contribution.rb

# frozen_string_literal: true

# == Schema Information
#
# Table name: contributions
#
#  id             :bigint           not null, primary key
#  aasm_state     :string
#  amount         :integer          default(0)
#  error_message  :string
#  message        :text
#  mpesa_fees     :decimal(, )      default(0.0)
#  phone_number   :string
#  platform_fees  :decimal(, )      default(0.0)
#  source         :string
#  created_at     :datetime         not null
#  updated_at     :datetime         not null
#  campaign_id    :bigint
#  contributor_id :bigint
#
class Contribution < ApplicationRecord
  include AASM
  include PhoneNumberSanitizer

  scope :completed, -> { where(aasm_state: :completed) }

  FIXED_PLATFORM_FEES_RATE = 0.05

  #################### Enums ##############################

  #################### Associations #######################

  belongs_to :campaign
  belongs_to :contributor, class_name: :User

  has_one :payment_online_payment_request, class_name: 'Payment::OnlinePaymentRequest'
  has_one :payment_paybill_confirmation, class_name: 'Payment::PaybillConfirmation'

  #################### Validations ########################

  validates :amount, :source, presence: true
  validates :amount, numericality: { greater_than_or_equal_to: 1, only_integer: true }
  validates :phone_number, telephone_number: { country: proc { |_record| 'KE' }, types: %i[fixed_line mobile] }

  #################### Callbacks ##########################

  after_create :process_contribution

  #################### AASM State Machine #########################

  aasm do
    state :pending, initial: true
    state :processing
    state :completed
    state :failed

    event :process, after: :send_payment_request do
      transitions from: :pending, to: :processing
    end

    event :complete, after: :send_notifications do # Sending notifications after transition and charges applied, resource saved.
      transitions from: :processing, to: :completed, after: :apply_charges # Apply charges doesnt need to call save, it will be done after this transition before persisting the state
    end

    event :failure do
      transitions from: :processing, to: :failed, after: proc { |args| apply_failure_reason(args) }
    end

    after_all_transitions :log_status_change
  end

  #################### Object methods### ##################

  # AASM Callbacks

  def apply_charges
    rate = CalistoDefault.first&.platform_fees_rate
    rate ||= FIXED_PLATFORM_FEES_RATE
    self.platform_fees = amount * rate
    self.mpesa_fees = MpesaCharge.new(amount, campaign.fees_regime).call
    self
  end

  def send_notifications
    puts 'Sending contribution complete notifications'
    UserMailer.send_donation_processed(self).deliver_later
    UserMailer.send_donation_received(self).deliver_later
  end

  # dont forget to call comlete on the contribution!
  def self.from_paybill_confirmation(params)
    # Only create if corresponding campaign exists
    # Create user from phone number
    # Apply campaign and user to contribution
    # Will include user name
    campaign = Campaign.find_by(account_number: params['bill_ref_number'])

    if campaign.present?
      user = User.from_phone_number({ phone_number: params['msisdn'], name: "#{params['first_name']} #{params['middle_name']} #{params['last_name']}" })
      contribution = Contribution.create!(
        campaign: campaign,
        contributor: user,
        phone_number: params['msisdn'],
        amount: params['trans_amount'].to_i,
        source: 'mpesa-paybill',
        aasm_state: 'processing' # Doing this so that on save doesnt trigger a callback to request online payment
      )
      contribution.complete!
      contribution
    end
  end

  private

  def process_contribution
    ContributionWorker.perform_async({ phone: phone_number, amount: amount, id: id })
  end

  ######################### AASM State change callbacks #################

  def apply_failure_reason(message)
    puts "That failed: #{message}"
    self.error_message = message
    save
  end

  def send_payment_request
    # Guess this is where the online payment happens? ama?
    puts "Sending payment request...#{inspect}"
  end

  def log_status_change
    puts "Changed from #{aasm.from_state} to #{aasm.to_state} (event: #{aasm.current_event})"
  end
end