/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef BACKEND_EVENTS_SDL_H
#define BACKEND_EVENTS_SDL_H

#include "backends/platform/sdl/sdl-sys.h"
#include "backends/graphics/sdl/sdl-graphics.h"

#include "common/events.h"

// Type names which changed between SDL 1.2 and SDL 2.
#if !SDL_VERSION_ATLEAST(2, 0, 0)
typedef SDLKey     SDL_Keycode;
typedef SDLMod     SDL_Keymod;
typedef SDL_keysym SDL_Keysym;
#endif

/**
 * The SDL event source.
 */
class SdlEventSource : public Common::EventSource {
public:
	SdlEventSource();
	virtual ~SdlEventSource();

	void setGraphicsManager(SdlGraphicsManager *gMan) { _graphicsManager = gMan; }

	/**
	 * Gets and processes SDL events.
	 */
	virtual bool pollEvent(Common::Event &event);

	/**
	 * Emulates a mouse movement that would normally be caused by a mouse warp
	 * of the system mouse.
	 */
	void fakeWarpMouse(const int x, const int y);

	/** Returns whether a joystick is currently connected */
	bool isJoystickConnected() const;

	/** Sets whether a game is currently running */
	void setEngineRunning(bool value);

protected:
	/** Scroll lock state - since SDL doesn't track it */
	bool _scrollLock;

	bool _engineRunning;

	int _mouseX;
	int _mouseY;

	/** Joystick */
	SDL_Joystick *_joystick;

#if SDL_VERSION_ATLEAST(3, 0, 0)
	/** Game controller */
	SDL_Gamepad *_controller;
#elif SDL_VERSION_ATLEAST(2, 0, 0)
	/** Game controller */
	SDL_GameController *_controller;
#endif

	/** Last screen id for checking if it was modified */
	int _lastScreenID;

	/**
	 * The associated graphics manager.
	 */
	SdlGraphicsManager *_graphicsManager;

	/**
	 * Search for a game controller db file and load it.
	 */
	void loadGameControllerMappingFile();

	/**
	 * Open the SDL joystick with the specified index
	 *
	 * After this function completes successfully, SDL sends events for the device.
	 *
	 * If the joystick is also a SDL game controller, open it as a controller
	 * so an extended button mapping can be used.
	 */
	void openJoystick(int joystickIndex);

	/**
	 * Close the currently open joystick if any
	 */
	void closeJoystick();

	/**
	 * Pre process an event before it is dispatched.
	 */
	virtual void preprocessEvents(SDL_Event *event) {}

	/**
	 * Dispatchs SDL events for each handler.
	 */
	virtual bool dispatchSDLEvent(SDL_Event &ev, Common::Event &event);


	/** @name Event Handlers
	 * Handlers for specific SDL events, called by SdlEventSource::dispatchSDLEvent().
	 * This way, if a managers inherits fromt this SDL events manager, it can
	 * change the behavior of only a single event, without having to override all
	 * of SdlEventSource::dispatchSDLEvent().
	 */
	//@{

	virtual bool handleKeyDown(SDL_Event &ev, Common::Event &event);
	virtual bool handleKeyUp(SDL_Event &ev, Common::Event &event);
	virtual bool handleMouseMotion(SDL_Event &ev, Common::Event &event);
	virtual bool handleMouseButtonDown(SDL_Event &ev, Common::Event &event);
	virtual bool handleMouseButtonUp(SDL_Event &ev, Common::Event &event);
	virtual bool handleSysWMEvent(SDL_Event &ev, Common::Event &event);
	virtual int mapSDLJoystickButtonToOSystem(Uint8 sdlButton);
	virtual bool handleJoyButtonDown(SDL_Event &ev, Common::Event &event);
	virtual bool handleJoyButtonUp(SDL_Event &ev, Common::Event &event);
	virtual bool handleJoyAxisMotion(SDL_Event &ev, Common::Event &event);
	virtual bool handleJoyHatMotion(SDL_Event &ev, Common::Event &event);

#if SDL_VERSION_ATLEAST(2, 0, 0)
	virtual bool handleJoystickAdded(const SDL_JoyDeviceEvent &device, Common::Event &event);
	virtual bool handleJoystickRemoved(const SDL_JoyDeviceEvent &device, Common::Event &event);
	virtual int mapSDLControllerButtonToOSystem(Uint8 sdlButton);
	virtual bool handleControllerButton(const SDL_Event &ev, Common::Event &event, bool buttonUp);
	virtual bool handleControllerAxisMotion(const SDL_Event &ev, Common::Event &event);

	virtual bool isTouchPortTouchpadMode(SDL_TouchID port);
	virtual bool isTouchPortActive(SDL_TouchID port);
	virtual Common::Point getTouchscreenSize();
	virtual void convertTouchXYToGameXY(float touchX, float touchY, int *gameX, int *gameY);
#endif

