package jmri.server.json.util;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;

import java.io.*;
import java.util.Locale;

import jmri.InstanceManager;
import jmri.JmriException;
import jmri.server.json.JsonServerPreferences;
import jmri.jmrit.display.Editor;
import jmri.jmrit.display.controlPanelEditor.ControlPanelEditor;
import jmri.jmrit.display.layoutEditor.LayoutEditor;
import jmri.jmrit.display.panelEditor.PanelEditor;
import jmri.jmrit.display.switchboardEditor.SwitchboardEditor;
import jmri.profile.NullProfile;
import jmri.server.json.JSON;
import jmri.server.json.JsonException;
import jmri.server.json.JsonMockConnection;
import jmri.server.json.JsonRequest;
import jmri.util.JUnitUtil;
import jmri.util.junit.annotations.DisabledIfHeadless;
import jmri.web.server.WebServerPreferences;

import org.junit.jupiter.api.*;
import org.junit.jupiter.api.io.TempDir;

import static org.junit.jupiter.api.Assertions.*;

/**
 * @author Randall Wood
 */
public class JsonUtilSocketServiceTest {

    private final Locale locale = Locale.ENGLISH;

    @BeforeEach
    public void setUp(@TempDir File folder) throws IOException {
        JUnitUtil.setUp();
        // list open windows when running tests
        JUnitUtil.resetWindows(true, false);
        JUnitUtil.resetNodeIdentity();
        JUnitUtil.resetProfileManager(
                new NullProfile("JsonUtilHttpServiceTest", "12345678", folder));
        JUnitUtil.initConfigureManager();
        // Initialize mock PermissionManager for session authentication tests
        InstanceManager.store(new MockPermissionManager(), jmri.PermissionManager.class);
    }

    @AfterEach
    public void tearDown() {
        JUnitUtil.resetWindows(false, false);
        JUnitUtil.deregisterBlockManagerShutdownTask();
        JUnitUtil.tearDown();
    }

    /**
     * Test of onMessage method, of class JsonUtilSocketService. Tests only
     * responses that are expected to be consistent between a
     *
     * @throws java.io.IOException if an unexpected exception occurs.
     * @throws jmri.JmriException if an unexpected exception occurs.
     * @throws jmri.server.json.JsonException if an unexpected exception occurs.
     */
    @Test
    public void testOnMessage() throws IOException, JmriException, JsonException {
        JsonNode message;
        InstanceManager.getDefault(JsonServerPreferences.class).setValidateServerMessages(true);
        JsonMockConnection connection = new JsonMockConnection((DataOutputStream) null);
        JsonNode empty = connection.getObjectMapper().createObjectNode();
        JsonUtilSocketService instance = new JsonUtilSocketService(connection);
        // JSON.LOCALE
        instance.onMessage(JSON.LOCALE, empty, new JsonRequest(locale, JSON.V5, JSON.POST, 42));
        assertNull(connection.getMessage()); // assert no reply
        // JSON.PING
        instance.onMessage(JSON.PING, empty, new JsonRequest(locale, JSON.V5, JSON.POST, 42));
        message = connection.getMessage();
        assertNotNull( message, "message is not null");
        JsonNode result = message.path(JSON.TYPE);
        assertNotNull(result);
        assertTrue(JsonNode.class.isInstance(result));
        assertEquals(JSON.PONG, result.asText());
        assertTrue(message.path(JSON.DATA).isMissingNode());
        // JSON.RAILROAD
        WebServerPreferences wsp = InstanceManager.getDefault(WebServerPreferences.class);
        instance.onMessage(JSON.RAILROAD, empty, new JsonRequest(locale, JSON.V5, JSON.GET, 42));
        message = connection.getMessage();
        assertNotNull( message, "message is not null");
        result = message.path(JSON.DATA);
        assertNotNull(result);
        assertEquals(JSON.RAILROAD, message.path(JSON.TYPE).asText());
        assertEquals( wsp.getRailroadName(), result.path(JSON.NAME).asText(), "Railroad name matches");
        wsp.setRailroadName("test railroad");
        message = connection.getMessage();
        assertNotNull( message, "message is not null");
        result = message.path(JSON.DATA);
        assertNotNull(result);
        assertEquals(JSON.RAILROAD, message.path(JSON.TYPE).asText());
        assertEquals( wsp.getRailroadName(), result.path(JSON.NAME).asText(), "Railroad name matches");
        // JSON.NETWORK_SERVICE (should return 404 because not running the
        // requested service)
        message = connection.getObjectMapper().createObjectNode().put(JSON.NAME, JSON.ZEROCONF_SERVICE_TYPE);
        final var finalMessage = message;
        JsonException ex = assertThrows(JsonException.class,
            () -> instance.onMessage(JSON.NETWORK_SERVICE, finalMessage,
                new JsonRequest(locale, JSON.V5, JSON.GET, 42)));
        assertEquals( 404, ex.getCode(), "HTTP Not Found");
        assertEquals( "Unable to access networkService _jmri-json._tcp.local..", ex.getMessage(),
            "Error Message");

