package com.example.service;

import java.util.*;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import javax.sql.DataSource;

/**
 * BigService - Large-scale business service class
 * This class contains various business logic.
 * Contains approximately 1000 lines of code for demonstration purposes.
 */
public class BigService {

    private static final String DEFAULT_ENCODING = "UTF-8";
    private static final int MAX_RETRY_COUNT = 3;
    private static final long TIMEOUT_MILLISECONDS = 30000;
    private static final String DATE_FORMAT = "yyyy-MM-dd HH:mm:ss";

    private DataSource dataSource;
    private Map<String, Object> configurationCache;
    private List<String> activeConnections;
    private Set<String> validatedUsers;
    private Queue<String> pendingOperations;

    /**
     * Constructor
     */
    public BigService() {
        this.configurationCache = new HashMap<>();
        this.activeConnections = new ArrayList<>();
        this.validatedUsers = new HashSet<>();
        this.pendingOperations = new LinkedList<>();
        initializeService();
    }

    /**
     * Service initialization
     */
    private void initializeService() {
        System.out.println("Initializing BigService...");
        loadConfiguration();
        setupDatabaseConnection();
        validateSystemRequirements();
        System.out.println("BigService initialization completed.");
    }

    /**
     * Load configuration
     */
    private void loadConfiguration() {
        configurationCache.put("max_connections", 100);
        configurationCache.put("timeout", TIMEOUT_MILLISECONDS);
        configurationCache.put("retry_count", MAX_RETRY_COUNT);
        configurationCache.put("encoding", DEFAULT_ENCODING);
        configurationCache.put("date_format", DATE_FORMAT);

        for (int i = 0; i < 10; i++) {
            configurationCache.put("config_param_" + i, "value_" + i);
        }
    }

    /**
     * Database connection setup
     */
    private void setupDatabaseConnection() {
        System.out.println("Setting up database connection...");
        // Dummy connection setup process
        for (int i = 0; i < 5; i++) {
            activeConnections.add("connection_" + i);
            System.out.println("Created connection: connection_" + i);
        }
    }

    /**
     * System requirements validation
     */
    private void validateSystemRequirements() {
        System.out.println("Validating system requirements...");
        checkMemoryUsage();
        checkDiskSpace();
        checkNetworkConnectivity();
        System.out.println("System requirements validation completed.");
    }

    /**
     * Memory usage check
     */
    private void checkMemoryUsage() {
        Runtime runtime = Runtime.getRuntime();
        long totalMemory = runtime.totalMemory();
        long freeMemory = runtime.freeMemory();
        long usedMemory = totalMemory - freeMemory;

        System.out.println("Total Memory: " + totalMemory);
        System.out.println("Free Memory: " + freeMemory);
        System.out.println("Used Memory: " + usedMemory);

        if (usedMemory > totalMemory * 0.8) {
            System.out.println("WARNING: High memory usage detected!");
        }
    }

    /**
     * Disk space check
     */
    private void checkDiskSpace() {
        System.out.println("Checking disk space...");
        // Dummy disk space check
        for (int i = 0; i < 3; i++) {
            System.out.println("Disk " + i + ": Available space OK");
        }
    }

    /**
     * Network connectivity check
     */
    private void checkNetworkConnectivity() {
        System.out.println("Checking network connectivity...");
        String[] hosts = {"localhost", "database.example.com", "api.example.com"};

        for (String host : hosts) {
            System.out.println("Testing connection to: " + host);
            // Dummy connection test
            try {
                Thread.sleep(100);
                System.out.println("Connection to " + host + " successful");
            } catch (InterruptedException e) {
                System.out.println("Connection test interrupted");
            }
        }
    }

    /**
     * User authentication
     */
    public boolean authenticateUser(String username, String password) {
        if (username == null || username.isEmpty()) {
            System.out.println("ERROR: Username is null or empty");
            return false;
        }

        if (password == null || password.isEmpty()) {
            System.out.println("ERROR: Password is null or empty");
            return false;
        }

        System.out.println("Authenticating user: " + username);

        // ダミーの認証処理
        for (int i = 0; i < 10; i++) {
            System.out.println("Authentication step " + i);
            if (i == 5) {
                System.out.println("Validating credentials...");
            }
        }

        boolean isValid = username.length() > 3 && password.length() > 6;

        if (isValid) {
            validatedUsers.add(username);
            System.out.println("User " + username + " authenticated successfully");
        } else {
            System.out.println("Authentication failed for user: " + username);
        }

        return isValid;
    }

    /**
     * Session management
     */
    public String createSession(String username) {
        if (!validatedUsers.contains(username)) {
            System.out.println("ERROR: User not authenticated: " + username);
            return null;
        }

