netsurf/render/html_interaction.c
Michael Drake 6c59c80ed5 s/int/size_t/
svn path=/trunk/netsurf/; revision=10562
2010-06-04 09:39:30 +00:00

883 lines
22 KiB
C

/*
* Copyright 2006 James Bursa <bursa@users.sourceforge.net>
* Copyright 2006 Richard Wilson <info@tinct.net>
* Copyright 2008 Michael Drake <tlsa@netsurf-browser.org>
* Copyright 2009 Paul Blokus <paul_pl@users.sourceforge.net>
*
* This file is part of NetSurf, http://www.netsurf-browser.org/
*
* NetSurf 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; version 2 of the License.
*
* NetSurf 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/>.
*/
/** \file
* User interaction with a CONTENT_HTML (implementation).
*/
#include <assert.h>
#include <stdbool.h>
#include "content/content.h"
#include "desktop/browser.h"
#include "desktop/frames.h"
#include "desktop/mouse.h"
#include "desktop/options.h"
#include "desktop/scroll.h"
#include "desktop/selection.h"
#include "desktop/textinput.h"
#include "render/box.h"
#include "render/font.h"
#include "render/form.h"
#include "render/html.h"
#include "render/imagemap.h"
#include "utils/messages.h"
#include "utils/utils.h"
static gui_pointer_shape get_pointer_shape(struct browser_window *bw,
struct box *box, bool imagemap);
static void html_box_drag_start(struct box *box, int x, int y);
/**
* Handle mouse tracking (including drags) in an HTML content window.
*
* \param c content of type html
* \param bw browser window
* \param mouse state of mouse buttons and modifier keys
* \param x coordinate of mouse
* \param y coordinate of mouse
*/
void html_mouse_track(struct content *c, struct browser_window *bw,
browser_mouse_state mouse, int x, int y)
{
hlcache_handle *h = bw->current_content;
switch (bw->drag_type) {
case DRAGGING_SELECTION: {
struct box *box;
int dir = -1;
int dx, dy;
if (selection_dragging_start(bw->sel)) dir = 1;
box = box_pick_text_box(h, x, y, dir,
&dx, &dy);
if (box) {
int pixel_offset;
size_t idx;
plot_font_style_t fstyle;
font_plot_style_from_css(box->style, &fstyle);
nsfont.font_position_in_string(&fstyle,
box->text, box->length,
dx, &idx, &pixel_offset);
selection_track(bw->sel, mouse,
box->byte_offset + idx);
}
}
break;
default:
html_mouse_action(c, bw, mouse, x, y);
break;
}
}
/**
* Handle mouse clicks and movements in an HTML content window.
*
* \param c content of type html
* \param bw browser window
* \param mouse state of mouse buttons and modifier keys
* \param x coordinate of mouse
* \param y coordinate of mouse
*
* This function handles both hovering and clicking. It is important that the
* code path is identical (except that hovering doesn't carry out the action),
* so that the status bar reflects exactly what will happen. Having separate
* code paths opens the possibility that an attacker will make the status bar
* show some harmless action where clicking will be harmful.
