require "dsiemailhelper/version"
require 'timeout'
require 'gmail'


module DSIEmailHelper
  
  HTTPS_REGEXP = /https?:\/\/[\S]+/

  def self.connect
    # using connect! because only it will throw an exception if an error occurs
    # during the connection process with gmail
    raise "Please ensure QA_INBOX_EMAIL and QA_INBOX_PASSWORD env vars are configured" unless ENV['QA_INBOX_EMAIL'] && ENV['QA_INBOX_PASSWORD']
    @inbox = Gmail.connect!(ENV['QA_INBOX_EMAIL'], ENV['QA_INBOX_PASSWORD'])
  end

  def self.get_all_emails
    # returns an array of Message objects
    @inbox.inbox.emails
  end

  def self.find_email_by_gmail_search(search_string, start_time, acceptable_offset=0)
    message = nil
    Timeout.timeout(120) do
      while filter_messages_by_time(@inbox.inbox.find(gm: search_string), start_time, acceptable_offset).length < 1
        sleep 0.5
      end
      message = filter_messages_by_time(@inbox.inbox.find(gm: search_string), start_time, acceptable_offset)[-1]
      message
    end
  rescue Timeout::Error => e
    puts "Search string passed: #{search_string}"
    puts "Start time passed: #{start_time} (offset: #{acceptable_offset})."
    puts "Messages matching search string: #{@inbox.inbox.find(gm: search_string)}"
    puts "Message: #{message || @inbox.inbox.find(gm: search_string)}"
    raise e
  end

  def self.filter_messages_by_time(messages, time, acceptable_offset=0)
    messages.delete_if { | message |
      message.message.date.to_time.to_f <= time.to_time.round.to_f - acceptable_offset
    }
    messages
  end

  def self.get_email_body(message)
    # expects a Message object and returns the body of the email without encoding
    message.text_part.body.decoded
  end

  def self.parse_link_from_body(decoded_message)
    decoded_message.scan(HTTPS_REGEXP)
  end

  def self.get_most_recent_email
    # Noticed the most recent email in the inbox folder always has the highest index,
    # so we can use the size of the array to determine what the most recent message is
    messages = get_all_emails
    messages[messages.length - 1]
  end

  def self.get_newest_password_reset_link(email)
    message = find_email_by_gmail_search("subject: Update Your Password to: #{email}", Date.today)
    body = get_email_body(message)
    # TODO: Archiving doesn't seem to be working, need to look into why
    message.delete!
    parse_link_from_body(body)
  end

end