        String sessionId = "session_" + System.currentTimeMillis() + "_" + username;
        System.out.println("Creating session: " + sessionId);

        // Session creation process
        for (int i = 0; i < 15; i++) {
            System.out.println("Session creation step " + i);
            if (i == 7) {
                System.out.println("Generating session token...");
            }
            if (i == 12) {
                System.out.println("Storing session data...");
            }
        }

        System.out.println("Session created successfully: " + sessionId);
        return sessionId;
    }

    /**
     * Data validation
     */
    public boolean validateData(Map<String, Object> data) {
        if (data == null || data.isEmpty()) {
            System.out.println("ERROR: Data is null or empty");
            return false;
        }

        System.out.println("Validating data with " + data.size() + " fields");

        for (Map.Entry<String, Object> entry : data.entrySet()) {
            String key = entry.getKey();
            Object value = entry.getValue();

            System.out.println("Validating field: " + key);

            if (value == null) {
                System.out.println("WARNING: Null value for field: " + key);
                continue;
            }

            // Field-specific validation
            if (key.contains("email")) {
                if (!validateEmail(value.toString())) {
                    System.out.println("ERROR: Invalid email format: " + value);
                    return false;
                }
            } else if (key.contains("phone")) {
                if (!validatePhoneNumber(value.toString())) {
                    System.out.println("ERROR: Invalid phone number: " + value);
                    return false;
                }
            } else if (key.contains("date")) {
                if (!validateDate(value.toString())) {
                    System.out.println("ERROR: Invalid date format: " + value);
                    return false;
                }
            }

            System.out.println("Field " + key + " validation passed");
        }

        System.out.println("Data validation completed successfully");
        return true;
    }

    /**
     * Email format validation
     */
    private boolean validateEmail(String email) {
        System.out.println("Validating email: " + email);
        return email != null && email.contains("@") && email.contains(".");
    }

    /**
     * Phone number validation
     */
    private boolean validatePhoneNumber(String phone) {
        System.out.println("Validating phone number: " + phone);
        return phone != null && phone.matches("\\d{10,15}");
    }

    /**
     * Date format validation
     */
    private boolean validateDate(String date) {
        System.out.println("Validating date: " + date);
        try {
            LocalDateTime.parse(date, DateTimeFormatter.ofPattern(DATE_FORMAT));
            return true;
        } catch (Exception e) {
            return false;
        }
    }

    /**
     * Log operation
     */
    public void logOperation(String operation, String details) {
        String timestamp = LocalDateTime.now().format(DateTimeFormatter.ofPattern(DATE_FORMAT));
        String logEntry = String.format("[%s] %s: %s", timestamp, operation, details);

        System.out.println("LOG: " + logEntry);

        // Log file writing process (dummy)
        for (int i = 0; i < 5; i++) {
            System.out.println("Writing log entry, step " + i);
        }
    }

    /**
     * Cache management
     */
    public void manageCache(String key, Object value) {
        System.out.println("Managing cache for key: " + key);

        if (configurationCache.size() > 1000) {
            System.out.println("Cache size limit reached, cleaning up...");
            cleanupCache();
        }

        configurationCache.put(key, value);
        System.out.println("Cache updated for key: " + key);

        // Update cache statistics
        updateCacheStatistics();
    }

    /**
     * Cache cleanup
     */
    private void cleanupCache() {
        System.out.println("Starting cache cleanup...");

        int originalSize = configurationCache.size();
        Iterator<Map.Entry<String, Object>> iterator = configurationCache.entrySet().iterator();

        while (iterator.hasNext() && configurationCache.size() > 500) {
            iterator.next();
            iterator.remove();
        }

        int cleanedItems = originalSize - configurationCache.size();
        System.out.println("Cache cleanup completed. Removed " + cleanedItems + " items.");
    }

    /**
     * Update cache statistics
     */
    private void updateCacheStatistics() {
        System.out.println("Updating cache statistics...");
        System.out.println("Current cache size: " + configurationCache.size());
        System.out.println("Cache hit ratio: " + calculateCacheHitRatio());
    }

    /**
     * Calculate cache hit ratio
     */
    private double calculateCacheHitRatio() {
        // Dummy calculation
        return Math.random() * 0.3 + 0.7; // 70-100% range
    }

    /**
     * Backup processing
     */
    public void performBackup(String backupType) {
        System.out.println("Starting backup process: " + backupType);

        switch (backupType.toLowerCase()) {
            case "full":
                performFullBackup();
                break;
            case "incremental":
                performIncrementalBackup();
                break;
            case "differential":
                performDifferentialBackup();
                break;
            default:
                System.out.println("Unknown backup type: " + backupType);
                return;
        }