*/
void html_mouse_action(struct content *c, struct browser_window *bw,
browser_mouse_state mouse, int x, int y)
{
enum { ACTION_NONE, ACTION_SUBMIT, ACTION_GO } action = ACTION_NONE;
char *title = 0;
const char *url = 0;
const char *target = 0;
char status_buffer[200];
const char *status = 0;
gui_pointer_shape pointer = GUI_POINTER_DEFAULT;
bool imagemap = false;
int box_x = 0, box_y = 0;
int gadget_box_x = 0, gadget_box_y = 0;
int text_box_x = 0;
struct box *url_box = 0;
struct box *gadget_box = 0;
struct box *text_box = 0;
hlcache_handle *h = bw->current_content;
struct box *box;
hlcache_handle *content = h;
hlcache_handle *gadget_content = h;
struct form_control *gadget = 0;
hlcache_handle *object = NULL;
struct box *next_box;
struct box *drag_candidate = NULL;
struct scroll *scroll = NULL;
plot_font_style_t fstyle;
int scroll_mouse_x = 0, scroll_mouse_y = 0;
int padding_left, padding_right, padding_top, padding_bottom;
if (bw->visible_select_menu != NULL) {
box = bw->visible_select_menu->box;
box_coords(box, &box_x, &box_y);
box_x -= box->border[LEFT].width;
box_y += box->height + box->border[BOTTOM].width +
box->padding[BOTTOM] + box->padding[TOP];
status = form_select_mouse_action(bw->visible_select_menu,
mouse, x - box_x, y - box_y);
if (status != NULL)
browser_window_set_status(bw, status);
else {
int width, height;
form_select_get_dimensions(bw->visible_select_menu,
&width, &height);
bw->visible_select_menu = NULL;
browser_window_redraw_rect(bw, box_x, box_y,
width, height);
}
return;
}
if (bw->scroll != NULL) {
struct browser_scroll_data *data = scroll_get_data(bw->scroll);
box = data->box;
box_coords(box, &box_x, &box_y);
if (scroll_is_horizontal(bw->scroll)) {
scroll_mouse_x = x - box_x ;
scroll_mouse_y = y - (box_y + box->padding[TOP] +
box->height + box->padding[BOTTOM] -
SCROLLBAR_WIDTH);
status = scroll_mouse_action(bw->scroll, mouse,
scroll_mouse_x, scroll_mouse_y);
} else {
scroll_mouse_x = x - (box_x + box->padding[LEFT] +
box->width + box->padding[RIGHT] -
SCROLLBAR_WIDTH);
scroll_mouse_y = y - box_y;
status = scroll_mouse_action(bw->scroll, mouse,
scroll_mouse_x, scroll_mouse_y);
}
browser_window_set_status(bw, status);
return;
}
bw->drag_type = DRAGGING_NONE;
/* search the box tree for a link, imagemap, form control, or
* box with scrollbars */
box = html_get_box_tree(h);
/* Consider the margins of the html page now */
box_x = box->margin[LEFT];
box_y = box->margin[TOP];
while ((next_box = box_at_point(box, x, y, &box_x, &box_y, &content)) !=
NULL) {
enum css_overflow_e overflow = CSS_OVERFLOW_VISIBLE;
box = next_box;
if (box->style && css_computed_visibility(box->style) ==
CSS_VISIBILITY_HIDDEN)
continue;
if (box->object)
object = box->object;
if (box->href) {
url = box->href;
target = box->target;
url_box = box;
}
if (box->usemap) {
url = imagemap_get(content, box->usemap,
box_x, box_y, x, y, &target);
if (url) {
imagemap = true;
url_box = box;
}
}
if (box->gadget) {
gadget_content = content;
gadget = box->gadget;
gadget_box = box;
gadget_box_x = box_x;
gadget_box_y = box_y;
if (gadget->form)
target = gadget->form->target;
}
if (box->title)
title = box->title;
pointer = get_pointer_shape(bw, box, false);
if (box->style)
overflow = css_computed_overflow(box->style);
if ((box->scroll_x != NULL || box->scroll_y != NULL) &&
drag_candidate == NULL)
drag_candidate = box;
if (box->scroll_y != NULL || box->scroll_x != NULL) {
padding_left = box_x + scroll_get_offset(box->scroll_x);
