Patch: Multipart/inline support, take 2

[Toralf Lund <toralf kscanners com>]

Attached to this message is my second attempt at introducing proper
multipart support in the message view. I mean "proper" in the sense that
inline parts (Content-disposition: inline) - notably, forwarded messages -
are displayed along with the main body.

In this version, part icons will be included for a subset of multipart/*.
All special handling is related to these; when the icon for a component of
"multipart" type is selected, one or more of the related parts will be
displayed. For simple parts and their icons, the behaviour should be the
same as earlier.

I've tested the updated Balsa on a number of complex messages, and I rather
like the way it looks. The only drawback as far as I can see, is that the
part list is starting to get rather messy. Hopefully, it won't be needed
that often, though.


-- 
Toralf Lund <toralf@kscanners.com>  +47 66 85 51 22
Kongsberg Scanners AS               +47 66 85 51 00 (switchboard)
http://www.kscanners.no/~toralf     +47 66 85 51 01 (fax)
Index: src/balsa-message.c
===================================================================
RCS file: /cvs/gnome/balsa/src/balsa-message.c,v
retrieving revision 1.177
diff -u -b -r1.177 balsa-message.c
--- src/balsa-message.c	2001/08/29 11:56:38	1.177
+++ src/balsa-message.c	2001/09/04 08:56:54
@@ -33,6 +33,9 @@
 #include "mime.h"
 #include "misc.h"
 
+#include <libmutt/mutt.h>
+#include <libmutt/mime.h>
+
 #ifdef USE_PIXBUF
 #include <gdk-pixbuf/gdk-pixbuf.h>
 #endif
@@ -108,6 +111,8 @@
 
 static void select_icon_cb(GnomeIconList * ilist, gint num,
 			   GdkEventButton * event, BalsaMessage * bm);
+static BalsaPartInfo *add_part(BalsaMessage *bm, gint part);
+static void add_multipart(BalsaMessage *bm, LibBalsaMessageBody *parent);
 static void select_part(BalsaMessage * bm, gint part);
 static void part_context_menu_save(GtkWidget * menu_item,
 				   BalsaPartInfo * info);
@@ -156,6 +161,7 @@
 #endif
 static GtkWidget* part_info_mime_button (BalsaPartInfo* info, const gchar* content_type, const gchar* key);
 static void part_context_menu_cb(GtkWidget * menu_item, BalsaPartInfo * info);
+static void part_context_menu_vfs_cb(GtkWidget * menu_item, BalsaPartInfo * info);
 static void part_create_menu (BalsaPartInfo* info);
 
 static GtkViewportClass *parent_class = NULL;
@@ -232,6 +238,13 @@
     gtk_container_add(GTK_CONTAINER(bm), bm->table);
     gtk_widget_show(bm->table);
 
+    bm->content = gtk_vbox_new(FALSE, 0);
+
+    gtk_table_attach(GTK_TABLE(bm->table), bm->content, 0, 1, 1,
+		     2, GTK_EXPAND | GTK_FILL,
+		     GTK_EXPAND | GTK_FILL, 0, 1);
+    gtk_widget_show(bm->content);
+
     bm->header_text = gtk_text_new(NULL, NULL);
     gtk_signal_connect(GTK_OBJECT(bm->header_text), "key_press_event",
 		       (GtkSignalFunc) balsa_message_key_press_event,
@@ -246,7 +259,7 @@
     bm->part_list = gnome_icon_list_new(100, NULL, FALSE);
 
     gnome_icon_list_set_selection_mode(GNOME_ICON_LIST(bm->part_list),
-				       GTK_SELECTION_SINGLE);
+				       GTK_SELECTION_MULTIPLE);
     gtk_signal_connect(GTK_OBJECT(bm->part_list), "select_icon",
 		       GTK_SIGNAL_FUNC(select_icon_cb), bm);
     gtk_signal_connect(GTK_OBJECT(bm->part_list), "size_request",
@@ -1768,7 +1781,6 @@
 	fprintf(stderr, "part end: multipart\n");
 	break;
     case LIBBALSA_MESSAGE_BODY_TYPE_MULTIPART:
-	g_print("Got a TYPEMULTIPART in part2canvas!\n");
 	break;
     case LIBBALSA_MESSAGE_BODY_TYPE_TEXT:
 	if (balsa_app.debug)
@@ -1799,25 +1811,21 @@
 {
     BalsaPartInfo *info = NULL;
     gchar *pix = NULL;
-    gchar *content_type = NULL;
+    gchar *content_type = libbalsa_message_body_get_content_type(body);
     gchar *icon_title = NULL;
     gint pos;
-
+    gboolean is_multipart=libbalsa_message_body_is_multipart(body);
 
