require 'yaml'
# Copyright (c) 2008 Brendan G. Lim (brendangl@gmail.com)
# 
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
# 
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

module SMSFu
  RAILS_CONFIG_ROOT = defined?(RAILS_ROOT) ? "#{RAILS_ROOT}/config" : "#{File.dirname(__FILE__)}/../templates"
  @config = YAML::load(File.open("#{RAILS_CONFIG_ROOT}/sms_fu.yml"))
  @@carriers = @config['carriers']

  def deliver_sms(number,carrier,message,options={})
    number = format_number(number)
    raise SMSFuException.new("Cannot deliver an empty message to #{number}") if message.nil? or message.empty?
    
    options[:limit] ||= message.length
    message = message[0..options[:limit]-1]
    sms_email = determine_sms_email(format_number(number),carrier)
    
    SmsNotifier.deliver_sms_message(sms_email,message)
  rescue SMSFuException => exception
    raise exception
  end
  
  def get_sms_address(number,carrier)
    number = format_number(number)
    determine_sms_email(number,carrier)
  end
  
  private
  
  def format_number(number)
    pre_formatted = number.gsub("-","").strip
    formatted =  (pre_formatted.length == 11 && pre_formatted[0,1] == "1") ? pre_formatted[1..pre_formatted.length] : pre_formatted

    return is_valid?(formatted) ? formatted : (raise SMSFuException.new("Phone number (#{number}) is not formatted correctly"))
  end
  
  def is_valid?(number)
    return (number.length >= 10 && number[/^.\d+$/]) ? true : false
  end  
  
  def determine_sms_email(phone_number, carrier)
    if @@carriers.has_key?(carrier.downcase)
      "#{phone_number}#{@@carriers[carrier.downcase]}"
    else 
      raise SMSFuException.new("Specified carrier, #{carrier} is not supported.")
    end
  end 
       
  class SMSFuException < StandardError; end
end