        System.out.println("Backup process completed: " + backupType);
    }

    /**
     * Full backup
     */
    private void performFullBackup() {
        System.out.println("Performing full backup...");

        for (int i = 0; i < 30; i++) {
            System.out.println("Full backup progress: " + (i + 1) + "/30");

            if (i == 10) {
                System.out.println("Backing up database...");
            } else if (i == 20) {
                System.out.println("Backing up configuration files...");
            } else if (i == 25) {
                System.out.println("Backing up user data...");
            }

            try {
                Thread.sleep(50);
            } catch (InterruptedException e) {
                System.out.println("Backup interrupted");
                return;
            }
        }

        System.out.println("Full backup completed successfully");
    }

    /**
     * Incremental backup
     */
    private void performIncrementalBackup() {
        System.out.println("Performing incremental backup...");

        for (int i = 0; i < 15; i++) {
            System.out.println("Incremental backup progress: " + (i + 1) + "/15");

            if (i == 5) {
                System.out.println("Identifying changed files...");
            } else if (i == 10) {
                System.out.println("Copying modified data...");
            }
        }

        System.out.println("Incremental backup completed successfully");
    }

    /**
     * Differential backup
     */
    private void performDifferentialBackup() {
        System.out.println("Performing differential backup...");

        for (int i = 0; i < 20; i++) {
            System.out.println("Differential backup progress: " + (i + 1) + "/20");

            if (i == 7) {
                System.out.println("Comparing with last full backup...");
            } else if (i == 15) {
                System.out.println("Copying differential data...");
            }
        }

        System.out.println("Differential backup completed successfully");
    }

    /**
     * レポート生成
     */
    public void generateReport(String reportType, Map<String, Object> parameters) {
        System.out.println("Generating report: " + reportType);

        if (parameters == null) {
            parameters = new HashMap<>();
        }

        // レポート生成の前処理
        prepareReportData(reportType, parameters);

        // レポートの種類に応じた処理
        switch (reportType.toLowerCase()) {
            case "sales":
                generateSalesReport(parameters);
                break;
            case "performance":
                generatePerformanceReport(parameters);
                break;
            case "user_activity":
                generateUserActivityReport(parameters);
                break;
            case "system_health":
                generateSystemHealthReport(parameters);
                break;
            default:
                System.out.println("Unknown report type: " + reportType);
                return;
        }

        // レポート生成の後処理
        finalizeReport(reportType);

        System.out.println("Report generation completed: " + reportType);
    }

    /**
     * レポートデータの準備
     */
    private void prepareReportData(String reportType, Map<String, Object> parameters) {
        System.out.println("Preparing report data for: " + reportType);

        for (int i = 0; i < 10; i++) {
            System.out.println("Data preparation step " + (i + 1) + "/10");

            if (i == 3) {
                System.out.println("Loading data sources...");
            } else if (i == 7) {
                System.out.println("Validating data integrity...");
            }
        }

        System.out.println("Report data preparation completed");
    }

    /**
     * 売上レポートの生成
     */
    private void generateSalesReport(Map<String, Object> parameters) {
        System.out.println("Generating sales report...");

        for (int i = 0; i < 25; i++) {
            System.out.println("Sales report generation step " + (i + 1) + "/25");

            if (i == 5) {
                System.out.println("Calculating total sales...");
            } else if (i == 10) {
                System.out.println("Analyzing sales trends...");
            } else if (i == 15) {
                System.out.println("Generating charts and graphs...");
            } else if (i == 20) {
                System.out.println("Formatting report layout...");
            }
        }

        System.out.println("Sales report generated successfully");
    }

    /**
     * パフォーマンスレポートの生成
     */
    private void generatePerformanceReport(Map<String, Object> parameters) {
        System.out.println("Generating performance report...");

        for (int i = 0; i < 20; i++) {
            System.out.println("Performance report generation step " + (i + 1) + "/20");

            if (i == 5) {
                System.out.println("Collecting performance metrics...");
            } else if (i == 10) {
                System.out.println("Analyzing system performance...");
            } else if (i == 15) {
                System.out.println("Creating performance summary...");
            }
        }

        System.out.println("Performance report generated successfully");
    }

    /**
     * ユーザーアクティビティレポートの生成
     */
    private void generateUserActivityReport(Map<String, Object> parameters) {
        System.out.println("Generating user activity report...");

        for (int i = 0; i < 18; i++) {
            System.out.println("User activity report generation step " + (i + 1) + "/18");

            if (i == 6) {
                System.out.println("Analyzing user behavior patterns...");
            } else if (i == 12) {
                System.out.println("Calculating user engagement metrics...");
            }
        }

