[gitg] Show extended git message as part of the scrolled area

[Jesse van den Kieboom <jessevdk src gnome org>]

commit 73d6b6e61b3dae86a666b28d3c9f1d637e1e2ffa
Author: Jesse van den Kieboom <jessevdk gnome org>
Date:   Fri Aug 19 09:01:53 2016 +0200

    Show extended git message as part of the scrolled area
    
    https://bugzilla.gnome.org/show_bug.cgi?id=769239

 libgitg/gitg-diff-view-commit-details.vala         |    6 ++--
 libgitg/gitg-diff-view.vala                        |   33 ++++++++++++++++++++
 .../resources/ui/gitg-diff-view-commit-details.ui  |    2 +-
 libgitg/resources/ui/gitg-diff-view.ui             |   27 +++++++++++++++-
 libgitg/resources/ui/libgitg-style.css             |    5 +++
 5 files changed, 68 insertions(+), 5 deletions(-)
---
diff --git a/libgitg/gitg-diff-view-commit-details.vala b/libgitg/gitg-diff-view-commit-details.vala
index 0e53b27..3927d83 100644
--- a/libgitg/gitg-diff-view-commit-details.vala
+++ b/libgitg/gitg-diff-view-commit-details.vala
@@ -35,8 +35,8 @@ class Gitg.DiffViewCommitDetails : Gtk.Grid
        [GtkChild( name = "label_committer_date" )]
        private Gtk.Label d_label_committer_date;
 
-       [GtkChild( name = "label_message" )]
-       private Gtk.Label d_label_message;
+       [GtkChild( name = "label_subject" )]
+       private Gtk.Label d_label_subject;
 
        [GtkChild( name = "label_sha1" )]
        private Gtk.Label d_label_sha1;
@@ -185,7 +185,7 @@ class Gitg.DiffViewCommitDetails : Gtk.Grid
                        return;
                }
 
-               d_label_message.label = commit.get_message();
+               d_label_subject.label = commit.get_subject();
                d_label_sha1.label = commit.get_id().to_string();
 
                var author = commit.get_author();
diff --git a/libgitg/gitg-diff-view.vala b/libgitg/gitg-diff-view.vala
index 2ebcdd0..fedde41 100644
--- a/libgitg/gitg-diff-view.vala
+++ b/libgitg/gitg-diff-view.vala
@@ -38,6 +38,9 @@ public class Gitg.DiffView : Gtk.Grid
        [GtkChild( name = "diff_view_options" )]
        private DiffViewOptions d_diff_view_options;
 
+       [GtkChild( name = "text_view_message" )]
+       private Gtk.TextView d_text_view_message;
+
        private Ggit.Diff? d_diff;
        private Commit? d_commit;
        private Ggit.DiffOptions? d_options;
@@ -217,6 +220,29 @@ public class Gitg.DiffView : Gtk.Grid
                }
        }
 
+       private static Regex s_message_regexp;
+
+       static construct
+       {
+               try
+               {
+                       s_message_regexp = new Regex(".*[\\R\\s]*(?P<message>(?:.|\\R)*?)\\s*$");
+               } catch (Error e) { stderr.printf(@"Failed to compile regex: $(e.message)\n"); }
+       }
+
+       private string message_without_subject(Commit commit)
+       {
+               var message = commit.get_message();
+               MatchInfo minfo;
+
+               if (s_message_regexp.match(message, 0, out minfo))
+               {
+                       return minfo.fetch_named("message");
+               }
+
+               return "";
+       }
+
        private void update(bool preserve_expanded)
        {
                // If both `d_diff` and `d_commit` are null, clear
@@ -262,11 +288,18 @@ public class Gitg.DiffView : Gtk.Grid
 
                        d_diff = d_commit.get_diff(options, parent);
                        d_commit_details.show();
+
+                       var message = message_without_subject(d_commit);
+
+                       d_text_view_message.buffer.set_text(message);
+                       d_text_view_message.visible = (message != "");
                }
                else
                {
                        d_commit_details.commit = null;
                        d_commit_details.hide();
+
+                       d_text_view_message.hide();
                }
 
                if (d_diff != null)
diff --git a/libgitg/resources/ui/gitg-diff-view-commit-details.ui 
b/libgitg/resources/ui/gitg-diff-view-commit-details.ui
index f8d4b22..70c3a36 100644
--- a/libgitg/resources/ui/gitg-diff-view-commit-details.ui
+++ b/libgitg/resources/ui/gitg-diff-view-commit-details.ui
@@ -121,7 +121,7 @@
           </packing>
         </child>
         <child>
-          <object class="GtkLabel" id="label_message">
+          <object class="GtkLabel" id="label_subject">
             <property name="visible">True</property>
             <property name="can_focus">True</property>
             <property name="halign">start</property>
diff --git a/libgitg/resources/ui/gitg-diff-view.ui b/libgitg/resources/ui/gitg-diff-view.ui
index 76df5ec..8f534ef 100644
--- a/libgitg/resources/ui/gitg-diff-view.ui
+++ b/libgitg/resources/ui/gitg-diff-view.ui
@@ -41,11 +41,36 @@
                     <property name="visible">True</property>
                     <property name="can_focus">False</property>
                     <child>
-                      <object class="GtkGrid" id="grid_files">
+                      <object class="GtkGrid" id="grid_content">
                         <property name="visible">True</property>
                         <property name="orientation">vertical</property>
                         <property name="can_focus">False</property>
                         <property name="hexpand">True</property>
+                        <child>
+                          <object class="GtkTextView" id="text_view_message">
+                            <property name="visible">True</property>
+                            <property name="can_focus">True</property>
+                            <property name="editable">False</property>
+                            <property name="cursor_visible">False</property>
+                            <property name="hexpand">True</property>
+                            <property name="pixels_above_lines">1</property>
+                            <property name="pixels_below_lines">1</property>
+                            <property name="margin_bottom">6</property>
+                            <property name="margin_start">18</property>
+                            <property name="margin_end">18</property>
+                            <style>
+                              <class name="commit-message"/>
+                            </style>
+                          </object>
+                        </child>
+                        <child>
+                          <object class="GtkGrid" id="grid_files">
+                            <property name="visible">True</property>
+                            <property name="orientation">vertical</property>
+                            <property name="can_focus">False</property>
+                            <property name="hexpand">True</property>
+                          </object>
+                        </child>
                       </object>
                     </child>
                   </object>
diff --git a/libgitg/resources/ui/libgitg-style.css b/libgitg/resources/ui/libgitg-style.css
index 877a758..494e7fe 100644
--- a/libgitg/resources/ui/libgitg-style.css
+++ b/libgitg/resources/ui/libgitg-style.css
@@ -32,6 +32,11 @@ GitgDiffView GitgDiffViewCommitDetails {
        border-bottom: 1px outset lighter(@borders);
 }
 
+textview.commit-message text {
+       background-color: @theme_bg_color;
+       color: @theme_text_color;
+}
+
 gitg-diffstat {
        border: 1px inset shade(@borders, 1.2);
        border-radius: 5px;