        // JSON.GOODBYE
        instance.onMessage(JSON.GOODBYE, empty, new JsonRequest(locale, JSON.V5, JSON.POST, 42));
        message = connection.getMessage();
        assertNotNull( message, "message is not null");
        result = message.path(JSON.TYPE);
        assertNotNull(result);
        assertTrue(JsonNode.class.isInstance(result));
        assertEquals(JSON.GOODBYE, result.asText());
        assertTrue(message.path(JSON.DATA).isMissingNode());
    }

    /**
     * Test of onMessage method, of class JsonUtilSocketService.
     * Tests PANEL JSON type if not running headless.
     *
     * @throws java.io.IOException if an unexpected exception occurs.
     * @throws jmri.JmriException if an unexpected exception occurs.
     * @throws jmri.server.json.JsonException if an unexpected exception occurs.
     */
    @Test
    @DisabledIfHeadless
    public void testOnMessagePanels() throws IOException, JmriException, JsonException {

        Editor editor = new SwitchboardEditor("json test switchboard");
        JsonMockConnection connection = new JsonMockConnection((DataOutputStream) null);
        JsonNode empty = connection.getObjectMapper().createObjectNode();
        JsonUtilSocketService instance = new JsonUtilSocketService(connection);
        JsonException ex = assertThrows(JsonException.class,
            () -> instance.onMessage(JSON.PANELS, empty,
                new JsonRequest(locale, JSON.V5, JSON.GET, 42)));
        assertEquals( 404, ex.getCode(), "HTTP Not Found");
        assertEquals( "Unable to access panel .", ex.getMessage(), "Error Message");

        JsonNode data =
                connection.getObjectMapper().createObjectNode().put(JSON.NAME, "Switchboard/json%20test%20switchboard");
        instance.onMessage(JSON.PANEL, data, new JsonRequest(locale, JSON.V5, JSON.GET, 42));

        JUnitUtil.dispose(editor.getTargetFrame());
        JUnitUtil.dispose(editor);
    }

    /**
     * Test of onList method, of class JsonUtilSocketService. Does not test
     * CONFIG_PROFILE JSON type, see {@link #testOnListConfigProfile()} for
     * that. Does not test PANEL JSON type, see {@link #testOnListPanels()} for
     * that.
     *
     * @throws java.io.IOException if an unexpected exception occurs.
     * @throws jmri.JmriException if an unexpected exception occurs.
     * @throws jmri.server.json.JsonException if an unexpected exception occurs.
     */
    @Test
    public void testOnList() throws IOException, JmriException, JsonException {
        ObjectMapper mapper = new ObjectMapper();
        JsonMockConnection connection = new JsonMockConnection((DataOutputStream) null);
        JsonNode empty = connection.getObjectMapper().createObjectNode();
        JsonUtilSocketService instance = new JsonUtilSocketService(connection);
        JsonUtilHttpService helper = new JsonUtilHttpService(mapper);
        InstanceManager.getDefault(JsonServerPreferences.class).setHeartbeatInterval(10);
        instance.onList(JSON.METADATA, empty, new JsonRequest(locale, JSON.V5, JSON.GET, 42));
        assertEquals(helper.getMetadata(new JsonRequest(locale, JSON.V5, JSON.GET, 42)), connection.getMessage());
        instance.onList(JSON.NETWORK_SERVICES, empty, new JsonRequest(locale, JSON.V5, JSON.GET, 42));
        assertEquals(helper.getNetworkServices(new JsonRequest(locale, JSON.V5, JSON.GET, 42)), connection.getMessage());
        instance.onList(JSON.SYSTEM_CONNECTIONS, empty, new JsonRequest(locale, JSON.V5, JSON.GET, 42));
        assertEquals(helper.getSystemConnections(new JsonRequest(locale, JSON.V5, JSON.GET, 42)), connection.getMessage());
    }