        System.out.println("User activity report generated successfully");
    }

    /**
     * システムヘルスレポートの生成
     */
    private void generateSystemHealthReport(Map<String, Object> parameters) {
        System.out.println("Generating system health report...");

        for (int i = 0; i < 22; i++) {
            System.out.println("System health report generation step " + (i + 1) + "/22");

            if (i == 5) {
                System.out.println("Checking system resources...");
            } else if (i == 10) {
                System.out.println("Analyzing error logs...");
            } else if (i == 15) {
                System.out.println("Evaluating system stability...");
            }
        }

        System.out.println("System health report generated successfully");
    }

    /**
     * レポートの最終処理
     */
    private void finalizeReport(String reportType) {
        System.out.println("Finalizing report: " + reportType);

        for (int i = 0; i < 8; i++) {
            System.out.println("Report finalization step " + (i + 1) + "/8");

            if (i == 3) {
                System.out.println("Applying report formatting...");
            } else if (i == 6) {
                System.out.println("Saving report to file...");
            }
        }

        System.out.println("Report finalization completed");
    }

    /**
     * Updates customer name.
     * This method contains important business logic.
     * @param customerId Customer ID
     * @param newName New customer name
     */
    public void updateCustomerName(String customerId, String newName) {
        // Originally, complex processing such as database updates would be included here
        if (customerId == null || customerId.isEmpty()) {
            System.out.println("ERROR: Customer ID is null or empty.");
            return;
        }
        if (newName == null || newName.isEmpty()) {
            System.out.println("ERROR: New name is null or empty.");
            return;
        }
        System.out.println("Updating customer " + customerId + " to name " + newName);
        // ... About 50 lines of dummy processing ...
        for (int i = 0; i < 50; i++) {
            System.out.println("Processing step " + i);
        }
        System.out.println("Customer name updated successfully.");
    }

    /**
     * Get customer information
     */
    public Map<String, Object> getCustomerInfo(String customerId) {
        System.out.println("Retrieving customer information for ID: " + customerId);

        if (customerId == null || customerId.isEmpty()) {
            System.out.println("ERROR: Customer ID is null or empty");
            return null;
        }

        Map<String, Object> customerInfo = new HashMap<>();

        // Dummy customer information retrieval process
        for (int i = 0; i < 15; i++) {
            System.out.println("Customer info retrieval step " + (i + 1) + "/15");

            if (i == 5) {
                System.out.println("Querying customer database...");
                customerInfo.put("id", customerId);
                customerInfo.put("name", "Customer_" + customerId);
            } else if (i == 10) {
                System.out.println("Loading customer preferences...");
                customerInfo.put("email", "customer" + customerId + "@example.com");
                customerInfo.put("phone", "123-456-" + customerId);
            }
        }

        customerInfo.put("status", "active");
        customerInfo.put("created_date", LocalDateTime.now().toString());

        System.out.println("Customer information retrieved successfully");
        return customerInfo;
    }

    /**
     * Delete customer
     */
    public boolean deleteCustomer(String customerId) {
        System.out.println("Deleting customer: " + customerId);

        if (customerId == null || customerId.isEmpty()) {
            System.out.println("ERROR: Customer ID is null or empty");
            return false;
        }

        // Pre-deletion validation
        for (int i = 0; i < 10; i++) {
            System.out.println("Pre-deletion validation step " + (i + 1) + "/10");

            if (i == 3) {
                System.out.println("Checking customer dependencies...");
            } else if (i == 7) {
                System.out.println("Validating deletion permissions...");
            }
        }

        // Actual deletion process
        for (int i = 0; i < 20; i++) {
            System.out.println("Customer deletion step " + (i + 1) + "/20");

            if (i == 5) {
                System.out.println("Removing customer data...");
            } else if (i == 10) {
                System.out.println("Cleaning up related records...");
            } else if (i == 15) {
                System.out.println("Updating audit logs...");
            }
        }

        System.out.println("Customer " + customerId + " deleted successfully");
        return true;
    }

    /**
     * Order processing
     */
    public String processOrder(String customerId, List<String> items, double totalAmount) {
        System.out.println("Processing order for customer: " + customerId);

        if (customerId == null || customerId.isEmpty()) {
            System.out.println("ERROR: Customer ID is required");
            return null;
        }

        if (items == null || items.isEmpty()) {
            System.out.println("ERROR: Order items are required");
            return null;
        }

        if (totalAmount <= 0) {
            System.out.println("ERROR: Invalid total amount: " + totalAmount);
            return null;
        }

