//========================================================================
// GLFW - An OpenGL library
// Platform:    Any
// API version: 3.0
// WWW:         http://www.glfw.org/
//------------------------------------------------------------------------
// Copyright (c) 2002-2006 Marcus Geelnard
// Copyright (c) 2006-2010 Camilla Berglund <elmindreda@elmindreda.org>
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
//    claim that you wrote the original software. If you use this software
//    in a product, an acknowledgment in the product documentation would
//    be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such, and must not
//    be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source
//    distribution.
//
//========================================================================

#include "internal.h"


//========================================================================
// Sets the cursor mode for the specified window
//========================================================================

static void setCursorMode(_GLFWwindow* window, int newMode)
{
    int oldMode, centerPosX, centerPosY;

    if (newMode != GLFW_CURSOR_NORMAL &&
        newMode != GLFW_CURSOR_HIDDEN &&
        newMode != GLFW_CURSOR_CAPTURED)
    {
        _glfwInputError(GLFW_INVALID_ENUM, NULL);
        return;
    }

    oldMode = window->cursorMode;
    if (oldMode == newMode)
        return;

    centerPosX = window->width / 2;
    centerPosY = window->height / 2;

    if (oldMode == GLFW_CURSOR_CAPTURED || newMode == GLFW_CURSOR_CAPTURED)
        _glfwPlatformSetCursorPos(window, centerPosX, centerPosY);

    _glfwPlatformSetCursorMode(window, newMode);
    window->cursorMode = newMode;

    if (oldMode == GLFW_CURSOR_CAPTURED)
        _glfwInputCursorMotion(window, window->cursorPosX, window->cursorPosY);
}


//========================================================================
// Set sticky keys mode for the specified window
//========================================================================

static void setStickyKeys(_GLFWwindow* window, int enabled)
{
    if (window->stickyKeys == enabled)
        return;

    if (!enabled)
    {
        int i;

        // Release all sticky keys
        for (i = 0;  i <= GLFW_KEY_LAST;  i++)
        {
            if (window->key[i] == GLFW_STICK)
                window->key[i] = GLFW_RELEASE;
        }
    }

    window->stickyKeys = enabled;
}


//========================================================================
// Set sticky mouse buttons mode for the specified window
//========================================================================

static void setStickyMouseButtons(_GLFWwindow* window, int enabled)
{
    if (window->stickyMouseButtons == enabled)
        return;

    if (!enabled)
    {
        int i;

        // Release all sticky mouse buttons
        for (i = 0;  i <= GLFW_MOUSE_BUTTON_LAST;  i++)
        {
            if (window->mouseButton[i] == GLFW_STICK)
                window->mouseButton[i] = GLFW_RELEASE;
        }
    }

    window->stickyMouseButtons = enabled;
}


//////////////////////////////////////////////////////////////////////////
//////                       GLFW internal API                      //////
//////////////////////////////////////////////////////////////////////////

//========================================================================
// Register keyboard activity
//========================================================================

void _glfwInputKey(_GLFWwindow* window, int key, int action)
{
    GLboolean repeated = GL_FALSE;

    if (key < 0 || key > GLFW_KEY_LAST)
        return;

    // Are we trying to release an already released key?
    if (action == GLFW_RELEASE && window->key[key] != GLFW_PRESS)
        return;

    // Register key action
    if (action == GLFW_RELEASE && window->stickyKeys)
        window->key[key] = GLFW_STICK;
    else
    {
        if (action == GLFW_PRESS && window->key[key] == GLFW_PRESS)
            repeated = GL_TRUE;

        window->key[key] = (char) action;
    }

    // Call user callback function
    if (window->callbacks.key && !repeated)
        window->callbacks.key((GLFWwindow*) window, key, action);
}


