Add proper support for when a combobox widget has options that are 2-element arrays

The list box and combo box can have values that are 2-element arrays.  The first element
is the "export" value and the second element is the value that should be shown
in the list box UI.  This fix ensures that we get the proper value to show in the UI.
Also, it adds the option to get the export values.   These are needed if you wish to
update the field dictionary's V (value) entry, which is the currently selected values(s).
This fix works well with gsview.  The other viewers will now display the proper content
in their UI, (unlike before this fix) but may need a bit more work to ensure that the
proper V (value) is updated with changes in the selections.  In addition, we add
selection rectangles to the selected list box items.

2 files changed, 261 insertions, 10 deletions

diff --git a/source/pdf/pdf-appearance.c b/source/pdf/pdf-appearance.c
index b0fa2207..cd1f0f93 100644
--- a/source/pdf/pdf-appearance.c
+++ b/source/pdf/pdf-appearance.c
@@ -9,6 +9,9 @@
 #define UNDERLINE_HEIGHT (0.075f)
 #define LINE_THICKNESS (0.07f)
 #define SMALL_FLOAT (0.00001)
+#define LIST_SEL_COLOR_R (0.6)
+#define LIST_SEL_COLOR_G (0.75)
+#define LIST_SEL_COLOR_B (0.85)
 
 enum
 {
@@ -258,6 +261,38 @@ static void fzbuf_print_color(fz_context *ctx, fz_buffer *fzbuf, pdf_obj *arr, i
 	}
 }
 
+static void fzbuf_print_rect_fill(fz_context *ctx, fz_buffer *fzbuf, const fz_rect *clip,
+	float col[4], int col_size, const fz_matrix *tm, const fz_rect *rect)
+{
+	if (clip)
+	{
+		fz_buffer_printf(ctx, fzbuf, fmt_re, clip->x0, clip->y0, clip->x1 - clip->x0, clip->y1 - clip->y0);
+		fz_buffer_printf(ctx, fzbuf, fmt_W);
+	}
+	if (col_size > 0)
+	{
+		switch (col_size)
+		{
+		case 1:
+			fz_buffer_printf(ctx, fzbuf, "%f g\n", col[0]);
+			break;
+		case 3:
+			fz_buffer_printf(ctx, fzbuf, "%f %f %f rg\n", col[0], col[1], col[2]);
+			break;
+		case 4:
+			fz_buffer_printf(ctx, fzbuf, "%f %f %f %f k\n", col[0], col[1], col[2], col[3]);
+			break;
+		default:
+			break;
+		}
+	}
+	if (tm)
+		fz_buffer_printf(ctx, fzbuf, fmt_Tm, tm->a, tm->b, tm->c, tm->d, tm->e, tm->f);
+
+	fz_buffer_printf(ctx, fzbuf, fmt_re, rect->x0, rect->y0, rect->x1 - rect->x0, rect->y1 - rect->y0);
+	fz_buffer_printf(ctx, fzbuf, fmt_f);
+}
+
 static void fzbuf_print_text(fz_context *ctx, fz_buffer *fzbuf, const fz_rect *clip, pdf_obj *col, font_info *font_rec, const fz_matrix *tm, char *text)
 {
 	fz_buffer_printf(ctx, fzbuf, fmt_q);
@@ -521,7 +556,7 @@ static void text_splitter_retry(text_splitter *splitter)
 	}
 }
 
-static void fzbuf_print_text_start(fz_context *ctx, fz_buffer *fzbuf, const fz_rect *clip, pdf_obj *col, font_info *font, const fz_matrix *tm)
+static void fzbuf_print_text_start1(fz_context *ctx, fz_buffer *fzbuf, const fz_rect *clip, pdf_obj *col)
 {
 	fz_buffer_printf(ctx, fzbuf, fmt_Tx_BMC);
 	fz_buffer_printf(ctx, fzbuf, fmt_q);
@@ -540,7 +575,10 @@ static void fzbuf_print_text_start(fz_context *ctx, fz_buffer *fzbuf, const fz_r
 			fz_buffer_printf(ctx, fzbuf, fmt_n);
 		}
 	}
+}
 
