path: root/widgets/table/e-table-selection-model.c

/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
 * e-table-selection-model.c: a Table Selection Model
 *
 * Author:
 *   Miguel de Icaza (miguel@gnu.org)
 *
 * (C) 1999 Helix Code, Inc.
 */
#include <config.h>
#include <gtk/gtksignal.h>
#include "e-table-selection-model.h"
#include "e-util/e-util.h"

#define ETSM_CLASS(e) ((ETableSelectionModelClass *)((GtkObject *)e)->klass)

#define PARENT_TYPE gtk_object_get_type ()

#define ONES ((guint32) 0xffffffff)

#define BOX(n) ((n) / 32)
#define OFFSET(n) (31 - ((n) % 32))
#define BITMASK(n) (((guint32) 0x1) << OFFSET(n))
#define BITMASK_LEFT(n) (((guint32) ONES) << (32 - ((n) % 32)))
#define BITMASK_RIGHT(n) (((guint32) ONES) >> ((n) % 32))

static GtkObjectClass *e_table_selection_model_parent_class;

enum {
    CURSOR_CHANGED,
    SELECTION_CHANGED,
    LAST_SIGNAL
};

static guint e_table_selection_model_signals [LAST_SIGNAL] = { 0, };

enum {
    ARG_0,
    ARG_MODEL,
    ARG_CURSOR_ROW,
    ARG_CURSOR_COL,
};

static void
model_changed(ETableModel *etm, ETableSelectionModel *etsm)
{
    g_free(etsm->selection);
    etsm->selection = NULL;
    etsm->row_count = -1;
    gtk_signal_emit(GTK_OBJECT(etsm),
            e_table_selection_model_signals [SELECTION_CHANGED]);
}

#if 1
static void
model_row_inserted(ETableModel *etm, int row, ETableSelectionModel *etsm)
{
    int box;
    int i;
    if(etsm->row_count >= 0) {
        /* Add another word if needed. */
        if ((etsm->row_count & 0x1f) == 0) {
            etsm->selection = g_realloc(etsm->selection, (etsm->row_count >> 5) + 1);
            etsm->selection[etsm->row_count >> 5] = 0;
        }

        /* The box is the word that our row is in. */
        box = BOX(row);
        /* Shift all words to the right of our box right one bit. */
        for (i = etsm->row_count >> 5; i > box; i--) {
            etsm->selection[i] = (etsm->selection[i] >> 1) | (etsm->selection[i - 1] << 31);
        }

        /* Shift right half of box one bit to the right. */
        etsm->selection[box] = (etsm->selection[box] & BITMASK_LEFT(row)) | ((etsm->selection[box] & BITMASK_RIGHT(row)) >> 1);
        etsm->row_count ++;
    }
}

static void
model_row_deleted(ETableModel *etm, int row, ETableSelectionModel *etsm)
{
    int box;
    int i;
    int last;
    if(etsm->row_count >= 0) {
        guint32 bitmask;
        box = row >> 5;
        last = etsm->row_count >> 5;

        /* Build bitmasks for the left and right half of the box */
        bitmask = BITMASK_RIGHT(row) >> 1;
        /* Shift right half of box one bit to the left. */
        etsm->selection[box] = (etsm->selection[box] & BITMASK_LEFT(row))| ((etsm->selection[box] & bitmask) << 1);

        /* Shift all words to the right of our box left one bit. */
        if (box < last) {
            etsm->selection[box] &= etsm->selection[box + 1] >> 31;

            for (i = box + 1; i < last; i++) {
                etsm->selection[i] = (etsm->selection[i] << 1) | (etsm->selection[i + 1] >> 31);
            }
            etsm->selection[i] = etsm->selection[i] << 1;
        }
        etsm->row_count --;
        /* Remove the last word if not needed. */
        if ((etsm->row_count & 0x1f) == 0) {
            etsm->selection = g_realloc(etsm->selection, etsm->row_count >> 5);
        }
    }
}

#else

static void
model_row_inserted(ETableModel *etm, int row, ETableSelectionModel *etsm)
{
    model_changed(etm, etsm);
}

static void
model_row_deleted(ETableModel *etm, int row, ETableSelectionModel *etsm)
{
    model_changed(etm, etsm);
}
#endif

inline static void
add_model(ETableSelectionModel *etsm, ETableModel *model)
{
    etsm->model = model;
    if (model) {
        gtk_object_ref(GTK_OBJECT(model));
        etsm->model_changed_id = gtk_signal_connect(GTK_OBJECT(model), "model_changed",
                                GTK_SIGNAL_FUNC(model_changed), etsm);
        etsm->model_row_inserted_id = gtk_signal_connect(GTK_OBJECT(model), "model_row_inserted",
                                 GTK_SIGNAL_FUNC(model_row_inserted), etsm);
        etsm->model_row_deleted_id = gtk_signal_connect(GTK_OBJECT(model), "model_row_deleted",
                                GTK_SIGNAL_FUNC(model_row_deleted), etsm);
    }
}

