gnucash-sheet-private.c

/********************************************************************\
 * This program 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; either version 2 of   *
 * the License, or (at your option) any later version.              *
 *                                                                  *
 * This program 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, contact:                        *
 *                                                                  *
 * Free Software Foundation           Voice:  +1-617-542-5942       *
 * 51 Franklin Street, Fifth Floor    Fax:    +1-617-542-2652       *
 * Boston, MA  02110-1301,  USA       gnu@gnu.org                   *
 *                                                                  *
\********************************************************************/

/*
 * The Gnucash Grid drawing functions
 *
 * The gnucash grid used to be a fully fledged object. However it has no
 * intelligence of its own, so instead I have reduced it to just a complex
 * drawing function.
 * It specializes in drawing the non-editable parts of a gnucash sheet, that is
 * - the rows and columns with proper backgrounds and borders
 * - the text for each cell in the table
 * - dividing lines (red and blue)
 *
 * This could have been addedi directly into gnucash_sheet.c, but is kept
 * separate to not oversize that file.
 */

#include <config.h>

#include <string.h>

#include "gnucash-sheet.h"
#include "gnucash-sheetP.h"
#include "gnucash-color.h"
#include "gnucash-style.h"
#include "gnc-gtk-utils.h"

/*
 * Sets virt_row, virt_col to the block coordinates for the
 * block containing pixel (x, y).  Also sets o_x, o_y, to the
 * pixel coordinates of the origin of the block.  Returns
 * TRUE if a block is found, FALSE if (x,y) is not
 * in any block.
 *
 * All coordinates are with respect to the canvas origin.
 */
static SheetBlock *
find_block_by_pixel (GnucashSheet *sheet,
                     gint x, gint y,
                     VirtualCellLocation *vcell_loc)
{
    SheetBlock *block;
    VirtualCellLocation vc_loc = { 1, 0 };

    g_return_val_if_fail (y >= 0, NULL);
    g_return_val_if_fail (x >= 0, NULL);

    do
    {
        block = gnucash_sheet_get_block (sheet, vc_loc);
        if (!block)
            return NULL;

        if (block->visible &&
                y >= block->origin_y &&
                y < block->origin_y + block->style->dimensions->height)
        {
            if (vcell_loc)
                vcell_loc->virt_row = vc_loc.virt_row;
            break;
        }
        vc_loc.virt_row++;
    }
    while (vc_loc.virt_row < sheet->num_virt_rows);

    if (vc_loc.virt_row == sheet->num_virt_rows)
        return NULL;

    do
    {
        block = gnucash_sheet_get_block (sheet, vc_loc);
        if (!block)
            return NULL;

        if (block->visible &&
                x >= block->origin_x &&
                x < block->origin_x + block->style->dimensions->width)
        {
            if (vcell_loc)
                vcell_loc->virt_col = vc_loc.virt_col;
            break;
        }
        vc_loc.virt_col++;
    }
    while (vc_loc.virt_col < sheet->num_virt_cols);

    if (vc_loc.virt_col == sheet->num_virt_cols)
        return NULL;

    return block;
}

static gboolean
find_cell_by_pixel (GnucashSheet *sheet, gint x, gint y,
                    VirtualLocation *virt_loc)
{
    SheetBlock *block;
    SheetBlockStyle *style;
    CellDimensions *cd;
    gint row = 0;
    gint col = 0;

    g_return_val_if_fail (virt_loc != NULL, FALSE);

    block = gnucash_sheet_get_block (sheet, virt_loc->vcell_loc);
    if (block == NULL)
        return FALSE;

