package org.eclipse.debug.ui;

/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */

import org.eclipse.debug.core.ILaunch;
import org.eclipse.debug.core.ILaunchConfiguration;
import org.eclipse.debug.core.ILaunchConfigurationWorkingCopy;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
 
/**
 * A launch configuration tab is used to edit/view attributes
 * of a specific type of launch configuration. Launch
 * configurations are presented in a dialog, with a tab folder.
 * Each tab manipulates one ore more attributes of a launch
 * configuration. 
 * <p>
 * The tab's lifecycle begins when <code>setLaunchConfigurationDialog(ILaunchConfigurationDialog)</code>
 * is called. A tab may then be asked repeatedly to initialize its
 * controls to display values for a launch configuration (see
 * <code>initializeFrom(ILaunchConfiguration)</code>), and to
 * apply its current settings to a launch configuration (see
 * <code>performApply(ILaunchConfigurationWorkingCopy)</code>).
 * While a user manipulates a tab's controls, the tab is not
 * intended to update a launch configuration. Updating a launch
 * configuration should only be performed when <code>performApply</code>
 * is called. To end a tab's lifecyle, <code>dispose()</code> will
 * be called. Note that a tab can be disposed before its control
 * has been created.
 * </p>
 * <p>
 * To support single-click launching, tabs are required to initialize
 * default values into launch configurations (possibly when their controls
 * have not been created). See <code>setDefault(ILaunchConfigurationWorkingCopy)</code>.
 * As well, the method <code>launched</code> can be called when the tab's
 * control does not exist.
 * </p>
 * <p>
 * This interface is intended to be implemented by clients.
 * </p>
 * @see org.eclipse.debug.core.ILaunchConfigurationType
 * @see org.eclipse.debug.core.ILaunchConfiguration
 * @since 2.0
 */
public interface ILaunchConfigurationTab {

	/**
	 * Creates the top level control for this launch configuration
	 * tab under the given parent composite.  This method is called once on
	 * tab creation, after <code>setLaunchConfigurationDialog</code>
	 * is called.
	 * <p>
	 * Implementors are responsible for ensuring that
	 * the created control can be accessed via <code>getControl</code>
	 * </p>
	 *
	 * @param parent the parent composite
	 */
	public void createControl(Composite parent);
	
	/**
	 * Returns the top level control for this tab.
	 * <p>
	 * May return <code>null</code> if the control
	 * has not been created yet.
	 * </p>
	 *
	 * @return the top level control or <code>null</code>
	 */
	public Control getControl();	
	
	/**
	 * Initializes the given launch configuration with
	 * default values for this tab. This method
	 * is called when a new launch configuration is created
	 * such that the configuration can be initialized with
	 * meaningful values. This method may be called before this
	 * tab's control is created, to support single-click launching.
	 * 
	 * @param configuration launch configuration
	 */
	public void setDefaults(ILaunchConfigurationWorkingCopy configuration);	
	
	/**
	 * Initializes this tab's controls with values from the given
	 * launch configuration. This method is called when
	 * a configuration is selected to view or edit, after this
	 * tab's control has been created.
	 * 
	 * @param configuration launch configuration
	 */
	public void initializeFrom(ILaunchConfiguration configuration);		
	
	/**
	 * Notifies this launch configuration tab that it has
	 * been disposed. Marks the end of this tab's lifecycle,
	 * allowing this tab to perform any cleanup required.
	 */
	public void dispose();
	
	/**
	 * Copies values from this tab into the given 
	 * launch configuration.
	 * 
	 * @param configuration launch configuration
	 */
	public void performApply(ILaunchConfigurationWorkingCopy configuration);
	
	/**
	 * Returns the current error message for this tab.
	 * May be <code>null</code> to indicate no error message.
	 * <p>
	 * An error message should describe some error state,
	 * as opposed to a message which may simply provide instruction
	 * or information to the user.
	 * </p>
	 * 
	 * @return the error message, or <code>null</code> if none
	 */
	public String getErrorMessage();
	
	/**
	 * Returns the current message for this tab.
	 * <p>
	 * A message provides instruction or information to the 
	 * user, as opposed to an error message which should 
	 * describe some error state.
	 * </p>
	 * 
	 * @return the message, or <code>null</code> if none
	 */
	public String getMessage();	
	
	/**
	 * Returns whether this tab is in a valid state in the context of the specified launch configuration.
	 * <p>
	 * This information is typically used by the launch configuration
	 * dialog to decide when it is okay to launch.
	 * </p>
	 *
	 * @param launchConfig launch configuration which provides context for validating this tab.
	 *         This value must not be <code>null</code>.
	 *
	 * @return whether this tab is in a valid state
	 */
	public boolean isValid(ILaunchConfiguration launchConfig);
	
	/**
	 * Returns whether this tab is in a state that allows the launch configuration whose values
	 * this tab is showing to be saved.  This differs from <code>isValid()</code> in that <code>canSave()</code>
	 * determines if this tab prevents the current launch configuration from being saved, whereas
	 * <code>isValid()</code> determines if this tab prevents the current launch configuration from
	 * being launched.
	 * 
	 * <p>
	 * This information is typically used by the launch configuration
	 * dialog to decide when it is okay to save a launch configuration.
	 * </p>
	 * 
	 * @return whether this tab is in a state that allows the current launch configuration to be saved
	 */
	public boolean canSave();
	
	/**
	 * Sets the launch configuration dialog that hosts this tab.
	 * This is the first method called on a launch configuration
	 * tab, and marks the beginning of this tab's lifecycle.
	 * 
	 * @param dialog launch configuration dialog
	 */
	public void setLaunchConfigurationDialog(ILaunchConfigurationDialog dialog);
	
	/**
	 * Notifies this tab that the specified configuration has been
	 * launched, resulting in the given launch. This method can be
	 * called when a tab's control does not exist, to support single-click
	 * launching.
	 * 
	 * @param launch the result of launching the current
	 *  launch configuration
	 */
	public void launched(ILaunch launch);
	
	/**
	 * Returns the name of this tab.
	 * 
	 * @return the name of this tab
	 */
	public String getName();
	
	/**
	 * Returns the image for this tab, or <code>null</code> if none
	 * 
	 * @return the image for this tab, or <code>null</code> if none
	 */
	public Image getImage();	
}