/*
  ==============================================================================

   This file is part of the JUCE library.
   Copyright (c) 2020 - Raw Material Software Limited

   JUCE is an open source library subject to commercial or open-source
   licensing.

   By using JUCE, you agree to the terms of both the JUCE 6 End-User License
   Agreement and JUCE Privacy Policy (both effective as of the 16th June 2020).

   End User License Agreement: www.juce.com/juce-6-licence
   Privacy Policy: www.juce.com/juce-privacy-policy

   Or: You may also use this code under the terms of the GPL v3 (see
   www.gnu.org/licenses).

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

//==============================================================================
/**
    A MouseListener can be registered with a component to receive callbacks
    about mouse events that happen to that component.

    @see Component::addMouseListener, Component::removeMouseListener

    @tags{GUI}
*/
class JUCE_API  MouseListener
{
public:
    /** Destructor. */
    virtual ~MouseListener() = default;

    /** Called when the mouse moves inside a component.

        If the mouse button isn't pressed and the mouse moves over a component,
        this will be called to let the component react to this.

        A component will always get a mouseEnter callback before a mouseMove.

        @param event details about the position and status of the mouse event, including
                     the source component in which it occurred
        @see mouseEnter, mouseExit, mouseDrag, contains
    */
    virtual void mouseMove (const MouseEvent& event);

    /** Called when the mouse first enters a component.

        If the mouse button isn't pressed and the mouse moves into a component,
        this will be called to let the component react to this.

        When the mouse button is pressed and held down while being moved in
        or out of a component, no mouseEnter or mouseExit callbacks are made - only
        mouseDrag messages are sent to the component that the mouse was originally
        clicked on, until the button is released.

        @param event details about the position and status of the mouse event, including
                     the source component in which it occurred
        @see mouseExit, mouseDrag, mouseMove, contains
    */
    virtual void mouseEnter (const MouseEvent& event);

    /** Called when the mouse moves out of a component.

        This will be called when the mouse moves off the edge of this
        component.

        If the mouse button was pressed, and it was then dragged off the
        edge of the component and released, then this callback will happen
        when the button is released, after the mouseUp callback.

        @param event  details about the position and status of the mouse event, including
                      the source component in which it occurred
        @see mouseEnter, mouseDrag, mouseMove, contains
    */
    virtual void mouseExit (const MouseEvent& event);

    /** Called when a mouse button is pressed.

        The MouseEvent object passed in contains lots of methods for finding out
        which button was pressed, as well as which modifier keys (e.g. shift, ctrl)
        were held down at the time.

        Once a button is held down, the mouseDrag method will be called when the
        mouse moves, until the button is released.

        @param event  details about the position and status of the mouse event, including
                      the source component in which it occurred
        @see mouseUp, mouseDrag, mouseDoubleClick, contains
    */
    virtual void mouseDown (const MouseEvent& event);

    /** Called when the mouse is moved while a button is held down.

        When a mouse button is pressed inside a component, that component
        receives mouseDrag callbacks each time the mouse moves, even if the
        mouse strays outside the component's bounds.

        @param event  details about the position and status of the mouse event, including
                      the source component in which it occurred
        @see mouseDown, mouseUp, mouseMove, contains, setDragRepeatInterval
    */
    virtual void mouseDrag (const MouseEvent& event);

    /** Called when a mouse button is released.

        A mouseUp callback is sent to the component in which a button was pressed
        even if the mouse is actually over a different component when the
        button is released.

        The MouseEvent object passed in contains lots of methods for finding out
        which buttons were down just before they were released.

        @param event  details about the position and status of the mouse event, including
                      the source component in which it occurred
        @see mouseDown, mouseDrag, mouseDoubleClick, contains
    */
    virtual void mouseUp (const MouseEvent& event);

    /** Called when a mouse button has been double-clicked on a component.

        The MouseEvent object passed in contains lots of methods for finding out
        which button was pressed, as well as which modifier keys (e.g. shift, ctrl)
        were held down at the time.

        @param event  details about the position and status of the mouse event, including
                      the source component in which it occurred
        @see mouseDown, mouseUp
    */
    virtual void mouseDoubleClick (const MouseEvent& event);

    /** Called when the mouse-wheel is moved.

        This callback is sent to the component that the mouse is over when the
        wheel is moved.

        If not overridden, a component will forward this message to its parent, so
        that parent components can collect mouse-wheel messages that happen to
        child components which aren't interested in them.

        @param event   details about the mouse event
        @param wheel   details about the wheel movement
    */
    virtual void mouseWheelMove (const MouseEvent& event,
                                 const MouseWheelDetails& wheel);

    /** Called when a pinch-to-zoom mouse-gesture is used.

        If not overridden, a component will forward this message to its parent, so
        that parent components can collect gesture messages that are unused by child
        components.

        @param event   details about the mouse event
        @param scaleFactor  a multiplier to indicate by how much the size of the target
                            should be changed. A value of 1.0 would indicate no change,
                            values greater than 1.0 mean it should be enlarged.
    */
    virtual void mouseMagnify (const MouseEvent& event, float scaleFactor);
};

} // namespace juce
