# frozen_string_literal: true

##
# TB Preventive Therapy indicators for ART cohort
module MalawiHivProgramReports
  module Cohort
    class Tpt
      include MalawiHivProgramReports::Utils::CommonSqlQueryUtils
      include MalawiHivProgramReports::Adapters::Moh::Custom

      def initialize(start_date:, end_date:, **kwargs)
        @start_date = start_date
        @end_date = end_date
        @occupation = kwargs[:occupation]
        @location = kwargs[:location]
        @adapter = ActiveRecord::Base.connection.adapter_name.downcase
        return unless @occupation.present?

        process_occupation(start_date: @start_date, end_date: @end_date,
                           occupation: @occupation, location: @location)
      end

      ##
      # Patients (re-)initiated on 3HP in current reporting period.
      #
      # Candidates for this indicator are patients who either have
      # had their first dispensation in the current reporting period
      # or patients who have restarted 3HP in the current reporting
      # period after breaking from the course for a period of at least
      # 9 months (3 quarters).
      def newly_initiated_on_3hp
        # newly_initiated_on_tpt(start_date, end_date).each_with_object([]) do |patient, patients|
        #   patients << patient['patient_id'] unless patient_on_3hp?(patient)
        # end
        processed_tpt_clients.select { |patient| patient_on_3hp?(patient) }
      end

      ##
      # Patients (re-)initiated on IPT in current reporting period
      #
      # Has a similar definition to 3HP, please refer to 3HP docs
      # above.
      def newly_initiated_on_ipt
        # newly_initiated_on_tpt(start_date, end_date).each_with_object([]) do |patient, patients|
        #   patients << patient['patient_id'] if patient_on_3hp?(patient)
        # end
        processed_tpt_clients.reject { |patient| patient_on_3hp?(patient) }
      end

      private

      def patient_on_3hp?(patient)
        drug_concepts = patient['drug_concepts'].split(',').collect(&:to_i)
        drug_concepts.intersect?([rifapentine_concept.concept_id, three_hp_concept&.concept_id])
      end

      def rifapentine_concept
        @rifapentine_concept ||= ::ConceptName.find_by!(name: 'Rifapentine')
      end

      def three_hp_concept
        @three_hp_concept ||= ::ConceptName.find_by!(name: 'Isoniazid/Rifapentine')
      end

      def processed_tpt_clients
        @processed_tpt_clients ||= process_tpt_clients
      end

      def process_tpt_clients
        patients = []
        newly_initiated_on_tpt.each do |patient|
          course = patient['course'].include?('3HP') ? '3HP' : 'IPT'
          next if patient['last_course'].present?
          if patient['tpt_initial_start_date'].present? && patient['tpt_initial_start_date'].to_date < @start_date.to_date
            next
          end

          if patient['transfer_course'].blank? && patient['last_course'].blank?
            patients << patient
          elsif patient['transfer_course'].present? && patient['last_course'].blank?
            patients << patient if patient['months_since_tpt_transfer'].to_i >= (course == '3HP' ? 1 : 2)
          elsif patient['transfer_course'].blank? && patient['last_course'].present?
            patients << patient if patient['months_since_last_tpt'].to_i >= (course == '3HP' ? 1 : 2)
          elsif patient['last_tpt_end_date'].to_date >= patient['transfer_end_date'].to_date
            patients << patient if patient['months_since_last_tpt'].to_i >= (course == '3HP' ? 1 : 2)
          elsif patient['last_tpt_end_date'].to_date < patient['transfer_end_date'].to_date
            patients << patient if patient['months_since_tpt_transfer'].to_i >= (course == '3HP' ? 1 : 2)
          end
        end
        patients
      end

      def newly_initiated_on_tpt
        start_date = ActiveRecord::Base.connection.quote(@start_date)
        end_date = ActiveRecord::Base.connection.quote(@end_date)

