[geary] Rework ComposerWidget's pending attachment implementation. Bug 712995.

[Michael Gratton <mjog src gnome org>]

commit efb7ecbe8157227e1561ed1f5a910d87930e2996
Author: Michael James Gratton <mike vee net>
Date:   Sun Oct 2 11:05:27 2016 +1100

    Rework ComposerWidget's pending attachment implementation. Bug 712995.
    
    This merges the pending attachment add & check methods to do both at
    once, so the logic for determining if a panding attachment should be
    added doesn't need to be duplicated.
    
    Also changes the behaviour of pending attachments to always include
    inline attachments, even when only replying, since they should be
    displayed if included in the quote.
    
    * src/client/composer/composer-widget.vala (ComposerWidget): Add state
      flag to specify which pending attachments should be included. Move all
      private attachment-related fields to the same place in the
      source. Combine ::add_pending_attachments and
      ::check_pending_attachments into new ::update_pending_attachments
      method, update call sites.

 src/client/composer/composer-widget.vala |   85 +++++++++++++++++++-----------
 1 files changed, 54 insertions(+), 31 deletions(-)
---
diff --git a/src/client/composer/composer-widget.vala b/src/client/composer/composer-widget.vala
index 82f6dd6..9a5c336 100644
--- a/src/client/composer/composer-widget.vala
+++ b/src/client/composer/composer-widget.vala
@@ -33,6 +33,8 @@ public class ComposerWidget : Gtk.EventBox {
         INLINE_COMPACT
     }
 
+    private enum AttachPending { ALL, INLINE_ONLY }
+
     private class FromAddressMap {
         public Geary.Account account;
         public Geary.RFC822.MailboxAddresses from;
@@ -276,11 +278,6 @@ public class ComposerWidget : Gtk.EventBox {
 
     private string? body_html = null;
 
-    private Gee.Set<File> attached_files = new Gee.HashSet<File>(Geary.Files.nullable_hash,
-        Geary.Files.nullable_equal);
-    private Gee.Set<File> inline_files = new Gee.HashSet<File>(Geary.Files.nullable_hash,
-        Geary.Files.nullable_equal);
-
     [GtkChild]
     private Gtk.Box composer_container;
     [GtkChild]
@@ -352,7 +349,6 @@ public class ComposerWidget : Gtk.EventBox {
     private SpellCheckPopover? spell_check_popover = null;
     private string? hover_url = null;
     private bool is_attachment_overlay_visible = false;
-    private Gee.List<Geary.Attachment>? pending_attachments = null;
     private Geary.RFC822.MailboxAddresses reply_to_addresses;
     private Geary.RFC822.MailboxAddresses reply_cc_addresses;
     private string reply_subject = "";
@@ -360,6 +356,12 @@ public class ComposerWidget : Gtk.EventBox {
     private bool top_posting = true;
     private string? last_quote = null;
 
+    private Gee.List<Geary.Attachment>? pending_attachments = null;
+    private AttachPending pending_include = AttachPending.INLINE_ONLY;
+    private Gee.Set<File> attached_files = new Gee.HashSet<File>(Geary.Files.nullable_hash,
+        Geary.Files.nullable_equal);
+    private Gee.Set<File> inline_files = new Gee.HashSet<File>(Geary.Files.nullable_hash,
+        Geary.Files.nullable_equal);
     private Geary.App.DraftManager? draft_manager = null;
     private Geary.EmailFlags draft_flags = new Geary.EmailFlags.with(Geary.EmailFlags.DRAFT);
     private uint draft_save_timeout_id = 0;
@@ -467,10 +469,18 @@ public class ComposerWidget : Gtk.EventBox {
 
         this.from = new Geary.RFC822.MailboxAddresses.single(account.information.primary_mailbox);
 
-        if (referred != null)
+        if (referred != null) {
             fill_in_from_referred(referred, quote);
 