    /* now make x, y relative to the block origin */
    x -= block->origin_x;
    y -= block->origin_y;

    style = block->style;
    if (style == NULL)
        return FALSE;

    do
    {
        cd = gnucash_style_get_cell_dimensions (style, row, 0);

        if (cd && y >= cd->origin_y && y < cd->origin_y + cd->pixel_height)
            break;

        row++;
    }
    while (row < style->nrows);

    if (row == style->nrows)
        return FALSE;

    do
    {
        cd = gnucash_style_get_cell_dimensions (style, row, col);

        if (cd && x >= cd->origin_x && x < cd->origin_x + cd->pixel_width)
            break;

        col++;
    }
    while (col < style->ncols);

    if (col == style->ncols)
        return FALSE;

    if (virt_loc)
        virt_loc->phys_row_offset = row;
    if (virt_loc)
        virt_loc->phys_col_offset = col;

    return TRUE;
}

gboolean
gnucash_sheet_find_loc_by_pixel (GnucashSheet *sheet, gint x, gint y,
                                 VirtualLocation *virt_loc)
{
    SheetBlock *block;

    if (virt_loc == NULL)
        return FALSE;

    block = find_block_by_pixel (sheet, x, y,
            &virt_loc->vcell_loc);
    if (block == NULL)
        return FALSE;

    return find_cell_by_pixel (sheet, x, y, virt_loc);
}

static void
get_cell_borders (GnucashSheet *sheet, VirtualLocation virt_loc,
                  PhysicalCellBorders *borders)
{
    VirtualLocation v_loc;
    PhysicalCellBorders neighbor;

    gnucash_sheet_get_borders (sheet, virt_loc, borders);

    /* top */
    v_loc = virt_loc;
    if (gnc_table_move_vertical_position (sheet->table, &v_loc, -1))
    {
        gnucash_sheet_get_borders (sheet, v_loc, &neighbor);
        borders->top = MAX(borders->top, neighbor.bottom);
    }

    /* bottom */
    v_loc = virt_loc;
    if (gnc_table_move_vertical_position (sheet->table, &v_loc, 1))
    {
        gnucash_sheet_get_borders (sheet, v_loc, &neighbor);
        borders->bottom = MAX(borders->bottom, neighbor.top);
    }

    /* left */
    v_loc = virt_loc;
    v_loc.phys_col_offset--;
    if (gnc_table_virtual_loc_valid (sheet->table, v_loc, TRUE))
    {
        gnucash_sheet_get_borders (sheet, v_loc, &neighbor);
        borders->left = MAX(borders->left, neighbor.right);
    }

    /* right */
    v_loc = virt_loc;
    v_loc.phys_col_offset++;
    if (gnc_table_virtual_loc_valid (sheet->table, v_loc, TRUE))
    {
        gnucash_sheet_get_borders (sheet, v_loc, &neighbor);
        borders->right = MAX(borders->right, neighbor.left);
    }
}


#ifdef READONLY_LINES_WITH_CHANGED_FG_COLOR

static guint8 inc_intensity_byte (guint8 input, int numerator, int denominator)
{
    guint8 result_inv, result;
    guint8 input_inv = 0xff - input;
    result_inv = (input_inv * numerator) / denominator;
    result = 0xff - result_inv;
    return result;
}

static guint32 inc_intensity_10percent (guint32 argb)
{
    guint32 result =
            (inc_intensity_byte ((argb & 0x00FF0000) >> 16, 8, 10) << 16)
            + (inc_intensity_byte ((argb & 0x0000FF00) >> 8, 8, 10) << 8)
            + (inc_intensity_byte (argb & 0x000000FF, 8, 10));
    return result;
}
#endif

/* Actual drawing routines */

static inline void
draw_cell_line (cairo_t *cr, GdkRGBA *bg_color,
                double x1, double y1, double x2, double y2,
                PhysicalCellBorderLineStyle style);

void
draw_cell_line (cairo_t *cr, GdkRGBA *bg_color,
                double x1, double y1, double x2, double y2,
                PhysicalCellBorderLineStyle style)
{
    GdkRGBA *fg_color;

    switch (style)
    {
        case CELL_BORDER_LINE_NONE:
            fg_color = bg_color;
            break;

        case CELL_BORDER_LINE_LIGHT:
            fg_color = &gn_light_gray;
            break;

