import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Font;
import java.awt.ScrollPane;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;
import javax.swing.SwingConstants;
import javax.swing.border.LineBorder;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumn;

/** UI class
*
* User interface to collect data and search.
*
* Uses swing
*
*/

public class UI extends JFrame {

	//input panel
	private JPanel inputPane;
	private JTextField nameTextField;
	private JTextField priceTextField;
	private JButton enterDataButton;

	// output panel
	private JPanel contentPane;
	private JTable searchTable;
	private JButton displayButton;

	// search function
	private JTextField searchTextField;
	private JButton searchButton;
	private JTextField matchTextField;

	// data collection
	private GroceryList gl;

/** UI - manages interaction with user
 *
 * Collects data when button is pressed and stores data in array
 * Displays all data collected in text area
 * Searches for matching name and displays associated data
 */
	public UI() {
		// Add title to window
		super("Grocery List Management System");

		// Initialize data structure
		gl = new GroceryList();

		setResizable(false);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 600, 450);

		contentPane = new JPanel();
		contentPane.setBorder(new LineBorder(new Color(112, 12, 102), 4, true));
		setContentPane(contentPane);
		contentPane.setLayout(null);

		// Default font for the user interface
		Font defaultFont = new Font("Arial", Font.PLAIN, 12);

		// Input related fields for add/updating a GrocItem
		inputPane = new JPanel();
		inputPane.setBorder(new LineBorder(new Color(112, 12, 102), 1, true));
		inputPane.setBounds(10, 32, 574, 125);
		contentPane.add(inputPane);
		inputPane.setLayout(null);

		// labels for input fields
		JLabel lblFoodName = new JLabel("Name");
		lblFoodName.setFont(defaultFont);
		lblFoodName.setHorizontalAlignment(SwingConstants.RIGHT);
		lblFoodName.setBounds(16, 11, 60, 14);
		inputPane.add(lblFoodName);

		JLabel lblPrice = new JLabel("Price");
		lblPrice.setFont(defaultFont);
		lblPrice.setHorizontalAlignment(SwingConstants.RIGHT);
		lblPrice.setBounds(16, 36, 60, 14);
		inputPane.add(lblPrice);

		// input field for name of grocery item
		nameTextField = new JTextField();
		nameTextField.setFont(defaultFont);
		nameTextField.setBounds(80, 8, 220, 20);
		inputPane.add(nameTextField);
		nameTextField.setColumns(25);

		// input field for price
		priceTextField = new JTextField();
		priceTextField.setFont(defaultFont);
		priceTextField.setBounds(80, 33, 220, 20);
		inputPane.add(priceTextField);
		priceTextField.setColumns(15);

		enterDataButton = new JButton("Add");
		// Event trigger for the Add button click
		enterDataButton.addMouseListener(new MouseAdapter() {
			public void mouseClicked(MouseEvent e) {
				addGrocItemToList();
			}
		});
		enterDataButton.setFont(defaultFont);
		enterDataButton.setBounds(360, 11, 90, 28);
		inputPane.add(enterDataButton);

		// Search function

		// label for search field
		JLabel lblSearchFoodName = new JLabel("Name");
		lblSearchFoodName.setFont(defaultFont);
		lblSearchFoodName.setHorizontalAlignment(SwingConstants.RIGHT);
		lblSearchFoodName.setBounds(16, 71, 60, 14);
		inputPane.add(lblSearchFoodName);

		// input field for name of grocery item to match
		searchTextField = new JTextField();
		searchTextField.setFont(defaultFont);
		searchTextField.setBounds(80, 71, 220, 20);
		inputPane.add(searchTextField);
		searchTextField.setColumns(25);
		inputPane.add(searchTextField);

		JLabel lblDisplayPrice = new JLabel("Price");
		lblDisplayPrice.setFont(defaultFont);
		lblDisplayPrice.setHorizontalAlignment(SwingConstants.RIGHT);
		lblDisplayPrice.setBounds(16, 96, 60, 14);
		inputPane.add(lblDisplayPrice);

		// display field for matching data
		matchTextField = new JTextField();
		matchTextField.setFont(defaultFont);
		matchTextField.setBounds(80, 96, 220, 20);
		matchTextField.setEditable(false);				// display matching data
		inputPane.add(matchTextField);
		searchTextField.setColumns(25);

		searchButton = new JButton("Search");
		// Event trigger for the Search button click
		searchButton.addMouseListener(new MouseAdapter() {
			public void mouseClicked(MouseEvent e) {
				matchTextField.setText (searchForGrocItem(searchTextField.getText()));
			}
		});
		searchButton.setFont(defaultFont);
		searchButton.setBounds(360, 71, 90, 28);
		inputPane.add(searchButton);

		// output
		JScrollPane scrollPane = new JScrollPane();
		scrollPane.setBounds(10, 208, 574, 203);
		contentPane.add(scrollPane);

		// output table
		searchTable = new JTable();
		searchTable.setFont(defaultFont);
		searchTable.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
		// Set the model of the search results table that defines the layout of the data
		searchTable.setModel(new DefaultTableModel(new String[] {"Name", "Price"}, 0) {
			boolean[] columnEditables = new boolean[] {
				false, false
			};
			public boolean isCellEditable(int row, int column) {
				return columnEditables[column];
			}
		});
		searchTable.getTableHeader().setFont(defaultFont);

		// display grocery list on button click
		displayButton = new JButton("Display");
		displayButton.addMouseListener(new MouseAdapter() {
			// Event trigger for the search button click
			public void mouseClicked(MouseEvent e) {
				displayList();
			}
		});
		displayButton.setFont(defaultFont);
		displayButton.setBounds(370, 168, 90, 28);
		contentPane.add(displayButton);
		scrollPane.setViewportView(searchTable);

		setLocationRelativeTo(null);
		setVisible(true);
	}

	/** displayList()
	 *
	 * Clears display table before retrieving and displaying collection of grocery items
	 *
	 */
	public void displayList()	{
		// Clear the search results table
		DefaultTableModel model = (DefaultTableModel)searchTable.getModel();
		for(int i = model.getRowCount() - 1; i >= 0; i--)
			model.removeRow(i);

		// add grocery items to display table, one by one
		GrocItem [] list = gl.getList();
		for(int i = 0; i < gl.listSize(); i++)	{
			model.addRow(new Object[] {
				list[i].getName(),
				list[i].getPrice()
			});
		}
	}

	/** addGrocItemToList ()
	 *
	 * Collects data from UI, instantiates a new GrocItem and adds it to the grocery list
	 */
	public void addGrocItemToList ()	{
		gl.add( new GrocItem (nameTextField.getText(), Double.parseDouble (priceTextField.getText())));

		// reset input fields to empty
		nameTextField.setText("");
		priceTextField.setText("");

	}

	/** searchForGrocItem (String n)
	 *
	 * @param 	n		Name of grocery item to find
	 * @return 	String	matching price information
	 */
	public String searchForGrocItem (String name)	{
		GrocItem gi = gl.searchForGrocItem (name);

		// display matching price, if matching item found
		if (gi==null)
			return "Not found";
		else
			return (Double.toString (gi.getPrice()));
	}
}