/* Copyright (c) 2013-2014 Jeffrey Pfau
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "InputController.h"

#include "ConfigController.h"
#include "GamepadAxisEvent.h"
#include "GamepadButtonEvent.h"

#include <QApplication>
#include <QTimer>
#include <QWidget>

extern "C" {
#include "util/configuration.h"
}

using namespace QGBA;

InputController::InputController(QObject* parent)
	: QObject(parent)
	, m_config(nullptr)
	, m_gamepadTimer(nullptr)
{
	GBAInputMapInit(&m_inputMap);

#ifdef BUILD_SDL
	m_sdlEvents.bindings = &m_inputMap;
	GBASDLInitEvents(&m_sdlEvents);
	GBASDLInitBindings(&m_inputMap);
	SDL_JoystickEventState(SDL_QUERY);

	m_gamepadTimer = new QTimer(this);
	connect(m_gamepadTimer, SIGNAL(timeout()), this, SLOT(testGamepad()));
	m_gamepadTimer->setInterval(50);
	m_gamepadTimer->start();
#endif

	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_X, GBA_KEY_A);
	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_Z, GBA_KEY_B);
	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_A, GBA_KEY_L);
	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_S, GBA_KEY_R);
	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_Return, GBA_KEY_START);
	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_Backspace, GBA_KEY_SELECT);
	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_Up, GBA_KEY_UP);
	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_Down, GBA_KEY_DOWN);
	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_Left, GBA_KEY_LEFT);
	GBAInputBindKey(&m_inputMap, KEYBOARD, Qt::Key_Right, GBA_KEY_RIGHT);
}

InputController::~InputController() {
	GBAInputMapDeinit(&m_inputMap);

#ifdef BUILD_SDL
	GBASDLDeinitEvents(&m_sdlEvents);
#endif
}

void InputController::setConfiguration(ConfigController* config) {
	m_config = config;
	loadConfiguration(KEYBOARD);
#ifdef BUILD_SDL
	loadConfiguration(SDL_BINDING_BUTTON);
#endif
}

void InputController::loadConfiguration(uint32_t type) {
	GBAInputMapLoad(&m_inputMap, type, m_config->configuration());
}

void InputController::saveConfiguration(uint32_t type) {
	GBAInputMapSave(&m_inputMap, type, m_config->configuration());
	m_config->write();
}

GBAKey InputController::mapKeyboard(int key) const {
	return GBAInputMapKey(&m_inputMap, KEYBOARD, key);
}

void InputController::bindKey(uint32_t type, int key, GBAKey gbaKey) {
	return GBAInputBindKey(&m_inputMap, type, key, gbaKey);
}

#ifdef BUILD_SDL
int InputController::testSDLEvents() {
	SDL_Joystick* joystick = m_sdlEvents.joystick;
	SDL_JoystickUpdate();
	int numButtons = SDL_JoystickNumButtons(joystick);
	int activeButtons = 0;
	int i;
	for (i = 0; i < numButtons; ++i) {
		GBAKey key = GBAInputMapKey(&m_inputMap, SDL_BINDING_BUTTON, i);
		if (key == GBA_KEY_NONE) {
			continue;
		}
		if (hasPendingEvent(key)) {
			continue;
		}
		if (SDL_JoystickGetButton(joystick, i)) {
			activeButtons |= 1 << key;
		}
	}
	int numHats = SDL_JoystickNumHats(joystick);
	for (i = 0; i < numHats; ++i) {
		int hat = SDL_JoystickGetHat(joystick, i);
		if (hat & SDL_HAT_UP) {
			activeButtons |= 1 << GBA_KEY_UP;
		}
		if (hat & SDL_HAT_LEFT) {
			activeButtons |= 1 << GBA_KEY_LEFT;
		}
		if (hat & SDL_HAT_DOWN) {
			activeButtons |= 1 << GBA_KEY_DOWN;
		}
		if (hat & SDL_HAT_RIGHT) {
			activeButtons |= 1 << GBA_KEY_RIGHT;
		}
	}

	int numAxes = SDL_JoystickNumAxes(joystick);
	for (i = 0; i < numAxes; ++i) {
		int value = SDL_JoystickGetAxis(joystick, i);

		enum GBAKey key = GBAInputMapAxis(&m_inputMap, SDL_BINDING_BUTTON, i, value);
		if (key != GBA_KEY_NONE) {
			activeButtons |= 1 << key;
		}
	}
	return activeButtons;
}

