path: root/widgets/text/e-completion-view.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* 
 * e-completion-view.c - A text completion selection widget
 * Copyright 2000, 2001, Ximian, Inc.
 *
 * Authors:
 *   Miguel de Icaza <miguel@ximian.com>
 *   Adapted by Jon Trowbridge <trow@ximian.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License, version 2, as published by the Free Software Foundation.
 *
 * 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library 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.
 */

#include <config.h>

#include "e-completion-view.h"

#include <math.h>
#include <gdk/gdkkeysyms.h>
#include <gal/e-table/e-table-simple.h>
#include <gal/e-table/e-table-scrolled.h>
#include <gal/util/e-i18n.h>
#include "gal/util/e-marshal.h"

enum {
    E_COMPLETION_VIEW_NONEMPTY,
    E_COMPLETION_VIEW_ADDED,
    E_COMPLETION_VIEW_FULL,
    E_COMPLETION_VIEW_BROWSE,
    E_COMPLETION_VIEW_UNBROWSE,
    E_COMPLETION_VIEW_ACTIVATE,
    E_COMPLETION_VIEW_LAST_SIGNAL
};

static guint e_completion_view_signals[E_COMPLETION_VIEW_LAST_SIGNAL] = { 0 };

static void    e_completion_view_disconnect     (ECompletionView *cv);
static ETable *e_completion_view_table          (ECompletionView *cv);
static void    e_completion_view_clear_choices  (ECompletionView *cv);
static void    e_completion_view_set_cursor_row (ECompletionView *cv, gint r);
static void    e_completion_view_select         (ECompletionView *cv, gint r);

static gint    e_completion_view_key_press_handler (GtkWidget *w, GdkEventKey *key_event, gpointer user_data);

static void    e_completion_view_class_init (ECompletionViewClass *klass);
static void    e_completion_view_init       (ECompletionView *completion);
static void    e_completion_view_dispose    (GObject *object);

#define PARENT_TYPE GTK_TYPE_EVENT_BOX
static GtkObjectClass *parent_class;



static gint
e_completion_view_local_key_press_handler (GtkWidget *w, GdkEventKey *ev)
{
    return e_completion_view_key_press_handler (w, ev, w);
}

static void
e_completion_view_paint (GtkWidget *widget, GdkRectangle *area)
{
    gint i;

    g_return_if_fail (widget != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (widget));
    g_return_if_fail (area != NULL);

    if (!GTK_WIDGET_DRAWABLE (widget))
        return;

    for (i = 0; i < E_COMPLETION_VIEW (widget)->border_width; ++i) {

        gdk_draw_rectangle (widget->window,
                    widget->style->black_gc,
                    FALSE, i, i, 
                    widget->allocation.width-1-2*i,
                    widget->allocation.height-1-2*i);

    }
    
}

#if 0
static void
e_completion_view_draw (GtkWidget *widget, GdkRectangle *area)
{
    GtkBin *bin;
    GdkRectangle child_area;

    g_return_if_fail (widget != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (widget));
    g_return_if_fail (area != NULL);

    if (GTK_WIDGET_DRAWABLE (widget)) {
        bin = GTK_BIN (widget);

        e_completion_view_paint (widget, area);

        if (bin->child && gtk_widget_intersect (bin->child, area, &child_area))
            gtk_widget_draw (bin->child, &child_area);
    }
}
#endif

static gint
e_completion_view_expose_event (GtkWidget *widget, GdkEventExpose *event)             
{
    GtkBin *bin;
    GdkEventExpose child_event;

    g_return_val_if_fail (widget != NULL, FALSE);
    g_return_val_if_fail (E_IS_COMPLETION_VIEW (widget), FALSE);
    g_return_val_if_fail (event != NULL, FALSE);

    if (GTK_WIDGET_DRAWABLE (widget)) {
        bin = GTK_BIN (widget);

        e_completion_view_paint (widget, &event->area);

        child_event = *event;
        if (bin->child &&
            GTK_WIDGET_NO_WINDOW (bin->child) &&
            gtk_widget_intersect (bin->child, &event->area, &child_event.area))
            gtk_widget_send_expose (bin->child, (GdkEvent*) &child_event);
    }

