# Mollie payment page
class Payments::MollieIdealController < ApplicationController
  before_action -> { require_plugin_enabled FoodsoftMollie }
  skip_before_action :authenticate, :only => [:check]
  skip_before_action :verify_authenticity_token, :only => [:check]
  before_action :accept_return_to, only: [:new]
  before_action :ordergroup, only: [:new, :create, :result]
  before_action :transaction, only: [:result]
  before_action :configure_api_key

  def new
    @amount = (params[:amount] or [0, -@ordergroup.get_available_funds].max)
    @amount = [params[:min], params[:amount]].max if params[:min]
  end

  def create
    # store parameters so we can redirect to original form on problems
    session[:mollie_params] = params.select { |k, _| %w[amount label title fixed min text].include?(k) }.to_h

    amount = params[:amount].to_f
    amount = [params[:min].to_f, amount].max if params[:min]

    # @todo check amount > transaction feex

    ft_type = FinancialTransactionType.find_by_id(FoodsoftConfig[:mollie][:financial_transaction_type]) || FinancialTransactionType.first

    @transaction = FinancialTransaction.create!(
      amount: nil,
      ordergroup: @ordergroup,
      user: @current_user,
      payment_plugin: 'mollie',
      payment_amount: amount,
      # @todo payment_currency
      payment_state: 'created',
      financial_transaction_type_id: ft_type.id,
      note: I18n.t('payments.mollie_ideal.controller.transaction_note', method: nil),

    )

    payment = Mollie::Payment.create(
      amount: {
        value: '%.2f' % [amount], # @todo use format over %
        currency: 'EUR' # @todo payment_currency
      },
      description: "#{@transaction.id}, #{@ordergroup.id}, #{FoodsoftConfig[:name]}",
      redirectUrl: result_payments_mollie_url(id: @transaction.id),
      webhookUrl: (request.local? ? check_payments_mollie_url : 'https://example.com'), # Mollie doesn't accept localhost here
      metadata: {
        scope: FoodsoftConfig.scope,
        transaction_id: @transaction.id,
        user: @current_user.id,
        ordergroup: @ordergroup.id
      }
    )
    @transaction.update payment_id: payment.id, payment_state: 'pending'

    logger.info "Mollie start: #{amount} for ##{@current_user.id} (#{@current_user.display})"

    redirect_to payment.checkout_url, allow_other_host: true
  rescue Mollie::Exception => e
    Rails.logger.info "Mollie create warning: #{e}"
    redirect_to new_payments_mollie_path(session[:mollie_params]), :alert => I18n.t('errors.general_msg', msg: e.message)
  end

  # Endpoint that Mollie calls when a payment status changes.
  def check
    logger.info "Mollie check: #{params[:id]}"
    @transaction = FinancialTransaction.find_by_payment_plugin_and_payment_id!('mollie', params[:id])
    logger.debug "  financial transaction: #{@transaction.inspect}"
    render plain: update_transaction(@transaction)
  rescue StandardError => e
    Rails.logger.error "Mollie check error: #{e}"
    render plain: "Error: #{e.message}"
  end

  # User is redirect here after payment
  def result
    update_transaction @transaction # @todo if request.local? # so localhost works too
    logger.info "Mollie result: transaction #{@transaction.id} (#{@transaction.payment_id}) is #{@transaction.payment_state}"
    case @transaction.payment_state
    when 'paid'
      redirect_to_return_or root_path, :notice => I18n.t('payments.mollie_ideal.controller.result.notice', amount: @transaction.amount, fee: @transaction.payment_fee)
    when 'pending'
      redirect_to_return_or root_path, :notice => I18n.t('payments.mollie_ideal.controller.result.wait')
    else
      payment_is_failed
    end
  end

  def payment_is_failed
    # redirect to form with same parameters as original page
    pms = { foodcoop: FoodsoftConfig.scope }.merge((session[:mollie_params] or {}))
    session[:mollie_params] = nil
    redirect_to new_payments_mollie_path(pms), :alert => I18n.t('payments.mollie_ideal.controller.result.failed') # TODO: recall check's response.message
  end

  def cancel
    redirect_to_return_or root_path
  end

  protected

  def ordergroup
    # @todo what if the current user doesn't have one?
    @ordergroup = current_user.ordergroup
  end

  def transaction
    @transaction = @ordergroup.financial_transactions.find(params[:id])
  end

  # @todo move this to ApplicationController, use it in SessionController too
  # @todo use a stack of return_to urls
  def accept_return_to
    session[:return_to] = nil # or else an unfollowed previous return_to may interfere
    return if params[:return_to].blank?

    return unless params[:return_to].starts_with?(root_path) || params[:return_to].starts_with?(root_url)

    session[:return_to] = params[:return_to]
  end

  def redirect_to_return_or(fallback_url, options = {})
    if session[:return_to].present?
      redirect_to_url = session[:return_to]
      session[:return_to] = nil
    else
      redirect_to_url = fallback_url
    end
    redirect_to redirect_to_url, options
  end

  # Query Mollie status and update financial transaction
  def update_transaction(transaction)
    payment = Mollie::Payment.get transaction.payment_id
    logger.debug "Mollie update_transaction: #{payment.inspect}"
    update_transaction_details(transaction, payment)
    update_transaction_amount(transaction, payment)
    payment.status
  end

  def update_transaction_amount(transaction, payment)
    if payment.status == 'paid'
      payment_fee = FoodsoftMollie.payment_fee payment.amount.value, transaction.payment_method
      amount = payment.amount.value.to_f - payment_fee.to_f
    end
    transaction.update payment_state: payment.status, amount: amount || 0, payment_fee: payment_fee || nil
  end

  def update_transaction_details(transaction, payment)
    if payment.details
      transaction.payment_acct_number = payment.details.consumerAccount
      transaction.payment_acct_name = payment.details.consumerName
    end
    transaction.payment_method = payment.method
    transaction.note = I18n.t('payments.mollie_ideal.controller.transaction_note', method: payment.method) # @todo add amount + fee to note
  end

  private

  def configure_api_key
    Mollie::Client.configure do |config|
      config.api_key = FoodsoftConfig[:mollie]['api_key']
    end
  end
end