#ifndef Magnum_Platform_NaClApplication_h
#define Magnum_Platform_NaClApplication_h
/*
    Copyright © 2010, 2011, 2012 Vladimír Vondruš <mosra@centrum.cz>

    This file is part of Magnum.

    Magnum is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License version 3
    only, as published by the Free Software Foundation.

    Magnum is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    GNU Lesser General Public License version 3 for more details.
*/

/** @file
 * @brief Class Magnum::Platform::NaClApplication
 */

#include <string>
#include <Containers/EnumSet.h>
#include <ppapi/cpp/input_event.h>
#include <ppapi/cpp/instance.h>
#include <ppapi/cpp/module.h>
#include <ppapi/cpp/mouse_lock.h>
#include <ppapi/cpp/graphics_3d_client.h>
#include <ppapi/gles2/gl2ext_ppapi.h>

#include "Math/Vector2.h"
#include "Magnum.h"

#include "magnumCompatibility.h"

namespace pp {
    class Graphics3D;
    class Fullscreen;
}

namespace Magnum { namespace Platform {

/** @nosubgrouping
@brief NaCl application

Application running in [Google Chrome Native Client](https://developers.google.com/native-client/).
Supports keyboard and mouse handling.

@section NaClApplication-usage Usage

You need to implement at least drawEvent() and viewportEvent() to be able to
draw on the screen. The subclass must be then registered to NaCl API using
MAGNUM_NACLAPPLICATION_MAIN() macro.
@code
class MyApplication: public Magnum::Platform::Sdl2Application {
    // implement required methods...
};
MAGNUM_NACLAPPLICATION_MAIN(MyApplication)
@endcode
*/
class NaClApplication: public pp::Instance, public pp::Graphics3DClient, public pp::MouseLock {
    public:
        class InputEvent;
        class KeyEvent;
        class MouseEvent;
        class MouseMoveEvent;

        /**
         * @brief Constructor
         * @param instance  Module instance
         * @param size      Rendering size
         *
         * Creates double-buffered RGBA canvas with depth and stencil buffers.
         */
        explicit NaClApplication(PP_Instance instance, const Math::Vector2<GLsizei>& size = Math::Vector2<GLsizei>(640, 480));

        ~NaClApplication();

        /** @brief Whether the application runs fullscreen */
        bool isFullscreen();

        /**
         * @brief Set fullscreen
         * @return `False` if switch to opposite mode is in progress or if the
         *      switch is not possible, `true` otherwise.
         *
         * The switch is done asynchronously, during the switch no event
         * processing is done.
         */
        bool setFullscreen(bool enabled);

    protected:

        /** @{ @name Drawing functions */

        /** @copydoc GlutApplication::viewportEvent() */
        virtual void viewportEvent(const Math::Vector2<GLsizei>& size) = 0;

        /** @copydoc GlutApplication::drawEvent() */
        virtual void drawEvent() = 0;

        /** @copydoc GlutApplication::swapBuffers() */
        void swapBuffers();

        /** @copydoc GlutApplication::redraw() */
        inline void redraw() { flags |= Flag::Redraw; }

        /*@}*/

        /** @{ @name Keyboard handling */

        /**
         * @brief Key press event
         *
         * Called when an key is pressed. Default implementation does nothing.
         * If you accept the event, call @ref InputEvent::setAccepted() "setAccepted()"
         * on it, otherwise the event will be propagated to the browser.
         */
        virtual void keyPressEvent(KeyEvent& event);

        /**
         * @brief Key release event
         *
         * Called when an key is released. Default implementation does nothing.
         * If you accept the event, call @ref InputEvent::setAccepted() "setAccepted()"
         * on it, otherwise the event will be propagated to the browser.
         */
        virtual void keyReleaseEvent(KeyEvent& event);

        /*@}*/

        /** @{ @name Mouse handling */

    public:
        /** @brief Whether mouse is locked */
        inline bool isMouseLocked() const {
            return flags & Flag::MouseLocked;
        }

