[geary/wip/738188-multireplies: 4/5] Allow quotes from multiple messages in a single reply

[Robert Schroll <rschroll src gnome org>]

commit 2d1d2ed31c293f56f586c3b70525761aa3388e32
Author: Robert Schroll <rschroll gmail com>
Date:   Tue Jan 13 13:52:35 2015 -0800

    Allow quotes from multiple messages in a single reply
    
    When replying to a message, we use the existing inline composer if it
    already references the message we're replying to, or if we're replying
    with a quote.  Replies without quotes get made into new composers.
    
    When adding a new message as a reply in a composer, we add the relevant
    addresses to the to and cc lines, based on the current reply type.  We
    remove duplicates, and don't include any to addresses as cc.  We also
    keep track of a total to and total cc list, which gets swapped in if a
    reply action is to change the reply type.
    
    We keep track of all the replied-to message ids and include all of them
    in the In-Reply-To header.  However, the References header only includes
    message ids from the first message replied to.  This is because RFC 2822
    requires this header to represent a single lineage, which we cannot
    guarantee if we're replying to different branches of the conversation.

 src/client/application/geary-controller.vala |    3 +-
 src/client/composer/composer-widget.vala     |   59 ++++++++++++++++++--------
 src/engine/rfc822/rfc822-message-data.vala   |    4 +-
 src/engine/rfc822/rfc822-utils.vala          |   29 +++++++++++++
 4 files changed, 74 insertions(+), 21 deletions(-)
---
diff --git a/src/client/application/geary-controller.vala b/src/client/application/geary-controller.vala
index 544c407..7b1ac8b 100644
--- a/src/client/application/geary-controller.vala
+++ b/src/client/application/geary-controller.vala
@@ -2147,7 +2147,8 @@ public class GearyController : Geary.BaseObject {
         if (compose_type != null && compose_type != ComposerWidget.ComposeType.NEW_MESSAGE) {
             foreach (ComposerWidget cw in composer_widgets) {
                 if (cw.state != ComposerWidget.ComposerState.DETACHED &&
-                    referred != null && referred.id.equal_to(cw.referred_id)) {
+                    ((referred != null && cw.referred_ids.contains(referred.id)) ||
+                     quote != null)) {
                     cw.change_compose_type(compose_type, referred, quote);
                     return false;
                 }
diff --git a/src/client/composer/composer-widget.vala b/src/client/composer/composer-widget.vala
index ece7d33..5de16d1 100644
--- a/src/client/composer/composer-widget.vala
+++ b/src/client/composer/composer-widget.vala
@@ -146,7 +146,7 @@ public class ComposerWidget : Gtk.EventBox {
         set { reply_to_entry.set_text(value); }
     }
     
-    public string in_reply_to { get; set; }
+    public Gee.Set<Geary.RFC822.MessageID> in_reply_to = new Gee.HashSet<Geary.RFC822.MessageID>();
     public string references { get; set; }
     
     public string subject {
@@ -176,7 +176,7 @@ public class ComposerWidget : Gtk.EventBox {
     
     public ComposeType compose_type { get; private set; default = ComposeType.NEW_MESSAGE; }
     
-    public Geary.EmailIdentifier? referred_id { get; private set; default = null; }
+    public Gee.Set<Geary.EmailIdentifier> referred_ids = new Gee.HashSet<Geary.EmailIdentifier>();
     
     public bool blank {
         get {
@@ -234,7 +234,6 @@ public class ComposerWidget : Gtk.EventBox {
     private Geary.RFC822.MailboxAddresses reply_cc_addresses;
     private string reply_subject = "";
     private string forward_subject = "";
-    private string reply_message_id = "";
     private bool top_posting = true;
     private string? last_quote = null;
     