        String orderId = "ORDER_" + System.currentTimeMillis();
        System.out.println("Generated order ID: " + orderId);

        // Order processing steps
        for (int i = 0; i < 25; i++) {
            System.out.println("Order processing step " + (i + 1) + "/25");

            if (i == 3) {
                System.out.println("Validating customer account...");
            } else if (i == 7) {
                System.out.println("Checking item availability...");
            } else if (i == 12) {
                System.out.println("Processing payment...");
            } else if (i == 17) {
                System.out.println("Updating inventory...");
            } else if (i == 22) {
                System.out.println("Generating order confirmation...");
            }
        }

        System.out.println("Order processed successfully: " + orderId);
        return orderId;
    }

    /**
     * Inventory management
     */
    public void manageInventory(String action, String itemId, int quantity) {
        System.out.println("Managing inventory - Action: " + action + ", Item: " + itemId + ", Quantity: " + quantity);

        if (action == null || action.isEmpty()) {
            System.out.println("ERROR: Action is required");
            return;
        }

        if (itemId == null || itemId.isEmpty()) {
            System.out.println("ERROR: Item ID is required");
            return;
        }

        switch (action.toLowerCase()) {
            case "add":
                addInventory(itemId, quantity);
                break;
            case "remove":
                removeInventory(itemId, quantity);
                break;
            case "update":
                updateInventory(itemId, quantity);
                break;
            case "check":
                checkInventory(itemId);
                break;
            default:
                System.out.println("ERROR: Unknown inventory action: " + action);
                return;
        }

        System.out.println("Inventory management completed for item: " + itemId);
    }

    /**
     * Add inventory
     */
    private void addInventory(String itemId, int quantity) {
        System.out.println("Adding inventory for item: " + itemId + ", quantity: " + quantity);

        for (int i = 0; i < 12; i++) {
            System.out.println("Inventory addition step " + (i + 1) + "/12");

            if (i == 4) {
                System.out.println("Validating item information...");
            } else if (i == 8) {
                System.out.println("Updating inventory database...");
            }
        }

        System.out.println("Inventory added successfully");
    }

    /**
     * Remove inventory
     */
    private void removeInventory(String itemId, int quantity) {
        System.out.println("Removing inventory for item: " + itemId + ", quantity: " + quantity);

        for (int i = 0; i < 10; i++) {
            System.out.println("Inventory removal step " + (i + 1) + "/10");

            if (i == 3) {
                System.out.println("Checking available quantity...");
            } else if (i == 7) {
                System.out.println("Updating inventory records...");
            }
        }

        System.out.println("Inventory removed successfully");
    }

    /**
     * Update inventory
     */
    private void updateInventory(String itemId, int quantity) {
        System.out.println("Updating inventory for item: " + itemId + ", new quantity: " + quantity);

        for (int i = 0; i < 8; i++) {
            System.out.println("Inventory update step " + (i + 1) + "/8");

            if (i == 3) {
                System.out.println("Calculating inventory changes...");
            } else if (i == 6) {
                System.out.println("Applying inventory updates...");
            }
        }

        System.out.println("Inventory updated successfully");
    }

    /**
     * Check inventory
     */
    private void checkInventory(String itemId) {
        System.out.println("Checking inventory for item: " + itemId);

        for (int i = 0; i < 6; i++) {
            System.out.println("Inventory check step " + (i + 1) + "/6");

            if (i == 2) {
                System.out.println("Querying inventory database...");
            } else if (i == 4) {
                System.out.println("Calculating available quantity...");
            }
        }

        int availableQuantity = (int) (Math.random() * 100) + 1;
        System.out.println("Available quantity for item " + itemId + ": " + availableQuantity);
    }

    /**
     * Send notification
     */
    public void sendNotification(String recipient, String message, String type) {
        System.out.println("Sending notification to: " + recipient);
        System.out.println("Message: " + message);
        System.out.println("Type: " + type);

        if (recipient == null || recipient.isEmpty()) {
            System.out.println("ERROR: Recipient is required");
            return;
        }

        if (message == null || message.isEmpty()) {
            System.out.println("ERROR: Message is required");
            return;
        }

        // Notification sending process
        for (int i = 0; i < 15; i++) {
            System.out.println("Notification sending step " + (i + 1) + "/15");

            if (i == 3) {
                System.out.println("Validating recipient address...");
            } else if (i == 7) {
                System.out.println("Formatting notification message...");
            } else if (i == 11) {
                System.out.println("Delivering notification...");
            }
        }

