/***
 *	Prova A2 - Ismael
 *
 */
import javax.swing.*;
import javax.swing.BorderFactory;
import javax.swing.table.*;
import javax.swing.border.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
import java.io.*;

/*
 *	Classe principal
 */
public class Matriz extends JFrame {
  	private File arqTemp;
  	private File arqOrigemA;
  	private File arqOrigemB;
  	private File arqResult;
  
  	public static void main(String[] args) {
    	Matriz frame = new Matriz();
    	frame.pack();
    	frame.setVisible(true);
    }
    /*
     *	Construtor
     */
  	public Matriz() {
    	super("Matriz");        
    	setSize(600, 400);
	  	setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    	Container cont = getContentPane();
	  	cont.setLayout(new BorderLayout());
	  	        
	    final JPanel painel_tables = new JPanel(new GridLayout(1, 3, 10, 10));

    	DefaultTableModel model = new DefaultTableModel();   
    	final JTable tabA = new JTable(3,3); 
    	tabA.setPreferredScrollableViewportSize(new Dimension(200, 70));
    	JScrollPane scrollPaneA = new JScrollPane(tabA); 
    	   
    	final JTable tabB = new JTable(3,3); 
    	tabB.setPreferredScrollableViewportSize(new Dimension(200, 70));
    	JScrollPane scrollPaneB = new JScrollPane(tabB);
    	    
    	final JTable tabC = new JTable(3,3); 
    	tabC.setPreferredScrollableViewportSize(new Dimension(200, 70));
    	JScrollPane scrollPaneC = new JScrollPane(tabC);    

    	painel_tables.add(scrollPaneA);
    	painel_tables.add(scrollPaneB);
    	painel_tables.add(scrollPaneC);
    	cont.add(painel_tables, BorderLayout.CENTER);
    
    	final JLabel label1 = new JLabel();
    	JScrollPane scrollPane1 = new JScrollPane(label1);    	
    	final JLabel label2 = new JLabel();
    	JScrollPane scrollPane2 = new JScrollPane(label2); 
    	final JLabel label3 = new JLabel();
    	JScrollPane scrollPane3 = new JScrollPane(label3); 
    	
    	JButton btLoadA = new JButton("Carrega A");
    	JButton btLoadB = new JButton("Carrega B");
    	JButton btCalcula = new JButton("Calcula");    
    	final JButton btSave = new JButton("Save");

    	btLoadA.addActionListener(new ActionListener() {
      	public void actionPerformed(ActionEvent E) {
			    CarregaMatrizes(arqOrigemA, label1, tabA);
			    btSave.setVisible(false);
      	}
    	});
    	btLoadB.addActionListener(new ActionListener() {
      	public void actionPerformed(ActionEvent E) {
  				CarregaMatrizes(arqOrigemB, label2, tabB);
  				btSave.setVisible(false);
      	}
    	});
    	btSave.addActionListener(new ActionListener() {
      	public void actionPerformed(ActionEvent E) {
  				SalvarResultado(arqResult, label3, tabC);
      	}
    	});
    	btCalcula.addActionListener(new ActionListener() {
      	public void actionPerformed(ActionEvent e) {
      		Resultado(tabA, tabB, tabC); 
      		btSave.setVisible(true);       		
      	}	
    	});

    	JPanel painel_botoes = new JPanel(new GridLayout(2, 3, 10, 10));
    	painel_botoes.add(btLoadA);
    	painel_botoes.add(btLoadB);
    	JPanel p = new JPanel(); 
    	p.setBorder(BorderFactory.createEtchedBorder());
    	p.add(btCalcula); p.add(btSave); btSave.setVisible(false);
    	painel_botoes.add(p);
    	painel_botoes.add(scrollPane1);
    	painel_botoes.add(scrollPane2);
    	painel_botoes.add(scrollPane3);
    	cont.add(painel_botoes, BorderLayout.SOUTH);
    	show();
	}
	
