#include "InputSystem.h"
#include <Windows.h>

InputSystem::InputSystem()
{
}

InputSystem::~InputSystem()
{
}

void InputSystem::update()
{
    POINT current_mouse_pos = {};
    ::GetCursorPos(&current_mouse_pos);

    if (m_first_time)
    {
        m_old_mouse_pos = Point(current_mouse_pos.x, current_mouse_pos.y);
        m_first_time = false;
    }

    if (current_mouse_pos.x != m_old_mouse_pos.m_x || current_mouse_pos.y != m_old_mouse_pos.m_y)
    {
        //THERE IS MOUSE MOVE EVENT
        std::unordered_set<InputListener*>::iterator it = m_set_listeners.begin();

        while (it != m_set_listeners.end())
        {
            (*it)->onMouseMove(Point(current_mouse_pos.x - m_old_mouse_pos.m_x, current_mouse_pos.y - m_old_mouse_pos.m_y));
            ++it;
        }
    }
    m_old_mouse_pos = Point(current_mouse_pos.x, current_mouse_pos.y);

    if (::GetKeyboardState(m_keys_state))
    {
        for (unsigned int i = 0; i < 256; i++)
        {
            // KEY IS DOWN
            if (m_keys_state[i] & 0x80)
            {
                std::unordered_set<InputListener*>::iterator it = m_set_listeners.begin();

                while (it != m_set_listeners.end())
                {
                    if (i == VK_LBUTTON)
                    {
                        if (m_keys_state[i] != m_old_keys_state[i])
                            (*it)->onLeftMouseDown(Point(current_mouse_pos.x, current_mouse_pos.y));
                    }
                    else if (i == VK_RBUTTON)
                    {
                        if (m_keys_state[i] != m_old_keys_state[i])
                            (*it)->onRightMouseDown(Point(current_mouse_pos.x, current_mouse_pos.y));
                    }
                    else
                        (*it)->onKeyDown(i);

                    ++it;
                }
            }
            else // KEY IS UP
            {
                if (m_keys_state[i] != m_old_keys_state[i])
                {
                    std::unordered_set<InputListener*>::iterator it = m_set_listeners.begin();

                    while (it != m_set_listeners.end())
                    {
                        if (i == VK_LBUTTON)
                            (*it)->onLeftMouseUp(Point(current_mouse_pos.x, current_mouse_pos.y));
                        else if (i == VK_RBUTTON)
                            (*it)->onRightMouseUp(Point(current_mouse_pos.x, current_mouse_pos.y));
                        else
                            (*it)->onKeyUp(i);

                        ++it;
                    }
                }

            }

        }
        // store current keys state to old keys state buffer
        ::memcpy(m_old_keys_state, m_keys_state, sizeof(unsigned char) * 256);
    }
}

void InputSystem::addListener(InputListener * listener)
{
    m_set_listeners.insert(listener);
}

void InputSystem::removeListener(InputListener * listener)
{
    m_set_listeners.erase(listener);
}

InputSystem * InputSystem::get()
{
    static InputSystem system;
    return &system;
}