        /**
         * @brief Enable or disable mouse locking
         *
         * When mouse is locked, the cursor is hidden and only
         * MouseMoveEvent::relativePosition() is changing, absolute position
         * stays the same.
         */
        void setMouseLocked(bool enabled);

    protected:
        /**
         * @brief Mouse press event
         *
         * Called when mouse button is pressed. Default implementation does
         * nothing. If you accept the event, call @ref InputEvent::setAccepted() "setAccepted()"
         * on it, otherwise the event will be propagated to the browser.
         */
        virtual void mousePressEvent(MouseEvent& event);

        /**
         * @brief Mouse release event
         *
         * Called when mouse button is released. Default implementation does
         * nothing. If you accept the event, call @ref InputEvent::setAccepted() "setAccepted()"
         * on it, otherwise the event will be propagated to the browser.
         */
        virtual void mouseReleaseEvent(MouseEvent& event);

        /**
         * @brief Mouse move event
         *
         * Called when mouse is moved. Default implementation does nothing. If
         * you accept the event, call @ref InputEvent::setAccepted() "setAccepted()"
         * on it, otherwise the event will be propagated to the browser.
         */
        virtual void mouseMoveEvent(MouseMoveEvent& event);

        /*@}*/

    private:
        enum class Flag: std::uint8_t {
            ViewportUpdated = 1 << 0,
            SwapInProgress = 1 << 1,
            Redraw = 1 << 2,
            FullscreenSwitchInProgress = 1 << 3,
            WillBeFullscreen = 1 << 4,
            MouseLocked = 1 << 5
        };
        typedef Corrade::Containers::EnumSet<Flag, std::uint8_t> Flags;

        inline void Graphics3DContextLost() override {
            CORRADE_ASSERT(false, "NaClApplication: context unexpectedly lost", );
        }

        inline void MouseLockLost() override {
            flags &= ~Flag::MouseLocked;
        }

        void DidChangeView(const pp::View& view) override;

        bool HandleInputEvent(const pp::InputEvent& event) override;

        static void swapCallback(void* applicationInstance, std::int32_t);
        static void mouseLockCallback(void* applicationInstance, std::int32_t);

        pp::Graphics3D* graphics;
        pp::Fullscreen* fullscreen;
        Context* c;
        Math::Vector2<GLsizei> viewportSize;
        Flags flags;

        CORRADE_ENUMSET_FRIEND_OPERATORS(Flags)
};

/**
@brief Base for input events

If you accept the event, call setAccepted(), otherwise the event will be
propagated to the browser.
@see KeyEvent, MouseEvent, MouseMoveEvent, keyPressEvent(), keyReleaseEvent(),
    mousePressEvent(), mouseReleaseEvent(), mouseMoveEvent()
*/
class NaClApplication::InputEvent {
    InputEvent(const InputEvent& other) = delete;
    InputEvent(InputEvent&& other) = delete;
    InputEvent& operator=(const InputEvent& other) = delete;
    InputEvent& operator=(InputEvent&& other) = delete;

    public:
        /**
         * @brief %Modifier
         *
         * @todo AltGr + PP_INPUTEVENT_MODIFIER_ISKEYPAD, PP_INPUTEVENT_MODIFIER_ISAUTOREPEAT
         * @see Modifiers, modifiers()
         */
        enum class Modifier: std::uint32_t {
            Shift = PP_INPUTEVENT_MODIFIER_SHIFTKEY,    /**< Shift */
            Ctrl = PP_INPUTEVENT_MODIFIER_CONTROLKEY,   /**< Ctrl */
            Alt = PP_INPUTEVENT_MODIFIER_ALTKEY,        /**< Alt */
            Meta = PP_INPUTEVENT_MODIFIER_METAKEY,      /**< Meta */

            LeftButton = PP_INPUTEVENT_MODIFIER_LEFTBUTTONDOWN,     /**< Left mouse button */
            MiddleButton = PP_INPUTEVENT_MODIFIER_MIDDLEBUTTONDOWN, /**< Middle mouse button */
            RightButton = PP_INPUTEVENT_MODIFIER_RIGHTBUTTONDOWN,   /**< Right mouse button */

            CapsLock = PP_INPUTEVENT_MODIFIER_CAPSLOCKKEY,  /**< Caps lock */
            NumLock = PP_INPUTEVENT_MODIFIER_NUMLOCKKEY     /**< Num lock */
        };

