/* GTK - The GIMP Toolkit
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*
* Author: Theppitak Karoonboonyanan <thep@linux.thai.net>
*
*/
#include <string.h>
#include <gdk/gdkkeysyms.h>
#include "gtkimcontextthai.h"
#include "thai-charprop.h"
static void gtk_im_context_thai_class_init (GtkIMContextThaiClass *class);
static void gtk_im_context_thai_init (GtkIMContextThai *im_context_thai);
static gboolean gtk_im_context_thai_filter_keypress (GtkIMContext *context,
GdkEventKey *key);
#ifndef GTK_IM_CONTEXT_THAI_NO_FALLBACK
static void forget_previous_chars (GtkIMContextThai *context_thai);
static void remember_previous_char (GtkIMContextThai *context_thai,
gunichar new_char);
#endif /* !GTK_IM_CONTEXT_THAI_NO_FALLBACK */
static GObjectClass *parent_class;
GType gtk_type_im_context_thai = 0;
void
gtk_im_context_thai_register_type (GTypeModule *type_module)
{
const GTypeInfo im_context_thai_info =
{
sizeof (GtkIMContextThaiClass),
(GBaseInitFunc) NULL,
(GBaseFinalizeFunc) NULL,
(GClassInitFunc) gtk_im_context_thai_class_init,
NULL, /* class_finalize */
NULL, /* class_data */
sizeof (GtkIMContextThai),
0,
(GInstanceInitFunc) gtk_im_context_thai_init,
};
gtk_type_im_context_thai =
g_type_module_register_type (type_module,
GTK_TYPE_IM_CONTEXT,
"GtkIMContextThai",
&im_context_thai_info, 0);
}
static void
gtk_im_context_thai_class_init (GtkIMContextThaiClass *class)
{
GtkIMContextClass *im_context_class = GTK_IM_CONTEXT_CLASS (class);
parent_class = g_type_class_peek_parent (class);
im_context_class->filter_keypress = gtk_im_context_thai_filter_keypress;
}
static void
gtk_im_context_thai_init (GtkIMContextThai *context_thai)
{
#ifndef GTK_IM_CONTEXT_THAI_NO_FALLBACK
forget_previous_chars (context_thai);
#endif /* !GTK_IM_CONTEXT_THAI_NO_FALLBACK */
context_thai->isc_mode = ISC_BASICCHECK;
}
GtkIMContext *
gtk_im_context_thai_new (void)
{
GtkIMContextThai *result;
result = GTK_IM_CONTEXT_THAI (g_object_new (GTK_TYPE_IM_CONTEXT_THAI, NULL));
return GTK_IM_CONTEXT (result);
}
GtkIMContextThaiISCMode
gtk_im_context_thai_get_isc_mode (GtkIMContextThai *context_thai)
{
return context_thai->isc_mode;
}
GtkIMContextThaiISCMode
gtk_im_context_thai_set_isc_mode (GtkIMContextThai *context_thai,
GtkIMContextThaiISCMode mode)
{
GtkIMContextThaiISCMode prev_mode = context_thai->isc_mode;
context_thai->isc_mode = mode;
return prev_mode;
}
static gboolean
is_context_lost_key(guint keyval)
{
return ((keyval & 0xFF00) == 0xFF00) &&
(keyval == GDK_BackSpace ||
keyval == GDK_Tab ||
keyval == GDK_Linefeed ||
keyval == GDK_Clear ||
keyval == GDK_Return ||
keyval == GDK_Pause ||
keyval == GDK_Scroll_Lock ||
keyval == GDK_Sys_Req ||
keyval == GDK_Escape ||
keyval == GDK_Delete ||
(GDK_Home <= keyval && keyval <= GDK_Begin) || /* IsCursorkey */
(GDK_KP_Space <= keyval && keyval <= GDK_KP_Delete) || /* IsKeypadKey, non-chars only */
(GDK_Select <= keyval && keyval <= GDK_Break) || /* IsMiscFunctionKey */
(GDK_F1 <= keyval && keyval <= GDK_F35)); /* IsFunctionKey */
}
static gboolean
is_context_intact_key(guint keyval)
{
return (((keyval & 0xFF00) == 0xFF00) &&
((GDK_Shift_L <= keyval && keyval <= GDK_Hyper_R) || /* IsModifierKey */
(keyval == GDK_Mode_switch) ||
(keyval == GDK_Num_Lock))) ||
(((keyval & 0xFE00) == 0xFE00) &&
(GDK_ISO_Lock <= keyval && keyval <= GDK_ISO_Last_Group_Lock));
}
static gboolean
thai_is_accept (gunichar new_char, gunichar prev_char, gint isc_mode)
{
switch (isc_mode)
{
case ISC_PASSTHROUGH:
return TRUE;
case ISC_BASICCHECK:
return TAC_compose_input (prev_char, new_char) != 'R';
case ISC_STRICT:
{
int op = TAC_compose_input (prev_char, new_char);
return op != 'R' && op != 'S';
}
default:
return FALSE;
}
}
#define thai_is_composible(n,p) (TAC_compose_input ((p), (n)) == 'C')
#ifndef GTK_IM_CONTEXT_THAI_NO_FALLBACK
static void
forget_previous_chars (GtkIMContextThai *context_thai)
{
memset (context_thai->char_buff, 0, sizeof (context_thai->char_buff));
}
static void
remember_previous_char (GtkIMContextThai *context_thai, gunichar new_char)
{
memmove (context_thai->char_buff + 1, context_thai->char_buff,
(GTK_IM_CONTEXT_THAI_BUFF_SIZE - 1) * sizeof (context_thai->char_buff[0]));