    /**
     * Test of onList method for CONFIG_PROFILE JSON type, of class
     * JsonUtilSocketService.
     *
     * @throws java.io.IOException if an unexpected exception occurs.
     * @throws jmri.JmriException if an unexpected exception occurs.
     * @throws jmri.server.json.JsonException if an unexpected exception occurs.
     */
    @Test
    public void testOnListConfigProfile() throws IOException, JmriException, JsonException {
        ObjectMapper mapper = new ObjectMapper();
        JsonMockConnection connection = new JsonMockConnection((DataOutputStream) null);
        JsonNode empty = connection.getObjectMapper().createObjectNode();
        JsonUtilSocketService instance = new JsonUtilSocketService(connection);
        JsonUtilHttpService helper = new JsonUtilHttpService(mapper);
        InstanceManager.getDefault(JsonServerPreferences.class).setHeartbeatInterval(10);
        instance.onList(JSON.CONFIG_PROFILES, empty, new JsonRequest(locale, JSON.V5, JSON.GET, 42));
        assertEquals(helper.getConfigProfiles(new JsonRequest(locale, JSON.V5, JSON.GET, 42)), connection.getMessage());
    }

    /**
     * Test of onList method, of class JsonUtilSocketService. Tests PANEL JSON
     * type if not running headless.
     *
     * @throws java.io.IOException if an unexpected exception occurs.
     * @throws jmri.JmriException if an unexpected exception occurs.
     * @throws jmri.server.json.JsonException if an unexpected exception occurs.
     */
    @Test
    @DisabledIfHeadless
    public void testOnListPanels() throws IOException, JmriException, JsonException {

        Editor switchboard = new SwitchboardEditor("json test switchboard");
        Editor controlPanel = new ControlPanelEditor("json test control panel");
        Editor layoutPanel = new LayoutEditor("json test layout panel");
        Editor panel = new PanelEditor("json test panel");
        Editor disabled = new PanelEditor("disabled json test panel");
        disabled.setAllowInFrameServlet(false);
        // 5 editors should return array of 4 since one is barred
        JsonMockConnection connection = new JsonMockConnection((DataOutputStream) null);
        JsonNode empty = connection.getObjectMapper().createObjectNode();
        JsonUtilSocketService instance = new JsonUtilSocketService(connection);
        instance.onList(JSON.PANELS, empty, new JsonRequest(locale, JSON.V5, JSON.GET, 42));
        JsonNode message = connection.getMessage();
        assertNotNull( message, "Message is not null");
        assertTrue( message.isArray(), "Message is array");
        assertEquals( 4, message.size(),
            () -> "Array has four elements, what panel was left in place that triggered this? "
                + message.toString());
        JUnitUtil.dispose(switchboard.getTargetFrame());
        JUnitUtil.dispose(switchboard);
        JUnitUtil.dispose(controlPanel.getTargetFrame());
        JUnitUtil.dispose(controlPanel);
        JUnitUtil.dispose(layoutPanel.getTargetFrame());
        JUnitUtil.dispose(layoutPanel);
        JUnitUtil.dispose(panel.getTargetFrame());
        JUnitUtil.dispose(panel);
    }

