module MailMerge
  TOKEN = /\{\{\s*([a-z0-9_.]+)\s*\}\}/i

  class << self
    def catalog
      {
        "societa" => "Nome società",
        "regione" => "Regione",
        "provincia" => "Provincia",
        "citta" => "Città",
        "email" => "Email",
        "sito" => "Sito / profilo",
        "sport" => "Sport",
        "mf" => "M/F",
        "streaming" => "Streaming rilevato",
        "fit" => "Fit commerciale",
        "n_lista" => "N. in lista",
        "contatto_nome" => "Nome contatto",
        "contatto_ruolo" => "Ruolo contatto",
        "contatto_email" => "Email contatto",
        "test_ab" => "Test A/B",
        "progetto" => "Nome progetto",
        "piano" => "Piano / prodotto"
      }
    end

    def variables_for(organization: nil, contact: nil, project: nil, opportunity: nil, ab_variant: nil)
      org = organization
      contact ||= org&.primary_contact || org&.contacts&.first
      opportunity ||= org&.campaign_opportunity(project) if org && project

      {
        "societa" => org&.name,
        "organizzazione.nome" => org&.name,
        "regione" => org&.region,
        "provincia" => org&.province,
        "citta" => org&.city,
        "email" => (contact&.email.presence || org&.email),
        "sito" => org&.website,
        "sport" => org&.sport,
        "mf" => org&.team_gender_label,
        "streaming" => org&.streaming_status_label,
        "fit" => org&.commercial_fit,
        "n_lista" => org&.list_position,
        "contatto_nome" => contact&.full_name,
        "contatto_ruolo" => contact&.role,
        "contatto_email" => contact&.email,
        "test_ab" => ab_variant.presence || opportunity&.ab_variant,
        "progetto" => project&.name,
        "piano" => opportunity&.product
      }.transform_values { |value| value.to_s }
    end

    def render(template, extras: {}, **context)
      vars = variables_for(**context)
      extras.each do |key, value|
        vars[key.to_s.downcase] = value.to_s
      end
      template.to_s.gsub(TOKEN) do
        key = Regexp.last_match(1).to_s.downcase
        vars[key].to_s
      end
    end
  end
end