padding_right = padding_left + box->padding[LEFT] +
box->width + box->padding[RIGHT];
padding_top = box_y + scroll_get_offset(box->scroll_y);
padding_bottom = padding_top + box->padding[TOP] +
box->height + box->padding[BOTTOM];
if (x > padding_left && x < padding_right &&
y > padding_top && y < padding_bottom) {
/* mouse inside padding box */
if (box->scroll_y != NULL && x > padding_right -
SCROLLBAR_WIDTH) {
/* mouse above vertical box scroll */
scroll = box->scroll_y;
scroll_mouse_x = x - (padding_right -
SCROLLBAR_WIDTH);
scroll_mouse_y = y - padding_top;
break;
} else if (box->scroll_x != NULL &&
y > padding_bottom -
SCROLLBAR_WIDTH) {
/* mouse above horizontal box scroll */
scroll = box->scroll_x;
scroll_mouse_x = x - padding_left;
scroll_mouse_y = y - (padding_bottom -
SCROLLBAR_WIDTH);
break;
}
}
}
if (box->text && !box->object) {
text_box = box;
text_box_x = box_x;
}
}
/* use of box_x, box_y, or content below this point is probably a
* mistake; they will refer to the last box returned by box_at_point */
if (scroll) {
status = scroll_mouse_action(scroll, mouse,
scroll_mouse_x, scroll_mouse_y);
pointer = GUI_POINTER_DEFAULT;
} else if (gadget) {
switch (gadget->type) {
case GADGET_SELECT:
status = messages_get("FormSelect");
pointer = GUI_POINTER_MENU;
if (mouse & BROWSER_MOUSE_CLICK_1 &&
option_core_select_menu) {
bw->visible_select_menu = gadget;
form_open_select_menu(bw, gadget,
form_select_menu_callback,
bw);
pointer = GUI_POINTER_DEFAULT;
} else if (mouse & BROWSER_MOUSE_CLICK_1)
gui_create_form_select_menu(bw, gadget);
break;
case GADGET_CHECKBOX:
status = messages_get("FormCheckbox");
if (mouse & BROWSER_MOUSE_CLICK_1) {
gadget->selected = !gadget->selected;
html_redraw_a_box(gadget_content, gadget_box);
}
break;
case GADGET_RADIO:
status = messages_get("FormRadio");
if (mouse & BROWSER_MOUSE_CLICK_1)
form_radio_set(gadget_content, gadget);
break;
case GADGET_IMAGE:
if (mouse & BROWSER_MOUSE_CLICK_1) {
gadget->data.image.mx = x - gadget_box_x;
gadget->data.image.my = y - gadget_box_y;
}
/* drop through */
case GADGET_SUBMIT:
if (gadget->form) {
snprintf(status_buffer, sizeof status_buffer,
messages_get("FormSubmit"),
gadget->form->action);
status = status_buffer;
pointer = get_pointer_shape(bw, gadget_box,
false);
if (mouse & (BROWSER_MOUSE_CLICK_1 |
BROWSER_MOUSE_CLICK_2))
action = ACTION_SUBMIT;
} else {
status = messages_get("FormBadSubmit");
}
break;
case GADGET_TEXTAREA:
status = messages_get("FormTextarea");
pointer = get_pointer_shape(bw, gadget_box, false);
if (mouse & (BROWSER_MOUSE_PRESS_1 |
BROWSER_MOUSE_PRESS_2)) {
if (text_box && selection_root(bw->sel) !=
gadget_box)
selection_init(bw->sel, gadget_box);
browser_window_textarea_click(bw,
mouse,
gadget_box,
gadget_box_x,
gadget_box_y,
x - gadget_box_x,
y - gadget_box_y);
}
if (text_box) {
int pixel_offset;
size_t idx;
font_plot_style_from_css(text_box->style,
&fstyle);
nsfont.font_position_in_string(&fstyle,
text_box->text,
text_box->length,
x - gadget_box_x - text_box->x,
&idx,
&pixel_offset);
selection_click(bw->sel, mouse,
text_box->byte_offset + idx);
if (selection_dragging(bw->sel)) {
bw->drag_type = DRAGGING_SELECTION;
status = messages_get("Selecting");
} else
status = content_get_status_message(h);
}
else if (mouse & BROWSER_MOUSE_PRESS_1)
selection_clear(bw->sel, true);
break;
case GADGET_TEXTBOX:
case GADGET_PASSWORD:
status = messages_get("FormTextbox");
pointer = get_pointer_shape(bw, gadget_box, false);
if ((mouse & BROWSER_MOUSE_PRESS_1) &&
