path: root/widgets/e-table-header-item.c

/*
 * E-table-column-view.c: A canvas item based view of the ETableColumn.
 *
 * Author:
 *   Miguel de Icaza (miguel@gnu.org)
 *
 * Copyright 1999, Helix Code, Inc.
 */
#include <config.h>
#include "e-table-header.h"
#include "e-table-header-item.h"
#include "e-cursors.h"

/* Padding above and below of the string in the header display */
#define PADDING 4

/* Defines the tolerance for proximity of the column division to the cursor position */
#define TOLERANCE 2

#define ETHI_RESIZING(x) ((x)->resize_col != -1)

#define PARENT_OBJECT_TYPE gnome_canvas_item_get_type ()

static GnomeCanvasItemClass *ethi_parent_class;

enum {
    ARG_0,
    ARG_TABLE_HEADER,
    ARG_TABLE_X,
    ARG_TABLE_Y,
    ARG_TABLE_FONTSET
};

static void
ethi_destroy (GtkObject *object)
{
    ETableHeaderItem *ethi = E_TABLE_HEADER_ITEM (object);

    gtk_object_unref (GTK_OBJECT (ethi->eth));
    
    if (GTK_OBJECT_CLASS (ethi_parent_class)->destroy)
        (*GTK_OBJECT_CLASS (ethi_parent_class)->destroy) (object);
}

static void
ethi_update (GnomeCanvasItem *item, double *affine, ArtSVP *clip_path, int flags)
{
    ETableHeaderItem *ethi = E_TABLE_HEADER_ITEM (item);
    
    if (GNOME_CANVAS_ITEM_CLASS (ethi_parent_class)->update)
        (*GNOME_CANVAS_ITEM_CLASS (ethi_parent_class)->update)(item, affine, clip_path, flags);

    item->x1 = ethi->x1;
    item->y1 = ethi->y1;
    item->x2 = ethi->x1 + ethi->width;
    item->y2 = ethi->y1 + ethi->height;

    gnome_canvas_group_child_bounds (GNOME_CANVAS_GROUP (item->parent), item);
}

static void
ethi_font_load (ETableHeaderItem *ethi, char *font)
{
    if (ethi->font)
        gdk_font_unref (ethi->font);
    
    ethi->font = gdk_fontset_load (font);
    if (ethi->font == NULL)
        ethi->font = gdk_font_load ("fixed");
    
    ethi->height = ethi->font->ascent + ethi->font->descent + PADDING;
}

static void
ethi_drop_table_header (ETableHeaderItem *ethi)
{
    GtkObject *header;
    
    if (!ethi->eth)
        return;

    header = GTK_OBJECT (ethi->eth);
    gtk_signal_disconnect (header, ethi->structure_change_id);
    gtk_signal_disconnect (header, ethi->dimension_change_id);

    gtk_object_unref (header);
    ethi->eth = NULL;
    ethi->width = 0;
}

static void 
structure_changed (ETableHeader *header, ETableHeaderItem *ethi)
{
    ethi->width = e_table_header_total_width (header);

    ethi_update (GNOME_CANVAS_ITEM (ethi), NULL, NULL, 0);
}

static void
dimension_changed (ETableHeader *header, int col, ETableHeaderItem *ethi)
{
    ethi->width = e_table_header_total_width (header);

    ethi_update (GNOME_CANVAS_ITEM (ethi), NULL, NULL, 0);
}

static void
ethi_add_table_header (ETableHeaderItem *ethi, ETableHeader *header)
{
    ethi->eth = header;
    gtk_object_ref (GTK_OBJECT (ethi->eth));
    ethi->width = e_table_header_total_width (header);

    ethi->structure_change_id = gtk_signal_connect (
        GTK_OBJECT (header), "structure_change",
        GTK_SIGNAL_FUNC(structure_changed), ethi);
    ethi->dimension_change_id = gtk_signal_connect (
        GTK_OBJECT (header), "dimension_change",
        GTK_SIGNAL_FUNC(dimension_changed), ethi);
}

