From d6c3df1c3b09b6a73fbae61f725f6ab9524d8816 Mon Sep 17 00:00:00 2001
From: Gregory Trullemans <redj@MacBook-Pro-de-Gregory.local>
Date: Wed, 12 Jan 2022 21:03:43 +0100
Subject: [PATCH] Adding rebuil_tree command, breadcrumb and
 PrerequisiteClosure model/table

---
 .../management/commands/rebuild_tree.py       | 44 +++++++++++++++++
 ultron/objective/models.py                    | 49 +++++++++++++++++++
 ultron/objective/views.py                     | 10 +++-
 3 files changed, 102 insertions(+), 1 deletion(-)
 create mode 100644 ultron/objective/management/commands/rebuild_tree.py

diff --git a/ultron/objective/management/commands/rebuild_tree.py b/ultron/objective/management/commands/rebuild_tree.py
new file mode 100644
index 0000000000..471477a250
--- /dev/null
+++ b/ultron/objective/management/commands/rebuild_tree.py
@@ -0,0 +1,44 @@
+"""This command manages Closure Tables implementation
+  
+ It adds new levels and cleans links between Educatives.
+ This way, it's relatively easy to fetch an entire tree with just one tiny request.
+  
+ """
+  
+ from django.core.management.base import BaseCommand
+  
+ from ultron.objective.models import Educative, PrerequisiteClosure
+  
+  
+ class Command(BaseCommand):
+     def handle(self, *args, **options):
+         # educative_list = Educative.objects.all()
+         educative_list = [Educative.objects.get(pk=44)]
+  
+         for educative in educative_list:
+             # print('__________________________________________________________________________')
+             # print('Traitement de ' + str(educative))
+             # breadcrumb = [node for node in educative.breadcrumb()]
+             breadcrumb = educative.breadcrumb()
+  
+             for path in range(0, len(breadcrumb)):
+                 # print('  ˪ ' + str(path + 1) + 'ème chemin')
+                 tree = set(PrerequisiteClosure.objects.filter(descendant=educative, path=path))
+                 # print('    ' + str(tree))
+     
+                 for position, ancestor in enumerate(breadcrumb[path]):
+                     # print('    ˪ Traitement de ' + str(ancestor.long_label) + ' : ' + str(ancestor.long_label) + ' -> ' + str(educative.long_label) + ' | ' + str(position) + ' | ' + str(path))
+                     tree_path, _ = PrerequisiteClosure.objects.get_or_create(
+                         ancestor=ancestor, descendant=educative, level=position, path=path
+                     )
+                     # if _:
+                         # print('      -> CREATION : ' + str(tree_path))
+                     # else:
+                         # print('      -> RECUPERATION : ' + str(tree_path))
+     
+                     if tree_path in tree:
+                         tree.remove(tree_path)
+     
+                 for tree_path in tree:
+                     # print('      DELETE : ' + str(tree_path))
+                     tree_path.delete()
diff --git a/ultron/objective/models.py b/ultron/objective/models.py
index 5a4361877a..2dd8787d3d 100644
--- a/ultron/objective/models.py
+++ b/ultron/objective/models.py
@@ -78,6 +78,55 @@ class Educative(Markdownizable):
             self.level,
             self.difficulty,
         )
+ 
+    def breadcrumb(self, path=[]):
+        """
+        Renvoie le breadcrumb pour l'édutatif courant.
+        Exemple :
+            >>> s = Skill.objects.get(pk=44)
+            >>> s.breadcrumb()
+        """
+        # print('________________________________________________________________')
+        # print(self)
+        path = path + [self]
+        if self.prerequisites.all().count() == 0:
+            # print('Plus d\'ancetres')
+            return [path]
+
+        # print('# ancetres : ' + str(self.prerequisites.all().count()))
+        path_list = []
+        for prerequisite in self.prerequisites.all():
+            # print('    ' + str(prerequisite))
+            # Permet de gérer les cas de récursivité (qui ne devraient pas se produire dans notre cas)
+            if prerequisite.id == self.id:
+                return [self]
+            new_paths = prerequisite.breadcrumb(path)
+            for new_path in new_paths:
+                path_list.append(new_path)
+
+        return path_list
+
+
+class PrerequisiteClosure(models.Model):
+    """
+    Closure table de prérequis
+    """
+
+    class Meta:
+        unique_together = ("descendant", "ancestor", "level", "path")
+
+    descendant = models.ForeignKey(Educative, on_delete=models.CASCADE, related_name="ancestor")
+    ancestor = models.ForeignKey(Educative, on_delete=models.CASCADE, related_name="descendants")
+    level = models.PositiveIntegerField()
+    path = models.PositiveIntegerField()
+
+    def __str__(self):
+        return "%s -> %s (%s|%s)" % (
+            self.ancestor.long_label,
+            self.descendant.long_label,
+            self.level,
+            self.path
+        )
 
 
 class TouchPosition(models.Model):
diff --git a/ultron/objective/views.py b/ultron/objective/views.py
index d306aa3b01..4f41e54ac2 100644
--- a/ultron/objective/views.py
+++ b/ultron/objective/views.py
@@ -8,7 +8,12 @@ from django.urls import reverse
 from ultron.people.models import Gymnast
 
 from .forms import RoutineForm
-from .models import Skill, Routine, RoutineSkill
+from .models import (
+    Skill,
+    Routine,
+    RoutineSkill,
+    PrerequisiteClosure,
+)
 
 
 @login_required
@@ -70,6 +75,9 @@ def skill_tree(request, skill_id):
     """
     """
     skill = get_object_or_404(Skill, pk=skill_id)
+    print(skill)
+    skill_tree = PrerequisiteClosure.objects.filter(descendant=skill).order_by("path", "level")
+    print(skill_tree)
     context = {"skill": skill}
     return render(request, "objectives/skills/tree.html", context)