Replace Gillick assessment patient session foreign key

This replaces the foreign key association between Gillick assessments
and patient sessions to instead link directly to the patient and the
session (via the date). This is needed as we eventually want to replace
the `PatientSession` model and to do that we need to make sure all
foreign keys to it have been replaced.

The functionality should be the same before and after, actually slightly
improved as Gillick assessment is only supposed to exist on the day it
happened, so now we link directly to the session date rather than the
overall session.

Jira-Issue: MAV-1818

Author: thomasleese

app/controllers/api/testing/teams_controller.rb

@@ -28,7 +28,6 @@ def destroy
         patient_ids = team.patients.pluck(:id)
 
         patient_sessions = PatientSession.where(session: sessions)
-        log_destroy(GillickAssessment.where(patient_session: patient_sessions))
         log_destroy(PreScreening.where(patient_session: patient_sessions))
         patient_sessions.in_batches { log_destroy(it) }
 
@@ -37,6 +36,7 @@ def destroy
         log_destroy(AccessLogEntry.where(patient_id: patient_ids))
         log_destroy(ArchiveReason.where(patient_id: patient_ids))
         log_destroy(ConsentNotification.where(patient_id: patient_ids))
+        log_destroy(GillickAssessment.where(patient_id: patient_ids))
         log_destroy(Note.where(patient_id: patient_ids))
         # In local dev we can end up with NotifyLogEntries without a patient
         log_destroy(NotifyLogEntry.where(patient_id: nil))

app/controllers/patient_sessions/gillick_assessments_controller.rb

@@ -1,6 +1,7 @@
 # frozen_string_literal: true
 
 class PatientSessions::GillickAssessmentsController < PatientSessions::BaseController
+  before_action :set_session_date
   before_action :set_gillick_assessment
 
   def edit
@@ -20,12 +21,19 @@ def update
 
   private
 
+  def set_session_date
+    @session_date = @session.session_dates.find_by!(value: Date.current)
+  end
+
   def set_gillick_assessment
     @gillick_assessment =
-      @patient_session
+      @patient
         .gillick_assessments
         .order(created_at: :desc)
-        .find_or_initialize_by(programme: @programme)
+        .find_or_initialize_by(
+          session_date: @session_date,
+          programme: @programme
+        )
   end
 
   def gillick_assessment_params

app/lib/patient_merger.rb

@@ -32,6 +32,10 @@ def call
         patient_id: patient_to_keep.id
       )
 
+      patient_to_destroy.gillick_assessments.update_all(
+        patient_id: patient_to_keep.id
+      )
+
       patient_to_destroy.school_moves.find_each do |school_move|
         if patient_to_keep.school_moves.exists?(
              home_educated: school_move.home_educated,
@@ -76,9 +80,6 @@ def call
                  session_id: patient_session.session_id
                )
            )
-          patient_session.gillick_assessments.update_all(
-            patient_session_id: existing_patient_session.id
-          )
           patient_session.pre_screenings.update_all(
             patient_session_id: existing_patient_session.id
           )

app/lib/reports/offline_session_exporter.rb

@@ -167,13 +167,17 @@ def consents
   def gillick_assessments
     @gillick_assessments ||=
       GillickAssessment
-        .select(
-          "DISTINCT ON (patient_session_id, programme_id) gillick_assessments.*"
+        .select("DISTINCT ON (patient_id, programme_id) gillick_assessments.*")
+        .joins(:session)
+        .where(
+          session_dates: {
+            session:
+          },
+          patient_id: patient_sessions.select(:patient_id)
         )
-        .where(patient_session: patient_sessions)
-        .order(:patient_session_id, :programme_id, created_at: :desc)
+        .order(:patient_id, :programme_id, created_at: :desc)
         .includes(:performed_by)
-        .group_by(&:patient_session_id)
+        .group_by(&:patient_id)
         .transform_values do
           it.group_by(&:programme_id).transform_values(&:first)
         end
@@ -244,8 +248,7 @@ def add_patient_cells(row, patient_session:, programme:)
     session = patient_session.session
 
     grouped_consents = consents.dig(patient.id, programme.id) || []
-    gillick_assessment =
-      gillick_assessments.dig(patient_session.id, programme.id)
+    gillick_assessment = gillick_assessments.dig(patient.id, programme.id)
     triage = triages.dig(patient.id, programme.id)
     academic_year = session.academic_year
 