static void
ethi_set_arg (GtkObject *o, GtkArg *arg, guint arg_id)
{
    GnomeCanvasItem *item;
    ETableHeaderItem *ethi;
    int v;

    item = GNOME_CANVAS_ITEM (o);
    ethi = E_TABLE_HEADER_ITEM (o);

    switch (arg_id){
    case ARG_TABLE_HEADER:
        ethi_drop_table_header (ethi);
        ethi_add_table_header (ethi, GTK_VALUE_POINTER (*arg));
        break;

    case ARG_TABLE_X:
        ethi->x1 = GTK_VALUE_INT (*arg);
        break;

    case ARG_TABLE_Y:
        ethi->y1 = GTK_VALUE_INT (*arg);
        break;

    case ARG_TABLE_FONTSET:
        ethi_font_load (ethi, GTK_VALUE_STRING (*arg));
        break;
        
    }
    ethi_update (item, NULL, NULL, 0);
}

static void
ethi_realize (GnomeCanvasItem *item)
{
    ETableHeaderItem *ethi = E_TABLE_HEADER_ITEM (item);
    GdkWindow *window;
    GdkColor c;
    
    if (GNOME_CANVAS_ITEM_CLASS (ethi_parent_class)-> realize)
        (*GNOME_CANVAS_ITEM_CLASS (ethi_parent_class)->realize)(item);

    window = GTK_WIDGET (item->canvas)->window;

    ethi->gc = gdk_gc_new (window);
    gnome_canvas_get_color (item->canvas, "black", &c);
    gdk_gc_set_foreground (ethi->gc, &c);

    ethi->normal_cursor = gdk_cursor_new (GDK_ARROW);

    if (!ethi->font)
        ethi_font_load (ethi, "fixed");
}

static void
ethi_unrealize (GnomeCanvasItem *item)
{
    ETableHeaderItem *ethi = E_TABLE_HEADER_ITEM (item);
    
    gdk_gc_unref (ethi->gc);
    ethi->gc = NULL;

    gdk_cursor_destroy (ethi->change_cursor);
    ethi->change_cursor = NULL;
    
    gdk_cursor_destroy (ethi->normal_cursor);
    ethi->normal_cursor = NULL;

    if (GNOME_CANVAS_ITEM_CLASS (ethi_parent_class)->unrealize)
        (*GNOME_CANVAS_ITEM_CLASS (ethi_parent_class)->unrealize)(item);
}

static void
draw_button (ETableHeaderItem *ethi, ETableCol *col,
         GdkDrawable *drawable, GdkGC *gc, GtkStyle *style,
         int x, int y, int width, int height)
{
    GdkRectangle clip;
    int xtra;
    
    gdk_draw_rectangle (
        drawable, gc, TRUE,
        x + 1, y + 1, width - 2, height -2);
    
    gtk_draw_shadow (
        style, drawable, 
        GTK_STATE_NORMAL, GTK_SHADOW_OUT,
        x , y, width, height);

    clip.x = x + 2;
    clip.y = y + 2;
    clip.width = width - 4;
    clip.height = ethi->height;
    
    gdk_gc_set_clip_rectangle (ethi->gc, &clip);

    /* Center the thing */
    xtra = (clip.width - gdk_string_measure (ethi->font, col->id))/2;

    if (xtra < 0)
        xtra = 0;
    
    /* Skip over border */
    x += xtra + 2;
    
    gdk_draw_text (
        drawable, ethi->font,
        ethi->gc, x, y + ethi->height - PADDING,
        col->id, strlen (col->id));
}

static void
ethi_draw (GnomeCanvasItem *item, GdkDrawable *drawable, int x1, int y1, int width, int height)
{
    ETableHeaderItem *ethi = E_TABLE_HEADER_ITEM (item);
    GnomeCanvas *canvas = item->canvas;
    GdkGC *gc;
    const int cols = e_table_header_count (ethi->eth);
    int x2 = x1 + width;
    int col, total;
    int x;

    total = 0;
    x = -x1;

