//File:  rm.java
//CS 471 - Operating Systems Project
//Dennis Pereira, Ely Soto, John Cavalieri

// This file deletes a file or a directory and all of its contents.  It handles multiple arguments.

import  java.io.*;

public class rm extends VMachine
{
    public rm()
    {
    }
    
    public void run()
    {
        
        try
        {
            
            File fileObject;
            
            for(int i = 0;i<args.length;i++)		// Keep removing until no more arguments
            {
                fileObject = new File(sysapi.findUser(owner).getcurrentPath() + args[i]);	// Set file or directory to delete
                
                if(fileObject.exists())
                {
                    if(fileObject.isFile())		// If it is a file delete it
                    {
                        
                        if(!fileObject.delete())	// Error checking if file is locked.
                        {//If it still exists, file must still be locked
                            
                            sysapi.Write(OUT, "Error - " + fileObject.getName() + " in Use.\n");
                        }
                    }
                    else
                    {//Is Directory				// If it is a directory delete all the files first and then 
									// the directory at the users choice.
                        if(!fileObject.delete())
                        {
                            sysapi.Write(OUT,"Do you wish to delete the contents of this directory and subdirectories? (Y/N)");
                            String delete = sysapi.Read(IN).trim().toLowerCase();
                            if(delete.compareTo("y") == 0)		// If user says yes delete the entire directory and its contents.
                            {
                                DeleteDir(fileObject);
                                
                                if(!fileObject.delete())
                                {//If it still exists, file must still be locked	// Error checking for locked files.
                                    try
                                    {
                                        sysapi.Write(OUT, "Error - Directory could not be deleted.\n");
                                    }
                                    catch(IOException ioex)
                                    {
                                        System.out.println("rm threw Exception: " + ioex);
                                    }
                                }
                            }
                        }
                    }
                }
                else
                {
                    sysapi.Write(OUT, "Error -- File or directory does not exist.\n");	// Error code for it the directory doesn't exist.
                }
            }
            
        }
        catch (Exception err)
        {
            System.out.println("rm threw Exception: " + err);
        }
        
        sysapi.Exit(vmh,owner);
    }
    
    void DeleteDir(File fileObject)			// Deletes the directory by deleting all of the files first.
    {
        File[] filelist = fileObject.listFiles();
        
        for(int i=0;i<filelist.length;i++)
        {
            if(filelist[i].isDirectory())
            {
                if(!filelist[i].delete())
                {
                    DeleteDir(filelist[i]);
                    filelist[i].delete();
                }
            }
            else
            {
                if(!filelist[i].delete())
                {
                    try
                    {
                        sysapi.Write(OUT, "Error - " + filelist[i].getName() + " in Use.\n");
                    }
                    catch(IOException ioex)
                    {
                        System.out.println("rm threw Exception: " + ioex);
                    }
                }
            }
            
        }
    }
    
}