Index: app/controllers/gantts_controller.rb
===================================================================
--- app/controllers/gantts_controller.rb	(revision 3764)
+++ app/controllers/gantts_controller.rb	(working copy)
@@ -1,5 +1,6 @@
 class GanttsController < ApplicationController
   before_filter :find_optional_project
+  before_filter :find_issue, :only => [:edit_gantt]
 
   rescue_from Query::StatementInvalid, :with => :query_statement_invalid
 
@@ -10,6 +11,7 @@
   helper :sort
   include SortHelper
   include Redmine::Export::PDF
+  include IssuesHelper
   
   def show
     @gantt = Redmine::Helpers::Gantt.new(params)
@@ -42,4 +44,82 @@
     end
   end
 
+  def find_optional_project
+    @project = Project.find(params[:project_id]) unless params[:project_id].blank?
+    if params[:action] == "edit_gantt"
+      allowed = User.current.allowed_to?({:controller => 'issues', :action => 'edit'}, @project, :global => true)
+    else
+      allowed = User.current.allowed_to?({:controller => params[:controller], :action => params[:action]}, @project, :global => true)
+    end
+    allowed ? true : deny_access
+  rescue ActiveRecord::RecordNotFound
+    render_404
+  end
+
+  def edit_gantt
+    if !@issue.start_date || !@issue.due_before
+      render :text=>l(:notice_locking_conflict), :status=>400
+      return
+    end
+    @issue.init_journal(User.current)
+    date_from = Date.parse(params[:date_from])
+    old_start_date = @issue.start_date
+    o = get_position(@issue, date_from, Date.parse(params[:date_to]), params[:zoom])
+    text_for_revert = "#{@issue.id}=#{format_date(@issue.start_date)},#{@issue.start_date},#{format_date(@issue.due_before)},#{@issue.due_before},#{o[0]},#{o[1]},#{o[2]},#{o[3]}"
+
+    if params[:day]
+      #bar moved
+      day = params[:day].to_i
+      duration = @issue.due_before - @issue.start_date
+      @issue.start_date = date_from + day
+      @issue.due_date = @issue.start_date + duration.to_i if @issue.due_date
+    elsif params[:start_date]
+      #start date changed
+      start_date = Date.parse(params[:start_date])
+      if @issue.start_date == start_date
+        render :text=>""
+        return #nothing has changed
+      end
+      @issue.start_date = start_date
+      @issue.due_date = start_date if @issue.due_date && start_date > @issue.due_date
+    elsif params[:due_date]
+      #due date changed
+      due_date = Date.parse(params[:due_date])
+      if @issue.due_date == due_date
+        render :text=>""
+        return #nothing has changed
+      end
+      @issue.due_date = due_date
+      @issue.start_date = due_date if due_date < @issue.start_date
+    end
+    fv = @issue.fixed_version
+    if fv && fv.effective_date && !@issue.due_date && fv.effective_date < @issue.start_date
+      @issue.start_date = old_start_date
+    end
+
+    begin
+      @issue.save!
+      o = get_position(@issue, date_from, Date.parse(params[:date_to]), params[:zoom])
+      text = "#{@issue.id}=#{format_date(@issue.start_date)},#{@issue.start_date},#{format_date(@issue.due_before)},#{@issue.due_before},#{o[0]},#{o[1]},#{o[2]},#{o[3]}"
+
+      #check dependencies
+      issues = @issue.all_precedes_issues
+      issues.each do |i|
+        o = get_position(i, date_from, Date.parse(params[:date_to]), params[:zoom])
+        text += "|#{i.id}=#{format_date(i.start_date)},#{i.start_date},#{format_date(i.due_before)},#{i.due_before},#{o[0]},#{o[1]},#{o[2]},#{o[3]}"
+      end
+      render :text=>text
+    rescue
+      render :text=>@issue.errors.full_messages.join("\n") + "|" + text_for_revert  , :status=>400
+    end
+  end
+
+private
+  def find_issue
+    @issue = Issue.find(params[:id], :include => [:project, :tracker, :status, :author, :priority, :category])
+    @project = @issue.project
+  rescue ActiveRecord::RecordNotFound
+    render_404
+  end
+
 end
Index: app/helpers/issues_helper.rb
===================================================================
--- app/helpers/issues_helper.rb	(revision 3764)
+++ app/helpers/issues_helper.rb	(working copy)
@@ -36,8 +36,8 @@
     @cached_label_priority ||= l(:field_priority)
     
