WgetCommand for file downloading

- Supports downloading web pages and files.
- Handles common wget flags like -O for specifying output files and -q for quiet mode.
- Uses HttpURLConnection for HTTP requests and manages output to both files and standard output.
- Error handling for invalid flags and multiple URL inputs.

Author: siddhant-vij

src/com/unixtools/command/networking/WgetCommand.java

@@ -1,5 +1,96 @@
 package com.unixtools.command.networking;
 
-public class WgetCommand {
-  
+import com.unixtools.core.Command;
+
+import java.io.*;
+import java.net.HttpURLConnection;
+import java.net.URI;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.List;
+
+public class WgetCommand implements Command {
+  private static final String VALID_FLAGS = "Oq";
+  private String outputFileName = null;
+  private boolean quietMode = false;
+
+  @Override
+  public void execute(String[] args) {
+    List<String> flags = new ArrayList<>();
+    List<String> urls = new ArrayList<>();
+    parseArguments(args, flags, urls);
+
+    if (!areFlagsValid(flags)) {
+      System.out.println("Invalid flags. Valid flags are: " + VALID_FLAGS);
+      return;
+    }
+
+    if (urls.isEmpty()) {
+      System.out.println("wget: URL not specified.");
+      return;
+    }
+
+    if (urls.size() > 1) {
+      System.out.println("wget: Only one URL can be specified.");
+      return;
+    }
+
+    String url = urls.get(0);
+    downloadFile(url);
+  }
+
+  private void parseArguments(String[] args, List<String> flags, List<String> urls) {
+    for (int i = 0; i < args.length; i++) {
+      if (args[i].startsWith("-")) {
+        for (char flag : args[i].substring(1).toCharArray()) {
+          if (flag == 'O' && i + 1 < args.length) {
+            outputFileName = args[++i];
+          } else if (flag == 'q') {
+            quietMode = true;
+          } else {
+            flags.add(String.valueOf(flag));
+          }
+        }
+      } else {
+        urls.add(args[i]);
+      }
+    }
+  }
+
+  private boolean areFlagsValid(List<String> flags) {
+    for (String flag : flags) {
+      if (!VALID_FLAGS.contains(flag)) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  private void downloadFile(String urlString) {
+    try {
+      URL url = URI.create(urlString).toURL();
+      HttpURLConnection connection = (HttpURLConnection) url.openConnection();
+      try (BufferedInputStream in = new BufferedInputStream(connection.getInputStream());
+          OutputStream out = determineOutputStream()) {
+        byte[] buffer = new byte[1024];
+        int count;
+        while ((count = in.read(buffer)) != -1) {
+          out.write(buffer, 0, count);
+        }
+        if (!quietMode) {
+          System.out.println("\nDownload completed: " + urlString);
+        }
+      }
+    } catch (IOException e) {
+      System.out.println("Error downloading file: " + e.getMessage());
+    }
+  }
+
+  private OutputStream determineOutputStream() throws FileNotFoundException {
+    if (outputFileName != null) {
+      return new FileOutputStream(outputFileName);
+    } else {
+      return System.out;
+    }
+  }
 }

src/com/unixtools/core/CommandFactory.java

@@ -35,6 +35,8 @@ public static Command getCommand(String commandName) {
         return new PingCommand();
       case "curl":
         return new CurlCommand();
+      case "wget":
+        return new WgetCommand();
       default:
         return null;
     }