/*  Audacious - Cross-platform multimedia player
 *  Copyright (C) 2005-2007  Audacious development team
 *
 *  Based on BMP:
 *  Copyright (C) 2003-2004  BMP development team.
 *
 *  Based on XMMS:
 *  Copyright (C) 1998-2003  XMMS development team.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; under version 3 of the License.
 *
 *  This program 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 for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program.  If not, see <http://www.gnu.org/licenses>.
 *
 *  The Audacious team does not consider modular code linking to
 *  Audacious or using our public API to be a derived work.
 */

#include "dock.h"

#include <gdk/gdk.h>
#include <stdlib.h>
#include "main.h"

#include "platform/smartinclude.h"

struct _DockedWindow {
    GtkWindow *w;
    gint offset_x, offset_y;
};

typedef struct _DockedWindow DockedWindow;


static gint
docked_list_compare(DockedWindow * a, DockedWindow * b)
{
    if (a->w == b->w)
        return 0;
    return 1;
}

static void
snap_edge(gint * x, gint * y, gint w, gint h, gint bx, gint by,
          gint bw, gint bh)
{
    gint sd = cfg.snap_distance;

    if ((*x + w > bx - sd) && (*x + w < bx + sd) &&
        (*y > by - h - sd) && (*y < by + bh + sd)) {
        *x = bx - w;
        if ((*y > by - sd) && (*y < by + sd))
            *y = by;
        if ((*y + h > by + bh - sd) && (*y + h < by + bh + sd))
            *y = by + bh - h;
    }
    if ((*x > bx + bw - sd) && (*x < bx + bw + sd) &&
        (*y > by - h - sd) && (*y < by + bh + sd)) {
        *x = bx + bw;
        if ((*y > by - sd) && (*y < by + sd))
            *y = by;
        if ((*y + h > by + bh - sd) && (*y + h < by + bh + sd))
            *y = by + bh - h;
    }
}

static void
snap(gint * x, gint * y, gint w, gint h, gint bx, gint by, gint bw, gint bh)
{
    snap_edge(x, y, w, h, bx, by, bw, bh);
    snap_edge(y, x, h, w, by, bx, bh, bw);
}

static void
calc_snap_offset(GList * dlist, GList * wlist, gint x, gint y,
                 gint * off_x, gint * off_y)
{
    gint nx, ny, nw, nh, sx, sy, sw, sh;
    GtkWindow *w;
    GList *dnode, *wnode;
    DockedWindow temp, *dw;


    *off_x = 0;
    *off_y = 0;

    if (!cfg.snap_windows)
        return;

    /*
     * FIXME: Why not break out of the loop when we find someting
     * to snap to?
     */
    for (dnode = dlist; dnode; dnode = g_list_next(dnode)) {
        dw = dnode->data;
        gtk_window_get_size(dw->w, &nw, &nh);

        nx = dw->offset_x + *off_x + x;
        ny = dw->offset_y + *off_y + y;

        /* Snap to screen edges */
        if (abs(nx) < cfg.snap_distance)
            *off_x -= nx;
        if (abs(ny) < cfg.snap_distance)
            *off_y -= ny;
        if (abs(nx + nw - gdk_screen_width()) < cfg.snap_distance)
            *off_x -= nx + nw - gdk_screen_width();
        if (abs(ny + nh - gdk_screen_height()) < cfg.snap_distance)
            *off_y -= ny + nh - gdk_screen_height();

        /* Snap to other windows */
        for (wnode = wlist; wnode; wnode = g_list_next(wnode)) {
            temp.w = wnode->data;
            if (g_list_find_custom
                (dlist, &temp, (GCompareFunc) docked_list_compare))
                /* These windows are already docked */
                continue;

            w = GTK_WINDOW(wnode->data);
            gtk_window_get_position(w, &sx, &sy);
            gtk_window_get_size(w, &sw, &sh);

            nx = dw->offset_x + *off_x + x;
            ny = dw->offset_y + *off_y + y;

            snap(&nx, &ny, nw, nh, sx, sy, sw, sh);

