Aug 4 - Update code to follow up - MT12b

app/models/inspection_schedule.py

@@ -151,6 +151,26 @@ class InspectionSchedule(db.Model):
     mode         = db.Column(db.Enum('auto', 'plan'), nullable=False, default='auto')
     notes        = db.Column(db.Text, nullable=True)
 
+    # ── Follow-up link (phase48) ─────────────────────────────────────────────
+    # Set when this schedule was created as a follow-up of a specific completed
+    # inspection ("Schedule Follow-up" in the iPad's history detail — the
+    # deferred twin of "Re-inspect Now"). The inspection eventually started from
+    # this schedule inherits it as its own parent_inspection_id, so the run
+    # lands as a true linked re-inspection: pre-filled from the parent, and
+    # clearing the parent's follow_up_required on submit. NULL = an ordinary
+    # schedule, which is what every pre-phase48 row is.
+    parent_inspection_id = db.Column(
+        db.Integer,
+        # use_alter + an explicit name: inspections and inspection_schedules now
+        # reference each other, so metadata-driven CREATE/DROP cannot topologically
+        # sort them. The name matches the constraint phase48 creates, so the ORM's
+        # view of the schema and the migration's agree.
+        db.ForeignKey('inspections.id', ondelete='SET NULL',
+                      name='fk_inspection_schedules_parent_inspection',
+                      use_alter=True),
+        nullable=True, index=True,
+    )
+
     created_by   = db.Column(
         db.Integer, db.ForeignKey('users.id', ondelete='SET NULL'),
         nullable=True
@@ -196,6 +216,17 @@ class InspectionSchedule(db.Model):
     area      = db.relationship('Area',               foreign_keys=[area_id])
     inspector = db.relationship('User',               foreign_keys=[inspector_id])
     creator   = db.relationship('User',               foreign_keys=[created_by])
+    # phase48. Explicit foreign_keys is required, not optional: inspections and
+    # inspection_schedules now reference each other (Inspection
+    # .inspection_schedule_id points here, parent_inspection_id points back), so
+    # SQLAlchemy cannot infer the join for either side.
+    parent_inspection = db.relationship('Inspection',
+                                        foreign_keys=[parent_inspection_id])
+
+    @property
+    def is_follow_up(self):
+        """True when this schedule was created to follow up an inspection."""
+        return self.parent_inspection_id is not None
 
     FREQUENCY_LABELS = {
         'once':        'One-time',