        System.out.println("Notification sent successfully to: " + recipient);
    }

    /**
     * System shutdown
     */
    public void shutdownSystem() {
        System.out.println("Initiating system shutdown...");

        // Pre-shutdown processing
        for (int i = 0; i < 20; i++) {
            System.out.println("Shutdown preparation step " + (i + 1) + "/20");

            if (i == 3) {
                System.out.println("Saving pending operations...");
                savePendingOperations();
            } else if (i == 8) {
                System.out.println("Closing database connections...");
                closeDatabaseConnections();
            } else if (i == 13) {
                System.out.println("Clearing cache...");
                configurationCache.clear();
            } else if (i == 17) {
                System.out.println("Finalizing logs...");
                finalizeSystemLogs();
            }
        }

        System.out.println("System shutdown completed successfully");
    }

    /**
     * Save pending operations
     */
    private void savePendingOperations() {
        System.out.println("Saving " + pendingOperations.size() + " pending operations...");

        while (!pendingOperations.isEmpty()) {
            String operation = pendingOperations.poll();
            System.out.println("Saving operation: " + operation);
        }

        System.out.println("All pending operations saved");
    }

    /**
     * Close database connections
     */
    private void closeDatabaseConnections() {
        System.out.println("Closing database connections...");

        for (String connection : activeConnections) {
            System.out.println("Closing connection: " + connection);
        }

        activeConnections.clear();
        System.out.println("All database connections closed");
    }

    /**
     * Finalize system logs
     */
    private void finalizeSystemLogs() {
        System.out.println("Finalizing system logs...");

        for (int i = 0; i < 5; i++) {
            System.out.println("Log finalization step " + (i + 1) + "/5");
        }

        System.out.println("System logs finalized");
    }

    /**
     * Error handling
     */
    public void handleError(Exception error, String context) {
        System.out.println("Handling error in context: " + context);
        System.out.println("Error message: " + error.getMessage());

        // Record error log
        logOperation("ERROR", "Error in " + context + ": " + error.getMessage());

        // Processing according to error type
        if (error instanceof SQLException) {
            handleDatabaseError((SQLException) error);
        } else if (error instanceof IllegalArgumentException) {
            handleValidationError((IllegalArgumentException) error);
        } else if (error instanceof RuntimeException) {
            handleRuntimeError((RuntimeException) error);
        } else {
            handleGenericError(error);
        }

        System.out.println("Error handling completed for context: " + context);
    }

    /**
     * Handle database error
     */
    private void handleDatabaseError(SQLException error) {
        System.out.println("Handling database error: " + error.getSQLState());

        for (int i = 0; i < 8; i++) {
            System.out.println("Database error handling step " + (i + 1) + "/8");

            if (i == 3) {
                System.out.println("Attempting database reconnection...");
            } else if (i == 6) {
                System.out.println("Rolling back transaction...");
            }
        }

        System.out.println("Database error handled");
    }

    /**
     * Handle validation error
     */
    private void handleValidationError(IllegalArgumentException error) {
        System.out.println("Handling validation error: " + error.getMessage());

        for (int i = 0; i < 5; i++) {
            System.out.println("Validation error handling step " + (i + 1) + "/5");
        }

        System.out.println("Validation error handled");
    }

    /**
     * Handle runtime error
     */
    private void handleRuntimeError(RuntimeException error) {
        System.out.println("Handling runtime error: " + error.getMessage());

        for (int i = 0; i < 10; i++) {
            System.out.println("Runtime error handling step " + (i + 1) + "/10");

            if (i == 4) {
                System.out.println("Collecting error context...");
            } else if (i == 7) {
                System.out.println("Notifying administrators...");
            }
        }

        System.out.println("Runtime error handled");
    }

    /**
     * Handle generic error
     */
    private void handleGenericError(Exception error) {
        System.out.println("Handling generic error: " + error.getClass().getSimpleName());

        for (int i = 0; i < 6; i++) {
            System.out.println("Generic error handling step " + (i + 1) + "/6");
        }

        System.out.println("Generic error handled");
    }

    /**
     * Performance monitoring
     */
    public void monitorPerformance() {
        System.out.println("Starting performance monitoring...");

        long startTime = System.currentTimeMillis();

        // Monitor CPU usage
        monitorCpuUsage();

        // Monitor memory usage
        monitorMemoryUsage();

        // Monitor disk I/O
        monitorDiskIO();

        // Monitor network usage
        monitorNetworkUsage();

        long endTime = System.currentTimeMillis();
        long duration = endTime - startTime;

        System.out.println("Performance monitoring completed in " + duration + "ms");
    }