            *off_x += nx - (dw->offset_x + *off_x + x);
            *off_y += ny - (dw->offset_y + *off_y + y);
        }
    }
}


static gboolean
is_docked(gint a_x, gint a_y, gint a_w, gint a_h,
          gint b_x, gint b_y, gint b_w, gint b_h)
{
    if (((a_x == b_x + b_w) || (a_x + a_w == b_x)) &&
        (b_y + b_h >= a_y) && (b_y <= a_y + a_h))
        return TRUE;

    if (((a_y == b_y + b_h) || (a_y + a_h == b_y)) &&
        (b_x >= a_x - b_w) && (b_x <= a_x + a_w))
        return TRUE;

    return FALSE;
}

/*
 * Builds a list of all windows that are docked to the window "w".
 * Recursively adds all windows that are docked to the windows that are
 * docked to "w" and so on...
 * FIXME: init_off_?  ?
 */

static GList *
get_docked_list(GList * dlist, GList * wlist, GtkWindow * w,
                gint init_off_x, gint init_off_y)
{
    GList *node;
    DockedWindow *dwin, temp;
    gint w_x, w_y, w_width, w_height;
    gint t_x, t_y, t_width, t_height;


    gtk_window_get_position(w, &w_x, &w_y);
    gtk_window_get_size(w, &w_width, &w_height);
    if (!dlist) {
        dwin = g_new0(DockedWindow, 1);
        dwin->w = w;
        dlist = g_list_append(dlist, dwin);
    }

    for (node = wlist; node; node = g_list_next(node)) {
        temp.w = node->data;
        if (g_list_find_custom
            (dlist, &temp, (GCompareFunc) docked_list_compare))
            continue;

        gtk_window_get_position(GTK_WINDOW(node->data), &t_x, &t_y);
        gtk_window_get_size(GTK_WINDOW(node->data), &t_width, &t_height);
        if (is_docked
            (w_x, w_y, w_width, w_height, t_x, t_y, t_width, t_height)) {
            dwin = g_new0(DockedWindow, 1);
            dwin->w = node->data;

            dwin->offset_x = t_x - w_x + init_off_x;
            dwin->offset_y = t_y - w_y + init_off_y;

            dlist = g_list_append(dlist, dwin);

            dlist =
                get_docked_list(dlist, wlist, dwin->w, dwin->offset_x,
                                dwin->offset_y);
        }
    }
    return dlist;
}

static void
free_docked_list(GList * dlist)
{
    GList *node;

    for (node = dlist; node; node = g_list_next(node))
        g_free(node->data);
    g_list_free(dlist);
}

static void
docked_list_move(GList * list, gint x, gint y)
{
    GList *node;
    DockedWindow *dw;

    for (node = list; node; node = g_list_next(node)) {
        dw = node->data;
        gtk_window_move(dw->w, x + dw->offset_x, y + dw->offset_y);
    }
}

static GList *
shade_move_list(GList * list, GtkWindow * widget, gint offset)
{
    gint x, y, w, h;
    GList *node;
    DockedWindow *dw;

    gtk_window_get_position(widget, &x, &y);
    gtk_window_get_size(widget, &w, &h);


    for (node = list; node;) {
        gint dx, dy, dwidth, dheight;

        dw = node->data;
        gtk_window_get_position(dw->w, &dx, &dy);
        gtk_window_get_size(dw->w, &dwidth, &dheight);
        if (is_docked(x, y, w, h, dx, dy, dwidth, dheight) &&
            ((dx + dwidth) > x && dx < (x + w))) {
            list = g_list_remove_link(list, node);
            g_list_free_1(node);

            node = list = shade_move_list(list, dw->w, offset);
        }
        else
            node = g_list_next(node);
    }
    gtk_window_move(widget, x, y + offset);
    return list;
}

/*
 * Builds a list of the windows in the list of DockedWindows "winlist"
 * that are docked to the top or bottom of the window, and recursively
 * adds all windows that are docked to the top or bottom of that window,
 * and so on...
 * Note: The data in "winlist" is not copied.
 */
static GList *
find_shade_list(GtkWindow * widget, GList * winlist, GList * shade_list)
{
    gint x, y, w, h;
    gint dx, dy, dwidth, dheight;
    GList *node;

    gtk_window_get_position(widget, &x, &y);
    gtk_window_get_size(widget, &w, &h);
    for (node = winlist; node; node = g_list_next(node)) {
        DockedWindow *dw = node->data;
        if (g_list_find_custom
            (shade_list, dw, (GCompareFunc) docked_list_compare))
            continue;
        gtk_window_get_position(dw->w, &dx, &dy);
        gtk_window_get_size(dw->w, &dwidth, &dheight);