        @newly_initiated_on_tpt ||= ActiveRecord::Base.connection.select_all <<~SQL
          SELECT
            cohort_patients.patient_id,
            cohort_patients.earliest_start_date,
            MIN(orders.start_date )as tpt_start_date,
            #{@adapter == 'mysql2' ? "GROUP_CONCAT(DISTINCT orders.concept_id SEPARATOR ',') AS drug_concepts," : "(SELECT STRING_AGG(concept_id::VARCHAR, ',') FROM (SELECT DISTINCT orders.concept_id FROM orders) AS subquery) AS drug_concepts,"}
            CASE
              WHEN count(distinct(orders.concept_id)) > 1 THEN '3HP old'
              WHEN orders.concept_id = #{three_hp_concept.concept_id} THEN '3HP new'
              ELSE '6H'
            END AS course,
            tpt_transfer_in_obs.value_datetime AS tpt_initial_start_date,
            CASE
              WHEN tpt_transfer_in_obs.concept_id IS NULL THEN NULL
              WHEN count(distinct(tpt_transfer_in_obs.concept_id)) > 1 THEN '3HP old'
              WHEN tpt_transfer_in_obs.concept_id = #{three_hp_concept.concept_id} THEN '3HP new'
              ELSE '6H'
            END AS transfer_course,
            tpt_transfer_in_obs.obs_datetime AS transfer_end_date,
            tpt_transfer_in_obs.value_numeric AS transfer_amount,
            #{@adapter == 'mysql2' ? 'TIMESTAMPDIFF(MONTH, tpt_transfer_in_obs.obs_datetime, MIN(orders.start_date)) AS months_since_tpt_transfer,' : '(EXTRACT(YEAR FROM AGE(MIN(orders.start_date), tpt_transfer_in_obs.obs_datetime)) * 12 + EXTRACT(MONTH FROM AGE(MIN(orders.start_date), tpt_transfer_in_obs.obs_datetime))) AS months_since_tpt_transfer,'}
            #{@adapter == 'mysql2' ? 'TIMESTAMPDIFF(MONTH, last_tpt_prescription.auto_expire_date, MIN(orders.start_date)) AS months_since_last_tpt,' : '(EXTRACT(YEAR FROM AGE(MIN(orders.start_date), last_tpt_prescription.auto_expire_date)) * 12 + EXTRACT(MONTH FROM AGE(MIN(orders.start_date), last_tpt_prescription.auto_expire_date))) AS months_since_last_tpt,'}
            last_tpt_prescription.course AS last_course,
            last_tpt_prescription.start_date AS last_tpt_start_date,
            last_tpt_prescription.auto_expire_date AS last_tpt_end_date
          FROM temp_earliest_start_date AS cohort_patients
          INNER JOIN orders
            ON orders.patient_id = cohort_patients.patient_id
            AND orders.order_type_id = (SELECT order_type_id FROM order_type WHERE name = 'Drug order' LIMIT 1)
            AND orders.start_date >= #{start_date}
            AND orders.start_date < #{interval_manager(date: end_date, value: 1, interval: 'DAY', operator: '+')}
            AND orders.voided = 0 #{site_manager(operator: 'AND', column: 'orders.site_id', location: @location)}
          INNER JOIN concept_name AS tpt_drug_concepts
            ON tpt_drug_concepts.concept_id = orders.concept_id
            AND tpt_drug_concepts.name IN ('Rifapentine', 'Isoniazid', 'Isoniazid/Rifapentine')
            AND tpt_drug_concepts.voided = 0
          INNER JOIN drug_order AS drug_orders
            ON drug_orders.order_id = orders.order_id
            AND drug_orders.quantity > 0 #{site_manager(operator: 'AND', column: 'drug_orders.site_id', location: @location)}
          INNER JOIN encounter
            /* Ensure we are dealing with ART prescriptions (Treatment encounter) */
            ON encounter.encounter_id = orders.encounter_id
            AND encounter.encounter_type = (SELECT encounter_type_id FROM encounter_type WHERE name = 'Treatment' LIMIT 1)
            AND encounter.program_id = (SELECT program_id FROM program WHERE name = 'HIV PROGRAM' LIMIT 1)
            AND encounter.voided = 0
          LEFT JOIN obs tpt_transfer_in_obs
            ON tpt_transfer_in_obs.person_id = orders.patient_id
            AND tpt_transfer_in_obs.concept_id = #{::ConceptName.find_by_name('TPT Drugs Received').concept_id}
            AND tpt_transfer_in_obs.voided = 0  #{site_manager(operator: 'AND', column: 'tpt_transfer_in_obs.site_id', location: @location)}
            AND tpt_transfer_in_obs.value_drug IN (SELECT drug_id FROM drug WHERE concept_id IN (SELECT concept_id FROM concept_name WHERE name IN ('Rifapentine', 'Isoniazid', 'Isoniazid/Rifapentine')))
          -- Get the last TPT prescription
          LEFT JOIN (
            SELECT
              o.patient_id,
              MAX(o.start_date) AS start_date,
              MAX(o.auto_expire_date) AS auto_expire_date,
              CASE
                WHEN count(distinct(o.concept_id)) > 1 THEN '3HP old'
                WHEN o.concept_id = #{three_hp_concept.concept_id} THEN '3HP new'
                ELSE '6H'
              END AS course
            FROM temp_earliest_start_date
            INNER JOIN orders o ON o.patient_id = temp_earliest_start_date.patient_id #{site_manager(operator: 'AND', column: 'o.site_id', location: @location)}
            INNER JOIN concept_name AS tpt_drug_concepts ON tpt_drug_concepts.concept_id = o.concept_id AND tpt_drug_concepts.name IN ('Rifapentine', 'Isoniazid', 'Isoniazid/Rifapentine') AND tpt_drug_concepts.voided = 0
            INNER JOIN drug_order AS drug_orders ON drug_orders.order_id = o.order_id AND drug_orders.quantity > 0 #{site_manager(operator: 'AND', column: 'drug_orders.site_id', location: @location)}
            INNER JOIN encounter ON encounter.encounter_id = o.encounter_id AND encounter.encounter_type = (SELECT encounter_type_id FROM encounter_type WHERE LOWER(name) = Lower('Treatment') LIMIT 1) AND encounter.program_id = (SELECT program_id FROM program WHERE LOWER(name) = LOWER('HIV Program') LIMIT 1) AND encounter.voided = 0
            WHERE o.voided = 0 #{site_manager(operator: 'AND', column: 'temp_earliest_start_date.site_id', location: @location)}
            AND o.start_date < #{start_date}
            GROUP BY o.patient_id, o.concept_id
          ) AS last_tpt_prescription ON last_tpt_prescription.patient_id = orders.patient_id
          GROUP BY cohort_patients.patient_id #{@adapter == 'mysql2' ? '' : ', tpt_transfer_in_obs.concept_id, tpt_transfer_in_obs.obs_datetime, tpt_transfer_in_obs.value_numeric, last_tpt_prescription.course, last_tpt_prescription.start_date, last_tpt_prescription.auto_expire_date, orders.concept_id, tpt_transfer_in_obs.value_datetime, tpt_transfer_in_obs.concept_id'}
        SQL
      end
    end
  end
end