    return FALSE;
}

static void
e_completion_view_size_request (GtkWidget *widget, GtkRequisition *requisition)
{
    GtkBin *bin;

    g_return_if_fail (widget != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (widget));
    g_return_if_fail (requisition != NULL);

    bin = GTK_BIN (widget);
    
    requisition->width  = 2 * E_COMPLETION_VIEW (widget)->border_width;
    requisition->height = 2 * E_COMPLETION_VIEW (widget)->border_width;

    if (bin->child && GTK_WIDGET_VISIBLE (bin->child)) {
        GtkRequisition child_requisition;
        
        gtk_widget_size_request (bin->child, &child_requisition);
        
        requisition->width += child_requisition.width;
        requisition->height += child_requisition.height;
    }
}

static void
e_completion_view_size_allocate (GtkWidget *widget, GtkAllocation *allocation)               
{
    GtkBin *bin;
    GtkAllocation child_allocation;

    g_return_if_fail (widget != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (widget));
    g_return_if_fail (allocation != NULL);

    bin = GTK_BIN (widget);
    widget->allocation = *allocation;

    child_allocation.x = E_COMPLETION_VIEW (widget)->border_width;
    child_allocation.width = MAX(0, (gint)allocation->width - child_allocation.x * 2);

    child_allocation.y = E_COMPLETION_VIEW (widget)->border_width;
    child_allocation.height = MAX (0, (gint)allocation->height - child_allocation.y * 2);

    if (GTK_WIDGET_REALIZED (widget)) {
        gdk_window_move_resize (widget->window,
                    allocation->x,
                    allocation->y,
                    allocation->width,
                    allocation->height);
    }
    
    if (bin->child) {
        gtk_widget_size_allocate (bin->child, &child_allocation);
    }
}

E_MAKE_TYPE (e_completion_view,
         "ECompletionView",
         ECompletionView,
         e_completion_view_class_init,
         e_completion_view_init,
         PARENT_TYPE)
         
static void
e_completion_view_class_init (ECompletionViewClass *klass)
{
    GObjectClass *object_class = (GObjectClass *) klass;
    GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (klass);

    parent_class = g_type_class_ref (PARENT_TYPE);

    e_completion_view_signals[E_COMPLETION_VIEW_NONEMPTY] =
        g_signal_new ("nonempty",
                  G_OBJECT_CLASS_TYPE (object_class),
                  G_SIGNAL_RUN_LAST,
                  G_STRUCT_OFFSET (ECompletionViewClass, nonempty),
                  NULL, NULL,
                  e_marshal_NONE__NONE,
                  G_TYPE_NONE, 0);

    e_completion_view_signals[E_COMPLETION_VIEW_ADDED] =
        g_signal_new ("added",
                  G_OBJECT_CLASS_TYPE (object_class),
                  G_SIGNAL_RUN_LAST,
                  G_STRUCT_OFFSET (ECompletionViewClass, added),
                  NULL, NULL,
                  e_marshal_NONE__NONE,
                  G_TYPE_NONE, 0);

    e_completion_view_signals[E_COMPLETION_VIEW_FULL] =
        g_signal_new ("full",
                  G_OBJECT_CLASS_TYPE (object_class),
                  G_SIGNAL_RUN_LAST,
                  G_STRUCT_OFFSET (ECompletionViewClass, full),
                  NULL, NULL,
                  e_marshal_NONE__NONE,
                  G_TYPE_NONE, 0);

    e_completion_view_signals[E_COMPLETION_VIEW_BROWSE] =
        g_signal_new ("browse",
                  G_OBJECT_CLASS_TYPE (object_class),
                  G_SIGNAL_RUN_LAST,
                  G_STRUCT_OFFSET (ECompletionViewClass, browse),
                  NULL, NULL,
                  e_marshal_NONE__POINTER,
                  G_TYPE_NONE, 1,
                  G_TYPE_POINTER);

    e_completion_view_signals[E_COMPLETION_VIEW_UNBROWSE] =
        g_signal_new ("unbrowse",
                  G_OBJECT_CLASS_TYPE (object_class),
                  G_SIGNAL_RUN_LAST,
                  G_STRUCT_OFFSET (ECompletionViewClass, unbrowse),
                  NULL, NULL,
                  e_marshal_NONE__NONE,
                  G_TYPE_NONE, 0);