     link_to_issue(issue) + "<br /><br />" +
-      "<strong>#{@cached_label_start_date}</strong>: #{format_date(issue.start_date)}<br />" +
-      "<strong>#{@cached_label_due_date}</strong>: #{format_date(issue.due_date)}<br />" +
+      "<strong>#{@cached_label_start_date}</strong>: <span id='tooltip_start_date_#{issue.id}'>#{format_date(issue.start_date)}</span><br />" +
+      "<strong>#{@cached_label_due_date}</strong>: <span id='tooltip_due_date_#{issue.id}'>#{format_date(issue.due_date)}</span><br />" +
       "<strong>#{@cached_label_assigned_to}</strong>: #{issue.assigned_to}<br />" +
       "<strong>#{@cached_label_priority}</strong>: #{issue.priority.name}"
   end
@@ -259,4 +259,26 @@
       end
     end
   end
+
+  def get_position(event, date_from, date_to, zoom_str)
+    zoom = zoom_str.to_i
+    i_start_date = (event.start_date >= date_from ? event.start_date : date_from )
+    i_end_date = (event.due_before <= date_to ? event.due_before : date_to )
+
+    i_done_date = event.start_date + ((event.due_before - event.start_date+1)*event.done_ratio/100).floor
+    i_done_date = (i_done_date <= date_from ? date_from : i_done_date )
+    i_done_date = (i_done_date >= date_to ? date_to : i_done_date )
+
+    i_late_date = [i_end_date, Date.today].min if i_start_date <= Date.today
+
+    i_left = ((i_start_date - date_from)*zoom).floor
+    i_left = 0 if i_left < 0
+    i_width = ((i_end_date - i_start_date + 1)*zoom).floor - 2                  # total width of the issue (- 2 for left and right borders)
+    i_width = 0 if i_width < 0
+    d_width = ((i_done_date - i_start_date)*zoom).floor - 2                     # done width
+    d_width = 0 if d_width < 0
+    l_width = i_late_date ? ((i_late_date - i_start_date+1)*zoom).floor - 2 : 0 # delay width
+    l_width = 0 if l_width < 0
+    return i_left, i_width, l_width, d_width
+  end
 end
Index: app/models/issue.rb
===================================================================
--- app/models/issue.rb	(revision 3764)
+++ app/models/issue.rb	(working copy)
@@ -415,6 +415,16 @@
     end
     dependencies
   end
+
+  def all_precedes_issues
+    dependencies = []
+    relations_from.each do |relation|
+      next unless relation.relation_type == IssueRelation::TYPE_PRECEDES
+      dependencies << relation.issue_to
+      dependencies += relation.issue_to.all_dependent_issues
+    end
+    dependencies
+  end
   
   # Returns an array of issues that duplicate this one
   def duplicates
Index: app/views/gantts/show.html.erb
===================================================================
--- app/views/gantts/show.html.erb	(revision 3764)
+++ app/views/gantts/show.html.erb	(working copy)
@@ -1,3 +1,4 @@
+<% include_calendar_headers_tags %>
 <h2><%= l(:label_gantt) %></h2>
 
 <% form_tag(params.merge(:month => nil, :year => nil, :months => nil), :id => 'query_form') do %>
@@ -38,7 +39,7 @@
 <% zoom = 1
 @gantt.zoom.times { zoom = zoom * 2 }
 
