//========================================================================
// GLFW 3.1 Wayland - www.glfw.org
//------------------------------------------------------------------------
// Copyright (c) 2014 Jonas Ådahl <jadahl@gmail.com>
//
// 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"

#include <linux/input.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wayland-client.h>
#include <wayland-client-protocol.h>
#include <wayland-cursor.h>


static void handlePing(void* data,
                       struct wl_shell_surface* shellSurface,
                       uint32_t serial)
{
    wl_shell_surface_pong(shellSurface, serial);
}

static void handleConfigure(void* data,
                            struct wl_shell_surface* shellSurface,
                            uint32_t edges,
                            int32_t width,
                            int32_t height)
{
}

static void handlePopupDone(void *data, struct wl_shell_surface *shell_surface)
{
}

static const struct wl_shell_surface_listener shellSurfaceListener = {
    handlePing,
    handleConfigure,
    handlePopupDone
};

static void pointerHandleEnter(void* data,
                               struct wl_pointer* pointer,
                               uint32_t serial,
                               struct wl_surface* surface,
                               wl_fixed_t sx,
                               wl_fixed_t sy)
{
    _GLFWwindow* window = wl_surface_get_user_data(surface);

    _glfw.wl.pointerFocus = window;
    _glfwInputCursorEnter(window, GL_TRUE);
}

static void pointerHandleLeave(void* data,
                               struct wl_pointer* pointer,
                               uint32_t serial,
                               struct wl_surface* surface)
{
    _GLFWwindow* window = wl_surface_get_user_data(surface);

    _glfw.wl.pointerFocus = NULL;
    _glfwInputCursorEnter(window, GL_FALSE);
}

static void pointerHandleMotion(void* data,
                                struct wl_pointer* pointer,
                                uint32_t time,
                                wl_fixed_t sx,
                                wl_fixed_t sy)
{
    _GLFWwindow* window = _glfw.wl.pointerFocus;

    if (window->cursorMode == GLFW_CURSOR_DISABLED)
    {
        /* TODO */
        _glfwInputError(GLFW_PLATFORM_ERROR,
                        "Wayland: GLFW_CURSOR_DISABLED not supported");
        return;
    }

    _glfwInputCursorMotion(window,
                           wl_fixed_to_double(sx),
                           wl_fixed_to_double(sy));
}

static void pointerHandleButton(void* data,
                                struct wl_pointer* wl_pointer,
                                uint32_t serial,
                                uint32_t time,
                                uint32_t button,
                                uint32_t state)
{
    _GLFWwindow* window = _glfw.wl.pointerFocus;
    int glfwButton;

    /* Makes left, right and middle 0, 1 and 2. Overall order follows evdev
     * codes. */
    glfwButton = button - BTN_LEFT;

    /* TODO: modifiers */
    _glfwInputMouseClick(window,
                         glfwButton,
                         state == WL_POINTER_BUTTON_STATE_PRESSED
                                ? GLFW_PRESS
                                : GLFW_RELEASE,
                         0);
}

static void pointerHandleAxis(void* data,
                              struct wl_pointer* wl_pointer,
                              uint32_t time,
                              uint32_t axis,
                              wl_fixed_t value)
{
    _GLFWwindow* window = _glfw.wl.pointerFocus;
    double scroll_factor;
    double x, y;

    /* Wayland scroll events are in pointer motion coordinate space (think
     * two finger scroll). The factor 10 is commonly used to convert to
     * "scroll step means 1.0. */
    scroll_factor = 1.0/10.0;

    switch (axis)
    {
        case WL_POINTER_AXIS_HORIZONTAL_SCROLL:
            x = wl_fixed_to_double(value) * scroll_factor;
            y = 0.0;
            break;
        case WL_POINTER_AXIS_VERTICAL_SCROLL:
            x = 0.0;
            y = wl_fixed_to_double(value) * scroll_factor;
            break;
        default:
            break;
    }

    _glfwInputScroll(window, x, y);
}

static const struct wl_pointer_listener pointerListener = {
    pointerHandleEnter,
    pointerHandleLeave,
    pointerHandleMotion,
    pointerHandleButton,
    pointerHandleAxis,
};

static void keyboardHandleKeymap(void* data,
                                 struct wl_keyboard* keyboard,
                                 uint32_t format,
                                 int fd,
                                 uint32_t size)
{
    /* TODO */
}

static void keyboardHandleEnter(void* data,
                                struct wl_keyboard* keyboard,
                                uint32_t serial,
                                struct wl_surface* surface,
                                struct wl_array* keys)
{
    _glfwInputWindowFocus(wl_surface_get_user_data(surface), GL_TRUE);
}

static void keyboardHandleLeave(void* data,
                                struct wl_keyboard* keyboard,
                                uint32_t serial,
                                struct wl_surface* surface)
{
    _glfwInputWindowFocus(wl_surface_get_user_data(surface), GL_FALSE);
}