#if 0
    printf ("My coords are: %g %g %g %g\n",
        item->x1, item->y1, item->x2, item->y2);
#endif
    
    for (col = 0; col < cols; col++){
        ETableCol *ecol = e_table_header_get_column (ethi->eth, col);
        int col_width;

        if (col == ethi->resize_col)
            col_width = ethi->resize_width;
        else
            col_width = ecol->width;
                
        if (x1 > total + col_width){
            total += col_width;
            x += col_width;
            continue;
        }

        if (x2 < total)
            return;

        gc = GTK_WIDGET (canvas)->style->bg_gc [GTK_STATE_ACTIVE];

        draw_button (ethi, ecol, drawable, gc,
                 GTK_WIDGET (canvas)->style,
                 x, ethi->y1 - y1, col_width, ethi->height);

        x += col_width;
        total += col_width;
    }
}

static double
ethi_point (GnomeCanvasItem *item, double x, double y, int cx, int cy,
        GnomeCanvasItem **actual_item)
{
    *actual_item = item;
    return 0.0;
}

/*
 * is_pointer_on_division:
 *
 * Returns whether @pos is a column header division;  If @the_total is not NULL,
 * then the actual position is returned here.  If @return_ecol is not NULL,
 * then the ETableCol that actually contains this point is returned here
 */
static gboolean
is_pointer_on_division (ETableHeaderItem *ethi, int pos, int *the_total, int *return_col)
{
    const int cols = e_table_header_count (ethi->eth);
    int col, total;

    total = 0;
    for (col = 0; col < cols; col++){
        ETableCol *ecol = e_table_header_get_column (ethi->eth, col);

        total += ecol->width;

        if ((total - TOLERANCE < pos ) && (pos < total + TOLERANCE)){
            if (return_col)
                *return_col = col;
            if (the_total)
                *the_total = total;

            return TRUE;
        }

        if (total > pos + TOLERANCE)
            return FALSE;
    }

    return FALSE;
}

#define convert(c,sx,sy,x,y) gnome_canvas_w2c (c,sx,sy,x,y)

static void
set_cursor (ETableHeaderItem *ethi, int pos)
{
    GtkWidget *canvas = GTK_WIDGET (GNOME_CANVAS_ITEM (ethi)->canvas);
        
    /* We might be invoked before we are realized */
    if (!canvas->window)
        return;

    if (is_pointer_on_division (ethi, pos, NULL, NULL))
        e_cursor_set (canvas->window, E_CURSOR_SIZE_X);
    else
        e_cursor_set (canvas->window, E_CURSOR_ARROW);
}

static void
ethi_request_redraw (ETableHeaderItem *ethi)
{
    GnomeCanvas *canvas = GNOME_CANVAS_ITEM (ethi)->canvas;
    
    /*
     * request a redraw
     */
    gnome_canvas_request_redraw (
        canvas, ethi->x1, ethi->y1, ethi->x1 + ethi->width, ethi->x1 + ethi->height);
}

static void
ethi_end_resize (ETableHeaderItem *ethi, int new_size)
{
    e_table_header_set_size (ethi->eth, ethi->resize_col, new_size);

    ethi->resize_col = -1;
    ethi_request_redraw (ethi);
}

/*
 * Handles the events on the ETableHeaderItem, particularly it handles resizing
 */
static int
ethi_event (GnomeCanvasItem *item, GdkEvent *e)
{
    ETableHeaderItem *ethi = E_TABLE_HEADER_ITEM (item);
    GnomeCanvas *canvas = item->canvas;
    const gboolean resizing = ETHI_RESIZING (ethi);
    int x, y, start, col;
    
    switch (e->type){
    case GDK_ENTER_NOTIFY:
        convert (canvas, e->crossing.x, e->crossing.y, &x, &y);
        set_cursor (ethi, x);
        break;

    case GDK_MOTION_NOTIFY:
        convert (canvas, e->motion.x, e->motion.y, &x, &y);
        if (resizing){
            if (ethi->resize_guide == NULL){
                /* Quick hack until I actually bind the views */
                ethi->resize_guide = GINT_TO_POINTER (1);
                gnome_canvas_item_grab (item,
                            GDK_POINTER_MOTION_MASK |
                            GDK_BUTTON_RELEASE_MASK,
                            e_cursor_get (E_CURSOR_SIZE_X),
                            e->button.time);
            }