        case CELL_BORDER_LINE_NORMAL:
        case CELL_BORDER_LINE_HEAVY:
            fg_color = &gn_black;
            break;

        case CELL_BORDER_LINE_HIGHLIGHT:
            fg_color = &gn_red;
            break;

        default:
            return;
    }

    cairo_set_line_width (cr, 1.0);
    cairo_set_source_rgb (cr, fg_color->red, fg_color->green, fg_color->blue);
    cairo_move_to (cr, x1, y1);
    cairo_line_to (cr, x2, y2);
    cairo_stroke (cr);
}

static void
draw_hatching (cairo_t *cr, double x, double y,
               G_GNUC_UNUSED double width, double height)
{
    GdkRGBA *fg_color;
    double h_x = x + 2.5;
    double h_y = y + 2.5;
    double h_size = height / 3 - 1;

    cairo_set_line_width (cr, 1.0);
    fg_color = &gn_light_gray;
    cairo_set_source_rgb (cr, fg_color->red, fg_color->green, fg_color->blue);

    cairo_rectangle (cr, h_x, h_y, h_size, h_size);
    cairo_move_to (cr, h_x, h_y);
    cairo_rel_line_to (cr, h_size, h_size);
    cairo_rel_move_to (cr, -h_size, 0);
    cairo_rel_line_to (cr, h_size, -h_size);
    cairo_stroke (cr);
}

static void
draw_divider_line (cairo_t *cr, VirtualLocation virt_loc,
                   int div_row, int n_phys_rows, GdkRGBA *fg_color,
                   double x, double y, double width, double height)
{
    double offset;
    if (div_row < 0)
        return;

    /* Test if divider line should be drawn before the current row */
    if ((virt_loc.phys_row_offset == 0) &&
        (virt_loc.vcell_loc.virt_row == div_row))
        offset = 0.0;
    /* Test if divider line should be drawn after the current row */
    else if ((virt_loc.phys_row_offset == n_phys_rows - 1) &&
        (virt_loc.vcell_loc.virt_row == div_row - 1))
        offset = height;
    else
        return;

    cairo_set_source_rgb (cr, fg_color->red, fg_color->green, fg_color->blue);

    cairo_set_line_width (cr, 3.0);
    cairo_move_to (cr, x, y - 0.5 + offset);
    cairo_rel_line_to (cr, width, 0);
    cairo_stroke (cr);
}

static void
set_cell_insensitive (GtkStyleContext *stylectxt)
{
    if (!gtk_style_context_has_class (stylectxt, GTK_STYLE_CLASS_BACKGROUND))
        gtk_style_context_set_state (stylectxt, GTK_STATE_FLAG_INSENSITIVE);
}

static void
draw_cell (GnucashSheet *sheet, SheetBlock *block,
           VirtualLocation virt_loc, cairo_t *cr,
           int x, int y, int width, int height)
{
    GncItemEdit *item_edit = GNC_ITEM_EDIT(sheet->item_editor);
    Table *table = sheet->table;
    PhysicalCellBorders borders;
    const char *text;
    PangoLayout *layout;
    PangoContext *context;
    PangoFontDescription *font;
    PangoRectangle logical_rect;
    GdkRGBA *bg_color, *fg_color;
    GdkRectangle rect;
    gboolean hatching;
    guint32 color_type;
    int x_offset;
    GtkStyleContext *stylectxt = gtk_widget_get_style_context (GTK_WIDGET(sheet));
    GdkRGBA color;
    gboolean use_neg_class = TRUE;

    gtk_style_context_save (stylectxt);

    text = gnc_table_get_entry (table, virt_loc);

    // test for any text, if no text we do not want to add gnc-class-negative-numbers
    if (!text || *text == '\0')
        use_neg_class = FALSE;