!(mouse & (BROWSER_MOUSE_MOD_1 |
BROWSER_MOUSE_MOD_2))) {
browser_window_input_click(bw,
gadget_box,
gadget_box_x,
gadget_box_y,
x - gadget_box_x,
y - gadget_box_y);
}
if (text_box) {
int pixel_offset;
size_t idx;
if (mouse & (BROWSER_MOUSE_DRAG_1 |
BROWSER_MOUSE_DRAG_2))
selection_init(bw->sel, gadget_box);
font_plot_style_from_css(text_box->style,
&fstyle);
nsfont.font_position_in_string(&fstyle,
text_box->text,
text_box->length,
x - gadget_box_x - text_box->x,
&idx,
&pixel_offset);
selection_click(bw->sel, mouse,
text_box->byte_offset + idx);
if (selection_dragging(bw->sel))
bw->drag_type = DRAGGING_SELECTION;
}
else if (mouse & BROWSER_MOUSE_PRESS_1)
selection_clear(bw->sel, true);
break;
case GADGET_HIDDEN:
/* not possible: no box generated */
break;
case GADGET_RESET:
status = messages_get("FormReset");
break;
case GADGET_FILE:
status = messages_get("FormFile");
break;
case GADGET_BUTTON:
/* This gadget cannot be activated */
status = messages_get("FormButton");
break;
}
} else if (object && (mouse & BROWSER_MOUSE_MOD_2)) {
if (mouse & BROWSER_MOUSE_DRAG_2)
gui_drag_save_object(GUI_SAVE_OBJECT_NATIVE, object,
bw->window);
else if (mouse & BROWSER_MOUSE_DRAG_1)
gui_drag_save_object(GUI_SAVE_OBJECT_ORIG, object,
bw->window);
/* \todo should have a drag-saving object msg */
status = content_get_status_message(h);
} else if (url) {
if (title) {
snprintf(status_buffer, sizeof status_buffer, "%s: %s",
url, title);
status = status_buffer;
} else
status = url;
pointer = get_pointer_shape(bw, url_box, imagemap);
if (mouse & BROWSER_MOUSE_CLICK_1 &&
mouse & BROWSER_MOUSE_MOD_1) {
/* force download of link */
browser_window_go_post(bw, url, 0, 0, false,
content_get_url(h), true, true, 0);
} else if (mouse & BROWSER_MOUSE_CLICK_2 &&
mouse & BROWSER_MOUSE_MOD_1) {
gui_window_save_link(bw->window, url, title);
} else if (mouse & (BROWSER_MOUSE_CLICK_1 |
BROWSER_MOUSE_CLICK_2))
action = ACTION_GO;
} else {
bool done = false;
/* frame resizing */
if (bw->parent) {
struct browser_window *parent;
for (parent = bw->parent; parent->parent;
parent = parent->parent);
browser_window_resize_frames(parent, mouse,
x + bw->x0, y + bw->y0,
&pointer, &status, &done);
}
/* if clicking in the main page, remove the selection from any
* text areas */
if (!done) {
struct box *layout = html_get_box_tree(h);
if (text_box &&
(mouse & (BROWSER_MOUSE_CLICK_1 |
BROWSER_MOUSE_CLICK_2)) &&
selection_root(bw->sel) != layout)
selection_init(bw->sel, layout);
if (text_box) {
int pixel_offset;
size_t idx;
font_plot_style_from_css(text_box->style,
&fstyle);
nsfont.font_position_in_string(&fstyle,
text_box->text,
text_box->length,
x - text_box_x,
&idx,
&pixel_offset);
if (selection_click(bw->sel, mouse,
text_box->byte_offset + idx)) {
/* key presses must be directed at the
* main browser window, paste text
* operations ignored */
if (selection_dragging(bw->sel)) {
bw->drag_type =
DRAGGING_SELECTION;
status =
messages_get("Selecting");
} else
status = content_get_status_message(h);
done = true;
}
}
else if (mouse & BROWSER_MOUSE_PRESS_1)
selection_clear(bw->sel, true);
}
if (!done) {
if (title)
status = title;
else if (bw->loading_content)
status = content_get_status_message(
bw->loading_content);
else
status = content_get_status_message(h);
if (mouse & BROWSER_MOUSE_DRAG_1) {
if (mouse & BROWSER_MOUSE_MOD_2) {
gui_drag_save_object(GUI_SAVE_COMPLETE,
h, bw->window);
} else {
if (drag_candidate == NULL)
browser_window_page_drag_start(
bw, x, y);
else {