@@ -414,13 +413,9 @@ public class ComposerWidget : Gtk.EventBox {
         from_multiple.changed.connect(on_from_changed);
         
         if (referred != null) {
-            this.referred_id = referred.id;
-            string? sender_address = account.information.get_mailbox_address().address;
-            reply_to_addresses = Geary.RFC822.Utils.create_to_addresses_for_reply(referred, sender_address);
-            reply_cc_addresses = Geary.RFC822.Utils.create_cc_addresses_for_reply_all(referred, 
sender_address);
+            add_recipients_and_ids(compose_type, referred);
             reply_subject = Geary.RFC822.Utils.create_subject_for_reply(referred);
             forward_subject = Geary.RFC822.Utils.create_subject_for_forward(referred);
-            reply_message_id = referred.message_id.value;
             last_quote = quote;
             switch (compose_type) {
                 case ComposeType.NEW_MESSAGE:
@@ -431,7 +426,7 @@ public class ComposerWidget : Gtk.EventBox {
                     if (referred.bcc != null)
                         bcc_entry.addresses = referred.bcc;
                     if (referred.in_reply_to != null)
-                        in_reply_to = referred.in_reply_to.to_rfc822_string();
+                        in_reply_to.add_all(referred.in_reply_to.list);
                     if (referred.references != null)
                         references = referred.references.to_rfc822_string();
                     if (referred.subject != null)
@@ -450,12 +445,7 @@ public class ComposerWidget : Gtk.EventBox {
                 
                 case ComposeType.REPLY:
                 case ComposeType.REPLY_ALL:
-                    to_entry.addresses = reply_to_addresses;
-                    if (compose_type == ComposeType.REPLY_ALL)
-                        cc_entry.addresses = reply_cc_addresses;
-                    to_entry.modified = cc_entry.modified = false;
                     subject = reply_subject;
-                    in_reply_to = reply_message_id;
                     references = Geary.RFC822.Utils.reply_references(referred);
                     body_html = "\n\n" + Geary.RFC822.Utils.quote_email_for_reply(referred, quote, true);
                     pending_attachments = referred.attachments;
@@ -766,8 +756,10 @@ public class ComposerWidget : Gtk.EventBox {
         if (reply_to_entry.addresses != null)
             email.reply_to = reply_to_entry.addresses;
         
-        if (!Geary.String.is_empty(in_reply_to))
-            email.in_reply_to = in_reply_to;
+        if ((compose_type == ComposeType.REPLY || compose_type == ComposeType.REPLY_ALL) &&
+            !in_reply_to.is_empty)
+            email.in_reply_to =
+                new Geary.RFC822.MessageIDList.from_collection(in_reply_to).to_rfc822_string();
         
         if (!Geary.String.is_empty(references))
             email.references = references;
@@ -804,6 +796,9 @@ public class ComposerWidget : Gtk.EventBox {
             // Always use reply styling, since forward styling doesn't work for inline quotes
             document.exec_command("insertHTML", false,
                 Geary.RFC822.Utils.quote_email_for_reply(referred, quote, true));
+            
+            if (!referred_ids.contains(referred.id))
+                add_recipients_and_ids(new_type, referred);
         } else if (new_type != compose_type) {
             bool recipients_modified = to_entry.modified || cc_entry.modified || bcc_entry.modified;
             switch (new_type) {
@@ -818,7 +813,6 @@ public class ComposerWidget : Gtk.EventBox {
                     } else {
                         to_entry.select_region(0, -1);
                     }
-                    in_reply_to = reply_message_id;
                 break;
                 
                 case ComposeType.FORWARD:
@@ -831,7 +825,6 @@ public class ComposerWidget : Gtk.EventBox {
                     } else {
                         to_entry.select_region(0, -1);
                     }
-                    in_reply_to = "";
                 break;
                 
                 default:
@@ -844,6 +837,36 @@ public class ComposerWidget : Gtk.EventBox {
         set_focus();
     }
     