    /**
     * Monitor CPU usage
     */
    private void monitorCpuUsage() {
        System.out.println("Monitoring CPU usage...");

        for (int i = 0; i < 10; i++) {
            System.out.println("CPU monitoring step " + (i + 1) + "/10");
            double cpuUsage = Math.random() * 100;
            System.out.println("Current CPU usage: " + String.format("%.2f", cpuUsage) + "%");

            if (cpuUsage > 80) {
                System.out.println("WARNING: High CPU usage detected!");
            }
        }

        System.out.println("CPU monitoring completed");
    }

    /**
     * Monitor memory usage
     */
    private void monitorMemoryUsage() {
        System.out.println("Monitoring memory usage...");

        Runtime runtime = Runtime.getRuntime();

        for (int i = 0; i < 8; i++) {
            System.out.println("Memory monitoring step " + (i + 1) + "/8");

            long totalMemory = runtime.totalMemory();
            long freeMemory = runtime.freeMemory();
            long usedMemory = totalMemory - freeMemory;
            double usagePercentage = (double) usedMemory / totalMemory * 100;

            System.out.println("Memory usage: " + String.format("%.2f", usagePercentage) + "%");

            if (usagePercentage > 85) {
                System.out.println("WARNING: High memory usage detected!");
            }
        }

        System.out.println("Memory monitoring completed");
    }

    /**
     * Monitor disk I/O
     */
    private void monitorDiskIO() {
        System.out.println("Monitoring disk I/O...");

        for (int i = 0; i < 6; i++) {
            System.out.println("Disk I/O monitoring step " + (i + 1) + "/6");

            double readRate = Math.random() * 100;
            double writeRate = Math.random() * 100;

            System.out.println("Disk read rate: " + String.format("%.2f", readRate) + " MB/s");
            System.out.println("Disk write rate: " + String.format("%.2f", writeRate) + " MB/s");
        }

        System.out.println("Disk I/O monitoring completed");
    }

    /**
     * Monitor network usage
     */
    private void monitorNetworkUsage() {
        System.out.println("Monitoring network usage...");

        for (int i = 0; i < 7; i++) {
            System.out.println("Network monitoring step " + (i + 1) + "/7");

            double inboundTraffic = Math.random() * 1000;
            double outboundTraffic = Math.random() * 1000;

            System.out.println("Inbound traffic: " + String.format("%.2f", inboundTraffic) + " KB/s");
            System.out.println("Outbound traffic: " + String.format("%.2f", outboundTraffic) + " KB/s");
        }

        System.out.println("Network monitoring completed");
    }

    /**
     * Security check
     */
    public void performSecurityCheck() {
        System.out.println("Starting security check...");

        // Check access permissions
        checkAccessPermissions();

        // Validate security settings
        validateSecuritySettings();

        // Perform vulnerability scan
        performVulnerabilityScan();

        // Review security logs
        reviewSecurityLogs();

        System.out.println("Security check completed");
    }

    /**
     * Check access permissions
     */
    private void checkAccessPermissions() {
        System.out.println("Checking access permissions...");

        for (int i = 0; i < 12; i++) {
            System.out.println("Permission check step " + (i + 1) + "/12");

            if (i == 3) {
                System.out.println("Validating user permissions...");
            } else if (i == 7) {
                System.out.println("Checking file system permissions...");
            } else if (i == 10) {
                System.out.println("Verifying database access rights...");
            }
        }

        System.out.println("Access permissions check completed");
    }

    /**
     * Validate security settings
     */
    private void validateSecuritySettings() {
        System.out.println("Validating security settings...");

        for (int i = 0; i < 9; i++) {
            System.out.println("Security settings validation step " + (i + 1) + "/9");

            if (i == 3) {
                System.out.println("Checking encryption settings...");
            } else if (i == 6) {
                System.out.println("Validating authentication configuration...");
            }
        }

        System.out.println("Security settings validation completed");
    }

    /**
     * Perform vulnerability scan
     */
    private void performVulnerabilityScan() {
        System.out.println("Performing vulnerability scan...");

        for (int i = 0; i < 15; i++) {
            System.out.println("Vulnerability scan step " + (i + 1) + "/15");

            if (i == 5) {
                System.out.println("Scanning for known vulnerabilities...");
            } else if (i == 10) {
                System.out.println("Checking for security patches...");
            }
        }

        System.out.println("Vulnerability scan completed");
    }

    /**
     * Review security logs
     */
    private void reviewSecurityLogs() {
        System.out.println("Reviewing security logs...");

        for (int i = 0; i < 8; i++) {
            System.out.println("Security log review step " + (i + 1) + "/8");

            if (i == 3) {
                System.out.println("Analyzing failed login attempts...");
            } else if (i == 6) {
                System.out.println("Checking for suspicious activities...");
            }
        }