-subject_width = 330
+subject_width = 280
 header_heigth = 18
 
 headers_height = header_heigth
@@ -58,7 +59,106 @@
 g_height = [(20 * @gantt.events.length + 6)+150, 206].max
 t_height = g_height + headers_height
 %>
+<input type="hidden" name="_date_from" id="i_date_from" value="<%=h(@gantt.date_from)%>" />
+<input type="hidden" name="_date_to" id="i_date_to" value="<%=h(@gantt.date_to)%>" />
+<input type="hidden" name="zm" id="i_zm" value="<%=h(zoom)%>" />
+<script type='text/javascript'>
+  function issue_moved(elem) {
+    var id_str = elem.id.substring(3, elem.id.length);
+    var v_date_from = document.getElementById('i_date_from').getAttribute("value");
+    var v_date_to = document.getElementById('i_date_to').getAttribute("value");
+    var v_zm = document.getElementById('i_zm').getAttribute("value");
+    var url_str = '/issues/edit_gantt/' + id_str;
+    var day = parseInt(elem.style.left)/parseInt(v_zm);
+    new Ajax.Request(url_str, {asynchronous:true, evalScripts:true,
+      parameters: 'day='+day+'&date_from='+v_date_from+'&date_to='+v_date_to+'&zoom='+v_zm,
+      onSuccess:function(obj) {
+        change_dates(obj.responseText);
+      },
+      onFailure:function(obj) {
+        handle_failure(obj.responseText);
+      }
+    });
 