    // Get the color type and apply the css class
    color_type = gnc_table_get_color (table, virt_loc, &hatching);
    gnucash_get_style_classes (sheet, stylectxt, color_type, use_neg_class);

    if (sheet->read_only)
        set_cell_insensitive (stylectxt);
    else
    {
        if (gtk_style_context_has_class (stylectxt, GTK_STYLE_CLASS_BACKGROUND))
            gtk_style_context_set_state (stylectxt, GTK_STATE_FLAG_NORMAL);
    }

    // Are we in a read-only row? Then make the background color somewhat more grey.
    if ((virt_loc.phys_row_offset < block->style->nrows)
         && (table->model->dividing_row_upper >= 0))
    {
        if (table->model->reverse_sort)
        {
            if ((table->model->blank_trans_row < table->model->dividing_row_upper)
                 && (virt_loc.vcell_loc.virt_row >= table->model->dividing_row_upper))
            {
                set_cell_insensitive (stylectxt); // future trans after blank
            }

            if ((virt_loc.vcell_loc.virt_row >= table->model->dividing_row_upper)
                 && (virt_loc.vcell_loc.virt_row < table->model->blank_trans_row))
            {
                set_cell_insensitive (stylectxt);
            }
        }
        else // normal order
        {
            if (virt_loc.vcell_loc.virt_row < table->model->dividing_row_upper)
                set_cell_insensitive (stylectxt);
        }
    }

    gtk_render_background (stylectxt, cr, x, y, width, height);

    gdk_rgba_parse (&color, "black");
    gnc_style_context_get_background_color (stylectxt, gtk_style_context_get_state (stylectxt),
                                            &color);
    bg_color = &color;

    get_cell_borders (sheet, virt_loc, &borders);

    /* top */
    draw_cell_line (cr, bg_color,
                    (borders.top >= borders.left ? x : x + 1.0),
                    y - 0.5,
                    (borders.top >= borders.right ?
                     x + width : x + width - 1),
                    y - 0.5,
                    borders.top);

    /* bottom */
    draw_cell_line (cr, bg_color,
                    (borders.bottom >= borders.left ? x : x + 1.0),
                    y + height - 0.5,
                    (borders.bottom >= borders.right ?
                     x + width : x + width - 1),
                    y + height - 0.5,
                    borders.bottom);

    /* left */
    draw_cell_line (cr, bg_color,
                    (x == 0 ? x + 0.5 : x - 0.5),
                    (borders.left > borders.top ? y : y),
                    (x == 0 ? x + 0.5 : x - 0.5),
                    (borders.left > borders.bottom ?
                     y + height : y + height),
                    borders.left);

    /* right */
    draw_cell_line (cr, bg_color,
                    x + width - 0.5,
                    (borders.right > borders.top ? y : y),
                    x + width - 0.5,
                    (borders.right > borders.bottom ?
                     y + height : y + height),
                    borders.right);

    if (hatching)
        draw_hatching (cr, x, y, width, height);

    /* dividing line upper (red) */
    fg_color = &gn_red;
    draw_divider_line (cr, virt_loc,
                       table->model->dividing_row_upper, block->style->nrows,
                       fg_color, x, y, width, height);

    /* dividing line (blue) */
    fg_color = &gn_blue;
    draw_divider_line (cr, virt_loc,
                       table->model->dividing_row, block->style->nrows,
                       fg_color, x, y, width, height);

    /* dividing line lower (blue) */
    draw_divider_line (cr, virt_loc,
                       table->model->dividing_row_lower, block->style->nrows,
                       fg_color, x, y, width, height);

    layout = gtk_widget_create_pango_layout (GTK_WIDGET (sheet), text);

    if (gtk_style_context_has_class (stylectxt, GTK_STYLE_CLASS_VIEW))
        gtk_style_context_remove_class (stylectxt, GTK_STYLE_CLASS_VIEW);

    // We don't need word wrap or line wrap
    pango_layout_set_width (layout, -1);
    context = pango_layout_get_context (layout);
    font = pango_font_description_copy (pango_context_get_font_description (context));