	//@}

	/**
	 * Assigns the mouse coords to the mouse event. Furthermore notify the
	 * graphics manager about the position change.
	 * The parameters relx and rely for relative mouse movement
	 */
	virtual bool processMouseEvent(Common::Event &event, int x, int y, int relx = 0, int rely = 0);

	/**
	 * Remaps key events. This allows platforms to configure
	 * their custom keys.
	 */
	virtual bool remapKey(SDL_Event &ev, Common::Event &event);

	/**
	 * Maps the ASCII value of key
	 */
	virtual int mapKey(SDL_Keycode key, SDL_Keymod mod, Uint16 unicode);

	/**
	 * Configures the key modifiers flags status
	 */
	virtual void SDLModToOSystemKeyFlags(SDL_Keymod mod, Common::Event &event);

	/**
	 * Translates SDL key codes to OSystem key codes
	 */
	Common::KeyCode SDLToOSystemKeycode(const SDL_Keycode key);

	/**
	 * Notify graphics manager of a resize request.
	 */
	bool handleResizeEvent(Common::Event &event, int w, int h);

	/**
	 * Extracts unicode information for the specific key.
	 * May only be used for key down events.
	 */
	uint32 obtainUnicode(const SDL_KeyboardEvent &key);

#if !SDL_VERSION_ATLEAST(3, 0, 0)
	/**
	 * Extracts the keycode for the specified key sym.
	 */
	SDL_Keycode obtainKeycode(const SDL_Keysym keySym);
#endif

	/**
	 * Whether _fakeMouseMove contains an event we need to send.
	 */
	bool _queuedFakeMouseMove;

	/**
	 * A fake mouse motion event sent when the graphics manager is told to warp
	 * the mouse but the system mouse is unable to be warped (e.g. because the
	 * window is not focused).
	 */
	Common::Event _fakeMouseMove;

	uint8 _lastHatPosition;

#if SDL_VERSION_ATLEAST(2, 0, 0)
	/**
	 * Whether _fakeKeyUp contains an event we need to send.
	 */
	bool _queuedFakeKeyUp;

	/**
	 * A fake key up event when we receive a TEXTINPUT without any previous
	 * KEYDOWN event.
	 */
	Common::Event _fakeKeyUp;

	enum {
		MAX_NUM_FINGERS = 3, // number of fingers to track per panel
		MAX_TAP_TIME = 250, // taps longer than this will not result in mouse click events
		MAX_TAP_MOTION_DISTANCE = 10, // max distance finger motion in Vita screen pixels to be considered a tap
		SIMULATED_CLICK_DURATION = 50, // time in ms how long simulated mouse clicks should be
		FINGER_SUBPIXEL_MULTIPLIER = 16 // multiplier for sub-pixel resolution
	};

	struct TouchFinger {
#if SDL_VERSION_ATLEAST(3, 0, 0)
		SDL_FingerID id = 0; // 0: no touch
#else 
		int id = -1; // -1: no touch
#endif
		uint32 timeLastDown = 0;
		int lastX = 0; // last known screen coordinates
		int lastY = 0; // last known screen coordinates
		float lastDownX = 0; // SDL touch coordinates when last pressed down
		float lastDownY = 0; // SDL touch coordinates when last pressed down
	};

	enum DraggingType {
		DRAG_NONE = 0,
		DRAG_TWO_FINGER,
		DRAG_THREE_FINGER,
	};

	struct TouchPanelState {
		TouchFinger _finger[MAX_NUM_FINGERS]; // keep track of finger status
		DraggingType _multiFingerDragging = DRAG_NONE; // keep track whether we are currently drag-and-dropping
		unsigned int _simulatedClickStartTime[2] = {0, 0}; // initiation time of last simulated left or right click (zero if no click)
		int _hiresDX = 0; // keep track of slow, sub-pixel, finger motion across multiple frames
		int _hiresDY = 0;
		bool _tapMade = false;
	};

	Common::HashMap<unsigned long, TouchPanelState> _touchPanels;

private:
	void preprocessFingerDown(SDL_Event *event);
	bool preprocessFingerUp(SDL_Event *event, Common::Event *ev);
	void preprocessFingerMotion(SDL_Event *event);
	void finishSimulatedMouseClicks(void);
#endif
};

#endif