Update the workflow/phases api to simplify finding phases

opentech/apply/funds/templatetags/statusbar_tags.py

-from collections import defaultdict
 from django import template
 
 register = template.Library()
 
 
-def find_last_visible_phase(phases, user, current_phase):
-    last_phase = current_phase
-    while not last_phase.permissions.can_view(user):
-        last_phase = phases[last_phase.step - 1][0]
-    return last_phase
-
-
 @register.inclusion_tag('funds/includes/status_bar.html')
 def status_bar(workflow, current_phase, user, css_class='', same_stage=False):
 
-    all_phases = defaultdict(list)
-    for phase in list(workflow.values()):
-        all_phases[phase.step].append(phase)
+    phases = workflow.phases_for(user)
 
-    # Grab the first phase for each step - visible only, the display phase
-    phases = [
-        phase for phase, *_ in all_phases.values()
-        if phase.permissions.can_view(user)
-        and (not same_stage or phase.stage == current_phase.stage)
-    ]
+    if same_stage:
+        phases = [
+            phase for phase in phases
+            if phase.stage == current_phase.stage
+        ]
 
     if not current_phase.permissions.can_view(user):
-        current_phase = find_last_visible_phase(all_phases, user, current_phase)
+        current_phase = workflow.latest_visible(current_phase, user)
 
     # Current step not shown for user, move current phase to last good location
-    elif not all_phases[current_phase.step][0].permissions.can_view(user):
+    elif not workflow.stepped_phases[current_phase.step][0].permissions.can_view(user):
         new_phase_list = []
         for phase in reversed(phases):
             if phase.step <= current_phase.step and current_phase not in new_phase_list:

opentech/apply/funds/workflow.py

@@ -38,6 +38,29 @@ class Workflow(dict):
                 stages.append(phase.stage)
         return stages
 
+    @property
+    def stepped_phases(self):
+        phases = defaultdict(list)
+        for phase in list(workflow.values()):
+            all_phases[phase.step].append(phase)
+        return phases
+
+    def phases_for(self, user):
+        # Grab the first phase for each step - visible only, the display phase
+        phases = [
+            phase for phase, *_ in self.stepped_phases.values()
+            if phase.permissions.can_view(user)
+        ]
+
+    def previous_visible(self, current, user):
+        """Find the latest phase that the user has view permissions for"""
+        display_phase = self.stepped_phases[current.step][0]
+        phases = self.phases_for(user)
+        index = phases.index(current)
+        for phase in phases[index - 1::-1]:
+            if phase.permission.can_view(user):
+                return phase
+
 
 class Phase:
     def __init__(self, name, display, stage, permissions, step, public=None, transitions=dict()):