html_box_drag_start(
drag_candidate,
x, y);
}
pointer = GUI_POINTER_MOVE;
}
}
else if (mouse & BROWSER_MOUSE_DRAG_2) {
if (mouse & BROWSER_MOUSE_MOD_2) {
gui_drag_save_object(GUI_SAVE_SOURCE,
h, bw->window);
} else {
if (drag_candidate == NULL)
browser_window_page_drag_start(
bw, x, y);
else {
html_box_drag_start(
drag_candidate,
x, y);
}
pointer = GUI_POINTER_MOVE;
}
}
}
if ((mouse & BROWSER_MOUSE_CLICK_1) &&
!selection_defined(bw->sel)) {
/* ensure key presses still act on the browser window */
browser_window_remove_caret(bw);
}
}
if (action == ACTION_SUBMIT || action == ACTION_GO)
bw->last_action = wallclock();
if (status != NULL)
browser_window_set_status(bw, status);
browser_window_set_pointer(bw->window, pointer);
/* deferred actions that can cause this browser_window to be destroyed
* and must therefore be done after set_status/pointer
*/
switch (action) {
case ACTION_SUBMIT:
form_submit(bw->current_content,
browser_window_find_target(bw, target, mouse),
gadget->form, gadget);
break;
case ACTION_GO:
browser_window_go(browser_window_find_target(bw, target, mouse),
url, content_get_url(h), true);
break;
case ACTION_NONE:
break;
}
}
gui_pointer_shape get_pointer_shape(struct browser_window *bw, struct box *box,
bool imagemap)
{
gui_pointer_shape pointer;
css_computed_style *style;
enum css_cursor_e cursor;
lwc_string **cursor_uris;
bool loading;
assert(bw);
loading = (bw->loading_content != NULL || (bw->current_content &&
content_get_status(bw->current_content) ==
CONTENT_STATUS_READY));
if (wallclock() - bw->last_action < 100 && loading)
/* If less than 1 second since last link followed, show
* progress indicating pointer and we're loading something */
return GUI_POINTER_PROGRESS;
if (box->type == BOX_FLOAT_LEFT || box->type == BOX_FLOAT_RIGHT)
style = box->children->style;
else
style = box->style;
if (style == NULL)
return GUI_POINTER_DEFAULT;
cursor = css_computed_cursor(style, &cursor_uris);
switch (cursor) {
case CSS_CURSOR_AUTO:
if (box->href || (box->gadget &&
(box->gadget->type == GADGET_IMAGE ||
box->gadget->type == GADGET_SUBMIT)) ||
imagemap) {
/* link */
pointer = GUI_POINTER_POINT;
} else if (box->gadget &&
(box->gadget->type == GADGET_TEXTBOX ||
box->gadget->type == GADGET_PASSWORD ||
box->gadget->type == GADGET_TEXTAREA)) {
/* text input */
pointer = GUI_POINTER_CARET;
} else {
/* anything else */
if (loading) {
/* loading new content */
pointer = GUI_POINTER_PROGRESS;
} else {
pointer = GUI_POINTER_DEFAULT;
}
}
break;
case CSS_CURSOR_CROSSHAIR:
pointer = GUI_POINTER_CROSS;
break;
case CSS_CURSOR_POINTER:
pointer = GUI_POINTER_POINT;
break;
case CSS_CURSOR_MOVE:
pointer = GUI_POINTER_MOVE;
break;
case CSS_CURSOR_E_RESIZE:
pointer = GUI_POINTER_RIGHT;
break;
case CSS_CURSOR_W_RESIZE:
pointer = GUI_POINTER_LEFT;
break;
case CSS_CURSOR_N_RESIZE:
pointer = GUI_POINTER_UP;
break;
case CSS_CURSOR_S_RESIZE:
pointer = GUI_POINTER_DOWN;
break;
case CSS_CURSOR_NE_RESIZE:
pointer = GUI_POINTER_RU;
break;
case CSS_CURSOR_SW_RESIZE:
pointer = GUI_POINTER_LD;
break;
case CSS_CURSOR_SE_RESIZE:
pointer = GUI_POINTER_RD;
break;
case CSS_CURSOR_NW_RESIZE:
pointer = GUI_POINTER_LU;
break;
case CSS_CURSOR_TEXT:
pointer = GUI_POINTER_CARET;
break;
case CSS_CURSOR_WAIT:
pointer = GUI_POINTER_WAIT;
break;
case CSS_CURSOR_PROGRESS:
pointer = GUI_POINTER_PROGRESS;
break;
case CSS_CURSOR_HELP:
pointer = GUI_POINTER_HELP;
break;
default:
pointer = GUI_POINTER_DEFAULT;
break;
}
return pointer;
}
/**
* Callback for in-page scrolls.