inline static void
drop_model(ETableSelectionModel *etsm)
{
    if (etsm->model) {
        gtk_signal_disconnect(GTK_OBJECT(etsm->model),
                      etsm->model_changed_id);
        gtk_signal_disconnect(GTK_OBJECT(etsm->model),
                      etsm->model_row_inserted_id);
        gtk_signal_disconnect(GTK_OBJECT(etsm->model),
                      etsm->model_row_deleted_id);
        gtk_object_unref(GTK_OBJECT(etsm->model));
    }
    etsm->model = NULL;
}

static void
etsm_destroy (GtkObject *object)
{
    ETableSelectionModel *etsm;

    etsm = E_TABLE_SELECTION_MODEL (object);

    drop_model(etsm);

    g_free(etsm->selection);
}

static void
etsm_get_arg (GtkObject *o, GtkArg *arg, guint arg_id)
{
    ETableSelectionModel *etsm = E_TABLE_SELECTION_MODEL (o);

    switch (arg_id){
    case ARG_MODEL:
        GTK_VALUE_OBJECT (*arg) = GTK_OBJECT(etsm->model);
        break;

    case ARG_CURSOR_ROW:
        GTK_VALUE_INT(*arg) = etsm->cursor_row;
        break;

    case ARG_CURSOR_COL:
        GTK_VALUE_INT(*arg) = etsm->cursor_col;
        break;
    }
}

static void
etsm_set_arg (GtkObject *o, GtkArg *arg, guint arg_id)
{
    ETableSelectionModel *etsm = E_TABLE_SELECTION_MODEL (o);
    
    switch (arg_id){
    case ARG_MODEL:
        drop_model(etsm);
        add_model(etsm, GTK_VALUE_OBJECT (*arg) ? E_TABLE_MODEL(GTK_VALUE_OBJECT (*arg)) : NULL);
        break;

    case ARG_CURSOR_ROW:
        e_table_selection_model_do_something(etsm, GTK_VALUE_INT(*arg), etsm->cursor_col, FALSE, FALSE);
        break;

    case ARG_CURSOR_COL:
        e_table_selection_model_do_something(etsm, etsm->cursor_row, GTK_VALUE_INT(*arg), FALSE, FALSE);
        break;
    }
}

static void
e_table_selection_model_init (ETableSelectionModel *selection)
{
    selection->selection = NULL;
    selection->row_count = -1;
    selection->model = NULL;
}

static void
e_table_selection_model_class_init (ETableSelectionModelClass *klass)
{
    GtkObjectClass *object_class;

    e_table_selection_model_parent_class = gtk_type_class (gtk_object_get_type ());

    object_class = GTK_OBJECT_CLASS(klass);

    object_class->destroy = etsm_destroy;
    object_class->get_arg = etsm_get_arg;
    object_class->set_arg = etsm_set_arg;

    e_table_selection_model_signals [CURSOR_CHANGED] =
        gtk_signal_new ("cursor_changed",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ETableSelectionModelClass, cursor_changed),
                gtk_marshal_NONE__INT_INT,
                GTK_TYPE_NONE, 2, GTK_TYPE_INT, GTK_TYPE_INT);

    e_table_selection_model_signals [SELECTION_CHANGED] =
        gtk_signal_new ("selection_changed",
                GTK_RUN_LAST,
                object_class->type,
                GTK_SIGNAL_OFFSET (ETableSelectionModelClass, selection_changed),
                gtk_marshal_NONE__NONE,
                GTK_TYPE_NONE, 0);

    klass->cursor_changed = NULL;
    klass->selection_changed = NULL;

    gtk_object_class_add_signals (object_class, e_table_selection_model_signals, LAST_SIGNAL);

    gtk_object_add_arg_type ("ETableSelectionModel::model", GTK_TYPE_OBJECT,
                 GTK_ARG_READWRITE, ARG_MODEL);
    gtk_object_add_arg_type ("ETableSelectionModel::cursor_row", GTK_TYPE_INT,
                 GTK_ARG_READWRITE, ARG_CURSOR_ROW);
    gtk_object_add_arg_type ("ETableSelectionModel::cursor_col", GTK_TYPE_INT,
                 GTK_ARG_READWRITE, ARG_CURSOR_COL);
}