+static void fzbuf_print_text_start2(fz_context *ctx, fz_buffer *fzbuf, font_info *font, const fz_matrix *tm)
+{
 	fz_buffer_printf(ctx, fzbuf, fmt_BT);
 
 	pdf_fzbuf_print_da(ctx, fzbuf, &font->da_rec);
@@ -662,7 +700,8 @@ static fz_buffer *create_text_appearance(fz_context *ctx, pdf_document *doc, con
 			tm.e = rect.x0;
 			tm.f = rect.y1 - (1.0+ascent-descent)*fontsize*splitter.scale/2.0;
 
-			fzbuf_print_text_start(ctx, fzbuf, &rect, info->col, &info->font_rec, &tm);
+			fzbuf_print_text_start1(ctx, fzbuf, &rect, info->col);
+			fzbuf_print_text_start2(ctx, fzbuf, &info->font_rec, &tm);
 
 			fz_buffer_cat(ctx, fzbuf, fztmp);
 
@@ -679,7 +718,8 @@ static fz_buffer *create_text_appearance(fz_context *ctx, pdf_document *doc, con
 
 			fzbuf = fz_new_buffer(ctx, 0);
 
-			fzbuf_print_text_start(ctx, fzbuf, &rect, info->col, &info->font_rec, &tm);
+			fzbuf_print_text_start1(ctx, fzbuf, &rect, info->col);
+			fzbuf_print_text_start2(ctx, fzbuf, &info->font_rec, &tm);
 
 			for (i = 0; i < n; i++)
 				fzbuf_print_text_word(ctx, fzbuf, i == 0 ? init_skip : comb_width, 0.0, text+i, 1);
@@ -1134,6 +1174,208 @@ void pdf_update_text_appearance(fz_context *ctx, pdf_document *doc, pdf_obj *obj
 	}
 }
 