//========================================================================
// Register (keyboard) character activity
//========================================================================

void _glfwInputChar(_GLFWwindow* window, int character)
{
    // Valid Unicode (ISO 10646) character?
    if (!((character >= 32 && character <= 126) || character >= 160))
        return;

    if (window->callbacks.character)
        window->callbacks.character((GLFWwindow*) window, character);
}


//========================================================================
// Register scroll events
//========================================================================

void _glfwInputScroll(_GLFWwindow* window, double xoffset, double yoffset)
{
    window->scrollX += xoffset;
    window->scrollY += yoffset;

    if (window->callbacks.scroll)
        window->callbacks.scroll((GLFWwindow*) window, xoffset, yoffset);
}


//========================================================================
// Register mouse button clicks
//========================================================================

void _glfwInputMouseClick(_GLFWwindow* window, int button, int action)
{
    if (button < 0 || button > GLFW_MOUSE_BUTTON_LAST)
        return;

    // Register mouse button action
    if (action == GLFW_RELEASE && window->stickyMouseButtons)
        window->mouseButton[button] = GLFW_STICK;
    else
        window->mouseButton[button] = (char) action;

    if (window->callbacks.mouseButton)
        window->callbacks.mouseButton((GLFWwindow*) window, button, action);
}


//========================================================================
// Register cursor moves
//========================================================================

void _glfwInputCursorMotion(_GLFWwindow* window, int x, int y)
{
    if (window->cursorMode == GLFW_CURSOR_CAPTURED)
    {
        if (!x && !y)
            return;

        window->cursorPosX += x;
        window->cursorPosY += y;
    }
    else
    {
        if (window->cursorPosX == x && window->cursorPosY == y)
            return;

        window->cursorPosX = x;
        window->cursorPosY = y;
    }

    if (window->callbacks.cursorPos)
    {
        window->callbacks.cursorPos((GLFWwindow*) window,
                                    window->cursorPosX,
                                    window->cursorPosY);
    }
}


//========================================================================
// Register cursor enter/leave events
//========================================================================

void _glfwInputCursorEnter(_GLFWwindow* window, int entered)
{
    if (window->callbacks.cursorEnter)
        window->callbacks.cursorEnter((GLFWwindow*) window, entered);
}


//////////////////////////////////////////////////////////////////////////
//////                        GLFW public API                       //////
//////////////////////////////////////////////////////////////////////////

//========================================================================
// Returns the specified input mode of the specified window
//========================================================================

GLFWAPI int glfwGetInputMode(GLFWwindow* handle, int mode)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return 0;
    }

    switch (mode)
    {
        case GLFW_CURSOR_MODE:
            return window->cursorMode;
        case GLFW_STICKY_KEYS:
            return window->stickyKeys;
        case GLFW_STICKY_MOUSE_BUTTONS:
            return window->stickyMouseButtons;
        default:
            _glfwInputError(GLFW_INVALID_ENUM, NULL);
            return 0;
    }
}


//========================================================================
// Sets the specified input mode of the specified window
//========================================================================

GLFWAPI void glfwSetInputMode(GLFWwindow* handle, int mode, int value)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    switch (mode)
    {
        case GLFW_CURSOR_MODE:
            setCursorMode(window, value);
            break;
        case GLFW_STICKY_KEYS:
            setStickyKeys(window, value ? GL_TRUE : GL_FALSE);
            break;
        case GLFW_STICKY_MOUSE_BUTTONS:
            setStickyMouseButtons(window, value ? GL_TRUE : GL_FALSE);
            break;
        default:
            _glfwInputError(GLFW_INVALID_ENUM, NULL);
            break;
    }
}


//========================================================================
// Returns the state of the specified key for the specified window
//========================================================================

GLFWAPI int glfwGetKey(GLFWwindow* handle, int key)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return GLFW_RELEASE;
    }

    if (key < 0 || key > GLFW_KEY_LAST)
    {
        _glfwInputError(GLFW_INVALID_ENUM, "The specified key is invalid");
        return GLFW_RELEASE;
    }

    if (window->key[key] == GLFW_STICK)
    {
        // Sticky mode: release key now
        window->key[key] = GLFW_RELEASE;
        return GLFW_PRESS;
    }

    return (int) window->key[key];
}


//========================================================================
// Returns the state of the specified mouse button for the specified window
//========================================================================

