ConsoleIDM.java

import java.io.*;
import java.net.*;
import java.nio.file.*;
import java.util.Date;

public class ConsoleIDM {
    public static volatile boolean paused = false;

    public static void main(String args[]) throws Exception {
        System.out.println("************************************");
        System.out.println("*       Welcome to Console IDM      *");
        System.out.println("************************************");
        
        // Menu-driven interface
        while (true) {
           
            System.out.println("\n1. Download File");
            System.out.println("2. History");
            System.out.println("3. Exit");
            System.out.print("\nEnter your choice: ");
            
            BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
            int choice = Integer.parseInt(reader.readLine());
            
            switch (choice) {
                case 2:
                    DBI.getHistory();
                    break;
                case 1:
                    if (args.length == 0) {
                        System.out.println("Please provide the URLs as command-line arguments.");
                    } else {
                        for (String url : args) {
                            downloadFile(url);
                        }
                    }
                    break;
                case 3:
                    System.out.println("Exiting...");
                    System.exit(0);
                    break;
                default:
                    System.out.println("Invalid choice. Please enter a valid option.");
            }
        }
    }
    


    // Method to download a file from a given URL
    private static void downloadFile(String urlToDownload) {
        try {
            URL u = new URL(urlToDownload);
            URLConnection uc = u.openConnection();

            // Display information about the file to be downloaded
            System.out.println("\nDownloading file from:\n" + urlToDownload);
            System.out.println("------------------------------------------------------");
            System.out.println("Date: " + new Date(uc.getDate()));
            System.out.println("Content-Type: " + uc.getContentType());
            System.out.println("Expires: " + uc.getExpiration());
            System.out.println("Last-Modified: " + new Date(uc.getLastModified()));
            long len = uc.getContentLengthLong();
            System.out.println("Content-Length: " + len);

            // Check if the file size is greater than 0
            if (len > 0) {
                // Extract file name from URL
                Path path = Paths.get(u.getPath());
                String fileName = path.getFileName().toString();

                int numThreads = 4; // Number of threads to use
                long partSize = len / numThreads; // Calculate part size

                // Create and start threads for downloading parts of the file
                DownloadThread[] threads = new DownloadThread[numThreads];
                for (int i = 0; i < numThreads; i++) {
                    long startByte = i * partSize;
                    long endByte = (i == numThreads - 1) ? len : (i + 1) * partSize - 1;
                    threads[i] = new DownloadThread(urlToDownload, fileName, (int) startByte, (int) endByte); // Casting long to int
                    threads[i].start();
                }

                // Monitor progress and allow pausing/resuming
                long totalBytesDownloaded = 0;
                long startTime = System.currentTimeMillis();
                long lastDownloadedBytes = 0; // Keep track of last downloaded bytes for calculating speed when paused
                while (totalBytesDownloaded < len) {
                    totalBytesDownloaded = 0;
                    for (int i = 0; i < numThreads; i++) {
                        totalBytesDownloaded += threads[i].getDownloadedBytes();
                    }

                    // Calculate download speed
                    long currentTime = System.currentTimeMillis();
                    long elapsedTime = currentTime - startTime;
                    double downloadSpeed = (totalBytesDownloaded - lastDownloadedBytes) / (double) elapsedTime * 1000; // Bytes per second
                    downloadSpeed = downloadSpeed / 1024; // Kilobytes per second
                    lastDownloadedBytes = totalBytesDownloaded; // Update last downloaded bytes

                    printProgressBar(totalBytesDownloaded, len, downloadSpeed);
                    Thread.sleep(1000); // Update progress every second

                    // Check for user input to pause/resume download
                    if (System.in.available() > 0) {
                        char input = (char) System.in.read();
                        System.in.skip(System.in.available()); // Clear input buffer
                        if (input == 'p') {
                            paused = true;
                            System.out.println("\nDownload paused. Press 'r' to resume...");
                            continue; // Skip remaining logic and wait for next input
                        } else if (input == 'r') {
                            paused = false;
                            synchronized (ConsoleIDM.class) {
                                ConsoleIDM.class.notifyAll();
                            }
                            System.out.println("\nResuming download...");
                            startTime = System.currentTimeMillis(); // Reset start time to maintain accurate speed calculation
                        } else {
                            System.out.println("\nInvalid input. Press 'p' to pause or 'r' to resume.");
                        }
                    }
                }

                // Log downloaded file
                logDownloadedFile(fileName, len, urlToDownload);

                System.out.println("\nDownload completed. Saved as: " + fileName);
                System.out.println("------------------------------------------------------");
            } else {
                System.out.println("\nNo content available for download.");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // Method to print progress bar and download speed
    private static void printProgressBar(long current, long total, double downloadSpeed) {
        int progress = (int) (100.0 * current / total);
        System.out.printf("\r[%d%%] [%d/%d] Download Speed: %.2f KB/s", progress, current, total, downloadSpeed);
    }

    // Method to log downloaded file
    public static void logDownloadedFile(String fileName, long size, String urlToDownload) {
        try {
            FileWriter writer = new FileWriter("downloaded_files.txt", true);
            BufferedWriter bufferWriter = new BufferedWriter(writer);
            bufferWriter.write(fileName + " - " + size + " bytes - " + new Date() + "\n");
            bufferWriter.close();

            // Save download history to database
            DBI.saveDownloadHistory(urlToDownload, fileName, size, new Date(), new Date(), true);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}