Add support for annotation creation

6 files changed, 152 insertions, 6 deletions

diff --git a/pdf/mupdf-internal.h b/pdf/mupdf-internal.h
index 4f2524ad..6ac228ef 100644
--- a/pdf/mupdf-internal.h
+++ b/pdf/mupdf-internal.h
@@ -494,6 +494,7 @@ float pdf_text_stride(fz_context *ctx, pdf_font_desc *fontdesc, float fontsize,
 
 struct pdf_annot_s
 {
+	pdf_page *page;
 	pdf_obj *obj;
 	fz_rect rect;
 	fz_rect pagerect;
@@ -513,7 +514,7 @@ pdf_obj *pdf_load_name_tree(pdf_document *doc, char *which);
 
 fz_link *pdf_load_link_annots(pdf_document *, pdf_obj *annots, fz_matrix page_ctm);
 
-pdf_annot *pdf_load_annots(pdf_document *, pdf_obj *annots, fz_matrix page_ctm);
+pdf_annot *pdf_load_annots(pdf_document *, pdf_obj *annots, pdf_page *page);
 void pdf_update_annot(pdf_document *, pdf_annot *annot);
 void pdf_free_annot(fz_context *ctx, pdf_annot *link);
 
@@ -583,6 +584,8 @@ int pdf_choice_widget_options(pdf_document *doc, fz_widget *tw, char *opts[]);
 int pdf_choice_widget_is_multiselect(pdf_document *doc, fz_widget *tw);
 int pdf_choice_widget_value(pdf_document *doc, fz_widget *tw, char *opts[]);
 void pdf_choice_widget_set_value(pdf_document *doc, fz_widget *tw, int n, char *opts[]);
+pdf_annot *pdf_create_annot(pdf_document *doc, pdf_page *page, fz_annot_type type);
+void pdf_set_annot_appearance(pdf_document *doc, pdf_annot *annot, fz_display_list *disp_list);
 void pdf_set_doc_event_callback(pdf_document *doc, fz_doc_event_cb *event_cb, void *data);
 
 void pdf_event_issue_alert(pdf_document *doc, fz_alert_event *event);
diff --git a/pdf/mupdf.h b/pdf/mupdf.h
index e10a4982..27bd1644 100644
--- a/pdf/mupdf.h
+++ b/pdf/mupdf.h
@@ -78,6 +78,7 @@ void pdf_dict_put(pdf_obj *dict, pdf_obj *key, pdf_obj *val);
 void pdf_dict_puts(pdf_obj *dict, const char *key, pdf_obj *val);
 void pdf_dict_puts_drop(pdf_obj *dict, const char *key, pdf_obj *val);
 void pdf_dict_putp(pdf_obj *dict, const char *key, pdf_obj *val);
+void pdf_dict_putp_drop(pdf_obj *dict, const char *key, pdf_obj *val);
 void pdf_dict_del(pdf_obj *dict, pdf_obj *key);
 void pdf_dict_dels(pdf_obj *dict, const char *key);
 void pdf_sort_dict(pdf_obj *dict);
diff --git a/pdf/pdf_annot.c b/pdf/pdf_annot.c
index 4d0d0f84..b93fa258 100644
--- a/pdf/pdf_annot.c
+++ b/pdf/pdf_annot.c
@@ -353,7 +353,7 @@ pdf_transform_annot(pdf_annot *annot)
 }
 
 pdf_annot *
-pdf_load_annots(pdf_document *xref, pdf_obj *annots, fz_matrix page_ctm)
+pdf_load_annots(pdf_document *xref, pdf_obj *annots, pdf_page *page)
 {
 	pdf_annot *annot, *head, *tail;
 	pdf_obj *obj, *ap, *as, *n, *rect;
@@ -400,9 +400,10 @@ pdf_load_annots(pdf_document *xref, pdf_obj *annots, fz_matrix page_ctm)
 				n = pdf_dict_get(n, as);
 
 			annot = fz_malloc_struct(ctx, pdf_annot);
+			annot->page = page;
 			annot->obj = pdf_keep_obj(obj);
 			annot->rect = pdf_to_rect(ctx, rect);
-			annot->pagerect = fz_transform_rect(page_ctm, annot->rect);
+			annot->pagerect = fz_transform_rect(page->ctm, annot->rect);
 			annot->ap = NULL;
 			annot->type = pdf_field_type(xref, obj);
 