+  }
+  
+  function handle_failure(res_text) {
+    var text = res_text.split('|');
+    alert(text[0]);
+    if (text.length == 1) {
+      return;
+    }
+    change_dates(text[1]);//revert
+  }
+
+  function change_dates(issue_infos) {
+    if (!issue_infos) {
+      return;
+    }
+    var issue_list = issue_infos.split("|");
+    for (i = 0; i < issue_list.length; i++) {
+      change_date(issue_list[i]);
+    }
+  }
+
+  function change_date(text) {
+    if (!text) {
+      return;
+    }
+    var issue_info = text.split("=");
+    var elem_id = issue_info[0];
+    var vals = issue_info[1].split(',');
+    var start_date_elem = document.getElementById(elem_id + '_start_date_str');
+    if (!start_date_elem) {
+      //target not exists
+      return;
+    }
+    start_date_elem.innerHTML = vals[0];
+    var tooltip_start_date_elem = document.getElementById('tooltip_start_date_' + elem_id);
+    tooltip_start_date_elem.innerHTML = vals[0];
+    var due_date_elem = document.getElementById(elem_id + '_due_date_str');
+    due_date_elem.innerHTML = vals[2];
+    var tooltip_due_date_elem = document.getElementById('tooltip_due_date_' + elem_id);
+    tooltip_due_date_elem.innerHTML = vals[2];
+
+    var ev_elem = document.getElementById('ev_' + elem_id);
+    ev_elem.style.left = vals[4] + 'px';
+    ev_elem.style.width = (parseInt(vals[5])+100)+'px';
+    var todo_elem = document.getElementById('task_todo_' + elem_id);
+    todo_elem.style.width = vals[5] + 'px';
+    var late_elem = document.getElementById('task_late_' + elem_id);
+    if (late_elem) {
+      late_elem.style.width = vals[6] + 'px';
+      if (vals[6] == '0') {
+        late_elem.className = 'task task_none';
+      } else {
+        late_elem.className = 'task task_late';
+      }
+    }
+    var done_elem = document.getElementById('task_done_' + elem_id);
+    if (done_elem) {
+      done_elem.style.width = vals[7] + 'px';
+      if (vals[7] == '0') {
+        done_elem.className = 'task task_none';
+      } else {
+        done_elem.className = 'task task_done';
+      }
+    }
+    var task_elem = document.getElementById('task_task_' + elem_id);
+    if (task_elem) {
+      task_elem.style.left = (parseInt(vals[5])+5) + 'px';
+    }
+    var tooltip = document.getElementById("tt_" + elem_id);
+    tooltip.style.left = ev_elem.style.left;
+
+    //change calendar date
+    document.getElementById(elem_id+"_hidden_start_date").value = vals[1];
+    document.getElementById(elem_id+"_start_date").value = vals[1];
+    document.getElementById(elem_id+"_hidden_due_date").value = vals[3];
+    document.getElementById(elem_id+"_due_date").value = vals[3];
+  }
+</script>
+
 <table width="100%" style="border:0; border-collapse: collapse;">
 <tr>
 <td style="width:<%= subject_width %>px; padding:0px;">
@@ -88,9 +188,56 @@
 end %>
 </div>
 </td>
+<td style="width:225px; padding:0px;">
+<div style="position:relative;height:<%= t_height + 24 %>px;width:225px;">
+<div style="width:225px;height:<%= headers_height %>px;background: #eee;" class="gantt_hdr"></div>
+<div style="width:225px;height:<%= t_height %>px;border-left: 1px solid #c0c0c0;overflow:hidden;" class="gantt_hdr"></div>
+<%
+top = headers_height + 8
+@gantt.events.each do |i| %>
+  <div style="position: absolute;line-height:1.2em;height:16px;top:<%= top %>px;"><small>
+  <% if i.is_a? Issue %>
+    <span id="<%=i.id%>_start_date_str" style="font-size: 7pt;"><%= format_date(i.start_date) %></span>
+    <input type="hidden" size="12" id="<%=i.id%>_hidden_start_date" value="<%= i.start_date %>">
+    <input type="hidden" size="12" id="<%=i.id%>_start_date" value="<%= i.start_date %>"><%= calendar_for("#{i.id}_start_date") if i.is_a? Issue %>
+<script type="text/javascript">
+//<![CDATA[
+new Form.Element.Observer('<%=i.id%>_start_date', 0.25,
+  function(element, value) {
+    if (value == document.getElementById('<%=i.id%>_hidden_start_date').value) {
+      return ;
+    }
+    new Ajax.Request('<%=url_for(:controller=>:issues, :action => :edit_gantt, :id=>i.id, :date_from=>@gantt.date_from.strftime("%Y-%m-%d"), :date_to=>@gantt.date_to.strftime("%Y-%m-%d"), :zoom=>zoom, :escape => false) %>', {asynchronous:true, evalScripts:true, onFailure:function(request){handle_failure(request.responseText)}, onSuccess:function(request){change_dates(request.responseText)}, parameters:'start_date=' + encodeURIComponent(value)});
+  })
+//]]>
+</script>
+    <span id="<%=i.id%>_due_date_str" style="font-size: 7pt;<%= "color: blue;" unless i.due_date%>">
+      <%= format_date(i.due_before) %>
+    </span>
+    <input type="hidden" size="12" id="<%=i.id%>_hidden_due_date" value="<%= i.due_date %>">
+    <input type="hidden" size="12" id="<%=i.id%>_due_date" value="<%= i.due_date %>"><%= calendar_for("#{i.id}_due_date") if i.due_date%>
+<script type="text/javascript">
+//<![CDATA[
+new Form.Element.Observer('<%=i.id%>_due_date', 0.25,
+  function(element, value) {
+    if (value == document.getElementById('<%=i.id%>_hidden_due_date').value) {
+      return ;
+    }
+    new Ajax.Request('<%=url_for(:controller=>:issues, :action => :edit_gantt, :id=>i.id, :date_from=>@gantt.date_from.strftime("%Y-%m-%d"), :date_to=>@gantt.date_to.strftime("%Y-%m-%d"), :zoom=>zoom, :escape => false) %>', {asynchronous:true, evalScripts:true, onFailure:function(request){handle_failure(request.responseText)}, onSuccess:function(request){change_dates(request.responseText)}, parameters:'due_date=' + encodeURIComponent(value)});
+  })
+//]]>
+</script>
+  <% else %>
+    <span style="font-size: 7pt;"><%= format_date(i.start_date) %></span>
+  <% end %>
+  </small></div>
+<% top = top + 20
+end %>
+</div>
+</td>
 <td>
 