    e_completion_view_signals[E_COMPLETION_VIEW_ACTIVATE] =
        g_signal_new ("activate",
                  G_OBJECT_CLASS_TYPE (object_class),
                  G_SIGNAL_RUN_LAST,
                  G_STRUCT_OFFSET (ECompletionViewClass, activate),
                  NULL, NULL,
                  e_marshal_NONE__POINTER,
                  G_TYPE_NONE, 1,
                  G_TYPE_POINTER);

    object_class->dispose = e_completion_view_dispose;

    widget_class->key_press_event = e_completion_view_local_key_press_handler;
    widget_class->expose_event = e_completion_view_expose_event;
    widget_class->size_request = e_completion_view_size_request;
    widget_class->size_allocate = e_completion_view_size_allocate;
}

static void
e_completion_view_init (ECompletionView *completion)
{
    completion->border_width = 2;
    completion->choices = g_ptr_array_new ();
}

static void
e_completion_view_dispose (GObject *object)
{
    ECompletionView *cv = E_COMPLETION_VIEW (object);

    e_completion_view_disconnect (cv);

    if (cv->choices) {
        e_completion_view_clear_choices (cv);

        g_ptr_array_free (cv->choices, TRUE);
        cv->choices = NULL;
    }

    if (cv->key_widget) {
        g_signal_handler_disconnect (cv->key_widget, cv->key_signal_id);
        g_object_unref (cv->key_widget);
        cv->key_widget = NULL;
    }

    if (cv->completion)
        g_object_unref (cv->completion);
    cv->completion = NULL;

    if (G_OBJECT_CLASS (parent_class)->dispose)
        (G_OBJECT_CLASS (parent_class)->dispose) (object);
}

static void
e_completion_view_disconnect (ECompletionView *cv)
{
    g_return_if_fail (cv != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (cv));

    if (cv->begin_signal_id)
        g_signal_handler_disconnect (cv->completion, cv->begin_signal_id);
    if (cv->comp_signal_id)
        g_signal_handler_disconnect (cv->completion, cv->comp_signal_id);
    if (cv->restart_signal_id)
        g_signal_handler_disconnect (cv->completion, cv->restart_signal_id);
    if (cv->cancel_signal_id)
        g_signal_handler_disconnect (cv->completion, cv->cancel_signal_id);
    if (cv->end_signal_id)
        g_signal_handler_disconnect (cv->completion, cv->end_signal_id);
    if (cv->clear_signal_id)
        g_signal_handler_disconnect (cv->completion, cv->clear_signal_id);
    if (cv->lost_signal_id)
        g_signal_handler_disconnect (cv->completion, cv->lost_signal_id);

    cv->begin_signal_id   = 0;
    cv->comp_signal_id    = 0;
    cv->restart_signal_id = 0;
    cv->cancel_signal_id   = 0;
    cv->end_signal_id     = 0;
    cv->clear_signal_id   = 0;
    cv->lost_signal_id    = 0;
}

static ETable *
e_completion_view_table (ECompletionView *cv)
{
    return e_table_scrolled_get_table (E_TABLE_SCROLLED (cv->table));
}

static void
e_completion_view_clear_choices (ECompletionView *cv)
{
    ECompletionMatch *match;
    GPtrArray *m;
    int i;

    g_return_if_fail (E_IS_COMPLETION_VIEW (cv));

    m = cv->choices;
    for (i = 0; i < m->len; i++) {
        match = g_ptr_array_index (m, i);
        e_completion_match_unref (match);
    }
    g_ptr_array_set_size (m, 0);
}

static void
e_completion_view_set_cursor_row (ECompletionView *cv, gint r)
{
    ETable *table;
    GtkAdjustment *adj;
    gint x, y1, y2, r1, r2, c;
    double fracline;
    gint iteration_count=0;

    g_return_if_fail (cv != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (cv));
#ifndef G_DISABLE_CHECKS
    /* choices->len is unsigned, but it is reasonable for r to be
     * < 0 */
    if (r > 0) {
        g_return_if_fail (r < cv->choices->len);
    }
#endif

    adj = gtk_scrolled_window_get_vadjustment (GTK_SCROLLED_WINDOW (cv->table));    

    table = e_completion_view_table (cv);

    if (r < 0) {
        e_selection_model_clear (E_SELECTION_MODEL(table->selection));
        