context_thai->char_buff[0] = new_char;
}
#endif /* !GTK_IM_CONTEXT_THAI_NO_FALLBACK */
static gunichar
get_previous_char (GtkIMContextThai *context_thai, gint offset)
{
gchar *surrounding;
gint cursor_index;
if (gtk_im_context_get_surrounding ((GtkIMContext *)context_thai,
&surrounding, &cursor_index))
{
gunichar prev_char;
gchar *p, *q;
prev_char = 0;
p = surrounding + cursor_index;
for (q = p; offset < 0 && q > surrounding; ++offset)
q = g_utf8_prev_char (q);
if (offset == 0)
{
prev_char = g_utf8_get_char_validated (q, p - q);
if (prev_char < 0)
prev_char = 0;
}
g_free (surrounding);
return prev_char;
}
#ifndef GTK_IM_CONTEXT_THAI_NO_FALLBACK
else
{
offset = -offset - 1;
if (0 <= offset && offset < GTK_IM_CONTEXT_THAI_BUFF_SIZE)
return context_thai->char_buff[offset];
}
#endif /* !GTK_IM_CONTEXT_THAI_NO_FALLBACK */
return 0;
}
static gboolean
gtk_im_context_thai_commit_chars (GtkIMContextThai *context_thai,
gunichar *s, gsize len)
{
gchar *utf8;
utf8 = g_ucs4_to_utf8 (s, len, NULL, NULL, NULL);
if (!utf8)
return FALSE;
g_signal_emit_by_name (context_thai, "commit", utf8);
g_free (utf8);
return TRUE;
}
static gboolean
accept_input (GtkIMContextThai *context_thai, gunichar new_char)
{
#ifndef GTK_IM_CONTEXT_THAI_NO_FALLBACK
remember_previous_char (context_thai, new_char);
#endif /* !GTK_IM_CONTEXT_THAI_NO_FALLBACK */
return gtk_im_context_thai_commit_chars (context_thai, &new_char, 1);
}
static gboolean
reorder_input (GtkIMContextThai *context_thai,
gunichar prev_char, gunichar new_char)
{
gunichar buf[2];
if (!gtk_im_context_delete_surrounding (GTK_IM_CONTEXT (context_thai), -1, 1))
return FALSE;
#ifndef GTK_IM_CONTEXT_THAI_NO_FALLBACK
forget_previous_chars (context_thai);
remember_previous_char (context_thai, new_char);
remember_previous_char (context_thai, prev_char);
#endif /* !GTK_IM_CONTEXT_THAI_NO_FALLBACK */
buf[0] = new_char;
buf[1] = prev_char;
return gtk_im_context_thai_commit_chars (context_thai, buf, 2);
}
static gboolean
replace_input (GtkIMContextThai *context_thai, gunichar new_char)
{
if (!gtk_im_context_delete_surrounding (GTK_IM_CONTEXT (context_thai), -1, 1))
return FALSE;
#ifndef GTK_IM_CONTEXT_THAI_NO_FALLBACK
forget_previous_chars (context_thai);
remember_previous_char (context_thai, new_char);
#endif /* !GTK_IM_CONTEXT_THAI_NO_FALLBACK */
return gtk_im_context_thai_commit_chars (context_thai, &new_char, 1);
}
static gboolean
gtk_im_context_thai_filter_keypress (GtkIMContext *context,
GdkEventKey *event)
{
GtkIMContextThai *context_thai = GTK_IM_CONTEXT_THAI (context);
gunichar prev_char, new_char;
gboolean is_reject;
GtkIMContextThaiISCMode isc_mode;
if (event->type != GDK_KEY_PRESS)
return FALSE;
if (event->state & (GDK_MODIFIER_MASK
& ~(GDK_SHIFT_MASK | GDK_LOCK_MASK | GDK_MOD2_MASK)) ||
is_context_lost_key (event->keyval))
{
#ifndef GTK_IM_CONTEXT_THAI_NO_FALLBACK
forget_previous_chars (context_thai);
#endif /* !GTK_IM_CONTEXT_THAI_NO_FALLBACK */
return FALSE;
}
if (event->keyval == 0 || is_context_intact_key (event->keyval))
{
return FALSE;
}
prev_char = get_previous_char (context_thai, -1);
if (!prev_char)
prev_char = ' ';
new_char = gdk_keyval_to_unicode (event->keyval);
is_reject = TRUE;
isc_mode = gtk_im_context_thai_get_isc_mode (context_thai);
if (thai_is_accept (new_char, prev_char, isc_mode))
{
accept_input (context_thai, new_char);
is_reject = FALSE;
}
else
{
gunichar context_char;
/* rejected, trying to correct */
context_char = get_previous_char (context_thai, -2);
if (context_char)
{
if (thai_is_composible (new_char, context_char))
{
if (thai_is_composible (prev_char, new_char))
is_reject = !reorder_input (context_thai, prev_char, new_char);
else if (thai_is_composible (prev_char, context_char))
is_reject = !replace_input (context_thai, new_char);
else if ((TAC_char_class (prev_char) == FV1
|| TAC_char_class (prev_char) == AM)
&& TAC_char_class (new_char) == TONE)
is_reject = !reorder_input (context_thai, prev_char, new_char);
}
else if (thai_is_accept (new_char, context_char, isc_mode))
is_reject = !replace_input (context_thai, new_char);
}
}
if (is_reject)
{
/* reject character */
gdk_beep ();
}
return TRUE;
}