Forms: initial simple handling of check boxes and radio buttons

1 files changed, 103 insertions, 10 deletions

diff --git a/pdf/pdf_form.c b/pdf/pdf_form.c
index ff5babeb..7594ed08 100644
--- a/pdf/pdf_form.c
+++ b/pdf/pdf_form.c
@@ -1,27 +1,104 @@
 #include "fitz-internal.h"
 #include "mupdf-internal.h"
 
+enum
+{
+	Ff_NoToggleToOff = 1 << (15-1),
+	Ff_Radio         = 1 << (16-1),
+	Ff_Pushbutton    = 1 << (17-1),
+	Ff_RadioInUnison = 1 << (26-1)
+};
+
+static char *get_annot_type(pdf_obj *obj)
+{
+	pdf_obj *type = NULL;
+
+	while (!type && obj)
+	{
+		type = pdf_dict_gets(obj, "FT");
+
+		if (!type)
+			obj = pdf_dict_gets(obj, "Parent");
+	}
+
+	return type ? pdf_to_name(type)
+				: NULL;
+}
+
+static int get_annot_field_flags(pdf_obj *obj)
+{
+	pdf_obj *flags = NULL;
+
+	while (!flags && obj)
+	{
+		flags = pdf_dict_gets(obj, "Ff");
+
+		if (!flags)
+			obj = pdf_dict_gets(obj, "Parent");
+	}
+
+	return flags ? pdf_to_int(flags)
+				 : 0;
+}
+
+static void toggle_check_box(pdf_document *doc, pdf_obj *obj)
+{
+	pdf_obj *as;
+
+	as = pdf_dict_gets(obj, "AS");
+
+	if (strcmp(pdf_to_name(as), "Off"))
+	{
+		/* "as" neither missing nor set to Off. Set it to Off. */
+		pdf_obj *off = fz_new_name(doc->ctx, "Off");
+		pdf_dict_puts(obj, "AS", off);
+		pdf_drop_obj(off);
+	}
+	else
+	{
+	    pdf_obj *ap, *n, *key;
+		int len, i;
+
+		ap = pdf_dict_gets(obj, "AP");
+		n = pdf_dict_gets(ap, "N");
+
+		/* Look for a key that isn't "Off" */
+		len = pdf_dict_len(n);
+		for (i = 0; i < len; i++)
+		{
+			key = pdf_dict_get_key(n, i);
+			if (pdf_is_name(key) && strcmp(pdf_to_name(key), "Off"))
+			{
+				pdf_dict_puts(obj, "AS", key);
+				break;
+			}
+		}
+	}
+
+	/* FIXME: should probably update the V entry in the field dictionary too */
+}
+
 int pdf_pass_event(pdf_document *doc, pdf_page *page, fz_ui_event *ui_event)
 {
+	pdf_annot *annot;
+	pdf_hotspot *hp = &doc->hotspot;
+	fz_point  *pt = &(ui_event->event.pointer.pt);
 	int changed = 0;
 
+	for (annot = page->annots; annot; annot = annot->next)
+	{
+		if (pt->x >= annot->pagerect.x0 && pt->x <= annot->pagerect.x1)
+			if (pt->y >= annot->pagerect.y0 && pt->y <= annot->pagerect.y1)
+				break;
+	}
+
 	switch (ui_event->etype)
 	{
 	case FZ_EVENT_TYPE_POINTER:
 		{
-			pdf_hotspot *hp = &doc->hotspot;
-			fz_point  *pt = &(ui_event->event.pointer.pt);
-			pdf_annot *annot;
 			switch (ui_event->event.pointer.ptype)
 			{
 			case FZ_POINTER_DOWN:
-				for (annot = page->annots; annot; annot = annot->next)
-				{
-					if (pt->x >= annot->pagerect.x0 && pt->x <= annot->pagerect.x1)
-						if (pt->y >= annot->pagerect.y0 && pt->y <= annot->pagerect.y1)
-							break;
-				}
-
 				if (annot)
 				{
 					hp->num = pdf_to_num(annot->obj);
@@ -38,6 +115,22 @@ int pdf_pass_event(pdf_document *doc, pdf_page *page, fz_ui_event *ui_event)
 				hp->num = 0;
 				hp->gen = 0;
 				hp->state = 0;
+
+				if (annot)
+				{
+					char *atype = get_annot_type(annot->obj);
+					int   flags = get_annot_field_flags(annot->obj);
+
+					if (!strcmp(atype, "Btn"))
+					{
+						if ((flags & (Ff_Pushbutton | Ff_Radio)) == 0)
+							toggle_check_box(doc, annot->obj);
+
+						/* FIXME: treating radio buttons like check boxes, for now */
+						if ((flags & (Ff_Pushbutton | Ff_Radio)) == Ff_Radio)
+							toggle_check_box(doc, annot->obj);
+					}
+				}
 				break;
 			}