QSet<int> InputController::activeGamepadButtons() {
	SDL_Joystick* joystick = m_sdlEvents.joystick;
	SDL_JoystickUpdate();
	int numButtons = SDL_JoystickNumButtons(joystick);
	QSet<int> activeButtons;
	int i;
	for (i = 0; i < numButtons; ++i) {
		if (SDL_JoystickGetButton(joystick, i)) {
			activeButtons.insert(i);
		}
	}
	return activeButtons;
}

QSet<QPair<int, GamepadAxisEvent::Direction>> InputController::activeGamepadAxes() {
	SDL_Joystick* joystick = m_sdlEvents.joystick;
	SDL_JoystickUpdate();
	int numButtons = SDL_JoystickNumAxes(joystick);
	QSet<QPair<int, GamepadAxisEvent::Direction>> activeAxes;
	int i;
	for (i = 0; i < numButtons; ++i) {
		int32_t axis = SDL_JoystickGetAxis(joystick, i);
		if (axis >= AXIS_THRESHOLD || axis <= -AXIS_THRESHOLD) {
			activeAxes.insert(qMakePair(i, axis > 0 ? GamepadAxisEvent::POSITIVE : GamepadAxisEvent::NEGATIVE));
		}
	}
	return activeAxes;
}

void InputController::bindAxis(uint32_t type, int axis, GamepadAxisEvent::Direction direction, GBAKey key) {
	const GBAAxis* old = GBAInputQueryAxis(&m_inputMap, SDL_BINDING_BUTTON, axis);
	GBAAxis description = { GBA_KEY_NONE, GBA_KEY_NONE, -AXIS_THRESHOLD, AXIS_THRESHOLD };
	if (old) {
		description = *old;
	}
	switch (direction) {
	case GamepadAxisEvent::NEGATIVE:
		description.lowDirection = key;
		description.deadLow = -AXIS_THRESHOLD;
		break;
	case GamepadAxisEvent::POSITIVE:
		description.highDirection = key;
		description.deadHigh = AXIS_THRESHOLD;
		break;
	default:
		return;
	}
	GBAInputBindAxis(&m_inputMap, SDL_BINDING_BUTTON, axis, &description);
}
#endif

void InputController::testGamepad() {
#ifdef BUILD_SDL
	auto activeAxes = activeGamepadAxes();
	auto oldAxes = m_activeAxes;
	m_activeAxes = activeAxes;

	auto activeButtons = activeGamepadButtons();
	auto oldButtons = m_activeButtons;
	m_activeButtons = activeButtons;

	if (!QApplication::focusWidget()) {
		return;
	}

	activeAxes.subtract(oldAxes);
	oldAxes.subtract(m_activeAxes);

	for (auto& axis : m_activeAxes) {
		bool newlyAboveThreshold = activeAxes.contains(axis);
		GamepadAxisEvent* event = new GamepadAxisEvent(axis.first, axis.second, newlyAboveThreshold, this);
		if (newlyAboveThreshold) {
			postPendingEvent(event->gbaKey());
			if (!event->isAccepted()) {
				clearPendingEvent(event->gbaKey());
			}
		} else if (oldAxes.contains(axis)) {
			clearPendingEvent(event->gbaKey());
		}
		QApplication::sendEvent(QApplication::focusWidget(), event);
	}

	activeButtons.subtract(oldButtons);
	oldButtons.subtract(m_activeButtons);

	for (int button : activeButtons) {
		GamepadButtonEvent* event = new GamepadButtonEvent(GamepadButtonEvent::Down(), button, this);
		postPendingEvent(event->gbaKey());
		QApplication::sendEvent(QApplication::focusWidget(), event);
		if (!event->isAccepted()) {
			clearPendingEvent(event->gbaKey());
		}
	}
	for (int button : oldButtons) {
		GamepadButtonEvent* event = new GamepadButtonEvent(GamepadButtonEvent::Up(), button, this);
		clearPendingEvent(event->gbaKey());
		QApplication::sendEvent(QApplication::focusWidget(), event);
	}
#endif
}

void InputController::postPendingEvent(GBAKey key) {
	m_pendingEvents.insert(key);
}

void InputController::clearPendingEvent(GBAKey key) {
	m_pendingEvents.remove(key);
}

bool InputController::hasPendingEvent(GBAKey key) const {
	return m_pendingEvents.contains(key);
}