        /**
         * @brief Set of modifiers
         *
         * @see modifiers()
         */
        typedef Corrade::Containers::EnumSet<Modifier, std::uint32_t> Modifiers;

        inline virtual ~InputEvent() {}

        /** @brief Modifiers */
        inline Modifiers modifiers() const { return _modifiers; }

        /**
         * @brief Set event as accepted
         *
         * If the event is ignored (i.e., not set as accepted), it is
         * propagated to the browser. By default is each event ignored.
         */
        inline void setAccepted(bool accepted = true) { _accepted = accepted; }

        /** @brief Whether the event is accepted */
        inline bool isAccepted() { return _accepted; }

    #ifndef DOXYGEN_GENERATING_OUTPUT
    protected:
        inline InputEvent(Modifiers modifiers): _accepted(false), _modifiers(modifiers) {}
    #endif

    private:
        bool _accepted;
        const Modifiers _modifiers;
};

/**
@brief Key event

See InputEvent for more information.
@see keyPressEvent(), keyReleaseEvent()
*/
class NaClApplication::KeyEvent: public NaClApplication::InputEvent {
    friend class NaClApplication;

    public:
        /**
         * @brief Key
         *
         * @todo Slash, percent, equal to be compatible with *XApplication
         * @see key()
         */
        enum class Key: std::uint32_t {
            Enter = 0x0D,               /**< Enter */
            Esc = 0x1B,                 /**< Escape */

            Up = 0x26,                  /**< Up arrow */
            Down = 0x28,                /**< Down arrow */
            Left = 0x25,                /**< Left arrow */
            Right = 0x27,               /**< Right arrow */
            F1 = 0x70,                  /**< F1 */
            F2 = 0x71,                  /**< F2 */
            F3 = 0x72,                  /**< F3 */
            F4 = 0x73,                  /**< F4 */
            F5 = 0x74,                  /**< F5 */
            F6 = 0x75,                  /**< F6 */
            F7 = 0x76,                  /**< F7 */
            F8 = 0x77,                  /**< F8 */
            F9 = 0x78,                  /**< F9 */
            F10 = 0x79,                 /**< F10 */
            F11 = 0x7A,                 /**< F11 */
            F12 = 0x7B,                 /**< F12 */
            Home = 0x24,                /**< Home */
            End = 0x23,                 /**< End */
            PageUp = 0x21,              /**< Page up */
            PageDown = 0x22,            /**< Page down */

            Space = 0x20,               /**< Space */
            Comma = 0xBC,               /**< Comma */
            Period = 0xBE,              /**< Period */
            Minus = 0xBD,               /**< Minus */
            Plus = 0xBB,                /**< Plus */

            Zero = '0',                 /**< Zero */
            One = '1',                  /**< One */
            Two = '2',                  /**< Two */
            Three = '3',                /**< Three */
            Four = '4',                 /**< Four */
            Five = '5',                 /**< Five */
            Six = '6',                  /**< Six */
            Seven = '7',                /**< Seven */
            Eight = '8',                /**< Eight */
            Nine = '9',                 /**< Nine */

            A = 'A',                    /**< Letter A */
            B = 'B',                    /**< Letter B */
            C = 'C',                    /**< Letter C */
            D = 'D',                    /**< Letter D */
            E = 'E',                    /**< Letter E */
            F = 'F',                    /**< Letter F */
            G = 'G',                    /**< Letter G */
            H = 'H',                    /**< Letter H */
            I = 'I',                    /**< Letter I */
            J = 'J',                    /**< Letter J */
            K = 'K',                    /**< Letter K */
            L = 'L',                    /**< Letter L */
            M = 'M',                    /**< Letter M */
            N = 'N',                    /**< Letter N */
            O = 'O',                    /**< Letter O */
            P = 'P',                    /**< Letter P */
            Q = 'Q',                    /**< Letter Q */
            R = 'R',                    /**< Letter R */
            S = 'S',                    /**< Letter S */
            T = 'T',                    /**< Letter T */
            U = 'U',                    /**< Letter U */
            V = 'V',                    /**< Letter V */
            W = 'W',                    /**< Letter W */
            X = 'X',                    /**< Letter X */
            Y = 'Y',                    /**< Letter Y */
            Z = 'Z'                     /**< Letter Z */
        };