*/
void html_overflow_scroll_callback(void *client_data,
struct scroll_msg_data *scroll_data)
{
struct browser_scroll_data *data = client_data;
struct browser_window *bw = data->bw;
struct box *box = data->box;
int x, y, box_x, box_y, diff_x, diff_y;
switch(scroll_data->msg) {
case SCROLL_MSG_REDRAW:
diff_x = box->padding[LEFT] + box->width +
box->padding[RIGHT] - SCROLLBAR_WIDTH;
diff_y = box->padding[TOP] + box->height +
box->padding[BOTTOM] - SCROLLBAR_WIDTH;
box_coords(box, &box_x, &box_y);
if (scroll_is_horizontal(scroll_data->scroll)) {
x = box_x + scroll_get_offset(box->scroll_x);
y = box_y + scroll_get_offset(box->scroll_y) +
diff_y;
} else {
x = box_x + scroll_get_offset(box->scroll_x) +
diff_x;
y = box_y + scroll_get_offset(box->scroll_y);
}
browser_window_redraw_rect(bw,
x + scroll_data->x0,
y + scroll_data->y0,
scroll_data->x1 - scroll_data->x0,
scroll_data->y1 - scroll_data->y0);
break;
case SCROLL_MSG_MOVED:
html_redraw_a_box(bw->current_content, box);
break;
case SCROLL_MSG_SCROLL_START:
bw->scroll = scroll_data->scroll;
gui_window_box_scroll_start(bw->window,
scroll_data->x0, scroll_data->y0,
scroll_data->x1, scroll_data->y1);
break;
case SCROLL_MSG_SCROLL_FINISHED:
bw->scroll = NULL;
browser_window_set_pointer(bw->window,
GUI_POINTER_DEFAULT);
break;
}
}
/**
* End overflow scroll scrollbar drags
*
* \param scroll scrollbar widget
* \param mouse state of mouse buttons and modifier keys
* \param x coordinate of mouse
* \param y coordinate of mouse
*/
void html_overflow_scroll_drag_end(struct scroll *scroll,
browser_mouse_state mouse, int x, int y)
{
int scroll_mouse_x, scroll_mouse_y, box_x, box_y;
struct browser_scroll_data *data = scroll_get_data(scroll);
struct box *box;
box = data->box;
box_coords(box, &box_x, &box_y);
if (scroll_is_horizontal(scroll)) {
scroll_mouse_x = x - box_x;
scroll_mouse_y = y - (box_y + box->padding[TOP] +
box->height + box->padding[BOTTOM] -
SCROLLBAR_WIDTH);
scroll_mouse_drag_end(scroll, mouse,
scroll_mouse_x, scroll_mouse_y);
} else {
scroll_mouse_x = x - (box_x + box->padding[LEFT] +
box->width + box->padding[RIGHT] -
SCROLLBAR_WIDTH);
scroll_mouse_y = y - box_y;
scroll_mouse_drag_end(scroll, mouse,
scroll_mouse_x, scroll_mouse_y);
}
}
/**
* End overflow scroll scrollbar drags
*
* \param h html content's high level cache entry
* \param mouse state of mouse buttons and modifier keys
* \param x coordinate of mouse
* \param y coordinate of mouse
*/
size_t html_selection_drag_end(hlcache_handle *h, browser_mouse_state mouse,
int x, int y, int dir)
{
int pixel_offset;
struct box *box;
int dx, dy;
size_t idx = 0;
box = box_pick_text_box(h, x, y, dir, &dx, &dy);
if (box) {
plot_font_style_t fstyle;
font_plot_style_from_css(box->style, &fstyle);
nsfont.font_position_in_string(&fstyle, box->text, box->length,
dx, &idx, &pixel_offset);
idx += box->byte_offset;
}
return idx;
}
/**
* Start drag scrolling the contents of a box
*
* \param box the box to be scrolled
* \param x x ordinate of initial mouse position
* \param y y ordinate
*/
void html_box_drag_start(struct box *box, int x, int y)
{
int box_x, box_y, scroll_mouse_x, scroll_mouse_y;
box_coords(box, &box_x, &box_y);
if (box->scroll_x != NULL) {
scroll_mouse_x = x - box_x ;
scroll_mouse_y = y - (box_y + box->padding[TOP] +
box->height + box->padding[BOTTOM] -
SCROLLBAR_WIDTH);
scroll_start_content_drag(box->scroll_x,
scroll_mouse_x, scroll_mouse_y);
} else if (box->scroll_y != NULL) {
scroll_mouse_x = x - (box_x + box->padding[LEFT] +
box->width + box->padding[RIGHT] -
SCROLLBAR_WIDTH);
scroll_mouse_y = y - box_y;
scroll_start_content_drag(box->scroll_y,
scroll_mouse_x, scroll_mouse_y);
}
}