        /* Move back to the top when we clear the selection */
        gtk_adjustment_set_value (adj, adj->lower);
        return;
    }

    e_table_set_cursor_row (table, r);

    /* OK, now the tricky bit.  We try to insure that this row is
       visible. */
    
    /* If we are selecting the first or last row, then it is easy.  We just
       cram the vadjustment all the way up/down. */
    if (r == 0) {
        gtk_adjustment_set_value (adj, adj->lower);
        return;
    } else if (r == cv->choices->len - 1) {     
        gtk_adjustment_set_value (adj, adj->upper - adj->page_size);
        return;
    }
    
    fracline = ((adj->upper - adj->lower - adj->page_size) / (gint)cv->choices->len) / 4;

    while (iteration_count < 100) {
        x = GTK_LAYOUT(table->table_canvas)->hadjustment->value;
        y1 = GTK_LAYOUT(table->table_canvas)->vadjustment->value;
        
        y2 = y1 + cv->table->allocation.height;
        
        e_table_group_compute_location (e_completion_view_table (cv)->group, &x, &y1, &r1, &c);
        e_table_group_compute_location (e_completion_view_table (cv)->group, &x, &y2, &r2, &c);
    
        if (r <= r1) {
            gtk_adjustment_set_value (adj, adj->value - fracline);
        } else if (r >= r2) {
            gtk_adjustment_set_value (adj, adj->value + fracline);
        } else 
            return;

        ++iteration_count;
    }

    g_assert_not_reached ();
}

static void
e_completion_view_select (ECompletionView *cv, gint r)
{
    ECompletionMatch *match;

    match = g_ptr_array_index (cv->choices, r);

    cv->selection = r;
    e_completion_view_set_cursor_row (cv, r);
    g_signal_emit (cv, e_completion_view_signals[E_COMPLETION_VIEW_ACTIVATE], 0, match);
}

static gint
e_completion_view_key_press_handler (GtkWidget *w, GdkEventKey *key_event, gpointer user_data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (user_data);
    gint dir = 0;
    gboolean key_handled = TRUE, complete_key = FALSE, uncomplete_key = FALSE, is_space = FALSE;

    /* FIXME: This is totally lame.
       The ECompletionView should be able to specify multiple completion/uncompletion keys, or just
       have sensible defaults. */
    
    if ((cv->complete_key && key_event->keyval == cv->complete_key)
        || ((key_event->keyval == GDK_n || key_event->keyval == GDK_N) && (key_event->state & GDK_CONTROL_MASK)))
        complete_key = TRUE;

    if ((cv->uncomplete_key && key_event->keyval == cv->uncomplete_key)
        || ((key_event->keyval == GDK_p || key_event->keyval == GDK_P) && (key_event->state & GDK_CONTROL_MASK)))
        uncomplete_key = TRUE;
    
    /* Start up a completion.*/
    if (complete_key && !cv->editable) {
        g_signal_emit (cv, e_completion_view_signals[E_COMPLETION_VIEW_BROWSE], 0, NULL);
        goto stop_emission;
    }

    /* Stop our completion. */
    if (uncomplete_key && cv->editable && cv->selection < 0) {
        e_completion_view_set_cursor_row (cv, -1);
        g_signal_emit (cv, e_completion_view_signals[E_COMPLETION_VIEW_UNBROWSE], 0);
        goto stop_emission;
    }

    if (!cv->editable)
        return FALSE;

    switch (key_event->keyval) {

    case GDK_n:
    case GDK_N:
        /* We (heart) emacs: treat ctrl-n as down */
        if (! (key_event->state & GDK_CONTROL_MASK))
            return FALSE;

    case GDK_Down:
    case GDK_KP_Down:
        dir = 1;
        break;

    case GDK_p:
    case GDK_P:
        /* Treat ctrl-p as up */
        if (! (key_event->state & GDK_CONTROL_MASK))
            return FALSE;
        