#ifdef READONLY_LINES_WITH_CHANGED_FG_COLOR
    // Are we in a read-only row? Then make the foreground color somewhat less black
    if ((virt_loc.phys_row_offset < block->style->nrows)
            && (table->model->dividing_row_upper >= 0)
            && (virt_loc.vcell_loc.virt_row < table->model->dividing_row_upper))
    {
        // Make text color greyed
        gtk_style_context_add_class (stylectxt, "gnc-class-lighter-grey-mix");
    }
#endif

    if ((text != NULL) && (*text != '\0') && g_strcmp0 (PRICE_CELL_TYPE_NAME,
         gnc_table_get_cell_type_name (table, virt_loc)) == 0)
    {
        int text_width;
        int text_border_padding;

        pango_layout_get_pixel_size (layout, &text_width, NULL);

        text_border_padding = gnc_item_edit_get_margin (item_edit, left_right) +
                              gnc_item_edit_get_padding_border (item_edit, left_right);

        if (text_width + text_border_padding > width)
        {
            int pango_width = (width - text_border_padding) * PANGO_SCALE;

            pango_layout_set_width (layout, pango_width); //pango units
            pango_layout_set_ellipsize (layout, PANGO_ELLIPSIZE_END);
        }
    }

    /* If this is the currently open transaction and
       there is no text in this cell */
    if ((table->current_cursor_loc.vcell_loc.virt_row ==
            virt_loc.vcell_loc.virt_row) &&
            (!text || strlen(text) == 0))
    {
        text = gnc_table_get_label (table, virt_loc);
        if ((text == NULL) || (*text == '\0'))
            goto exit;

        // Make text color greyed
        gtk_style_context_add_class (stylectxt, "gnc-class-lighter-grey-mix");

        pango_layout_set_text (layout, text, strlen (text));
        pango_font_description_set_style (font, PANGO_STYLE_ITALIC);
        pango_context_set_font_description (context, font);
    }

    if ((text == NULL) || (*text == '\0'))
    {
        goto exit;
    }

    pango_layout_get_pixel_extents (layout, NULL, &logical_rect);

    gnucash_sheet_set_text_bounds (sheet, &rect, x, y, width, height);

    cairo_save (cr);
    cairo_rectangle (cr, rect.x, rect.y, rect.width, rect.height);
    cairo_clip (cr);

    x_offset = gnucash_sheet_get_text_offset (sheet, virt_loc,
                                              rect.width, logical_rect.width);

    gtk_render_layout (stylectxt, cr, rect.x + x_offset,
                       rect.y + gnc_item_edit_get_padding_border (item_edit, top), layout);

    cairo_restore (cr);

exit:
    pango_font_description_set_style (font, PANGO_STYLE_NORMAL);
    pango_context_set_font_description (context, font);
    pango_font_description_free (font);
    g_object_unref (layout);

    gtk_style_context_restore (stylectxt);
}

static void
draw_block (GnucashSheet *sheet, SheetBlock *block,
            VirtualLocation virt_loc, cairo_t *cr,
            int x, int y, int width, int height)
{
    CellDimensions *cd;
    gint x_paint;
    gint y_paint;
    gint w, h;

    for (virt_loc.phys_row_offset = 0;
            virt_loc.phys_row_offset < block->style->nrows ;
            virt_loc.phys_row_offset++)
    {
        for (virt_loc.phys_col_offset = 0;
                virt_loc.phys_col_offset < block->style->ncols ;
                virt_loc.phys_col_offset++)
        {
            cd = gnucash_style_get_cell_dimensions
                 (block->style,
                  virt_loc.phys_row_offset,
                  virt_loc.phys_col_offset);

            if (!cd) break;

            x_paint = block->origin_x + cd->origin_x - x;
            if (x_paint > width)
                break;

            y_paint = block->origin_y + cd->origin_y - y;
            if (y_paint > height)
                return;

            h = cd->pixel_height;
            w = cd->pixel_width;

            if (w == 0)
                continue;

            if (x_paint + w < 0)
                continue;