    @Test
    public void testRRNameListener() throws IOException, JmriException, JsonException {
        JsonMockConnection connection = new JsonMockConnection((DataOutputStream) null);
        JsonNode empty = connection.getObjectMapper().createObjectNode();
        TestJsonUtilHttpService httpService = new TestJsonUtilHttpService(connection.getObjectMapper());
        JsonUtilSocketService instance = new JsonUtilSocketService(connection, httpService);
        WebServerPreferences preferences = InstanceManager.getDefault(WebServerPreferences.class);
        assertEquals( 0, preferences.getPropertyChangeListeners().length, "No preferences listener");
        instance.onMessage(JSON.RAILROAD, empty, new JsonRequest(locale, JSON.V5, JSON.GET, 42));
        JsonNode message = connection.getMessage();
        assertNotNull( message, "Message is not null");
        assertEquals( preferences.getRailroadName(),
            message.path(JSON.DATA).path(JSON.NAME).asText(),
            "Message has RR Name");
        assertEquals( 1, preferences.getPropertyChangeListeners().length, "There is a preferences listener");
        preferences.setRailroadName("New Name");
        message = connection.getMessage();
        assertNotNull( message, "Message is not null");
        assertEquals( preferences.getRailroadName(),
            message.path(JSON.DATA).path(JSON.NAME).asText(),
            "Message has RR Name");
        // force JsonException
        httpService.setThrowException(true);
        preferences.setRailroadName("Another New Name");
        message = connection.getMessage();
        assertNotNull( message, "Message is not null");
        assertEquals( JsonException.ERROR, message.path(JSON.TYPE).asText(), "Message is error");
        assertEquals( 499, message.path(JSON.DATA).path(JsonException.CODE).asInt(),
            "Error code is 499");
        // force IOException
        assertEquals( 1, preferences.getPropertyChangeListeners().length, "There is a preferences listener");
        connection.setThrowIOException(true);
        preferences.setRailroadName("Yet Another New Name");
        assertEquals( 0, preferences.getPropertyChangeListeners().length,
            "There is no longer a preferences listener");
    }

    /**
     * Test of onClose method, of class JsonUtilSocketService. This tests that
     * listeners are removed after a message triggering the addition of a
     * listener is sent.
     *
     * @throws JsonException if an exception unexpected in the context of these
     *                       tests occurs
     * @throws JmriException if an exception unexpected in the context of these
     *                       tests occurs
     * @throws IOException   if an exception unexpected in the context of these
     *                       tests occurs
     */
    @Test
    public void testOnClose() throws IOException, JmriException, JsonException {
        WebServerPreferences wsp = InstanceManager.getDefault(WebServerPreferences.class);
        assertEquals( 0, wsp.getPropertyChangeListeners().length, "listeners");
        JsonUtilSocketService instance = new JsonUtilSocketService(new JsonMockConnection((DataOutputStream) null));
        instance.onMessage(JSON.RAILROAD, instance.getConnection().getObjectMapper().nullNode(),
                new JsonRequest(locale, JSON.V5, JSON.GET, 0));
        assertEquals( 1, wsp.getPropertyChangeListeners().length, "listeners");
        instance.onClose();
        assertEquals( 0, wsp.getPropertyChangeListeners().length, "listeners");
    }

    /**
     * Test SESSION_LOGIN message handling via onMessage.
     *
     * @throws IOException if test fails unexpectedly
     * @throws JmriException if test fails unexpectedly
     * @throws JsonException expected for invalid credentials in test
     */
    @Test
    public void testSessionLoginMessage() throws IOException, JmriException, JsonException {
        JsonMockConnection connection = new JsonMockConnection((DataOutputStream) null);
        JsonUtilSocketService instance = new JsonUtilSocketService(connection);
        ObjectNode loginData = connection.getObjectMapper().createObjectNode();
        loginData.put("username", "testuser");
        loginData.put("password", "testpass");

        try {
            instance.onMessage(JSON.SESSION_LOGIN, loginData,
                new JsonRequest(locale, JSON.V5, JSON.POST, 42));
            JsonNode message = connection.getMessage();
            assertNotNull(message, "Should receive a message");
            // In test environment without configured users, should get error
        } catch (JsonException ex) {
            // Expected - no valid users configured in test
            assertTrue(ex.getCode() == 401 || ex.getCode() == 403,
                "Expected unauthorized or forbidden error");
        }
    }