	public void CarregaMatrizes(File arquivo, JLabel lbl, JTable tab) {
		arqTemp = ObtemArquivo();
    try {
    	if (arqTemp != null && !(arqTemp.getName().equals(""))) {
      	arquivo = arqTemp;	
	      double tMatriz[][] = LerArquivo(arquivo);        
	    	for (int i = 0; i < tMatriz.length; i++) {
	      	for (int j = 0; j < tMatriz[0].length; j++) {
         		tab.setValueAt(new Double(tMatriz[i][j]), i, j);
	      	}
	    	}
		  	lbl.setText(arquivo.getAbsolutePath());
		    JOptionPane.showMessageDialog(this, "Matriz carregada!");
      }
    }
    catch (Exception E2) {
    }
  }
	public void SalvarResultado(File arquivo, JLabel lbl, JTable tab) {
		arqTemp = ObtemArquivo();
    try {
    	if (arqTemp != null && !(arqTemp.getName().equals(""))) {
      	arquivo = arqTemp;
      	double tMatriz[][] = new double[tab.getRowCount()][tab.getColumnCount()];	
	    	for (int i = 0; i < tMatriz.length; i++) {
	      	for (int j = 0; j < tMatriz[0].length; j++) {
         		tMatriz[i][j] = ((Double)tab.getValueAt(i, j)).doubleValue();
	      	}
	    	}
	      SalvarArquivo(arquivo, tMatriz);        
		  	lbl.setText(arquivo.getAbsolutePath());
        JOptionPane.showMessageDialog(this, "Matriz salva!");
      }
    }
    catch (Exception E2) {
    }
  }
	public void Resultado(JTable tabA, JTable tabB, JTable tabC) {
  	int i, j, k, nLins, nCols, nInner;
    double res = 0;
    double v1, v2;
      
    nLins = tabA.getRowCount();
    nCols = tabB.getColumnCount();
    nInner= tabA.getColumnCount();  // == tabB..getRowCount();
    for (i = 0; i < nLins; i++) {
      for (j = 0; j < nCols; j++) {
      	res = 0;
      	for (k = 0; k < nInner; k++) {
        	v1 = ((Double)tabA.getValueAt(i, k)).doubleValue();
        	v2 = ((Double)tabB.getValueAt(k, j)).doubleValue();
        	res +=  v1 * v2;
        	tabC.setValueAt(new Double(res), i, j);
      	}
      }
    }   		
	}
	/*
	 *	Le o arquivo passado como argumento e retorna a matriz.
	 */
	public double[][] LerArquivo(File arquivo) throws IOException {
    	BufferedReader temp = null;
    	String linha;
    	StringTokenizer token;
    	int nLins, nCols;
    	double[][] tMatriz, tOk;
    	tOk = new double[1][1];
    	try {
      		temp = new BufferedReader(new FileReader(arquivo.getName()));
      		linha = temp.readLine();
      		token = new StringTokenizer(linha);
      		nLins = Integer.parseInt(token.nextToken());
      		nCols = Integer.parseInt(token.nextToken());
      		tMatriz = new double[nLins][nCols];
      		for (int i = 0; i < nLins; ++i) {
        		linha = temp.readLine();
        		token = new StringTokenizer(linha);
        		for (int j = 0; j < nCols; ++j) {
          			tMatriz[i][j] = (new Double(token.nextToken())).doubleValue();
        		}
      		}
      		return tMatriz;
    	} catch(Exception E ) {
			   JOptionPane.showMessageDialog(null, "falhou");
    	} finally {
    		if (temp != null) 
        		try {
        			temp.close();
        		} catch(IOException e) {;}
		  }
   	 return tOk;
  	}
	/*
	 *	Salva o arquivo passado como argumento
	 */
	  public void SalvarArquivo(File arquivo, double[][] matrix) throws IOException {		
    	int nLins = matrix.length, nCols = matrix[0].length;
			PrintWriter dest = null;
			try{
				dest = new PrintWriter(new FileWriter(arquivo.getName()));
		    dest.println("" + nLins + "     " + nCols);				
		    dest.flush();
		    for( int i = 0; i < nLins; ++i ) {
		      for( int j = 0; j < nCols; ++j ) {
		      	dest.print(matrix[i][j] + ((j == nCols-1) ? "" : "  "));  
		      }
		      dest.println("");
		    }
		    dest.flush();
		    System.out.println(" " + arquivo.getName() + " has been saved !");
	 	 } catch( IOException e ) {
				throw new IOException();
			}
    }
  	/*
  	 *	Exibe a caixa de escolha e retorna o arquivo escolhido.
  	 */
  	public File ObtemArquivo() {
    	String caminho = ".";
    	int resposta;
    	JFileChooser seletor = new JFileChooser(caminho);
    	seletor.setFileSelectionMode(JFileChooser.FILES_ONLY);
    	resposta = seletor.showOpenDialog(this); 
	    if(resposta == JFileChooser.CANCEL_OPTION)
      		return null;
    	else
      		return seletor.getSelectedFile();
  	}
}