# rubocop:disable Metrics/AbcSize, Metrics/MethodLength, Style/Documentation
# frozen_string_literal: true

require 'parallel'

module MalawiHivProgramReports
  module Pepfar
    class TxCurrMmd
      include Utils
      include MalawiHivProgramReports::Utils::CommonSqlQueryUtils
      include MalawiHivProgramReports::Adapters::Moh::Custom

      attr_accessor :report, :start_date, :end_date, :org, :location

      def initialize(start_date:, end_date:, **kwargs)
        @start_date = start_date.to_date.strftime('%Y-%m-%d 00:00:00')
        @end_date = end_date.to_date.strftime('%Y-%m-%d 23:59:59')
        @org = kwargs[:definition]
        @location = kwargs[:location]
        raise 'Location is required' if @location.blank?

        @report = init_report
      end

      def find_report
        process_data
        flatten_the_report
      rescue StandardError => e
        Rails.logger.error e.message
        Rails.logger.error e.backtrace.join("\n")
        raise e
      end

      private

      GENDER = %w[Male Female Unknown].freeze

      def init_report
        pepfar_age_groups.each_with_object({}) do |age_group, report|
          report[age_group] = GENDER.each_with_object({}) do |gender, age_group_report|
            age_group_report[gender] = {
              less_than_three_months: [],
              three_to_five_months: [],
              greater_than_six_months: []
            }
          end
        end
      end

      def process_age_group_report(age_group, gender, age_group_report)
        {
          age_group:,
          gender:,
          less_than_three_months: age_group_report[:less_than_three_months],
          three_to_five_months: age_group_report[:three_to_five_months],
          greater_than_six_months: age_group_report[:greater_than_six_months]
        }
      end

      def flatten_the_report
        result = []
        report.each do |age_group, age_group_report|
          age_group_report.each_key do |gender|
            result << process_age_group_report(age_group, gender, age_group_report[gender])
          end
        end

        new_group = pepfar_age_groups.map { |age_group| age_group }
        new_group << 'All'
        gender_scores = { 'Female' => 0, 'Male' => 1, 'FNP' => 3, 'FP' => 2, 'FBf' => 4 }
        result_scores = result.sort_by do |item|
          gender_score = gender_scores[item[:gender]] || 999
          age_group_score = new_group.index(item[:age_group]) || 999
          [gender_score, age_group_score]
        end
        # remove all unknown age groups
        result_scores.reject { |item| item[:age_group].match?(/unknown/i) }
      end

      def process_data
        patients = ActiveRecord::Base.connection.select_all <<~SQL
          SELECT tesd.patient_id,
              CASE tesd.gender
                WHEN 'M' THEN 'Male'
                WHEN 'F' THEN 'Female'
                ELSE 'Unknown'
              END gender,
              disaggregated_age_group(tesd.birthdate, '#{end_date}') age_group,
              TIMESTAMPDIFF(DAY, tcm.start_date, tcm.auto_expire_date) prescribed_days
          FROM cdr_temp_cohort_members #{current_partition} tesd#{' '}
          INNER JOIN cdr_temp_patient_outcomes #{current_partition} tpo ON tpo.patient_id = tesd.patient_id AND tpo.cum_outcome = 'On antiretrovirals'
          INNER JOIN cdr_temp_min_auto_expire_date #{current_partition} tcm ON tcm.patient_id = tesd.patient_id
          WHERE tesd.date_enrolled <= '#{end_date}'
        SQL

        return report if patients.blank?

        patients.each do |patient|
          prescribe_days = patient['prescribed_days'].to_i
          age_group = patient['age_group']
          gender = patient['gender']

          indicator = if prescribe_days < 90
                        'less_than_three_months'
                      elsif prescribe_days >= 90 && prescribe_days <= 150
                        'three_to_five_months'
                      elsif prescribe_days > 150
                        'greater_than_six_months'
                      end

          report[age_group][gender][indicator.to_sym] << patient['patient_id']
        end

        report
      end
    end
  end
end
# rubocop:enable Metrics/AbcSize, Metrics/MethodLength, Style/Documentation