E_MAKE_TYPE(e_table_selection_model, "ETableSelectionModel", ETableSelectionModel,
        e_table_selection_model_class_init, e_table_selection_model_init, PARENT_TYPE);

ETableSelectionModel *
e_table_selection_model_new (void)
{
    return gtk_type_new (e_table_selection_model_get_type ());
}

gboolean
e_table_selection_model_is_row_selected (ETableSelectionModel *selection,
                     gint                 n)
{
    if (selection->row_count < n)
        return 0;
    else
        return (selection->selection[BOX(n)] >> OFFSET(n)) & 0x1;
}

void 
e_table_selection_model_foreach     (ETableSelectionModel *selection,
                     ETableForeachFunc callback,
                     gpointer closure)
{
    int i;
    int last = (selection->row_count + 31) / 32;
    for (i = 0; i < last; i++) {
        if (selection->selection[i]) {
            int j;
            guint32 value = selection->selection[i];
            for (j = 0; j < 32; j++) {
                if (value & 0x80000000) {
                    callback(i * 32 + j, closure);
                }
                value <<= 1;
            }
        }
    }
}

#define OPERATE(object, mask, grow) ((grow) ? ((object) |= ~(mask)) : ((object) &= (mask)))

void             e_table_selection_model_do_something      (ETableSelectionModel *selection,
                                guint                 row,
                                guint                 col,
                                gboolean              shift_p,
                                gboolean              ctrl_p)
{
    if (selection->row_count < 0) {
        if (selection->model) {
            selection->row_count = e_table_model_row_count(selection->model);
            g_free(selection->selection);
            selection->selection = g_new0(gint, (selection->row_count + 31) / 32);
        }
    }
    if (selection->row_count >= 0 && row < selection->row_count) {
        if (shift_p) {
            int grow_selection;
            int i;
            int last;
            int first_row;
            int last_row;
            if ((selection->selection_start_row < row && row <= selection->cursor_row) ||
                (selection->selection_start_row >= row && row >= selection->cursor_row)) {
                /* In this case, the selection is shrinking. */
                grow_selection = FALSE;
            } else if ((selection->selection_start_row <= selection->cursor_row && selection->cursor_row <= row) ||
                   (selection->selection_start_row >  selection->cursor_row && selection->cursor_row >= row)) {
                /* In this case, the selection is growing. */
                grow_selection = TRUE;
            } else {
                /* In this case the selection is changing direction.  Ick.  Screw it. */
                return;
            }
            first_row = MIN(selection->cursor_row, row);
            last_row = MAX(selection->cursor_row, row) + 1;
            if (first_row != last_row) {
                i = BOX(first_row);
                last = BOX(last_row);
                
                if (i == last) {
                    OPERATE(selection->selection[i], BITMASK_LEFT(first_row) | BITMASK_RIGHT(last_row), grow_selection);
                } else {
                    OPERATE(selection->selection[i], BITMASK_LEFT(first_row), grow_selection);
                    for (i ++; i < last; i++)
                        if (grow_selection)
                            selection->selection[i] = ONES;
                        else
                            selection->selection[i] = 0;
                    OPERATE(selection->selection[i], BITMASK_RIGHT(last_row), grow_selection);
                }
                gtk_signal_emit(GTK_OBJECT(selection),
                        e_table_selection_model_signals [SELECTION_CHANGED]);
            }
        } else {
            if (ctrl_p) {
                if (selection->selection[BOX(row)] & BITMASK(row))
                    selection->selection[BOX(row)] &= ~BITMASK(row);
                else
                    selection->selection[BOX(row)] |= BITMASK(row);
                gtk_signal_emit(GTK_OBJECT(selection),
                        e_table_selection_model_signals [SELECTION_CHANGED]);
            } else {
                int i;
                for (i = 0; i < ((selection->row_count + 31) / 32); i++) {
                    if (!((i == BOX(row) && selection->selection[i] == BITMASK(row)) ||
                          (i != BOX(row) && selection->selection[i] == 0))) {
                        g_free(selection->selection);
                        selection->selection = g_new0(gint, (selection->row_count + 31) / 32);
                        selection->selection[BOX(row)] = BITMASK(row);

                        gtk_signal_emit(GTK_OBJECT(selection),
                                e_table_selection_model_signals [SELECTION_CHANGED]);
                        break;
                    }
                }
            }
            selection->selection_start_row = row;
        }
        if (selection->cursor_row != row ||
            selection->cursor_col != col) {
            gtk_signal_emit(GTK_OBJECT(selection),
                    e_table_selection_model_signals[CURSOR_CHANGED], row, col);
            selection->cursor_row = row;
            selection->cursor_col = col;
        }
    }
}