectory) {
+        this(aiTestDataDirectory, ToolchainSettingsDetector.system());
+    }
+
+    AiTestSettingsService(Path aiTestDataDirectory, ToolchainSettingsDetector detector) {
         this.settingsFile = aiTestDataDirectory.resolve("settings.properties");
+        this.detector = detector;
     }
 
     public AiTestSettings load() throws IOException {
         if (Files.notExists(settingsFile)) {
-            return AiTestSettings.defaults();
+            AiTestSettings detected = detector.complete(AiTestSettings.defaults());
+            save(detected);
+            return detected;
         }
         Properties values = new Properties();
         try (InputStream input = Files.newInputStream(settingsFile)) {
             values.load(input);
         }
         AiTestSettings defaults = AiTestSettings.defaults();
-        return new AiTestSettings(
+        AiTestSettings loaded = new AiTestSettings(
                 Path.of(values.getProperty("jdk8.home", defaults.jdk8Home().toString())),
                 Path.of(values.getProperty("maven.home", defaults.mavenHome().toString())),
                 values.getProperty("codefree.command", defaults.codeFreeCommand()),
@@ -52,6 +64,11 @@ public class AiTestSettingsService {
                         Math.toIntExact(defaults.codeFreeTimeout().toSeconds()))),
                 Duration.ofSeconds(integer(values, "maven.timeout.seconds",
                         Math.toIntExact(defaults.mavenTimeout().toSeconds()))));
+        AiTestSettings completed = detector.complete(loaded);
+        if (!completed.equals(loaded)) {
+            save(completed);
+        }
+        return completed;
     }
 
     public void save(AiTestSettings settings) throws IOException {

src/main/java/com/example/workutils/biz/aitest/config/ToolchainSettingsDetector.java

@@ -0,0 +1,112 @@
+package com.example.workutils.biz.aitest.config;
+
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Map;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Predicate;
+import java.util.function.Supplier;
+
+public final class ToolchainSettingsDetector {
+    private static final Path WINDOWS_JDK8 = Path.of("C:/Program Files/Java/jdk-1.8");
+    private static final Path WINDOWS_MAVEN = Path.of("D:/bestpay-maven/apache-maven-3.8.6");
+
+    private final Map<String, String> environment;
+    private final Map<String, String> properties;
+    private final Supplier<String> mavenVersion;
+    private final Predicate<Path> directoryExists;
+    private final String osName;
+
+    public ToolchainSettingsDetector(Map<String, String> environment, Map<String, String> properties,
+                                     Supplier<String> mavenVersion, Predicate<Path> directoryExists,
+                                     String osName) {
+        this.environment = environment;
+        this.properties = properties;
+        this.mavenVersion = mavenVersion;
+        this.directoryExists = directoryExists;
+        this.osName = osName;
+    }
+
+    public static ToolchainSettingsDetector system() {
+        return new ToolchainSettingsDetector(System.getenv(),
+                Map.of("java.home", System.getProperty("java.home", "")),
+                ToolchainSettingsDetector::readMavenVersion, Files::isDirectory,
+                System.getProperty("os.name", ""));
+    }
+
+    public AiTestSettings complete(AiTestSettings saved) {
+        Path jdk = specified(saved.jdk8Home()) ? saved.jdk8Home() : detectJdk8();
+        Path maven = specified(saved.mavenHome()) ? saved.mavenHome() : detectMaven();
+        return new AiTestSettings(jdk, maven, saved.codeFreeCommand(), saved.coverageTarget(),
+                saved.maxRepairRounds(), saved.codeFreeTimeout(), saved.mavenTimeout());
+    }
+
+    private Path detectJdk8() {
+        Path environmentHome = path(environment.get("JAVA_HOME"));
+        if (usable(environmentHome)) return normalizeJdk(environmentHome);
+        Path runtimeHome = normalizeJdk(path(properties.get("java.home")));
+        if (usable(runtimeHome)) return runtimeHome;
+        return windows() && usable(WINDOWS_JDK8) ? WINDOWS_JDK8 : Path.of("");
+    }
+
+    private Path detectMaven() {
+        for (String key : new String[]{"MAVEN_HOME", "M2_HOME"}) {
+            Path candidate = path(environment.get(key));
+            if (usable(candidate)) return candidate;
+        }
+        Path parsed = parseMavenHome(mavenVersion.get());
+        if (usable(parsed)) return parsed;
+        return windows() && usable(WINDOWS_MAVEN) ? WINDOWS_MAVEN : Path.of("");
+    }
+
+    static Path parseMavenHome(String output) {
+        if (output != null) {
+            for (String line : output.split("\\R")) {
+                if (line.regionMatches(true, 0, "Maven home:", 0, "Maven home:".length())) {
+                    return path(line.substring("Maven home:".length()).trim());
+                }
+            }
+        }
+        return Path.of("");
+    }
+
+    private Path normalizeJdk(Path value) {
+        if (value != null && value.getFileName() != null
+                && "jre".equalsIgnoreCase(value.getFileName().toString())) {
+            return value.getParent();
+        }
+        return value;
+    }
+
+    private boolean usable(Path path) {
+        return path != null && !path.toString().isBlank() && directoryExists.test(path);
+    }
+
+    private static boolean specified(Path path) {
+        return path != null && !path.toString().isBlank();
+    }
+
+    private boolean windows() {
+        return osName.toLowerCase().contains("win");
+    }
+
+    private static Path path(String value) {
+        return value == null || value.isBlank() ? Path.of("") : Path.of(value.trim());
+    }
+
+    private static String readMavenVersion() {
+        try {
+            Process process = new ProcessBuilder("mvn", "-version").redirectErrorStream(true).start();
+            if (!process.waitFor(5, TimeUnit.SECONDS)) {
+                process.destroyForcibly();
+                return "";
+            }
+            return new String(process.getInputStream().readAllBytes(), Charset.defaultCharset());
+        } catch (IOException | InterruptedException ignored) {
+            if (ignored instanceof InterruptedException) Thread.currentThread().interrupt();
+            return "";
+        }
+    }
+}