+    private void add_recipients_and_ids(ComposeType type, Geary.Email referred) {
+        string? sender_address = account.information.get_mailbox_address().address;
+        Geary.RFC822.MailboxAddresses to_addresses =
+            Geary.RFC822.Utils.create_to_addresses_for_reply(referred, sender_address);
+        Geary.RFC822.MailboxAddresses cc_addresses =
+            Geary.RFC822.Utils.create_cc_addresses_for_reply_all(referred, sender_address);
+        reply_to_addresses = Geary.RFC822.Utils.merge_addresses(reply_to_addresses, to_addresses);
+        reply_cc_addresses = Geary.RFC822.Utils.remove_addresses(
+            Geary.RFC822.Utils.merge_addresses(reply_cc_addresses, cc_addresses),
+            reply_to_addresses);
+        
+        bool recipients_modified = to_entry.modified || cc_entry.modified || bcc_entry.modified;
+        if (!recipients_modified) {
+            if (type == ComposeType.REPLY || type == ComposeType.REPLY_ALL)
+                to_entry.addresses = Geary.RFC822.Utils.merge_addresses(to_entry.addresses,
+                    to_addresses);
+            if (type == ComposeType.REPLY_ALL)
+                cc_entry.addresses = Geary.RFC822.Utils.remove_addresses(
+                    Geary.RFC822.Utils.merge_addresses(cc_entry.addresses, cc_addresses),
+                    to_entry.addresses);
+            else
+                cc_entry.addresses = Geary.RFC822.Utils.remove_addresses(cc_entry.addresses,
+                    to_entry.addresses);
+            to_entry.modified = cc_entry.modified = false;
+        }
+        
+        in_reply_to.add(referred.message_id);
+        referred_ids.add(referred.id);
+    }
+    
     private void add_signature_and_cursor() {
         string? signature = null;
         
diff --git a/src/engine/rfc822/rfc822-message-data.vala b/src/engine/rfc822/rfc822-message-data.vala
index e8ed1e3..440b874 100644
--- a/src/engine/rfc822/rfc822-message-data.vala
+++ b/src/engine/rfc822/rfc822-message-data.vala
@@ -46,10 +46,10 @@ public class Geary.RFC822.MessageIDList : Geary.MessageData.AbstractMessageData,
         list = new Gee.ArrayList<MessageID>();
     }
     
-    public MessageIDList.from_list(Gee.List<MessageID> list) {
+    public MessageIDList.from_collection(Gee.Collection<MessageID> collection) {
         this ();
         
-        foreach(MessageID msg_id in list)
+        foreach(MessageID msg_id in collection)
             this.list.add(msg_id);
     }
     
diff --git a/src/engine/rfc822/rfc822-utils.vala b/src/engine/rfc822/rfc822-utils.vala
index e97e2e3..7837e57 100644
--- a/src/engine/rfc822/rfc822-utils.vala
+++ b/src/engine/rfc822/rfc822-utils.vala
@@ -111,6 +111,35 @@ public Geary.RFC822.MailboxAddresses create_cc_addresses_for_reply_all(Geary.Ema
     return new Geary.RFC822.MailboxAddresses(new_cc);
 }
 
+public Geary.RFC822.MailboxAddresses merge_addresses(Geary.RFC822.MailboxAddresses? first,
+    Geary.RFC822.MailboxAddresses? second) {
+    Gee.List<Geary.RFC822.MailboxAddress> result = new Gee.ArrayList<Geary.RFC822.MailboxAddress>();
+    if (first != null) {
+        result.add_all(first.get_all());
+        // Add addresses from second that aren't in first.
+        if (second != null)
+            foreach (Geary.RFC822.MailboxAddress address in second)
+                if (!first.contains_normalized(address.address))
+                    result.add(address);
+    } else if (second != null) {
+        result.add_all(second.get_all());
+    }
+    
+    return new Geary.RFC822.MailboxAddresses(result);
+}
+
+public Geary.RFC822.MailboxAddresses remove_addresses(Geary.RFC822.MailboxAddresses? from_addresses,
+    Geary.RFC822.MailboxAddresses? remove_addresses) {
+    Gee.List<Geary.RFC822.MailboxAddress> result = new Gee.ArrayList<Geary.RFC822.MailboxAddress>();
+    if (from_addresses != null) {
+        result.add_all(from_addresses.get_all());
+        if (remove_addresses != null)
+            foreach (Geary.RFC822.MailboxAddress address in remove_addresses)
+                remove_address(result, address.address, true);
+    }
+    return new Geary.RFC822.MailboxAddresses(result);
+}
+
 public string reply_references(Geary.Email source) {
     // generate list for References
     Gee.ArrayList<RFC822.MessageID> list = new Gee.ArrayList<RFC822.MessageID>();