/* Objective: Since Windows 10 File Explorer search seems messed-up on my laptop 
(and computers of at least some others reporting online) since late 2019,
try to make something for finding files/folders on my laptop while waiting for a fix!
First just look at file/folder names (might include option to match text within files later)

v3 12Jan2020

Done in this iteration/version:
Dealt with a bug found by chance...
--Problem: Found that some invalid entries for start path, e.g. "For C:\" (which I entered accidentally), 
did not trigger my "No valid path supplied" message, and any previous output stayed in the display area. 
(However, though the user does not receive feedback, the program did not crash and responded normally to a 'regular' subsequent search.)
--Cause: InvalidPathException thrown from Paths.get(startText)
--Solution: Handled the exception to divert to the "No valid path supplied" display 
as in the 2 set-off sections of code marked by comments beginning with "--v3" 


Next, might address:
--Possible to allow a search to be aborted (while displaying items found up to that point)
without closing the program window (& have the button text toggle to a message indicating this option)?

 */

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Font;
import java.awt.Insets;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.stream.Stream;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;

class FindFileOrFolder_v3
{
    String missingStartMessage = "";
    String missingTargetMessage = "";

    int walkDepth = 1; // --specifies how many subdirectory levels to go down when collecting files to access
                       //   initialized to default 1 (do not look in subdirectories)
        
    // GUI components...
        
    JLabel startFolderJLabel = new JLabel("  Enter the path of the folder from within which you want to (start your) search..."); 
    JTextArea startFolderTextArea = new JTextArea(2, 60); // input to specify foolder within which to (start) searching
    JPanel panelForStartComponents = new JPanel(new BorderLayout()); // to hold the above pair of components
  
    JButton depthButton = new JButton("Search in subfolders of the starting folder also"); 

    JLabel targetNameJLabel = new JLabel("  Enter the name or partial name of a file or folder you want to find..."); 
    JTextArea targetNameTextArea = new JTextArea(2, 60); // input to specify file/folder names for which to search       
    JPanel panelForTargetComponents = new JPanel(new BorderLayout()); // to hold the above pair of components    
    
    JPanel panelForInputs = new JPanel(new BorderLayout()); // to hold panelForStartComponents, depthButton, panelForTargetComponents
    
    
    JButton findButton = new JButton("Find files/folders"); 
    JTextArea displayTextArea = new JTextArea(40, 100); // displays output, i.e. paths for files/folders found    
    JPanel panelForFindButtonAndOutput = new JPanel(new BorderLayout()); // to hold the above pair of components
    
    
    JFrame frame = new JFrame("FindFileOrFolder"); // to hold all above (sub)panels
    
    
    FindFileOrFolder_v3() // constructor, called when main method runs
    {   
        panelForStartComponents.add(startFolderJLabel, BorderLayout.NORTH);      
        startFolderTextArea.setLineWrap(true); 
        startFolderTextArea.setMargin(new Insets(5, 5, 5, 5));            
        panelForStartComponents.add(new JScrollPane(startFolderTextArea), BorderLayout.SOUTH);      
        panelForInputs.add(panelForStartComponents, BorderLayout.NORTH);      

        panelForTargetComponents.add(targetNameJLabel, BorderLayout.NORTH);  
        targetNameTextArea.setLineWrap(true); 
        targetNameTextArea.setMargin(new Insets(5, 5, 5, 5));            
        panelForTargetComponents.add(new JScrollPane(targetNameTextArea), BorderLayout.SOUTH);      
        panelForInputs.add(panelForTargetComponents, BorderLayout.SOUTH);          
        
        findButton.addActionListener(actionEvent ->
            { // (the 'actionPerformed' method body of the implicit ActionListner...)
                String startText = startFolderTextArea.getText().trim();
                
                
                
                
                
                // --v3 alterations made to handle possibility that InvalidPathException is thrown...
                Path startPath = null; // path to folder within which to (start) searching
                boolean startPathValid = true;
                try 
                {   
                    startPath = Paths.get(startText); // ...for some start inputs on this call
                } 
                catch (Exception e) // to handle possible InvalidPathException
                {
                    startPathValid = false;
                }
                Path validatedStartPath = startPath; // (need an effectively final variable for use later in a lambda)
                
                if (startPathValid) // even if real path input, want to check that it a folder (cf a file), so reassign to...
                {
                    startPathValid = Files.isDirectory(startPath); // (as empty string arg seems to generate Path regarded 
                    // as valid (root/current folder?), so for now including check re startText.isEmpty() below)
                }
                                
                
                