GLFWAPI int glfwGetMouseButton(GLFWwindow* handle, int button)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return GLFW_RELEASE;
    }

    if (button < 0 || button > GLFW_MOUSE_BUTTON_LAST)
    {
        _glfwInputError(GLFW_INVALID_ENUM,
                        "The specified mouse button is invalid");
        return GLFW_RELEASE;
    }

    if (window->mouseButton[button] == GLFW_STICK)
    {
        // Sticky mode: release mouse button now
        window->mouseButton[button] = GLFW_RELEASE;
        return GLFW_PRESS;
    }

    return (int) window->mouseButton[button];
}


//========================================================================
// Returns the last reported cursor position for the specified window
//========================================================================

GLFWAPI void glfwGetCursorPos(GLFWwindow* handle, int* xpos, int* ypos)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    if (xpos != NULL)
        *xpos = window->cursorPosX;

    if (ypos != NULL)
        *ypos = window->cursorPosY;
}


//========================================================================
// Sets the cursor position relative to the position of the client area of
// the specified window
//========================================================================

GLFWAPI void glfwSetCursorPos(GLFWwindow* handle, int xpos, int ypos)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    if (_glfw.focusedWindow != window)
        return;

    // Don't do anything if the cursor position did not change
    if (xpos == window->cursorPosX && ypos == window->cursorPosY)
        return;

    // Set GLFW cursor position
    window->cursorPosX = xpos;
    window->cursorPosY = ypos;

    // Do not move physical cursor in locked cursor mode
    if (window->cursorMode == GLFW_CURSOR_CAPTURED)
        return;

    // Update physical cursor position
    _glfwPlatformSetCursorPos(window, xpos, ypos);
}


//========================================================================
// Returns the scroll offset for the specified window
//========================================================================

GLFWAPI void glfwGetScrollOffset(GLFWwindow* handle, double* xoffset, double* yoffset)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    if (xoffset)
      *xoffset = window->scrollX;

    if (yoffset)
      *yoffset = window->scrollY;
}


//========================================================================
// Set callback function for keyboard input
//========================================================================

GLFWAPI void glfwSetKeyCallback(GLFWwindow* handle, GLFWkeyfun cbfun)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    window->callbacks.key = cbfun;
}


//========================================================================
// Set callback function for character input
//========================================================================

GLFWAPI void glfwSetCharCallback(GLFWwindow* handle, GLFWcharfun cbfun)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    window->callbacks.character = cbfun;
}


//========================================================================
// Set callback function for mouse clicks
//========================================================================

GLFWAPI void glfwSetMouseButtonCallback(GLFWwindow* handle, GLFWmousebuttonfun cbfun)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    window->callbacks.mouseButton = cbfun;
}


//========================================================================
// Set callback function for mouse moves
//========================================================================

GLFWAPI void glfwSetCursorPosCallback(GLFWwindow* handle, GLFWcursorposfun cbfun)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    window->callbacks.cursorPos = cbfun;
}


//========================================================================
// Set callback function for cursor enter/leave events
//========================================================================

GLFWAPI void glfwSetCursorEnterCallback(GLFWwindow* handle, GLFWcursorenterfun cbfun)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    window->callbacks.cursorEnter = cbfun;
}


//========================================================================
// Set callback function for scroll events
//========================================================================

GLFWAPI void glfwSetScrollCallback(GLFWwindow* handle, GLFWscrollfun cbfun)
{
    _GLFWwindow* window = (_GLFWwindow*) handle;

    if (!_glfwInitialized)
    {
        _glfwInputError(GLFW_NOT_INITIALIZED, NULL);
        return;
    }

    window->callbacks.scroll = cbfun;
}