admin: do not allow to remove a status in use (#1241)

Instead, present the user with the possibility to reassign formdata to another
status, or to remove them.

wcs/admin/workflows.ptl

@@ -14,6 +14,8 @@
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, see <http://www.gnu.org/licenses/>.
 
+import time
+
 from quixote import redirect, get_publisher
 from quixote.directory import Directory
 
@@ -23,6 +25,8 @@ from qommon.form import *
 from qommon.admin.menu import html_top, command_icon, error_page
 
 from wcs.workflows import *
+from wcs.formdef import FormDef
+from wcs.formdata import Evolution
 from wcs.admin.forms import ET, indent
 
 
@@ -137,7 +141,8 @@ class WorkflowItemsDir(Directory):
         return redirect('..')
 
 class WorkflowStatusPage(Directory):
-    _q_exports = ['', 'delete', 'newitem', ('items', 'items_dir'), 'update_order', 'edit']
+    _q_exports = ['', 'delete', 'newitem', ('items', 'items_dir'),
+                  'update_order', 'edit', 'reassign']
 
     def __init__(self, workflow, status_id):
         self.workflow = workflow
@@ -253,6 +258,13 @@ class WorkflowStatusPage(Directory):
             '<h2>%s %s</h2>' % (_('Deleting Status:'), self.status.name)
             form.render()
         else:
+            # Before removing the status, scan formdata to know if it's in use.
+            for formdef in FormDef.select():
+                if formdef.workflow_id != self.workflow.id:
+                    continue
+                if formdef.data_class().get_with_indexed_value(
+                                str('status'), 'wf-%s' % self.status.id):
+                    return redirect('reassign')
             del self.workflow.possible_status[ self.workflow.possible_status.index(self.status) ]
             self.workflow.store()
             return redirect('../../')
@@ -281,6 +293,71 @@ class WorkflowStatusPage(Directory):
         '<h2>%s</h2>' % _('Edit Workflow Status')
         form.render()
 
+    def reassign [html] (self):
+        options = [(None, 'Do nothing'), ('remove', _('Remove'))]
+        for status in self.workflow.possible_status:
+            if status.id == self.status.id:
+                continue
+            options.append(('reassign-%s' % status.id, _('Change to "%s"') % status.name))
+
+        form = Form(enctype='multipart/form-data')
+        form.add(SingleSelectWidget, 'action', title=_('Pick an Action'),
+                 options=options)
+        form.add_submit('submit', _('Submit'))
+        form.add_submit('cancel', _('Cancel'))
+
+        if form.get_submit() == 'cancel':
+            return redirect('.')
+
+        if form.is_submitted() and not form.get_widget('action').parse():
+            return redirect('.')
+
+        if not form.is_submitted() or form.has_errors():
+            get_response().breadcrumb.append(('reassign', _('Reassign')))
+            html_top('workflows', title = _('Reassign'))
+            '<h2>%s</h2>' % _('Reassigning ')
+            '<p>'
+            _('''There are forms set to this status, they need to be changed before
+                 this status can be deleted.''')
+            '</p>'
+
+            '<ul>'
+            for formdef in FormDef.select():
+                if formdef.workflow_id != self.workflow.id:
+                    continue
+                items = formdef.data_class().get_with_indexed_value(
+                                str('status'), 'wf-%s' % self.status.id)
+                '<li>%s: %s</li>' % (formdef.name, _('%s items') % len(items))
+            '</ul>'
+
+            form.render()
+        else:
+            self.submit_reassign(form)
+            return redirect('.')
+
+    def submit_reassign(self, form):
+        action = form.get_widget('action').parse()
+        if action.startswith(str('reassign-')):
+            new_status = 'wf-%s' % str(action)[9:]
+        for formdef in FormDef.select():
+            if formdef.workflow_id != self.workflow.id:
+                continue
+            items = formdef.data_class().get_with_indexed_value(
+                            str('status'), 'wf-%s' % self.status.id)
+            for item in items:
+                if action == 'remove':
+                    item.remove_self()
+                else:
+                    item.status = new_status
+                    evo = Evolution()
+                    evo.time = time.localtime()
+                    evo.status = new_status
+                    evo.comment = _('Administrator reassigned status')
+                    if not item.evolution:
+                        item.evolution = []
+                    item.evolution.append(evo)
+                    item.store()
+
 
 class WorkflowStatusDirectory(Directory):
     _q_exports = ['']