                
                
                final String target = targetNameTextArea.getText(); // (partial) names of files/folders for which to search          

                if (startText.isEmpty() || !startPathValid)
                {
                    missingStartMessage = "No valid start path supplied" + "\n";
                }                
                
                if (target.isEmpty())
                {                
                    missingTargetMessage = "No search term supplied" + "\n";
                }

                if (!startText.isEmpty() && startPathValid && !target.isEmpty())
                { // only run process below if target text and valid start path have been supplied (avoid wasteful processing)

                    // first, clear any previous message or search results and display a message to say the search is in progress    
                    displayTextArea.setForeground(Color.GREEN); 
                    displayTextArea.setFont(new Font("SERIF", Font.BOLD, 20));                 
                    displayTextArea.setText("Search in progress...");                         
                        
                    SwingUtilities.invokeLater(() -> // (want the above progress' message to appear first if search takes a while)
                    {                        
                            displayTextArea.setForeground(Color.BLACK);
                            displayTextArea.setFont(null);// this seems to work to restore the font to default (as desired)      
                            displayTextArea.setText(null); // clear any previous text before displaying the results

                            try 
                            {
       
                                
                                
                                // --v3 alteration: first arg changed from startPath due to changes above      
                                Stream<Path> targetStream = Files.find(validatedStartPath, walkDepth,


                                        
                                        (p,a) -> 
                                                !isHiddenHandler(p) && // to exclude hidden (temporary etc) files
                                                p.getFileName().toString().contains(target)); 

                                targetStream.forEach(p -> displayTextArea.append(p.toString() + "\n")); // print paths found in output/display area   

                                if (displayTextArea.getText().equals(""))
                                {
                                    displayTextArea.setForeground(Color.BLUE);
                                    displayTextArea.setText("No results found");
                                } // (seems inelegant, but have not thought of a way to do directly from the stream code yet)

                            }
                            catch (IOException ex)
                            {
                                if (ex.getClass().getName().equals("java.nio.file.NoSuchFileException"))          
                                {
                                    missingInputsMessage();
                                } // (probably not needed now, though, as should not get to try clause without valid start path)      
                            } 
                        }
                    );
                }
                else
                {
                    missingInputsMessage();
                } 
            } 
        );         
        findButton.setMargin(new Insets(10, 10, 10, 10));
        findButton.setFont(new Font("SansSerif", Font.BOLD, 20));         
        panelForFindButtonAndOutput.add(findButton, BorderLayout.NORTH);         
        
        depthButton.addActionListener(actionEvent ->
            {                      
                if (walkDepth == 1)
                {
                    walkDepth = Integer.MAX_VALUE;
                    depthButton.setText("Search in the starting folder only");
                }                           
                else // (walkDepth is Integer.MAX_VALUE)
                {
                    walkDepth = 1;
                    depthButton.setText("Search in subfolders of the starting folder also");
                }
            } 
        ); // toggles walk dept between no-subfolders and all-subfolders
        panelForInputs.add(depthButton, BorderLayout.CENTER);   

        displayTextArea.setEditable(false);
        displayTextArea.setLineWrap(true); 
        displayTextArea.setMargin(new Insets(5, 5, 5, 5)); 
        panelForFindButtonAndOutput.add(new JScrollPane(displayTextArea), BorderLayout.SOUTH); 
        
        frame.add(panelForInputs, BorderLayout.NORTH); 
        frame.add(panelForFindButtonAndOutput, BorderLayout.SOUTH); 
        frame.setResizable(false); // (buttons disappear if user drags frame bottom up, 
        // while if it's dragged down, the extra space just appears as a gap between the panels,
        // so just hard-coding big displayTextArea for the moment;
        // looking briefly online, see descriptions/code for how to make rezizable by dragging, but not trivial
        frame.setVisible(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    
        frame.pack(); // (may need to keep this positioned last)
    }
    
    void missingInputsMessage() // puts message in display area if one or both user inputs missing/incorrect
    {
        displayTextArea.setForeground(Color.red);
        displayTextArea.setText(missingStartMessage + missingTargetMessage);    
        missingStartMessage = ""; // reset for future clicks 
        missingTargetMessage = ""; // (ditto)
    }
    
    boolean isHiddenHandler (Path p) // as Files.isHidden(...) throws checked exception...
    { // ...easier to handle it externally than in stream coded in findButton's addActionListener above
        boolean result = false;
        try
        {
            result = Files.isHidden(p);
        } 
        catch (IOException ex)
        {
            System.out.println(ex);
        }
        return result;
    }
    
    public static void main(String[] args)
    {   
        new FindFileOrFolder_v3();  
    }
}