+            if (is_referred_draft ||
+                compose_type == ComposeType.NEW_MESSAGE ||
+                compose_type == ComposeType.FORWARD) {
+                this.pending_include = AttachPending.ALL;
+            }
+        }
+
         update_from_field();
+        update_pending_attachments(this.pending_include, true);
 
         // only add signature if the option is actually set and if this is not a draft
         if (this.account.information.use_email_signature && !is_referred_draft)
@@ -780,7 +790,6 @@ public class ComposerWidget : Gtk.EventBox {
                 } catch (Error error) {
                     debug("Error getting message body: %s", error.message);
                 }
-                add_pending_attachments();
             break;
 
             case ComposeType.REPLY:
@@ -799,7 +808,6 @@ public class ComposerWidget : Gtk.EventBox {
                 this.subject = forward_subject;
                 this.body_html = "\n\n" + Geary.RFC822.Utils.quote_email_for_forward(referred, quote,
                     Geary.RFC822.TextFormat.HTML);
-                add_pending_attachments();
             break;
         }
     }
@@ -1526,30 +1534,45 @@ public class ComposerWidget : Gtk.EventBox {
         this.container.close_container();
     }
 
-    private void add_pending_attachments() {
-        foreach(Geary.Attachment att in this.pending_attachments) {
-            try {
-                add_attachment(
-                    att.file,
-                    att.content_disposition.disposition_type
-                );
-            } catch (Error err) {
-                attachment_failed(err.message);
-            }
-        }
-    }
-
-    private void check_pending_attachments() {
+    // Both adds pending attachments and updates the UI if there are
+    // any that were left out, that could have been added manually.
+    private void update_pending_attachments(AttachPending include, bool do_add) {
+        bool manual_enabled = false;
         if (this.pending_attachments != null) {
-            foreach (Geary.Attachment attachment in this.pending_attachments) {
-                if (!this.attached_files.contains(attachment.file) &&
-                    !this.inline_files.contains(attachment.file)) {
-                    this.header.show_pending_attachments = true;
-                    return;
+            foreach(Geary.Attachment part in this.pending_attachments) {
+                try {
+                    Geary.Mime.DispositionType? type =
+                    part.content_disposition.disposition_type;
+                    File file = part.file;
+                    if (type == Geary.Mime.DispositionType.INLINE) {
+                        // Inline part with no CID, so it is not
+                        // possible to be referenced from an IMG SRC
+                        // using a cid: URL, hence treat it as an
+                        // attachment instead.
+                        type = Geary.Mime.DispositionType.ATTACHMENT;
+                    }
+
+                    if (type == Geary.Mime.DispositionType.INLINE ||
+                        include == AttachPending.ALL) {
+                        // The pending attachment should be added
+                        // automatically, so add it if asked to and it
+                        // hasn't already been added
+                        if (do_add &&
+                            !(file in this.attached_files) &&
+                            !(file in this.inline_files)) {
+                            add_attachment(file, type);
+                        }
+                    } else {
+                        // The pending attachment should only be added
+                        // manually
+                        manual_enabled = true;
+                    }
+                } catch (Error err) {
+                    attachment_failed(err.message);
                 }
             }
         }
-        this.header.show_pending_attachments = false;
+        this.header.show_pending_attachments = manual_enabled;
     }
 
     private void add_attachment(File target,
@@ -1644,7 +1667,7 @@ public class ComposerWidget : Gtk.EventBox {
         else
             attachments_box.hide();
 
-        check_pending_attachments();
+        update_pending_attachments(this.pending_include, true);
     }
 
     [GtkCallback]
@@ -2406,7 +2429,7 @@ public class ComposerWidget : Gtk.EventBox {
     }
 
     private void on_pending_attachments() {
-        add_pending_attachments();
+        update_pending_attachments(AttachPending.ALL, true);
     }
 
     private void on_insert_image(SimpleAction action, Variant? param) {