Extracts a diff helper from the WikiDiff class.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@4952 e93f8b46-1217-0410-a6f0-8f06a7374b81

1 files changed, 72 insertions, 0 deletions

diff --git a/lib/redmine/helpers/diff.rb b/lib/redmine/helpers/diff.rb
new file mode 100644
index 000000000..24deb3d6d
--- /dev/null
+++ b/lib/redmine/helpers/diff.rb
@@ -0,0 +1,72 @@
+# Redmine - project management software
+# Copyright (C) 2006-2011  Jean-Philippe Lang
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+module Redmine
+  module Helpers
+    class Diff
+      include ERB::Util
+      include ActionView::Helpers::TagHelper
+      include ActionView::Helpers::TextHelper
+      attr_reader :diff, :words
+      
+      def initialize(content_to, content_from)
+        @words = content_to.to_s.split(/(\s+)/)
+        @words = @words.select {|word| word != ' '}
+        words_from = content_from.to_s.split(/(\s+)/)
+        words_from = words_from.select {|word| word != ' '}    
+        @diff = words_from.diff @words
+      end
+  
+      def to_html
+        words = self.words.collect{|word| h(word)}
+        words_add = 0
+        words_del = 0
+        dels = 0
+        del_off = 0
+        diff.diffs.each do |diff|
+          add_at = nil
+          add_to = nil
+          del_at = nil
+          deleted = ""      
+          diff.each do |change|
+            pos = change[1]
+            if change[0] == "+"
+              add_at = pos + dels unless add_at
+              add_to = pos + dels
+              words_add += 1
+            else
+              del_at = pos unless del_at
+              deleted << ' ' + h(change[2])
+              words_del  += 1
+            end
+          end
+          if add_at
+            words[add_at] = '<span class="diff_in">' + words[add_at]
+            words[add_to] = words[add_to] + '</span>'
+          end
+          if del_at
+            words.insert del_at - del_off + dels + words_add, '<span class="diff_out">' + deleted + '</span>'
+            dels += 1
+            del_off += words_del
+            words_del = 0
+          end
+        end
+        simple_format(words.join(' '))
+      end
+    end
+  end
+end