// Copyright (c) 2016-2018 Kiwano - Nomango
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

#pragma once
#include <array>
#include <kiwano/core/Common.h>
#include <kiwano/base/Module.h>
#include <kiwano/core/Keys.h>
#include <kiwano/event/Event.h>
#include <kiwano/macros.h>
#include <kiwano/math/Math.h>

namespace kiwano
{
/**
 * \~chinese
 * @brief 输入设备实例，可获取鼠标和键盘的按键状态
 */
class KGE_API Input final
    : public Singleton<Input>
    , public Module
{
    friend Singleton<Input>;

public:
    /**
     * \~chinese
     * @brief 检测键盘按键是否正被按下
     * @param key 键值
     */
    bool IsDown(KeyCode key) const;

    /**
     * \~chinese
     * @brief 检测键盘按键是否刚被点击
     * @param key 键值
     */
    bool WasPressed(KeyCode key) const;

    /**
     * \~chinese
     * @brief 检测键盘按键是否刚抬起
     * @param key 键值
     */
    bool WasReleased(KeyCode key) const;
    /**
     * \~chinese
     * @brief 检测鼠标按键是否正被按下
     * @param btn 鼠标键值
     */
    bool IsDown(MouseButton btn) const;

    /**
     * \~chinese
     * @brief 检测鼠标按键是否刚被点击
     * @param btn 鼠标键值
     */
    bool WasPressed(MouseButton btn) const;

    /**
     * \~chinese
     * @brief 检测鼠标按键是否刚抬起
     * @param btn 鼠标键值
     */
    bool WasReleased(MouseButton btn) const;

    /**
     * \~chinese
     * @brief 获得鼠标 x 坐标
     * @return 鼠标 x 坐标
     */
    float GetMouseX() const;

    /**
     * \~chinese
     * @brief 获得鼠标 y 坐标
     * @return 鼠标 y 坐标
     */
    float GetMouseY() const;

    /**
     * \~chinese
     * @brief 获得鼠标坐标
     * @return 鼠标坐标
     */
    Point GetMousePos() const;

public:
    void OnUpdate(UpdateModuleContext& ctx) override;

    void HandleEvent(EventModuleContext& ctx) override;

    ~Input();

private:
    Input();

    void UpdateKey(KeyCode key, bool down);

    void UpdateButton(MouseButton btn, bool down);

    void UpdateMousePos(const Point& pos);

private:
    static const int KEY_NUM    = int(KeyCode::Last);
    static const int BUTTON_NUM = int(MouseButton::Last);

    bool  want_update_keys_;
    bool  want_update_buttons_;
    Point mouse_pos_;

    enum KeyIndex : size_t
    {
        Current = 0,
        Prev
    };

    std::array<bool, BUTTON_NUM> buttons_[2];
    std::array<bool, KEY_NUM>    keys_[2];
};
}  // namespace kiwano