    case GDK_Up:
    case GDK_KP_Up:
        dir = -1;
        break;
        
    case GDK_Tab:
        /* If our cursor is still up in the entry, move down into
           the popup.  Otherwise unbrowse. */
        if (cv->choices->len > 0) {
            if (cv->selection < 0) {
                cv->selection = 0;
                dir = 0;
            } else {
                cv->selection = -1;
                dir = 0;
                key_handled = FALSE;
            }
        }
        break;

    case GDK_space:
    case GDK_KP_Space:
        is_space = TRUE;

    case GDK_Return:
    case GDK_KP_Enter:
        if (cv->selection < 0) {
            /* We don't have a selection yet, move to the first selection if there is
               more than one option.  If there is only one option, select it automatically. */

            /* Let space pass through. */
            if (is_space)
                return FALSE;
            
            if (cv->choices->len == 1) {
                e_completion_view_select (cv, 0);
                goto stop_emission;
            } else {
                cv->selection = 0;
                dir = 0;
            }

        } else {
            /* Our cursor is down in the pop-up, so we make our selection. */
            e_completion_view_select (cv, cv->selection);
            goto stop_emission;
        }
        break;

    case GDK_Escape:
        /* Unbrowse hack */
        cv->selection = -1;
        dir = 0;
        break;

    default:
        return FALSE;
    }

    cv->selection += dir;

    if (cv->selection >= (int)cv->choices->len) {
        cv->selection = cv->choices->len - 1;
        /* Don't re-emit the browse signal */
        goto stop_emission;
    }

    e_completion_view_set_cursor_row (cv, cv->selection);

    if (cv->selection >= 0)
        g_signal_emit (cv, e_completion_view_signals[E_COMPLETION_VIEW_BROWSE], 0,
                   g_ptr_array_index (cv->choices, cv->selection));
    else
        g_signal_emit (cv, e_completion_view_signals[E_COMPLETION_VIEW_UNBROWSE], 0);

 stop_emission:
    
    if (key_handled)
        g_signal_stop_emission_by_name (w, "key_press_event");

    return key_handled;
}

static void
begin_completion_cb (ECompletion *completion, const gchar *txt, gint pos, gint limit, gpointer user_data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (user_data);

    e_table_model_pre_change (cv->model);
    e_completion_view_clear_choices (cv);
    cv->have_all_choices = FALSE;

    e_table_model_changed (cv->model);
}

static void
restart_completion_cb (ECompletion *completion, gpointer user_data)
{
    /* For now, handle restarts like the beginning of a new completion. */
    begin_completion_cb (completion, NULL, 0, 0, user_data);
}

static void
cancel_completion_cb (ECompletion *completion, gpointer user_data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (user_data);

    /* On a cancel, clear our choices and issue an "unbrowse" signal. */
    e_table_model_pre_change (cv->model);
    e_completion_view_clear_choices (cv);
    cv->have_all_choices = TRUE;
    e_completion_view_set_cursor_row (cv, -1);
    e_table_model_changed (cv->model);

    g_signal_emit (cv, e_completion_view_signals[E_COMPLETION_VIEW_UNBROWSE] ,0);
}

static void
completion_cb (ECompletion *completion, ECompletionMatch *match, gpointer user_data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (user_data);
    gint r = cv->choices->len;
    gboolean first = (cv->choices->len == 0);

    e_table_model_pre_change (cv->model);

    e_completion_match_ref (match);
    g_ptr_array_add (cv->choices, match);

    e_table_model_row_inserted (cv->model, r);

    if (first)
        g_signal_emit (cv, e_completion_view_signals[E_COMPLETION_VIEW_NONEMPTY], 0);

    g_signal_emit (cv, e_completion_view_signals[E_COMPLETION_VIEW_ADDED], 0);
}

static void
end_completion_cb (ECompletion *completion, gpointer user_data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (user_data);

