class BookingTemplate < ActiveRecord::Base
  # Access restrictions
  attr_accessible :title, :code, :amount, :amount_relates_to, :comments, :charge_rate_code

  # Associations
  belongs_to :debit_account, :foreign_key => 'debit_account_id', :class_name => "Account"
  attr_accessible :debit_account_id, :debit_account
  belongs_to :credit_account, :foreign_key => 'credit_account_id', :class_name => "Account"
  attr_accessible :credit_account_id, :credit_account

  has_many :bookings, :through => :line_items

  # Default ordering
  default_scope order(:code)

  # Scopes
  scope :by_type, lambda{|value| where("code LIKE ?", value + ':%')}

  # Standard methods
  include ApplicationHelper
  def to_s(format = :default)
    case format
    when :short
      "%s / %s %s" % [
        debit_account ? debit_account.to_s(:short) : '?',
        credit_account ? credit_account.to_s(:short) : '?',
        amount ? "%0.2f" % amount.to_f : '?',
      ]
    when :long
      "%s an %s %s, %s (%s)" % [
        debit_account ? debit_account.to_s : '?',
        credit_account ? credit_account.to_s : '?',
        amount ? "%0.2f" % amount.to_f : '?',
        title.present? ? title : '?',
        comments.present? ? comments : '?'
      ]
    else
      title
    end
  end

  def amount_to_s
    if amount_relates_to.present?
      return "%.2f%%" % (amount.to_f * 100)
    else
      return currency_fmt(amount)
    end
  end

  # Tagging
  # =======
  if defined?(ActsAsTaggableOn) && ActsAsTaggableOn::Tag.table_exists?
    acts_as_taggable
    attr_accessible :tag_list

    acts_as_taggable_on :include_in_saldo
  end

  def booking_parameters(params = {})
    params = HashWithIndifferentAccess.new(params)

    # Prepare parameters set by template
    booking_params = attributes.reject{|key, value| !["title", "comments", "credit_account_id", "debit_account_id"].include?(key)}

    # Calculate amount
    booking_amount = BigDecimal.new(self.amount.to_s || '0')

    # Lookup reference
    reference = params['reference']
    unless reference
      ref_type = params['reference_type']
      ref_id = params['reference_id']
      if ref_type.present? and ref_id.present?
        reference = ref_type.constantize.find(ref_id)
      end
    end

    person_id = params.delete(:person_id)

    if reference
      # Calculate amount
      booking_amount = amount(reference.value_date, :person_id => person_id) if person_id

      case self.amount_relates_to
        when 'reference_amount'
          booking_amount *= reference.amount unless reference.amount.nil?
        when 'reference_balance'
          booking_amount *= reference.balance unless reference.balance.nil?
        when 'reference_amount_minus_balance'
          booking_amount *= reference.amount - reference.balance unless (reference.amount.nil? or reference.balance.nil?)
      end
    end

    booking_amount = booking_amount.try(:round, 2)
    booking_params['amount'] = booking_amount

    # Override by passed in parameters
    HashWithIndifferentAccess.new(booking_params.merge!(params))
  end

  # Factory methods
  # ===============
  def build_booking(params = {})
    Booking.new(booking_parameters(params))
  end

  def create_booking(params = {})
    Booking.create(booking_parameters(params))
  end

  # Build booking for template
  #
  # Raises an exception if template for given [code] cannot be found.
  #
  # @param code [String] to lookup template
  # @param params [Hash] parameters to set on the Booking
  # @return [Booking] unsaved Booking
  def self.build_booking(code, params = {})
    template = find_by_code(code)
    raise "BookingTemplate not found for '#{code}'" unless template

    template.build_booking params
  end

  def self.create_booking(code, params = {})
    find_by_code(code).try(:create_booking, params)
  end

  # LineItems
  has_many :line_items

  def build_line_item
    if self.amount.match(/%/) or self.amount_relates_to.blank?
      line_item_class = LineItem
    else
      line_item_class = SaldoLineItem
    end

    line_item = line_item_class.new(
      :booking_template      => self,
      :title                 => self.title,
      :code                  => self.code,
      :credit_account        => self.credit_account,
      :debit_account         => self.debit_account,
      :position              => self.position,
      :include_in_saldo_list => self.include_in_saldo_list,
      :reference_code        => self.amount_relates_to
    )

    if self.amount.match(/%/)
      line_item.quantity = '%'
      line_item.times    = self.amount.delete('%')
      # TODO: hack
      line_item.price    = line_item.price
    elsif self.amount_relates_to.present?
      line_item.quantity = 'saldo_of'
      # TODO: hack
      line_item.price    = line_item.price
    else
      line_item.quantity = 'x'
      line_item.times    = 1
      line_item.price    = self.amount
    end

    line_item
  end

  # Importer
  # ========
  attr_accessible :matcher

  def self.import(struct)
    templates = self.all.inject([]) do |found, template|
      puts "matcher: " + template.matcher
      puts 'text: ' + struct.text
      found << template if not Regexp.new(template.matcher).match(struct.text).eql?nil
    end
    puts templates.inspect
  end
end