@@ -507,3 +508,127 @@ pdf_bound_annot(pdf_document *doc, pdf_annot *annot)
 		return annot->pagerect;
 	return fz_empty_rect;
 }
+
+pdf_annot *
+pdf_create_annot(pdf_document *doc, pdf_page *page, fz_annot_type type)
+{
+	fz_context *ctx = doc->ctx;
+	pdf_annot *annot = NULL;
+	pdf_obj *annot_obj = pdf_new_dict(ctx, 0);
+
+	fz_var(annot);
+	fz_try(ctx)
+	{
+		fz_rect rect = {0.0, 0.0, 0.0, 0.0};
+		char *type_str = "";
+		pdf_obj *annot_arr = pdf_dict_gets(page->me, "Annots");
+		if (annot_arr == NULL)
+		{
+			annot_arr = pdf_new_array(ctx, 0);
+			pdf_dict_puts_drop(page->me, "Annots", annot_arr);
+		}
+
+		pdf_dict_puts_drop(annot_obj, "Type", pdf_new_name(ctx, "Annot"));
+
+		switch(type)
+		{
+		case FZ_ANNOT_STRIKEOUT:
+			type_str = "StrikeOut";
+			break;
+		}
+
+		pdf_dict_puts_drop(annot_obj, "Subtype", pdf_new_name(ctx, type_str));
+		pdf_dict_puts_drop(annot_obj, "Rect", pdf_new_rect(ctx, rect));
+
+		annot = fz_malloc_struct(ctx, pdf_annot);
+		annot->page = page;
+		annot->obj = pdf_keep_obj(annot_obj);
+		annot->rect = rect;
+		annot->pagerect = rect;
+		annot->ap = NULL;
+		annot->type = FZ_WIDGET_TYPE_NOT_WIDGET;
+
+		/*
+			Both annotation object and annotation structure are now created.
+			Insert the object in the hierarchy and the structure in the
+			page's array.
+		*/
+		pdf_array_push(annot_arr, annot_obj);
+
+		/*
+			Linking must be done before any call that might throw because
+			pdf_free_annot below actually frees a list
+		*/
+		annot->next = page->annots;
+		page->annots = annot;
+
+		doc->dirty = 1;
+	}
+	fz_always(ctx)
+	{
+		pdf_drop_obj(annot_obj);
+	}
+	fz_catch(ctx)
+	{
+		pdf_free_annot(ctx, annot);
+		fz_rethrow(ctx);
+	}
+
+	return annot;
+}
+
+void
+pdf_set_annot_appearance(pdf_document *doc, pdf_annot *annot, fz_display_list *disp_list)
+{
+	fz_context *ctx = doc->ctx;
+	fz_matrix ctm = fz_invert_matrix(annot->page->ctm);
+	fz_rect rect;
+	fz_matrix mat = fz_identity;
+	fz_device *dev = fz_new_bbox_device(ctx, &rect);
+
+	fz_try(ctx)
+	{
+		pdf_obj *ap_obj;
+
+		fz_run_display_list(disp_list, dev, ctm, fz_infinite_rect, NULL);
+		fz_free_device(dev);
+		dev = NULL;
+
+		pdf_dict_puts_drop(annot->obj, "Rect", pdf_new_rect(ctx, rect));
+
+		/* See if there is a current normal appearance */
+		ap_obj = pdf_dict_getp(annot->obj, "AP/N");
+		if (!pdf_is_stream(doc, pdf_to_num(annot->obj), pdf_to_gen(annot->obj)))
+			ap_obj = NULL;
+
+		if (ap_obj == NULL)
+		{
+			ap_obj = pdf_new_xobject(doc, rect, mat);
+			pdf_dict_putp_drop(annot->obj, "AP/N", ap_obj);
+		}
+		else
+		{
+			pdf_dict_puts_drop(ap_obj, "Rect", pdf_new_rect(ctx, rect));
+			pdf_dict_puts_drop(ap_obj, "Matrix", pdf_new_matrix(ctx, mat));
+		}
+
+		/* Remove annot reference to the xobject and don't recreate it
+		so that pdf_update_page counts it as dirty */
+		pdf_drop_xobject(ctx, annot->ap);
+		annot->ap = NULL;
+
+		annot->rect = rect;
+		annot->pagerect = fz_transform_rect(annot->page->ctm, rect);
+
+		dev = pdf_new_pdf_device(doc, ap_obj, pdf_dict_gets(ap_obj, "Resources"), mat);
+		fz_run_display_list(disp_list, dev, ctm, fz_infinite_rect, NULL);
+		fz_free_device(dev);
+
+		doc->dirty = 1;
+	}
+	fz_catch(ctx)
+	{
+		fz_free_device(dev);
+		fz_rethrow(ctx);
+	}
+}
diff --git a/pdf/pdf_form.c b/pdf/pdf_form.c
index 8fbebbc8..e92ba738 100644
--- a/pdf/pdf_form.c
+++ b/pdf/pdf_form.c
@@ -3,8 +3,6 @@
 
 #define MATRIX_COEFS (6)
 
-#define FZ_WIDGET_TYPE_NOT_WIDGET (-1)
-
 enum
 {
 	Ff_Multiline = 1 << (13-1),
diff --git a/pdf/pdf_object.c b/pdf/pdf_object.c
index 9ebb4aec..8a2d71fc 100644
--- a/pdf/pdf_object.c
+++ b/pdf/pdf_object.c
@@ -1056,6 +1056,25 @@ pdf_dict_putp(pdf_obj *obj, const char *keys, pdf_obj *val)
 }
 
 void
+pdf_dict_putp_drop(pdf_obj *obj, const char *keys, pdf_obj *val)
+{
+	fz_context *ctx = obj->ctx;
+
+	fz_try(ctx)
+	{
+		pdf_dict_putp(obj, keys, val);
+	}
+	fz_always(ctx)
+	{
+		pdf_drop_obj(val);
+	}
+	fz_catch(ctx)
+	{
+		fz_rethrow(ctx);
+	}
+}
+
+void
 pdf_dict_dels(pdf_obj *obj, const char *key)
 {
 	RESOLVE(obj);
diff --git a/pdf/pdf_page.c b/pdf/pdf_page.c
index 93643e7c..a071732a 100644
--- a/pdf/pdf_page.c
+++ b/pdf/pdf_page.c
@@ -408,7 +408,7 @@ pdf_load_page(pdf_document *xref, int number)
 	if (obj)
 	{
 		page->links = pdf_load_link_annots(xref, obj, page->ctm);
-		page->annots = pdf_load_annots(xref, obj, page->ctm);
+		page->annots = pdf_load_annots(xref, obj, page);
 	}
 
 	page->duration = pdf_to_real(pdf_dict_gets(pageobj, "Dur"));