-    if (libbalsa_message_body_is_multipart(body)) {
-	if (balsa_app.debug)
-	    fprintf(stderr, "part: multipart\n");
-	display_multipart(bm, body);
-	if (balsa_app.debug)
-	    fprintf(stderr, "part end: multipart\n");
-	return;			/* we don't want a multipart icon */
-    }
-
+    if(!is_multipart ||
+       g_strcasecmp(content_type, "multipart/mixed")==0 ||
+       g_strcasecmp(content_type, "multipart/alternative")==0) {
     bm->part_count++;
     info = part_info_new(body, bm->message);
-    content_type = libbalsa_message_body_get_content_type(body);
 
-    if (body->filename)
+	if (is_multipart) {
+	    icon_title = g_strdup_printf("%s parts", strchr(content_type, '/')+1);
+	    *icon_title = toupper (*icon_title);
+	} else if (body->filename)
 	icon_title =
 	    g_strdup_printf("%s (%s)", body->filename, content_type);
     else
@@ -1832,9 +1840,17 @@
     gnome_icon_list_set_icon_data_full(GNOME_ICON_LIST(bm->part_list), pos,
 				       info, (GtkDestroyNotify)part_info_free);
 
-    g_free(content_type);
     g_free(icon_title);
     g_free(pix);
+    }
+    if (is_multipart) {
+	if (balsa_app.debug)
+	    fprintf(stderr, "part: multipart\n");
+	display_multipart(bm, body);
+	if (balsa_app.debug)
+	    fprintf(stderr, "part end: multipart\n");
+    }
+    g_free(content_type);
 }
 
 static void
@@ -1869,7 +1885,11 @@
         key = list->data;
 
         if (key && g_strcasecmp (key, "icon-filename") 
-	    && g_strncasecmp (key, "fm-", 3)) {
+	    && g_strncasecmp (key, "fm-", 3)
+	    /* Get rid of additional GnomeVFS entries: */
+	    && (!strstr(key, "_") || strstr(key, "."))
+	    && g_strncasecmp(key, "description", 11)) {
+	    
             if ((cmd = gnome_mime_get_value (content_type, key)) != NULL) {
                 if (g_strcasecmp (key, "open") == 0 || 
                     g_strcasecmp (key, "view") == 0 || 
@@ -2039,59 +2059,169 @@
     select_part(bmessage, index);
 }
 
-/* 
- * If part == -1 then change to no part
- * must release selection before hiding a text widget.
- */
-static void
-select_part(BalsaMessage * bm, gint part)
+LibBalsaMessageBody *preferred_part(LibBalsaMessageBody *parts)
 {
-    BalsaPartInfo *info;
+    /* TODO: Consult preferences and/or previous selections */
 
-    if (bm->current_part && bm->current_part->widget) {
-	if(GTK_IS_EDITABLE(bm->current_part->widget) && 
-	   GTK_WIDGET_REALIZED(bm->current_part->widget))
-	    gtk_editable_claim_selection(
-		GTK_EDITABLE(bm->current_part->widget), FALSE, 
-		GDK_CURRENT_TIME);
-	gtk_widget_hide(bm->current_part->widget);
-	gtk_container_remove(GTK_CONTAINER(bm->table),
-			     bm->current_part->widget);
+    LibBalsaMessageBody *body;
+    gchar *content_type;
+
+#ifdef HAVE_GTKHTML
+    for(body=parts; body; body=body->next) {
+	content_type = libbalsa_message_body_get_content_type(body);
+
+	if(g_strcasecmp(content_type, "text/html")==0) {
+	    g_free(content_type);
+	    return body;
+	}
+	g_free(content_type);
     }
+#endif /* HAVE_GTKHTML */
 