src/test/java/com/example/workutils/biz/aitest/config/AiTestSettingsServiceTest.java

@@ -6,6 +6,7 @@ import org.junit.jupiter.api.io.TempDir;
 
 import java.nio.file.Path;
 import java.time.Duration;
+import java.util.Map;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
@@ -26,11 +27,18 @@ class AiTestSettingsServiceTest {
 
     @Test
     void returnsSafeDefaultsWhenNoSettingsExist(@TempDir Path home) throws Exception {
-        AiTestSettings settings = new AiTestSettingsService(ApplicationPaths.of(home)).load();
+        ToolchainSettingsDetector detector = new ToolchainSettingsDetector(
+                Map.of("JAVA_HOME", "C:/jdk8", "MAVEN_HOME", "C:/maven"), Map.of(),
+                () -> "", ignored -> true, "Windows 11");
+        AiTestSettingsService service = new AiTestSettingsService(ApplicationPaths.of(home), detector);
+
+        AiTestSettings settings = service.load();
 
         assertEquals(85, settings.coverageTarget());
         assertEquals(3, settings.maxRepairRounds());
         assertEquals("codefree", settings.codeFreeCommand());
-        assertTrue(settings.jdk8Home().toString().isEmpty());
+        assertEquals(Path.of("C:/jdk8"), settings.jdk8Home());
+        assertEquals(Path.of("C:/maven"), settings.mavenHome());
+        assertTrue(java.nio.file.Files.exists(service.settingsFile()));
     }
 }

src/test/java/com/example/workutils/biz/aitest/config/ToolchainSettingsDetectorTest.java

@@ -0,0 +1,38 @@
+package com.example.workutils.biz.aitest.config;
+
+import org.junit.jupiter.api.Test;
+
+import java.nio.file.Path;
+import java.util.Map;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+class ToolchainSettingsDetectorTest {
+
+    @Test
+    void discoversJdkRootFromJavaHomeJreAndParsesMavenHome() {
+        ToolchainSettingsDetector detector = new ToolchainSettingsDetector(Map.of(),
+                Map.of("java.home", "C:/Program Files/Java/jdk-1.8/jre"),
+                () -> "Apache Maven 3.8.6\nMaven home: D:/bestpay-maven/apache-maven-3.8.6",
+                ignored -> true, "Windows 11");
+
+        AiTestSettings result = detector.complete(AiTestSettings.defaults());
+
+        assertEquals(Path.of("C:/Program Files/Java/jdk-1.8"), result.jdk8Home());
+        assertEquals(Path.of("D:/bestpay-maven/apache-maven-3.8.6"), result.mavenHome());
+    }
+
+    @Test
+    void keepsUsableSavedPathsAheadOfDiscoveredValues() {
+        ToolchainSettingsDetector detector = new ToolchainSettingsDetector(
+                Map.of("JAVA_HOME", "C:/auto-jdk", "MAVEN_HOME", "C:/auto-maven"),
+                Map.of(), () -> "", ignored -> true, "Windows 11");
+        AiTestSettings saved = new AiTestSettings(Path.of("C:/saved-jdk"), Path.of("C:/saved-maven"),
+                "codefree", 85, 3, java.time.Duration.ofMinutes(5), java.time.Duration.ofMinutes(15));
+
+        AiTestSettings result = detector.complete(saved);
+
+        assertEquals(saved.jdk8Home(), result.jdk8Home());
+        assertEquals(saved.mavenHome(), result.mavenHome());
+    }
+}