        /* FIXME. Is the is_docked() necessary? */
        if (is_docked(x, y, w, h, dx, dy, dwidth, dheight) &&
            ((dx + dwidth) > x && dx < (x + w))) {
            shade_list = g_list_append(shade_list, dw);
            shade_list = find_shade_list(dw->w, winlist, shade_list);
        }
    }
    return shade_list;
}

void
dock_window_resize(GtkWindow * widget, gint new_w, gint new_h, gint w, gint h)
{
    gdk_window_set_hints(GTK_WIDGET(widget)->window, 0, 0, MIN(w, new_w),
                         MIN(h, new_h), MAX(w, new_w), MAX(h, new_h),
                         GDK_HINT_MIN_SIZE | GDK_HINT_MAX_SIZE);
    gdk_window_resize(GTK_WIDGET(widget)->window, new_w, new_h);
    gdk_window_set_hints(GTK_WIDGET(widget)->window, 0, 0, new_w, new_h,
                         new_w, new_h, GDK_HINT_MIN_SIZE | GDK_HINT_MAX_SIZE);
}

void
dock_shade(GList * window_list, GtkWindow * widget, gint new_h)
{
    gint x, y, w, h, off_y, orig_off_y;
    GList *node, *docked_list, *slist;
    DockedWindow *dw;

    gtk_window_get_position(widget, &x, &y);
    gtk_window_get_size(widget, &w, &h);

    if (cfg.show_wm_decorations) {
        dock_window_resize(widget, w, new_h, w, h);
        return;
    }

    docked_list = get_docked_list(NULL, window_list, widget, 0, 0);
    slist = find_shade_list(widget, docked_list, NULL);

    off_y = new_h - h;
    do {
        orig_off_y = off_y;
        for (node = slist; node; node = g_list_next(node)) {
            gint dx, dy, dwidth, dheight;

            dw = node->data;
            if (dw->w == widget)
                continue;
            gtk_window_get_position(dw->w, &dx, &dy);
            gtk_window_get_size(dw->w, &dwidth, &dheight);
            if ((dy >= y) && ((dy + off_y + dheight) > gdk_screen_height()))
                off_y -= (dy + off_y + dheight) - gdk_screen_height();
            else if ((dy >= y) && ((dy + dheight) == gdk_screen_height()))
                off_y = 0;

            if (((dy >= y) && ((dy + off_y) < 0)))
                off_y -= dy + off_y;
            if ((dy < y) && ((dy + (off_y - (new_h - h))) < 0))
                off_y -= dy + (off_y - (new_h - h));
        }
    } while (orig_off_y != off_y);
    if (slist) {
        GList *mlist = g_list_copy(slist);

        /* Remove this widget from the list */
        for (node = mlist; node; node = g_list_next(node)) {
            dw = node->data;
            if (dw->w == widget) {
                mlist = g_list_remove_link(mlist, node);
                g_list_free_1(node);
                break;
            }
        }
        for (node = mlist; node;) {
            GList *temp;
            gint dx, dy, dwidth, dheight;

            dw = node->data;

            gtk_window_get_position(dw->w, &dx, &dy);
            gtk_window_get_size(dw->w, &dwidth, &dheight);
            /*
             * Find windows that are directly docked to this window,
             * move it, and any windows docked to that window again
             */
            if (is_docked(x, y, w, h, dx, dy, dwidth, dheight) &&
                ((dx + dwidth) > x && dx < (x + w))) {
                mlist = g_list_remove_link(mlist, node);
                g_list_free_1(node);
                if (dy > y)
                    temp = shade_move_list(mlist, dw->w, off_y);
                else if (off_y - (new_h - h) != 0)
                    temp = shade_move_list(mlist, dw->w, off_y - (new_h - h));
                else
                    temp = mlist;
                node = mlist = temp;
            }
            else
                node = g_list_next(node);
        }
        g_list_free(mlist);
    }
    g_list_free(slist);
    free_docked_list(docked_list);
    gtk_window_move(widget, x, y + off_y - (new_h - h));
    dock_window_resize(widget, w, new_h, w, h);
}

static GList *
resize_move_list(GList * list, GtkWindow * widget,
                 gint offset_x, gint offset_y)
{
    gint x, y, w, h;
    GList *node;
    DockedWindow *dw;

    gtk_window_get_position(widget, &x, &y);
    gtk_window_get_size(widget, &w, &h);


    for (node = list; node;) {
        gint dx, dy, dwidth, dheight;
        dw = node->data;
        gtk_window_get_position(dw->w, &dx, &dy);
        gtk_window_get_size(dw->w, &dwidth, &dheight);
        if (is_docked(x, y, w, h, dx, dy, dwidth, dheight)) {

            list = g_list_remove_link(list, node);
            g_list_free_1(node);
            node = list = resize_move_list(list, dw->w, offset_x, offset_y);
        }
        else
            node = g_list_next(node);
    }
    gtk_window_move(widget, x + offset_x, y + offset_y);
    return list;
}

static GList *
resize_calc_offset(GList * list, GtkWindow * widget,
                   gint offset_x, gint offset_y,
                   gint * goffset_x, gint * goffset_y)
{
    gint x, y, w, h;
    GList *node;
    DockedWindow *dw;

    gtk_window_get_position(widget, &x, &y);
    gtk_window_get_size(widget, &w, &h);