+    for(body=parts; body; body=body->next) {
+	content_type = libbalsa_message_body_get_content_type(body);
+
+	if(g_strcasecmp(content_type, "text/plain")==0) {
+	    g_free(content_type);
+	    return body;
+	}
+	g_free(content_type);
+    }
+
+
+    return parts;
+}
+
+
+
+static gint part_icon_no(BalsaMessage *bm, const LibBalsaMessageBody *body)
+{
+    const BalsaPartInfo *info;
+    int part;
+
+    for(part=0; part<bm->part_count; part++) {
+	info = (const BalsaPartInfo *) gnome_icon_list_get_icon_data
+	    (GNOME_ICON_LIST(bm->part_list), part);
+	if(info->body==body)
+	    return part;
+    }
+    return -1;
+}
+
+
+static void add_body(BalsaMessage *bm, 
+		     LibBalsaMessageBody *body)
+{
+    if(body) {
+	gint part=part_icon_no(bm, body);
+	
+	if(part>=0)
+	    add_part(bm, part);
+	else
+	    add_multipart(bm, body);
+    }
+}
+
+
+static void add_multipart(BalsaMessage *bm, LibBalsaMessageBody *parent)
+/* Remarks: *** The tests/assumptions made are NOT verified with the RFCs */
+{
+    if(parent->parts) {
+	gchar *content_type = 
+	    libbalsa_message_body_get_content_type(parent);
+	if(g_strcasecmp(content_type, "multipart/related")==0) {
+	    /* Add the first part */
+	    add_body(bm, parent->parts);
+	} else if(g_strcasecmp(content_type, "multipart/alternative")==0) {
+	    /* Add the most suitable part. */
+	    add_body(bm, preferred_part(parent->parts));
+	} else {
+	    /* Add first (main) part + anything else with 
+	       Content-Disposition: inline */
+	    LibBalsaMessageBody *body=parent->parts;
+	    
+	    if(body) {
+		add_body(bm, body);
+		for(body=body->next; body; body=body->next) {
+		    if(body->mutt_body && 
+		       body->mutt_body->disposition==DISPINLINE)
+			add_body(bm, body);
+		}
+	    }
+	}
+	g_free(content_type);
+    }
+}
+
+
+
+static BalsaPartInfo *add_part(BalsaMessage *bm, gint part)
+{
+    BalsaPartInfo *info=NULL;
+
     if (part != -1) {
+	LibBalsaMessageBodyType type;
+	
 	info = (BalsaPartInfo *) gnome_icon_list_get_icon_data
 	    (GNOME_ICON_LIST(bm->part_list), part);
 
 	g_assert(info != NULL);
 
+	gnome_icon_list_select_icon(GNOME_ICON_LIST(bm->part_list), part);
+
 	if (info->widget == NULL)
 	    part_info_init(bm, info);
 
 	if (info->widget) {
+	    gtk_container_add(GTK_CONTAINER(bm->content), info->widget);
 	    gtk_widget_show(info->widget);
-	    gtk_table_attach(GTK_TABLE(bm->table), info->widget, 0, 1, 1,
-			     2, GTK_EXPAND | GTK_FILL,
-			     GTK_EXPAND | GTK_FILL, 0, 1);
-	} else {
-	    /* HACK! This is a spacer, so that the attachment icons
-	     * will stay at the bottom of the window.
-	     */
-	    GtkWidget *box;
+	}
+	add_multipart(bm, info->body);
+    }
+    
+    return info;
+}
+
+static void hide_all_parts(BalsaMessage *bm)
+{
+    if(bm->current_part) {
+	gint part;
 
-	    box = gtk_hbox_new(FALSE, FALSE);
-	    gtk_widget_show(box);
-	    gtk_table_attach(GTK_TABLE(bm->table), box, 0, 1, 1, 2,
-			     GTK_EXPAND | GTK_FILL, GTK_EXPAND | GTK_FILL,
-			     0, 0);
+	for(part=0; part<bm->part_count; part++) {
+	    BalsaPartInfo *current_part=(BalsaPartInfo *) gnome_icon_list_get_icon_data
+		(GNOME_ICON_LIST(bm->part_list), part);
+	    
+	    if(current_part && current_part->widget && 
+	       GTK_WIDGET_VISIBLE(current_part->widget)) {
+		if(GTK_IS_EDITABLE(current_part->widget) && 
+		   GTK_WIDGET_REALIZED(current_part->widget))
+		    gtk_editable_claim_selection(
+						 GTK_EDITABLE(current_part->widget), FALSE, 
+						 GDK_CURRENT_TIME);
+		gtk_widget_hide(current_part->widget);
+		gtk_container_remove(GTK_CONTAINER(bm->content),
+				     current_part->widget);
 	}
-	bm->current_part = info;
-	gtk_signal_emit(GTK_OBJECT(bm),
-			balsa_message_signals[SELECT_PART]);
-    } else {
-	bm->current_part = NULL;
+	    gnome_icon_list_unselect_icon(GNOME_ICON_LIST(bm->part_list), part);
     }
+    }
+}
+
+
+/* 
+ * If part == -1 then change to no part
+ * must release selection before hiding a text widget.
+ */
+static void
+select_part(BalsaMessage * bm, gint part)
+{
+    hide_all_parts(bm);
 
+    bm->current_part = add_part(bm, part);
+
+    if(bm->current_part)
+	gtk_signal_emit(GTK_OBJECT(bm),
+			balsa_message_signals[SELECT_PART]);
 
     scroll_set(GTK_VIEWPORT(bm)->hadjustment, 0);
     scroll_set(GTK_VIEWPORT(bm)->vadjustment, 0);