+void pdf_update_listbox_appearance(fz_context *ctx, pdf_document *doc, pdf_obj *obj)
+{
+	text_widget_info info;
+	pdf_xobject *form = NULL;
+	fz_buffer *fzbuf = NULL;
+	fz_matrix tm;
+	fz_rect clip_rect;
+	fz_rect fill_rect;
+	int has_tm;
+	pdf_obj *valarr;
+	pdf_obj *optarr;
+	char *text;
+	int n, m, i, j;
+	char **opts = NULL;
+	char **vals = NULL;
+	int *sel_indices = NULL;
+	char **pos;
+	char *val_sel;
+	int index = -1;
+	float height, width;
+	float ascent, descent, lineheight;
+	int variable;
+	int fontsize;
+	float items_height;
+	fz_rect bbox;
+	int num_sel = 0;
+	int found_count;
+	int val_opt_ok = 1;
+	float color[4];
+
+	memset(&info, 0, sizeof(info));
+
+	fz_var(info);
+	fz_var(form);
+	fz_var(fzbuf);
+	fz_var(opts);
+	fz_var(vals);
+	fz_var(sel_indices);
+	fz_try(ctx)
+	{
+		optarr = pdf_dict_get(ctx, obj, PDF_NAME_Opt);
+		n = pdf_array_len(ctx, optarr);
+		opts = (char **)fz_malloc(ctx, n * sizeof(*opts));
+		vals = (char **)fz_malloc(ctx, n * sizeof(*vals));
+		sel_indices = (int*)fz_malloc(ctx, n * sizeof(int));
+		for (i = 0; i < n; i++)
+		{
+			m = pdf_array_len(ctx, pdf_array_get(ctx, optarr, i));
+			if (m == 2)
+			{
+				vals[i] = pdf_to_str_buf(ctx, pdf_array_get(ctx, pdf_array_get(ctx, optarr, i), 0));
+				opts[i] = pdf_to_str_buf(ctx, pdf_array_get(ctx, pdf_array_get(ctx, optarr, i), 1));
+			}
+			else
+			{
+				opts[i] = pdf_to_str_buf(ctx, pdf_array_get(ctx, optarr, i));
+				val_opt_ok = 0;
+			}
+		}
+
+		/* If ANY of the entries are not an array then just use the opts not
+		   the vals. */
+		if (val_opt_ok)
+			pos = vals;
+		else
+			pos = opts;
+
+		get_text_widget_info(ctx, doc, obj, &info);
+		form = load_or_create_form(ctx, doc, obj, &clip_rect);
+		has_tm = get_matrix(ctx, doc, form, info.q, &tm);
+
+		/* See which ones are selected */
+		valarr = pdf_get_inheritable(ctx, doc, obj, PDF_NAME_V);
+		if (pdf_is_array(ctx, valarr))
+		{
+			num_sel = pdf_array_len(ctx, valarr);
+			/* Multiple selected */
+			found_count = 0;
+			for (i = 0; i < num_sel; i++)
+			{
+				text = pdf_to_str_buf(ctx, pdf_array_get(ctx, valarr, i));
+				/* See if we can find it. */
+				index = -1;
+				for (j = 0; j < n; j++)
+				{
+					if (!strcmp(text, pos[j]))
+					{
+						index = j;
+						break;
+					}
+				}
+				if (index > -1)
+				{
+					sel_indices[found_count] = index;
+					found_count += 1;
+				}
+			}
+			num_sel = found_count;
+		}
+		else
+		{
+			/* One or none selected */
+			text = pdf_to_str_buf(ctx, valarr);
+			num_sel = 0;
+			if (text)
+			{
+				index = -1;
+				for (i = 0; i < n; i++)
+				{
+					if (!strcmp(text, pos[i]))
+					{
+						index = i;
+						break;
+					}
+				}
+				if (index > -1)
+				{
+					num_sel = 1;
+					sel_indices[0] = index;
+				}
+			}
+		}
+
+		if (clip_rect.x1 - clip_rect.x0 > 3.0 && clip_rect.y1 - clip_rect.y0 > 3.0)
+		{
+			clip_rect.x0 += 1.0;
+			clip_rect.x1 -= 1.0;
+			clip_rect.y0 += 1.0;
+			clip_rect.y1 -= 1.0;
+		}
+		height = clip_rect.y1 - clip_rect.y0;
+		width = clip_rect.x1 - clip_rect.x0;
+		variable = (info.font_rec.da_rec.font_size == 0);
+		fontsize = variable
+			? (info.multiline ? 14.0 : height / info.font_rec.lineheight)
+			: info.font_rec.da_rec.font_size;
+
+		/* Get the ascent, descent across the items list. */
+		ascent = 0;
+		descent = 0;
+		info.font_rec.da_rec.font_size = 1;
+		for (i = 0; i < n; i++)
+		{
+			measure_text(ctx, doc, &(info.font_rec), &fz_identity, opts[i], &bbox);
+			descent = fz_min(-bbox.y0, descent);
+			ascent = fz_max(bbox.y1, ascent);
+		}
+		info.font_rec.da_rec.font_size = fontsize;
+		lineheight = ascent - descent;
+
+		/* Check if all items will fit.  If not, then place the "selected" item
+		   at the top of our widget rect. */
+		items_height = n * fontsize * lineheight;
+		if (items_height <= height || !num_sel)
+			fz_translate(&tm, clip_rect.x0, clip_rect.y1 - lineheight * fontsize);
+		else
+			fz_translate(&tm, clip_rect.x0, clip_rect.y1 + (sel_indices[0] - 1) * lineheight * fontsize);
+
+		fzbuf = fz_new_buffer(ctx, 0);
+		/* Start the marked content */
+		fzbuf_print_text_start1(ctx, fzbuf, &clip_rect, NULL);
+		/* Add the selection rects */
+		if (num_sel > 0)
+		{
+			color[0] = LIST_SEL_COLOR_R;
+			color[1] = LIST_SEL_COLOR_G;
+			color[2] = LIST_SEL_COLOR_B;
+			fill_rect.x0 = 0.0;
+			fill_rect.x1 = width;
+			for (i = 0; i < num_sel; i++)
+			{
+				fill_rect.y0 = height - fontsize * lineheight * (sel_indices[i] + 1);
+				fill_rect.y1 = fill_rect.y0 + lineheight * fontsize;
+				fzbuf_print_rect_fill(ctx, fzbuf, NULL, color, 3, NULL, &fill_rect);
+			}
+		}
+		/* Continue with text related details */
+		fzbuf_print_text_start2(ctx, fzbuf, &info.font_rec, &tm);
+		/* And now finish with the text content */
+		for (i = 0; i < n; i++)
+		{
+			fzbuf_print_text_word(ctx, fzbuf, 0.0, i == 0 ? 0 : -fontsize *
+				lineheight, opts[i], strlen(opts[i]));
+		}
+		fzbuf_print_text_end(ctx, fzbuf);
+		update_marked_content(ctx, doc, form, fzbuf);
+	}
+	fz_always(ctx)
+	{
+		fz_free(ctx, opts);
+		fz_free(ctx, vals);
+		fz_free(ctx, sel_indices);
+		pdf_drop_xobject(ctx, form);
+		fz_drop_buffer(ctx, fzbuf);
+		font_info_fin(ctx, &info.font_rec);
+	}
+	fz_catch(ctx)
+	{
+		fz_warn(ctx, "update_text_appearance failed");
+	}
+}
+
 void pdf_update_combobox_appearance(fz_context *ctx, pdf_document *doc, pdf_obj *obj)
 {
 	text_widget_info info;
@@ -2234,9 +2476,9 @@ void pdf_update_appearance(fz_context *ctx, pdf_document *doc, pdf_annot *annot)
 				pdf_update_pushbutton_appearance(ctx, doc, obj);
 				break;
 			case PDF_WIDGET_TYPE_LISTBOX:
+				pdf_update_listbox_appearance(ctx, doc, obj);
+				break;
 			case PDF_WIDGET_TYPE_COMBOBOX:
-				/* Treating listbox and combobox identically for now,
-				 * and the behaviour is most appropriate for a combobox */
 				pdf_update_combobox_appearance(ctx, doc, obj);
 				break;
 			}
diff --git a/source/pdf/pdf-form.c b/source/pdf/pdf-form.c
index dcb08bc7..ce51ae4f 100644
--- a/source/pdf/pdf-form.c
+++ b/source/pdf/pdf-form.c
@@ -1276,26 +1276,35 @@ int pdf_text_widget_set_text(fz_context *ctx, pdf_document *doc, pdf_widget *tw,
 	return accepted;
 }
 