        /** @brief Key */
        inline Key key() const { return _key; }

    private:
        inline KeyEvent(Key key, Modifiers modifiers): InputEvent(modifiers), _key(key) {}

        const Key _key;
};

/**
@brief Mouse event

See InputEvent for more information.
@see MouseMoveEvent, mousePressEvent(), mouseReleaseEvent()
*/
class NaClApplication::MouseEvent: public NaClApplication::InputEvent {
    friend class NaClApplication;

    public:
        /**
         * @brief Button
         *
         * @see button()
         */
        enum class Button: unsigned int {
            Left = PP_INPUTEVENT_MOUSEBUTTON_LEFT,      /**< Left button */
            Middle = PP_INPUTEVENT_MOUSEBUTTON_MIDDLE,  /**< Middle button */
            Right = PP_INPUTEVENT_MOUSEBUTTON_RIGHT     /**< Right button */
        };

        /** @brief Button */
        inline Button button() const { return _button; }

        /** @brief Position */
        inline Math::Vector2<int> position() const { return _position; }

    private:
        inline MouseEvent(Button button, const Math::Vector2<int>& position, Modifiers modifiers): InputEvent(modifiers), _button(button), _position(position) {}

        const Button _button;
        const Math::Vector2<int> _position;
};

/**
@brief Mouse move event

See InputEvent for more information.
@see MouseEvent, mouseMoveEvent()
*/
class NaClApplication::MouseMoveEvent: public NaClApplication::InputEvent {
    friend class NaClApplication;

    public:
        /** @brief Position */
        inline Math::Vector2<int> position() const { return _position; }

        /**
         * @brief Relative position
         *
         * Position relative to previous event.
         */
        inline Math::Vector2<int> relativePosition() const { return _relativePosition; }

    private:
        inline MouseMoveEvent(const Math::Vector2<int>& position, const Math::Vector2<int>& relativePosition, Modifiers modifiers): InputEvent(modifiers), _position(position), _relativePosition(relativePosition) {}

        const Math::Vector2<int> _position, _relativePosition;
};

CORRADE_ENUMSET_OPERATORS(NaClApplication::Flags)

#ifndef DOXYGEN_GENERATING_OUTPUT
namespace Implementation {
    template<class Application> class NaClModule: public pp::Module {
        public:
            inline ~NaClModule() {
                glTerminatePPAPI();
            }

            inline bool Init() override {
                return glInitializePPAPI(get_browser_interface()) == GL_TRUE;
            }

            inline pp::Instance* CreateInstance(PP_Instance instance) {
                return new Application(instance);
            }
    };
}
#endif

/** @hideinitializer
@brief Entry point for NaCl application
@param application  Application class name

See NaClApplication and @ref portability-applications for more information.
When no other application header is included this macro is also aliased to
`MAGNUM_APPLICATION_MAIN()`.
*/
/* look at that insane placement of __attribute__. WTF. */
#define MAGNUM_NACLAPPLICATION_MAIN(application)                            \
    namespace pp {                                                          \
        Module __attribute__ ((visibility ("default"))) * CreateModule() {  \
            return new Magnum::Platform::Implementation::NaClModule<application>(); \
        }                                                                   \
    }

#ifndef DOXYGEN_GENERATING_OUTPUT
#ifndef MAGNUM_APPLICATION_MAIN
#define MAGNUM_APPLICATION_MAIN(className) MAGNUM_NACLAPPLICATION_MAIN(className)
#else
#undef MAGNUM_APPLICATION_MAIN
#endif
#endif

CORRADE_ENUMSET_OPERATORS(NaClApplication::InputEvent::Modifiers)

/* Implementations for inline functions with unused parameters */
inline void NaClApplication::keyPressEvent(KeyEvent&) {}
inline void NaClApplication::keyReleaseEvent(KeyEvent&) {}
inline void NaClApplication::mousePressEvent(MouseEvent&) {}
inline void NaClApplication::mouseReleaseEvent(MouseEvent&) {}
inline void NaClApplication::mouseMoveEvent(MouseMoveEvent&) {}

}}

#endif