static void keyboardHandleKey(void* data,
                              struct wl_keyboard* keyboard,
                              uint32_t serial,
                              uint32_t time,
                              uint32_t key,
                              uint32_t state)
{
    /* TODO */
}

static void keyboardHandleModifiers(void* data,
                                    struct wl_keyboard* keyboard,
                                    uint32_t serial,
                                    uint32_t modsDepressed,
                                    uint32_t modsLatched,
                                    uint32_t modsLocked,
                                    uint32_t group)
{
    /* TODO */
}

static const struct wl_keyboard_listener keyboardListener = {
    keyboardHandleKeymap,
    keyboardHandleEnter,
    keyboardHandleLeave,
    keyboardHandleKey,
    keyboardHandleModifiers,
};

static void seatHandleCapabilities(void* data,
                                   struct wl_seat* seat,
                                   enum wl_seat_capability caps)
{
    if ((caps & WL_SEAT_CAPABILITY_POINTER) && !_glfw.wl.pointer)
    {
        _glfw.wl.pointer = wl_seat_get_pointer(seat);
        wl_pointer_add_listener(_glfw.wl.pointer, &pointerListener, NULL);
    }
    else if (!(caps & WL_SEAT_CAPABILITY_POINTER) && _glfw.wl.pointer)
    {
        wl_pointer_destroy(_glfw.wl.pointer);
        _glfw.wl.pointer = NULL;
    }

    if ((caps & WL_SEAT_CAPABILITY_KEYBOARD) && !_glfw.wl.keyboard)
    {
        _glfw.wl.keyboard = wl_seat_get_keyboard(seat);
        wl_keyboard_add_listener(_glfw.wl.keyboard, &keyboardListener, NULL);
    }
    else if (!(caps & WL_SEAT_CAPABILITY_KEYBOARD) && _glfw.wl.keyboard)
    {
        wl_keyboard_destroy(_glfw.wl.keyboard);
        _glfw.wl.keyboard = NULL;
    }
}

static const struct wl_seat_listener seatListener = {
    seatHandleCapabilities
};

static void registryHandleGlobal(void* data,
                                 struct wl_registry* registry,
                                 uint32_t name,
                                 const char* interface,
                                 uint32_t version)
{
    if (strcmp(interface, "wl_compositor") == 0)
    {
        _glfw.wl.compositor =
            wl_registry_bind(registry, name, &wl_compositor_interface, 1);
    }
    else if (strcmp(interface, "wl_shell") == 0)
    {
        _glfw.wl.shell =
            wl_registry_bind(registry, name, &wl_shell_interface, 1);
    }
    else if (strcmp(interface, "wl_output") == 0)
    {
        _glfwAddOutput(name, version);
    }
    else if (strcmp(interface, "wl_seat") == 0)
    {
        if (!_glfw.wl.seat)
        {
            _glfw.wl.seat =
                wl_registry_bind(registry, name, &wl_seat_interface, 1);
            wl_seat_add_listener(_glfw.wl.seat, &seatListener, NULL);
        }
    }
}

static void registryHandleGlobalRemove(void *data,
                                       struct wl_registry *registry,
                                       uint32_t name)
{
}


static const struct wl_registry_listener registryListener = {
    registryHandleGlobal,
    registryHandleGlobalRemove
};


//////////////////////////////////////////////////////////////////////////
//////                       GLFW platform API                      //////
//////////////////////////////////////////////////////////////////////////

int _glfwPlatformInit(void)
{
    _glfw.wl.display = wl_display_connect(NULL);
    if (!_glfw.wl.display)
    {
        _glfwInputError(GLFW_PLATFORM_ERROR,
                        "Wayland: Failed to connect to display");
        return GL_FALSE;
    }

    _glfw.wl.registry = wl_display_get_registry(_glfw.wl.display);
    wl_registry_add_listener(_glfw.wl.registry, &registryListener, NULL);

    _glfw.wl.monitors = calloc(4, sizeof(_GLFWmonitor*));
    _glfw.wl.monitorsSize = 4;

    // Sync so we got all registry objects
    wl_display_roundtrip(_glfw.wl.display);

    // Sync so we got all initial output events
    wl_display_roundtrip(_glfw.wl.display);

    if (!_glfwInitContextAPI())
        return GL_FALSE;

    _glfwInitTimer();
    _glfwInitJoysticks();

    return GL_TRUE;
}

void _glfwPlatformTerminate(void)
{
    _glfwTerminateContextAPI();

    if (_glfw.wl.registry)
        wl_registry_destroy(_glfw.wl.registry);
    if (_glfw.wl.display)
        wl_display_flush(_glfw.wl.display);
    if (_glfw.wl.display)
        wl_display_disconnect(_glfw.wl.display);
}

const char* _glfwPlatformGetVersionString(void)
{
    const char* version = _GLFW_VERSION_NUMBER " Wayland EGL "
#if defined(_POSIX_TIMERS) && defined(_POSIX_MONOTONIC_CLOCK)
        " clock_gettime"
#endif
#if defined(_GLFW_BUILD_DLL)
        " shared"
#endif
        ;

    return version;
}