-int pdf_choice_widget_options(fz_context *ctx, pdf_document *doc, pdf_widget *tw, char *opts[])
+/* Get either the listed value or the export value. */
+int pdf_choice_widget_options(fz_context *ctx, pdf_document *doc, pdf_widget *tw, int exportval, char *opts[])
 {
 	pdf_annot *annot = (pdf_annot *)tw;
 	pdf_obj *optarr;
-	int i, n;
+	int i, n, m;
 
 	if (!annot)
 		return 0;
 
 	optarr = pdf_dict_get(ctx, annot->obj, PDF_NAME_Opt);
 	n = pdf_array_len(ctx, optarr);
-
+	
 	if (opts)
 	{
 		for (i = 0; i < n; i++)
 		{
-			opts[i] = pdf_to_str_buf(ctx, pdf_array_get(ctx, optarr, i));
+			m = pdf_array_len(ctx, pdf_array_get(ctx, optarr, i));
+			/* If it is a two element array, the second item is the one that we want
+			   if we want the listing value */
+			if (m == 2)
+				if (exportval)
+					opts[i] = pdf_to_str_buf(ctx, pdf_array_get(ctx, pdf_array_get(ctx, optarr, i), 0));
+				else
+					opts[i] = pdf_to_str_buf(ctx, pdf_array_get(ctx, pdf_array_get(ctx, optarr, i), 1));
+			else
+				opts[i] = pdf_to_str_buf(ctx, pdf_array_get(ctx, optarr, i));
 		}
 	}
-
 	return n;
 }