    /* Do a final refresh of the table. */
    e_table_model_pre_change (cv->model);
    e_table_model_changed (cv->model);

    cv->have_all_choices = TRUE;
    g_signal_emit (cv, e_completion_view_signals[E_COMPLETION_VIEW_FULL], 0);
}

static void
clear_completion_cb (ECompletion *completion, gpointer user_data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (user_data);

    e_table_model_pre_change (cv->model);
    e_completion_view_clear_choices (cv);
    cv->have_all_choices = FALSE;

    e_table_model_changed (cv->model);
}

static void
lost_completion_cb (ECompletion *completion, ECompletionMatch *match, gpointer user_data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (user_data);
    int i;
    GPtrArray *c = cv->choices;

    for (i = 0; i < c->len; i++)
        if (g_ptr_array_index (c, i) == match)
            break;

    g_return_if_fail (i == c->len);

    /* FIXME: do remove_index_fast(), then row_changed and
     * row_deleted (if there are more than 1 row still) */
    e_table_model_pre_change (cv->model);
    g_ptr_array_remove_index (c, i);
    e_table_model_row_deleted (cv->model, i);
    
    e_completion_match_unref (match);
}

/*** Table Callbacks ***/

static char *simple_spec = 
"<ETableSpecification no-headers=\"true\" draw-grid=\"false\" cursor-mode=\"line\" alternating-row-colors=\"false\" gettext-domain=\"" E_I18N_DOMAIN "\">"
"  <ETableColumn model_col=\"0\" _title=\"Node\" expansion=\"1.0\" "
"         minimum_width=\"16\" resizable=\"true\" cell=\"string\" "
"         compare=\"string\"/> "
"       <ETableState>                  "
"           <column source=\"0\"/> "
"           <grouping></grouping>  "
"        </ETableState>                "
"</ETableSpecification>";

static gint
table_col_count (ETableModel *etm, gpointer data)
{
    return 1;
}

static gint
table_row_count (ETableModel *etm, gpointer data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (data);
    return cv->choices->len;
}

static gboolean
table_is_cell_editable (ETableModel *etm, gint c, gint r, gpointer data)
{
    return FALSE;
}

static gpointer
table_value_at (ETableModel *etm, gint c, gint r, gpointer data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (data);
    ECompletionMatch *match;

    match = g_ptr_array_index (cv->choices, r);

    return (gpointer) e_completion_match_get_menu_text (match);
}

static gchar *
table_value_to_string (ETableModel *em, gint col, gconstpointer val, gpointer data)
{
    return (gchar *) val;
}

static void
table_click_cb (ETable *et, gint r, gint c, GdkEvent *ev, gpointer data)
{
    ECompletionView *cv = E_COMPLETION_VIEW (data);

    e_completion_view_select (cv, r);
}

void
e_completion_view_construct (ECompletionView *cv, ECompletion *completion)
{
    g_return_if_fail (cv != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (cv));
    g_return_if_fail (completion != NULL);
    g_return_if_fail (E_IS_COMPLETION (completion));

    /* Make sure we don't call construct twice. */
    g_return_if_fail (cv->completion == NULL);

    GTK_WIDGET_SET_FLAGS (GTK_WIDGET (cv), GTK_CAN_FOCUS);

    cv->completion = completion;
    g_object_ref (completion);

    cv->begin_signal_id   = g_signal_connect (completion,
                          "begin_completion",
                          G_CALLBACK (begin_completion_cb),
                          cv);
    cv->comp_signal_id    = g_signal_connect (completion,
                          "completion",
                          G_CALLBACK (completion_cb),
                          cv);
    cv->restart_signal_id = g_signal_connect (completion,
                          "restart_completion",
                          G_CALLBACK (restart_completion_cb),
                          cv);
    cv->cancel_signal_id  = g_signal_connect (completion,
                          "cancel_completion",
                          G_CALLBACK (cancel_completion_cb),
                          cv);
    cv->end_signal_id     = g_signal_connect (completion,
                          "end_completion",
                          G_CALLBACK (end_completion_cb),
                          cv);
    cv->clear_signal_id   = g_signal_connect (completion,
                          "clear_completion",
                          G_CALLBACK (clear_completion_cb),
                          cv);
    cv->lost_signal_id    = g_signal_connect (completion,
                          "lost_completion",
                          G_CALLBACK (lost_completion_cb),
                          cv);

    cv->model = e_table_simple_new (table_col_count,
                    table_row_count,
                    NULL,

                    table_value_at,
                    NULL,
                    table_is_cell_editable,