    /**
     * Test SESSION_LOGOUT message handling via onMessage.
     *
     * @throws IOException if test fails unexpectedly
     * @throws JmriException if test fails unexpectedly
     * @throws JsonException if test fails unexpectedly
     */
    @Test
    public void testSessionLogoutMessage() throws IOException, JmriException, JsonException {
        JsonMockConnection connection = new JsonMockConnection((DataOutputStream) null);
        JsonUtilSocketService instance = new JsonUtilSocketService(connection);
        ObjectNode logoutData = connection.getObjectMapper().createObjectNode();
        logoutData.put("token", "test-session-token");
        logoutData.put(JSON.USERNAME, "testuser");

        instance.onMessage(JSON.SESSION_LOGOUT, logoutData,
            new JsonRequest(locale, JSON.V5, JSON.POST, 42));
        JsonNode message = connection.getMessage();
        assertNotNull(message, "Should receive logout confirmation");
        assertEquals(JSON.SESSION_LOGOUT, message.path(JSON.TYPE).asText(),
            "Message type should be sessionLogout");
        assertEquals("test-session-token", message.path(JSON.DATA).path("authenticationToken").asText(),
            "Should return the token");
    }

    /**
     * Mock PermissionManager for testing session authentication.
     */
    private static class MockPermissionManager implements jmri.PermissionManager {
        @Override
        public boolean remoteLogin(StringBuilder sessionId, java.util.Locale locale,
                                  String username, String password) {
            // Reject guest users
            if ("guest".equals(username)) {
                return false;
            }
            // Accept any non-guest user for testing
            sessionId.append("test-session-").append(username);
            return true;
        }

        @Override
        public void remoteLogout(String sessionId) {
            // No-op for testing
        }

        @Override
        public boolean isAGuestUser(String username) {
            return "guest".equals(username);
        }

        @Override
        public boolean isAGuestUser(jmri.User user) {
            return user != null && isAGuestUser(user.getUserName());
        }

        // Stub implementations for other required methods
        @Override
        public jmri.Role addRole(String name) { return null; }
        @Override
        public void removeRole(String name) {}
        @Override
        public jmri.User addUser(String username, String password) { return null; }
        @Override
        public void removeUser(String username) {}
        @Override
        public void changePassword(String newPassword, String oldPassword) {}
        @Override
        public boolean login(String username, String password) { return false; }
        @Override
        public void logout() {}
        @Override
        public String getCurrentUserName() { return null; }
        @Override
        public boolean isCurrentUser(String username) { return false; }
        @Override
        public boolean isCurrentUser(jmri.User user) { return false; }
        @Override
        public boolean isCurrentUserPermittedToChangePassword() { return false; }
        @Override
        public boolean isLoggedIn() { return false; }
        @Override
        public boolean isRemotelyLoggedIn(String sessionId) { return false; }
        @Override
        public void addLoginListener(LoginListener listener) {}
        @Override
        public boolean isEnabled() { return true; }
        @Override
        public void setEnabled(boolean enabled) {}
        @Override
        public boolean isAllowEmptyPasswords() { return false; }
        @Override
        public void setAllowEmptyPasswords(boolean value) {}
        @Override
        public boolean hasAtLeastPermission(jmri.Permission permission, jmri.PermissionValue minValue) { return true; }
        @Override
        public boolean hasAtLeastRemotePermission(String sessionId, jmri.Permission permission, jmri.PermissionValue minValue) { return true; }
        @Override
        public boolean ensureAtLeastPermission(jmri.Permission permission, jmri.PermissionValue minValue) { return true; }
        @Override
        public void registerOwner(jmri.PermissionOwner owner) {}
        @Override
        public void registerPermission(jmri.Permission permission) {}
        @Override
        public void storePermissionSettings() {}
    }

    private static class TestJsonUtilHttpService extends JsonUtilHttpService {

        private boolean throwException = false;

        TestJsonUtilHttpService(ObjectMapper mapper) {
            super(mapper);
        }

        @Override
        public JsonNode doGet(String type, String name, JsonNode data, JsonRequest request) throws JsonException {
            if (throwException) {
                throwException = false;
                throw new JsonException(499, "Mock Exception", request.id);
            }
            return super.doGet(type, name, data, request);
        }

        void setThrowException(boolean throwException) {
            this.throwException = throwException;
        }

    }

    // private static final org.slf4j.Logger log = org.slf4j.LoggerFactory.getLogger(JsonUtilSocketServiceTest.class);
}