app/lib/reports/programme_vaccinations_exporter.rb

@@ -147,22 +147,18 @@ def gillick_assessments
     @gillick_assessments ||=
       GillickAssessment
         .select(
-          "DISTINCT ON (patient_session_id) gillick_assessments.*, " \
-            "patient_sessions.patient_id, patient_sessions.session_id"
+          "DISTINCT ON (patient_id, session_id) gillick_assessments.*, session_id"
         )
-        .joins(:patient_session)
         .joins(:session)
         .where(
-          patient_sessions: {
-            patient_id: vaccination_records.select(:patient_id),
-            session_id: vaccination_records.select(:session_id)
-          },
+          patient_id: vaccination_records.select(:patient_id),
           programme:,
           session: {
+            id: vaccination_records.select(:session_id),
             academic_year:
           }
         )
-        .order(:patient_session_id, created_at: :desc)
+        .order(:patient_id, :session_id, created_at: :desc)
         .includes(:performed_by)
         .group_by(&:patient_id)
         .transform_values do

app/models/gillick_assessment.rb

@@ -13,34 +13,37 @@
 #  notes                :text             default(""), not null
 #  created_at           :datetime         not null
 #  updated_at           :datetime         not null
-#  patient_session_id   :bigint           not null
+#  patient_id           :bigint           not null
 #  performed_by_user_id :bigint           not null
 #  programme_id         :bigint           not null
+#  session_date_id      :bigint           not null
 #
 # Indexes
 #
-#  index_gillick_assessments_on_patient_session_id    (patient_session_id)
+#  index_gillick_assessments_on_patient_id            (patient_id)
 #  index_gillick_assessments_on_performed_by_user_id  (performed_by_user_id)
 #  index_gillick_assessments_on_programme_id          (programme_id)
+#  index_gillick_assessments_on_session_date_id       (session_date_id)
 #
 # Foreign Keys
 #
-#  fk_rails_...  (patient_session_id => patient_sessions.id)
+#  fk_rails_...  (patient_id => patients.id)
 #  fk_rails_...  (performed_by_user_id => users.id)
 #  fk_rails_...  (programme_id => programmes.id)
+#  fk_rails_...  (session_date_id => session_dates.id)
 #
 class GillickAssessment < ApplicationRecord
-  audited associated_with: :patient_session
+  audited associated_with: :patient
 
-  belongs_to :patient_session
+  belongs_to :patient
+  belongs_to :session_date
   belongs_to :programme
 
   belongs_to :performed_by,
              class_name: "User",
              foreign_key: :performed_by_user_id
 
-  has_one :patient, through: :patient_session
-  has_one :session, through: :patient_session
+  has_one :session, through: :session_date
 
   delegate :academic_year, to: :session
 

app/models/patient.rb

@@ -77,7 +77,7 @@ class Patient < ApplicationRecord
   has_many :vaccination_records, -> { kept }
   has_many :vaccination_statuses
 
-  has_many :gillick_assessments, through: :patient_sessions
+  has_many :gillick_assessments
   has_many :parents, through: :parent_relationships
   has_many :patient_specific_directions
   has_many :pre_screenings, through: :patient_sessions

app/models/patient_session.rb

@@ -44,7 +44,6 @@ class PatientSession < ApplicationRecord
   belongs_to :patient
   belongs_to :session
 
-  has_many :gillick_assessments
   has_many :pre_screenings
   has_many :session_attendances, dependent: :destroy
   has_one :registration_status
@@ -54,6 +53,10 @@ class PatientSession < ApplicationRecord
   has_one :team, through: :session
   has_one :organisation, through: :team
 
+  has_many :gillick_assessments,
+           -> { where(patient_id: it.patient_id) },
+           through: :session
+
   has_many :notes, -> { where(session_id: it.session_id) }, through: :patient
 
   has_one :latest_note,

app/models/session.rb

@@ -52,7 +52,7 @@ class Session < ApplicationRecord
   has_one :organisation, through: :team
   has_one :subteam, through: :location
   has_many :programmes, through: :session_programmes
-  has_many :gillick_assessments, through: :patient_sessions
+  has_many :gillick_assessments, through: :session_dates
   has_many :patients, through: :patient_sessions
   has_many :vaccines, through: :programmes
 

app/models/session_date.rb

@@ -21,6 +21,7 @@ class SessionDate < ApplicationRecord
 
   belongs_to :session
 
+  has_many :gillick_assessments, dependent: :restrict_with_error
   has_many :session_attendances, dependent: :restrict_with_error
 
   scope :for_session, -> { where("session_id = sessions.id") }