                    NULL, NULL,

                    NULL, NULL, NULL, NULL,
                    table_value_to_string,
                    cv);

    cv->table = e_table_scrolled_new (cv->model, NULL, simple_spec, NULL);
    g_object_unref (cv->model);

    gtk_scrolled_window_set_shadow_type (GTK_SCROLLED_WINDOW (cv->table), GTK_SHADOW_NONE);
    gtk_scrolled_window_set_policy (GTK_SCROLLED_WINDOW (cv->table), GTK_POLICY_NEVER, GTK_POLICY_AUTOMATIC);

    gtk_container_add (GTK_CONTAINER (cv), cv->table);
    gtk_widget_show_all (cv->table);

    g_signal_connect (e_completion_view_table (cv),
              "click",
              G_CALLBACK (table_click_cb),
              cv);

    cv->selection = -1;
}

GtkWidget *
e_completion_view_new (ECompletion *completion)
{
    gpointer p;

    g_return_val_if_fail (completion != NULL, NULL);
    g_return_val_if_fail (E_IS_COMPLETION (completion), NULL);

    p = g_object_new (E_COMPLETION_VIEW_TYPE, NULL);

    e_completion_view_construct (E_COMPLETION_VIEW (p), completion);

    return GTK_WIDGET (p);
}

void
e_completion_view_connect_keys (ECompletionView *cv, GtkWidget *w)
{
    g_return_if_fail (cv != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (cv));
    g_return_if_fail (w == NULL || GTK_IS_WIDGET (w));

    if (cv->key_widget) {
        g_signal_handler_disconnect (cv->key_widget, cv->key_signal_id);
        g_object_unref (cv->key_widget);
    }

    if (w) {
        cv->key_widget = w;
        g_object_ref (w);

        cv->key_signal_id = g_signal_connect (w,
                              "key_press_event",
                              G_CALLBACK (e_completion_view_key_press_handler),
                              cv);
    } else {
        cv->key_widget = NULL;
        cv->key_signal_id = 0;
    }
}

void
e_completion_view_set_complete_key (ECompletionView *cv, gint keyval)
{
    g_return_if_fail (cv != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (cv));

    cv->complete_key = keyval;
}

void
e_completion_view_set_uncomplete_key (ECompletionView *cv, gint keyval)
{
    g_return_if_fail (cv != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (cv));

    cv->uncomplete_key = keyval;
}

void
e_completion_view_set_width (ECompletionView *cv, gint width)
{
    GtkWidget *w;
    gint y, r, dummy, line_height, final_height;
    double drop_room, lines;

    g_return_if_fail (cv != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (cv));
    g_return_if_fail (width > 0);

    w = GTK_WIDGET (cv);

    if (! GTK_WIDGET_REALIZED (w)) {
        gtk_widget_set_usize (w, width, -1);
        return;
    }

    /* A Horrible Hack(tm) to figure out the height of a single table row */
    
    for (line_height=5, r=0; r == 0 && line_height < 1000; line_height += 2) {
        dummy = 0;
        e_table_group_compute_location (e_completion_view_table (cv)->group,
                        &dummy, &line_height, &r, &dummy);
    }

    if (line_height >= 1000) {
        /* Something went wrong, so we make a (possibly very lame) guess */
        line_height = 30;
    }


    gdk_window_get_origin (w->window, NULL, &y);
    y += w->allocation.y;

    lines = 5; /* default maximum */
    lines = MIN (lines, cv->choices->len);
    
    drop_room = (gdk_screen_height () - y) / (double)line_height;
    drop_room = MAX (drop_room, 1);

    lines = MIN (lines, drop_room);

    /* We reduce the total height by a bit; in practice, this seems to work out well. */
    final_height = (gint) floor (line_height * (0.5 + (float)lines) * 0.97);
    gtk_widget_set_usize (w, width, final_height);
}

void
e_completion_view_set_editable (ECompletionView *cv, gboolean x)
{
    g_return_if_fail (cv != NULL);
    g_return_if_fail (E_IS_COMPLETION_VIEW (cv));

    if (x == cv->editable)
        return;

    cv->editable = x;
    cv->selection = -1;
    e_completion_view_set_cursor_row (cv, -1);
}