            if (x - ethi->resize_start_pos <= 0)
                break;

            ethi_request_redraw (ethi);

            ethi->resize_width = x - ethi->resize_start_pos;
            e_table_header_set_size (ethi->eth, ethi->resize_col, ethi->resize_width);

            ethi_request_redraw (ethi);
        } else
            set_cursor (ethi, x);
        break;
        
    case GDK_BUTTON_PRESS:
        convert (canvas, e->button.x, e->button.y, &x, &y);

        if (is_pointer_on_division (ethi, x, &start, &col)){
            ETableCol *ecol;
            
            /*
             * Record the important bits.
             *
             * By setting resize_pos to a non -1 value,
             * we know that we are being resized (used in the
             * other event handlers).
             */
            ecol = e_table_header_get_column (ethi->eth, col);
            ethi->resize_col = col;
            ethi->resize_width = ecol->width;
            ethi->resize_start_pos = start - ecol->width;
        }
        break;

    case GDK_2BUTTON_PRESS:
        if (!resizing)
            break;

        if (e->button.button != 1)
            break;

        printf ("Resize this guy\n");
        break;
        
    case GDK_BUTTON_RELEASE: {
        gboolean needs_ungrab = FALSE;

        if (ethi->resize_col != -1){
            needs_ungrab = (ethi->resize_guide != NULL);
            ethi_end_resize (ethi, ethi->resize_width);
        }
        if (needs_ungrab)
            gnome_canvas_item_ungrab (item, e->button.time);

        break;
    }
    
    default:
        return FALSE;
    }
    return TRUE;
}

static void
ethi_class_init (GtkObjectClass *object_class)
{
    GnomeCanvasItemClass *item_class = (GnomeCanvasItemClass *) object_class;

    ethi_parent_class = gtk_type_class (PARENT_OBJECT_TYPE);
    
    object_class->destroy = ethi_destroy;
    object_class->set_arg = ethi_set_arg;

    item_class->update      = ethi_update;
    item_class->realize     = ethi_realize;
    item_class->unrealize   = ethi_unrealize;
    item_class->draw        = ethi_draw;
    item_class->point       = ethi_point;
    item_class->event       = ethi_event;
    
    gtk_object_add_arg_type ("ETableHeaderItem::ETableHeader", GTK_TYPE_POINTER,
                 GTK_ARG_WRITABLE, ARG_TABLE_HEADER);
    gtk_object_add_arg_type ("ETableHeaderItem::x", GTK_TYPE_INT,
                 GTK_ARG_WRITABLE, ARG_TABLE_X);
    gtk_object_add_arg_type ("ETableHeaderItem::y", GTK_TYPE_INT,
                 GTK_ARG_WRITABLE, ARG_TABLE_Y);
    gtk_object_add_arg_type ("ETableHeaderItem::fontset", GTK_TYPE_STRING,
                 GTK_ARG_WRITABLE, ARG_TABLE_FONTSET);
}

static void
ethi_init (GnomeCanvasItem *item)
{
    ETableHeaderItem *ethi = E_TABLE_HEADER_ITEM (item);

    ethi->resize_col = -1;

    item->x1 = 0;
    item->y1 = 0;
    item->x2 = 0;
    item->y2 = 0;
}

GtkType
e_table_header_item_get_type (void)
{
    static GtkType type = 0;

    if (!type){
        GtkTypeInfo info = {
            "ETableHeaderItem",
            sizeof (ETableHeaderItem),
            sizeof (ETableHeaderItemClass),
            (GtkClassInitFunc) ethi_class_init,
            (GtkObjectInitFunc) ethi_init,
            NULL, /* reserved 1 */
            NULL, /* reserved 2 */
            (GtkClassInitFunc) NULL
        };

        type = gtk_type_unique (PARENT_OBJECT_TYPE, &info);
    }

    return type;
}