    for (node = list; node;) {
        gint dx, dy, dwidth, dheight;
        dw = node->data;
        gtk_window_get_position(dw->w, &dx, &dy);
        gtk_window_get_size(dw->w, &dwidth, &dheight);
        if (is_docked(x, y, w, h, dx, dy, dwidth, dheight)) {
            if (dx + offset_x + dwidth > gdk_screen_width()) {
                offset_x -= dx + offset_x + dwidth - gdk_screen_width();
                (*goffset_x) -= dx + offset_x + dwidth - gdk_screen_width();
            }
            if (dy + offset_y + dheight > gdk_screen_height()) {
                offset_y -= dy + offset_y + dheight - gdk_screen_height();
                (*goffset_y) -= dy + offset_y + dheight - gdk_screen_height();
            }
            list = g_list_remove_link(list, node);
            g_list_free_1(node);
            node = list =
                resize_calc_offset(list, dw->w, offset_x, offset_y,
                                   goffset_x, goffset_y);
        }
        else
            node = g_list_next(node);
    }
    return list;
}

void
dock_move_press(GList * window_list, GtkWindow * w,
                GdkEventButton * event, gboolean move_list)
{
    gint mx, my;
    DockedWindow *dwin;

    if (cfg.show_wm_decorations)
        return;

    gtk_window_present(w);
    mx = event->x;
    my = event->y;
    gtk_object_set_data(GTK_OBJECT(w), "move_offset_x", GINT_TO_POINTER(mx));
    gtk_object_set_data(GTK_OBJECT(w), "move_offset_y", GINT_TO_POINTER(my));
    if (move_list)
        gtk_object_set_data(GTK_OBJECT(w), "docked_list",
                            get_docked_list(NULL, window_list, w, 0, 0));
    else {
        dwin = g_new0(DockedWindow, 1);
        dwin->w = w;
        gtk_object_set_data(GTK_OBJECT(w), "docked_list",
                            g_list_append(NULL, dwin));
    }
    gtk_object_set_data(GTK_OBJECT(w), "window_list", window_list);
    gtk_object_set_data(GTK_OBJECT(w), "is_moving", GINT_TO_POINTER(1));
}

void
dock_move_motion(GtkWindow * w, GdkEventMotion * event)
{
    gint offset_x, offset_y, win_x, win_y, x, y;
    GList *dlist;
    GList *window_list;

    if (!gtk_object_get_data(GTK_OBJECT(w), "is_moving"))
        return;

    offset_x =
        GPOINTER_TO_INT(gtk_object_get_data(GTK_OBJECT(w), "move_offset_x"));
    offset_y =
        GPOINTER_TO_INT(gtk_object_get_data(GTK_OBJECT(w), "move_offset_y"));
    dlist = gtk_object_get_data(GTK_OBJECT(w), "docked_list");
    window_list = gtk_object_get_data(GTK_OBJECT(w), "window_list");

    gtk_window_get_position(w, &win_x, &win_y);

    x = event->x_root - offset_x;
    y = event->y_root - offset_y;

    calc_snap_offset(dlist, window_list, x, y, &offset_x, &offset_y);
    x += offset_x;
    y += offset_y;

    docked_list_move(dlist, x, y);
}

void
dock_move_release(GtkWindow * w)
{
    GList *dlist;
    gtk_object_remove_data(GTK_OBJECT(w), "is_moving");
    gtk_object_remove_data(GTK_OBJECT(w), "move_offset_x");
    gtk_object_remove_data(GTK_OBJECT(w), "move_offset_y");
    if ((dlist = gtk_object_get_data(GTK_OBJECT(w), "docked_list")) != NULL)
        free_docked_list(dlist);
    gtk_object_remove_data(GTK_OBJECT(w), "docked_list");
    gtk_object_remove_data(GTK_OBJECT(w), "window_list");
}

gboolean
dock_is_moving(GtkWindow * w)
{
    if (gtk_object_get_data(GTK_OBJECT(w), "is_moving"))
        return TRUE;
    return FALSE;
}

GList *
dock_add_window(GList * list, GtkWindow * window)
{
    return g_list_append(list, window);
}

GList *
dock_remove_window(GList * list, GtkWindow * window)
{
    return g_list_remove(list, window);
}

GList *
dock_window_set_decorated(GList * list, GtkWindow * window,
                          gboolean decorated)
{
    if (gtk_window_get_decorated(window) == decorated)
        return list;

    if (decorated)
        list = dock_remove_window(list, window);
    else
        list = dock_add_window(list, window);

    gtk_window_set_decorated(window, decorated);

    return list;
}

GList *
get_dock_window_list() {
    return dock_window_list;
}
