/*
 * Copyright (c) 2013, 2015, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

#include "glass_screen.h"
#include "glass_general.h"

#include <X11/Xatom.h>
#include <gdk/gdk.h>
#include <gdk/gdkx.h>

static guint get_current_desktop(GdkScreen *screen) {
    Display* display = gdk_x11_display_get_xdisplay(gdk_display_get_default());
    Atom currentDesktopAtom = XInternAtom(display, "_NET_CURRENT_DESKTOP", True);
    guint ret = 0;

    Atom type;
    int format;
    gulong num, left;
    unsigned long *data = NULL;

    if (currentDesktopAtom == None) {
        return 0;
    }

    int result = XGetWindowProperty(display,
                                    GDK_WINDOW_XID(gdk_screen_get_root_window(screen)),
                                    currentDesktopAtom, 0, G_MAXLONG, False, XA_CARDINAL,
                                    &type, &format, &num, &left, (unsigned char **)&data);

    if ((result == Success) && (data != NULL)) {
        if (type == XA_CARDINAL && format == 32) {
            ret = data[0];
        }

        XFree(data);
    }

    return ret;

}

static GdkRectangle get_screen_workarea(GdkScreen *screen) {
    Display* display = gdk_x11_display_get_xdisplay(gdk_display_get_default());
    GdkRectangle ret = { 0, 0, gdk_screen_get_width(screen), gdk_screen_get_height(screen)};

    Atom workareaAtom = XInternAtom(display, "_NET_WORKAREA", True);

    Atom type;
    int format;
    gulong num, left;
    unsigned long *data = NULL;

    if (workareaAtom == None) {
        return ret;
    }

    int result = XGetWindowProperty(display,
                                    GDK_WINDOW_XID(gdk_screen_get_root_window(screen)),
                                    workareaAtom, 0, G_MAXLONG, False, AnyPropertyType,
                                    &type, &format, &num, &left, (unsigned char **)&data);

    if ((result == Success) && (data != NULL)) {
        if (type != None && format == 32) {
            guint current_desktop = get_current_desktop(screen);
            if (current_desktop < num / 4) {
                ret.x = data[current_desktop * 4];
                ret.y = data[current_desktop * 4 + 1];
                ret.width = data[current_desktop * 4 + 2];
                ret.height = data[current_desktop * 4 + 3];
            }
        }

        XFree(data);
    }

    return ret;

}

static jobject createJavaScreen(JNIEnv* env, GdkScreen* screen, gint monitor_idx)
{
    GdkRectangle workArea = get_screen_workarea(screen);
    LOG4("Work Area: x:%d, y:%d, w:%d, h:%d\n", workArea.x, workArea.y, workArea.width, workArea.height);

    GdkRectangle monitor_geometry;
    gdk_screen_get_monitor_geometry(screen, monitor_idx, &monitor_geometry);
    LOG1("convert monitor[%d] -> glass Screen\n", monitor_idx)
    LOG4("[x: %d y: %d w: %d h: %d]\n",
         monitor_geometry.x, monitor_geometry.y,
         monitor_geometry.width, monitor_geometry.height)

    GdkVisual* visual = gdk_screen_get_system_visual(screen);

    GdkRectangle working_monitor_geometry;
    gdk_rectangle_intersect(&workArea, &monitor_geometry, &working_monitor_geometry);

    jobject jScreen = env->NewObject(jScreenCls, jScreenInit,
                                     (jlong)monitor_idx,

                                     (visual ? gdk_visual_get_depth(visual) : 0),

                                     monitor_geometry.x,
                                     monitor_geometry.y,
                                     monitor_geometry.width,
                                     monitor_geometry.height,

                                     monitor_geometry.x,
                                     monitor_geometry.y,
                                     monitor_geometry.width,
                                     monitor_geometry.height,

                                     working_monitor_geometry.x,
                                     working_monitor_geometry.y,
                                     working_monitor_geometry.width,
                                     working_monitor_geometry.height,

                                     (jint)gdk_screen_get_resolution(screen),
                                     (jint)gdk_screen_get_resolution(screen),
                                     1.0f, 1.0f, 1.0f, 1.0f);
    JNI_EXCEPTION_TO_CPP(env);
    return jScreen;
}

jobject createJavaScreen(JNIEnv* env, gint monitor_idx) {
    GdkScreen *default_gdk_screen = gdk_screen_get_default();
    try {
        return createJavaScreen(env, default_gdk_screen, monitor_idx);
    } catch (jni_exception&) {
        return NULL;
    }
}

jobjectArray rebuild_screens(JNIEnv* env) {
    GdkScreen *default_gdk_screen = gdk_screen_get_default();
    gint n_monitors = gdk_screen_get_n_monitors(default_gdk_screen);

    jobjectArray jscreens = env->NewObjectArray(n_monitors, jScreenCls, NULL);
    JNI_EXCEPTION_TO_CPP(env)
    LOG1("Available monitors: %d\n", n_monitors)

    int i;
    for (i=0; i < n_monitors; i++) {
        env->SetObjectArrayElement(jscreens, i, createJavaScreen(env, default_gdk_screen, i));
        JNI_EXCEPTION_TO_CPP(env)
    }

    return jscreens;
}


glong getScreenPtrForLocation(gint x, gint y) {
    //Note: we are relying on the fact that javafx_screen_id == gdk_monitor_id
    return gdk_screen_get_monitor_at_point(gdk_screen_get_default(), x, y);
}

void screen_settings_changed(GdkScreen* screen, gpointer user_data) {
    (void)screen;
    (void)user_data;

    mainEnv->CallStaticVoidMethod(jScreenCls, jScreenNotifySettingsChanged);
    LOG_EXCEPTION(mainEnv);
}