require 'xmpp4r'

### Some constants #########
::HELP_MESSAGE = "Unknown command. \n\n Please, use /login <phonenumber> to try log in. ☺"

#############################
## XMPP Transport Class #####
#############################
class XMPPComponent
    def initialize()
        @logger = Logger.new(STDOUT); @logger.progname = '[XMPPComponent]'
    end

    # transport initialization & connecting to XMPP server #
    def connect(params) # :jid => transport_jid, :host => xmpp_server, :port => xmpp_component_port, :secret => xmpp_component_secret
        @logger.info "Connecting.."
        begin
            @@transport = Jabber::Component.new( params[:jid] )
            @@transport.connect( params[:host], params[:port] )
            @@transport.auth( params[:secret] ) 
            @@transport.add_message_callback do |msg| msg.first_element_text('body') ? self.message_handler(msg) : nil  end 
            @sessions = {}
            @logger.info "Connection established"
            Thread.stop()
        rescue Exception => e
            @logger.info 'Connection failed: %s' % e
            exit 1
        end
    end
        
    # new message to XMPP component #
    def message_handler(msg)
        @logger.info 'New message from [%s] to [%s]' % [msg.from, msg.to]

        return self.process_internal_command(msg.from.bare, msg.first_element_text('body') ) if msg.to == @@transport.jid # treat message as internal command if received as transport jid
        return @sessions[msg.from.bare].queue_message(msg.to.to_s, msg.first_element_text('body')) if @sessions.key? msg.from.bare # queue message for processing session is active for jid from
    end
    
    # process internal /command #
    def process_internal_command(jfrom, body)
        case body.split[0] # /command argument = [command, argument]
        when '/login' 
            # we will try to create new user session for JID <jfrom> and try to start telegram client for login <body.split[1]>
            @sessions[jfrom] = XMPPSession.new(jfrom, body.split[1])
        when '/code', '/password'  
            # we will pass auth data to user session if this session exists. 
            @sessions[jfrom].enter_auth_data(body.split[0][1..8], body.split[1])  if @sessions.key? jfrom
        else # unknown command -- we will display sort of help message.
            reply = Jabber::Message.new; reply.from, reply.to, reply.body, reply.type = @@transport.jid, jfrom, ::HELP_MESSAGE, :chat 
            @@transport.send(reply) 
        end
    end
end 

#############################   
## XMPP Session Class #######
#############################

class XMPPSession < XMPPComponent
    attr_accessor :user_jid, :tg_login, :tg_auth_data, :message_queue
    
    # start XMPP user session and Telegram client instance #
    def initialize(jid, tg_login)
        @logger = Logger.new(STDOUT); @logger.progname = '[XMPPSession: %s/%s]' % [jid, tg_login]
        @logger.info "Starting Telegram session"
        @user_jid, @tg_login, @tg_auth_data, @message_queue = jid, tg_login, {code: nil, password: nil}, Queue.new()
        @tg_client = Thread.new{ TelegramClient.new(self, tg_login) }
    end
    
    # send message to XMPP  #
    def send_message(from = nil, body = '')
        @logger.info "Incoming message from Telegram network <- %s" % from.to_s
        from = from.nil? ? @@transport.jid : from.to_s+'@'+@@transport.jid.to_s
        reply = Jabber::Message.new; reply.from, reply.to, reply.body, reply.type = from, @user_jid, body, :chat 
        @@transport.send(reply)
    end    
    
    # queue message (we will share this queue within :message_queue to Telegram client thread) #
    def queue_message(to, text = '')
        @logger.info "Queuing message to be sent to Telegram network user -> " % to
        @message_queue << {to: to.split('@')[0], text: text}
        puts @message_queue
    end

    # enter auth data (we will share this data within :tg_auth_data to Telegram client thread ) #
    def enter_auth_data(typ, data) 
        logger.info "Authorizing in Telegram network with :%s" % typ
        @tg_auth_data[typ.to_sym] = data
    end 

end