-<div style="position:relative;height:<%= t_height + 24 %>px;overflow:auto;">
+<div style="position:relative;height:<%= t_height + 24 %>px;overflow:auto;" id="gantt-container">
 <div style="width:<%= g_width-1 %>px;height:<%= headers_height %>px;background: #eee;" class="gantt_hdr">&nbsp;</div>
 <% 
 #
@@ -150,15 +297,17 @@
 	left = 0
 	height = g_height + header_heigth - 1
 	wday = @gantt.date_from.cwday
+        dt = @gantt.date_from
 	(@gantt.date_to - @gantt.date_from + 1).to_i.times do 
 	width =  zoom - 1
 	%>
 	<div style="left:<%= left %>px;top:37px;width:<%= width %>px;height:<%= height %>px;font-size:0.7em;<%= "background:#f1f1f1;" if wday > 5 %>" class="gantt_hdr">
-	<%= day_name(wday).first %>
+	<%=  "#{dt.day}<br>"if @gantt.zoom == 4 %><%= day_name(wday).first %>
 	</div>
 	<% 
 	left = left + width+1
 	wday = wday + 1
+        dt = dt + 1
 	wday = 1 if wday > 7
 	end
 end %>
@@ -169,37 +318,30 @@
 #
 top = headers_height + 10
 @gantt.events.each do |i| 
-  if i.is_a? Issue 
-	i_start_date = (i.start_date >= @gantt.date_from ? i.start_date : @gantt.date_from )
-	i_end_date = (i.due_before <= @gantt.date_to ? i.due_before : @gantt.date_to )
-	
-	i_done_date = i.start_date + ((i.due_before - i.start_date+1)*i.done_ratio/100).floor
-	i_done_date = (i_done_date <= @gantt.date_from ? @gantt.date_from : i_done_date )
-	i_done_date = (i_done_date >= @gantt.date_to ? @gantt.date_to : i_done_date )
-	
-	i_late_date = [i_end_date, Date.today].min if i_start_date < Date.today
-	
-	i_left = ((i_start_date - @gantt.date_from)*zoom).floor 	
-	i_width = ((i_end_date - i_start_date + 1)*zoom).floor - 2                  # total width of the issue (- 2 for left and right borders)
-	d_width = ((i_done_date - i_start_date)*zoom).floor - 2                     # done width
-	l_width = i_late_date ? ((i_late_date - i_start_date+1)*zoom).floor - 2 : 0 # delay width
-  css = "task " + (i.leaf? ? 'leaf' : 'parent')
+  if i.is_a? Issue
+    i_left, i_width, l_width, d_width = get_position(i, @gantt.date_from, @gantt.date_to, zoom)
 	%>
-	<div style="top:<%= top %>px;left:<%= i_left %>px;width:<%= i_width %>px;" class="<%= css %> task_todo"><div class="left"></div>&nbsp;<div class="right"></div></div>
-	<% if l_width > 0 %>
-	    <div style="top:<%= top %>px;left:<%= i_left %>px;width:<%= l_width %>px;" class="<%= css %> task_late">&nbsp;</div>
-	<% end %>
-	<% if d_width > 0 %>
-	    <div style="top:<%= top %>px;left:<%= i_left %>px;width:<%= d_width %>px;" class="<%= css %> task_done">&nbsp;</div>
-	<% end %>
-	<div style="top:<%= top %>px;left:<%= i_left + i_width + 8 %>px;background:#fff;" class="<%= css %>">
-	<%= i.status.name %>
-	<%= (i.done_ratio).to_i %>%
-	</div>
-	<div class="tooltip" style="position: absolute;top:<%= top %>px;left:<%= i_left %>px;width:<%= i_width %>px;height:12px;">
-	<span class="tip">
+  <div id="ev_<%=i.id%>" style="position:absolute;left:<%= i_left %>px;top:<%= top %>px;padding-top:3px;height:18px;width:<%= i_width+100 %>px;" class="handle">
+    <div id="task_todo_<%=i.id%>" style="float:left:0px; width:<%= i_width %>px;" class="task task_todo">&nbsp;</div>
+    <div id="task_late_<%=i.id%>" style="float:left:0px; width:<%= l_width %>px;" class="<%= l_width == 0 ? 'task task_none' : 'task task_late' %>">&nbsp;</div>
+    <div id="task_done_<%=i.id%>" style="float:left:0px; width:<%= d_width %>px;" class="<%= d_width == 0 ? 'task task_none' : 'task task_done' %>">&nbsp;</div>
+    <div id="task_task_<%=i.id%>" style="position:absolute;left:<%= (i_width + 5) %>px;background:#fff;" class="task">