            if (y_paint + h < 0)
                continue;

            draw_cell (sheet, block, virt_loc, cr,
                       x_paint, y_paint, w, h);
        }
    }
}

gboolean
gnucash_sheet_draw_internal (GnucashSheet* sheet, cairo_t* cr,
                             GtkAllocation* alloc)
{
    VirtualLocation virt_loc = {{0, 0}, 0, 0};
    SheetBlock *sheet_block;
    int x = 0;
    int y = 0;
    int width = alloc->width;
    int height = alloc->height;
    GtkAdjustment * adj;

    adj = gtk_scrollable_get_hadjustment (GTK_SCROLLABLE(sheet));
    x = (gint) gtk_adjustment_get_value (adj);
    adj = gtk_scrollable_get_vadjustment (GTK_SCROLLABLE(sheet));
    y = (gint) gtk_adjustment_get_value (adj);

    if (x < 0 || y < 0)
        return FALSE;

    /* compute our initial values where we start drawing */
    sheet_block = find_block_by_pixel (sheet, x, y, &virt_loc.vcell_loc);
    if (!sheet_block || !sheet_block->style)
        return FALSE;

    sheet->read_only = gnc_table_model_read_only (sheet->table->model);

    for ( ; virt_loc.vcell_loc.virt_row < sheet->num_virt_rows;
            virt_loc.vcell_loc.virt_row++ )
    {
        while (TRUE)
        {
            sheet_block = gnucash_sheet_get_block (sheet, virt_loc.vcell_loc);

            if (!sheet_block || !sheet_block->style)
                return TRUE;

            if (sheet_block->visible)
                break;

            virt_loc.vcell_loc.virt_row++;
        }

        if (y + height < sheet_block->origin_y)
            return TRUE;

        draw_block (sheet, sheet_block, virt_loc, cr,
                    x, y, width, height);
    }
    return TRUE;
}


void
gnucash_sheet_draw_cursor (GnucashCursor *cursor, cairo_t *cr)
{
    GnucashCursorCell *cc = &(cursor->cell);
    GdkRGBA *fg_color;
    int x = 0;
    int y = 0;
    GtkAdjustment * adj;

    adj = gtk_scrollable_get_hadjustment (GTK_SCROLLABLE(cursor->sheet));
    x = (gint) gtk_adjustment_get_value (adj);
    adj = gtk_scrollable_get_vadjustment (GTK_SCROLLABLE(cursor->sheet));
    y = (gint) gtk_adjustment_get_value (adj);

    fg_color = &gn_black;

   /* draw the rectangle around the entire active virtual row - transaction rows only - double line  */
    cairo_set_source_rgb (cr, fg_color->red, fg_color->green, fg_color->blue);
    if (cursor->x == 0)
        cairo_rectangle (cr, cursor->x - x + 0.5, cursor->y - y - 0.5, cursor->w - 1.0, cursor->h - 2.0);
    else
        cairo_rectangle (cr, cursor->x - x - 0.5, cursor->y - y - 0.5, cursor->w, cursor->h - 2.0);

    cairo_set_line_width (cr, 1.0);
    cairo_stroke (cr);

    // make the bottom line thicker
    cairo_move_to (cr, cursor->x - x + 0.5, cursor->y - y + cursor->h - 3.5);
    cairo_rel_line_to (cr, cursor->w, 0);
    cairo_set_line_width (cr, 1.0);
    cairo_stroke (cr);

    /* draw rectangle around the active cell */
    cairo_set_source_rgb (cr, fg_color->red, fg_color->green, fg_color->blue);
    if (cc->x != 0)
        cairo_rectangle (cr, cc->x - x - 0.5, cursor->y + cc->y - y - 0.5, cc->w, cc->h);
    else
        cairo_rectangle (cr, cc->x - x + 0.5, cursor->y + cc->y - y - 0.5, cc->w - 1.0, cc->h);

    cairo_set_line_width (cr, 1.0);
    cairo_stroke (cr);
}