        System.out.println("Security log review completed");
    }

    /**
     * Data synchronization
     */
    public void synchronizeData(String sourceSystem, String targetSystem) {
        System.out.println("Starting data synchronization from " + sourceSystem + " to " + targetSystem);

        if (sourceSystem == null || sourceSystem.isEmpty()) {
            System.out.println("ERROR: Source system is required");
            return;
        }

        if (targetSystem == null || targetSystem.isEmpty()) {
            System.out.println("ERROR: Target system is required");
            return;
        }

        // Prepare data synchronization
        prepareSynchronization(sourceSystem, targetSystem);

        // Extract data
        extractData(sourceSystem);

        // Transform data
        transformData();

        // Load data
        loadData(targetSystem);

        // Verify synchronization
        verifySynchronization(sourceSystem, targetSystem);

        System.out.println("Data synchronization completed successfully");
    }

    /**
     * Prepare synchronization
     */
    private void prepareSynchronization(String sourceSystem, String targetSystem) {
        System.out.println("Preparing synchronization between " + sourceSystem + " and " + targetSystem);

        for (int i = 0; i < 10; i++) {
            System.out.println("Synchronization preparation step " + (i + 1) + "/10");

            if (i == 3) {
                System.out.println("Establishing connections...");
            } else if (i == 7) {
                System.out.println("Validating data schemas...");
            }
        }

        System.out.println("Synchronization preparation completed");
    }

    /**
     * Extract data
     */
    private void extractData(String sourceSystem) {
        System.out.println("Extracting data from " + sourceSystem);

        for (int i = 0; i < 20; i++) {
            System.out.println("Data extraction step " + (i + 1) + "/20");

            if (i == 5) {
                System.out.println("Querying source database...");
            } else if (i == 10) {
                System.out.println("Processing data records...");
            } else if (i == 15) {
                System.out.println("Validating extracted data...");
            }
        }

        System.out.println("Data extraction completed");
    }

    /**
     * Transform data
     */
    private void transformData() {
        System.out.println("Transforming data...");

        for (int i = 0; i < 15; i++) {
            System.out.println("Data transformation step " + (i + 1) + "/15");

            if (i == 5) {
                System.out.println("Applying data mapping rules...");
            } else if (i == 10) {
                System.out.println("Performing data cleansing...");
            }
        }

        System.out.println("Data transformation completed");
    }

    /**
     * Load data
     */
    private void loadData(String targetSystem) {
        System.out.println("Loading data into " + targetSystem);

        for (int i = 0; i < 18; i++) {
            System.out.println("Data loading step " + (i + 1) + "/18");

            if (i == 6) {
                System.out.println("Inserting new records...");
            } else if (i == 12) {
                System.out.println("Updating existing records...");
            }
        }

        System.out.println("Data loading completed");
    }

    /**
     * Verify synchronization
     */
    private void verifySynchronization(String sourceSystem, String targetSystem) {
        System.out.println("Verifying synchronization between " + sourceSystem + " and " + targetSystem);

        for (int i = 0; i < 12; i++) {
            System.out.println("Synchronization verification step " + (i + 1) + "/12");

            if (i == 4) {
                System.out.println("Comparing record counts...");
            } else if (i == 8) {
                System.out.println("Validating data integrity...");
            }
        }

        System.out.println("Synchronization verification completed");
    }

    /**
     * Main method - for testing
     */
    public static void main(String[] args) {
        System.out.println("BigService Demo Application");
        System.out.println("==========================");

        BigService service = new BigService();

        // Test basic functions
        System.out.println("\n--- Testing Basic Functions ---");
        service.authenticateUser("testuser", "password123");
        service.createSession("testuser");

        // Test customer management
        System.out.println("\n--- Testing Customer Management ---");
        service.updateCustomerName("CUST001", "New Customer Name");
        Map<String, Object> customerInfo = service.getCustomerInfo("CUST001");

        // Test report generation
        System.out.println("\n--- Testing Report Generation ---");
        Map<String, Object> reportParams = new HashMap<>();
        reportParams.put("start_date", "2024-01-01");
        reportParams.put("end_date", "2024-12-31");
        service.generateReport("sales", reportParams);

        // Test performance monitoring
        System.out.println("\n--- Testing Performance Monitoring ---");
        service.monitorPerformance();

        // Test security check
        System.out.println("\n--- Testing Security Check ---");
        service.performSecurityCheck();

        System.out.println("\n--- Demo Completed ---");
        System.out.println("BigService demo application finished successfully.");
    }
}