+    <%= h(i.status.name) %>
+    <%= (i.done_ratio).to_i %>%
+    <% if !i.due_date && i.fixed_version %>
+      -&nbsp;<strong><%= h(i.fixed_version.name)  %></strong>
+    <% end %>
+    </div>
+  </div>
+	<%# === tooltip === %>
+	<div id="tt_<%=i.id%>" class="tooltip" style="position: absolute;top:<%= top+14 %>px;left:<%= i_left %>px;width:<%= i_width %>px;height:8px;">
+	<span class="tip" style="position: relative;top:-2px;">
     <%= render_issue_tooltip i %>
 	</span></div>
+  <%= draggable_element("ev_#{i.id}",
+    :revert =>false, :scroll=>"'gantt-container'", :constraint => "'horizontal'", :snap=>zoom,
+       :onEnd=>"function( draggable, event )  {issue_moved(draggable.element);}"
+    ) %>
 <% else 
     i_left = ((i.start_date - @gantt.date_from)*zoom).floor
     %>
Index: config/routes.rb
===================================================================
--- config/routes.rb	(revision 3764)
+++ config/routes.rb	(working copy)
@@ -111,6 +111,7 @@
       issues_views.connect 'projects/:project_id/issues.:format', :action => 'index'
       issues_views.connect 'projects/:project_id/issues/new', :action => 'new'
       issues_views.connect 'projects/:project_id/issues/gantt', :controller => 'gantts', :action => 'show'
+      issues_views.connect 'projects/:project_id/issues/edit_gantt/:id', :controller => 'gantts', :action => 'edit_gantt', :id => /\d+/
       issues_views.connect 'projects/:project_id/issues/calendar', :controller => 'calendars', :action => 'show'
       issues_views.connect 'projects/:project_id/issues/:copy_from/copy', :action => 'new'
       issues_views.connect 'issues/:id', :action => 'show', :id => /\d+/
@@ -122,6 +123,7 @@
       issues_actions.connect 'issues', :action => 'index'
       issues_actions.connect 'projects/:project_id/issues', :action => 'create'
       issues_actions.connect 'projects/:project_id/issues/gantt', :controller => 'gantts', :action => 'show'
+      issues_actions.connect 'projects/:project_id/issues/edit_gantt:id', :controller => 'gantts', :action => 'edit_gantt', :id => /\d+/
       issues_actions.connect 'projects/:project_id/issues/calendar', :controller => 'calendars', :action => 'show'
       issues_actions.connect 'issues/:id/quoted', :action => 'reply', :id => /\d+/
       issues_actions.connect 'issues/:id/:action', :action => /edit|move|destroy/, :id => /\d+/
@@ -135,6 +137,7 @@
       issues_actions.connect 'issues/:id.:format', :action => 'destroy', :id => /\d+/, :format => /xml/
     end
     issues_routes.connect 'issues/gantt', :controller => 'gantts', :action => 'show'
+    issues_routes.connect 'issues/edit_gantt/:id', :controller => 'gantts', :action => 'edit_gantt', :id => /\d+/
     issues_routes.connect 'issues/calendar', :controller => 'calendars', :action => 'show'
     issues_routes.connect 'issues/:action'
   end
Index: public/stylesheets/application.css
===================================================================
--- public/stylesheets/application.css	(revision 3764)
+++ public/stylesheets/application.css	(working copy)
@@ -788,6 +788,7 @@
 .task_late { background:#f66 url(../images/task_late.png); border: 1px solid #f66; }
 .task_done { background:#66f url(../images/task_done.png); border: 1px solid #66f; }  
 .task_todo { background:#aaa url(../images/task_todo.png); border: 1px solid #aaa; }
+.task_none { background:transparent; border-style: none; }
 
 .task_todo.parent { background: #888; border: 1px solid #888; height: 6px;}
 .task_late.parent, .task_done.parent { height: 3px;}