require "lib/knife/knife_factory"
require "lib/puts_and_flush"
require "hooks"
require 'net/ssh'
require_relative "server_executor/expiration_scheduler"
require_relative 'server_executor/server_operation_result'

module Devops
  module Executor
    class ServerExecutor
      include Hooks
      include PutsAndFlush

      # waiting for 5*60 seconds (5 min)
      MAX_SSH_RETRIES_AMOUNT = 60

      #params:
      #  out - container for output data
      #  deploy_info - hash with deploy data
      define_hook :before_deploy
      define_hook :after_deploy

      define_hook :before_create
      define_hook :after_create

      #params:
      #  out - container for output data
      define_hook :before_bootstrap
      define_hook :after_bootstrap

      before_deploy :add_run_list_to_deploy_info


      attr_accessor :server, :deploy_env, :report, :project
      attr_reader :out

      def initialize server, out, options={}
        if server
          @project = Devops::Db.connector.project(server.project)
          @deploy_env = @project.deploy_env(server.deploy_env)
        end
        @server = server
        @out = out
        @out.class.send(:define_method, :flush) { } unless @out.respond_to?(:flush)
        @current_user = options[:current_user]
      end

      def error_code(reason)
        ServerOperationResult.code_of_reason(reason)
      end

      def create_server_object options
        Devops::Model::Server.new({
          "project" => @project.id,
          "deploy_env" => @deploy_env.identifier,
          "created_by" => options["created_by"],
          "provider" => @deploy_env.provider,
          "provider_account" => @deploy_env.provider_account,
          "private_ip" => options["private_ip"]
        })
      end

      def create_server options
        @server = create_server_object(options)
        @server.set_last_operation(Devops::Model::Server::OperationType::CREATION, options["created_by"])
        provider = @deploy_env.provider_instance
        mongo = ::Devops::Db.connector
        begin
          @out.puts "Using '#{@deploy_env.provider}' account '#{@deploy_env.provider_account}'\n" if @deploy_env.provider_account
          @out.puts "Create server..."
          @out.flush

          @server.run_list = options["run_list"] || []
          @server.chef_node_name = options["name"]
          @server.key = options["key"] || provider.ssh_key

          i = mongo.image(@deploy_env.image)
          @server.remote_user = i.remote_user

          res = {}
          @out << "\nBefore create hooks...\n"
          res[:before] = self.run_hook :before_create
          @out << "Done\n"

          unless provider.create_server(@server, @deploy_env.image, @deploy_env.flavor, @deploy_env.subnets, @deploy_env.groups, @out)
            return error_code(:creating_server_in_cloud_failed)
          end
          mongo.server_insert @server

          @out << "\nAfter create hooks...\n"
          res[:after] = self.run_hook :after_create
          @out << "Done\n"
          @out.flush
          DevopsLogger.logger.info "Server with parameters: #{@server.to_hash.inspect} is running"

          schedule_expiration()

          unless options["without_bootstrap"]
            bootstrap_options = { bootstrap_template: i.bootstrap_template }
            if @project.is_sandbox?
              bootstrap_options[:deployers] = [options['created_by']]
              bootstrap_options[:deployers] += (options['project_info']['deployers'] || []) if options['project_info']
            end
            return two_phase_bootstrap(bootstrap_options)
          else
            return 0
          end
        rescue => e
          @out.puts e.message
          @out.puts e.backtrace.join("\n")

          DevopsLogger.logger.error e.message
          roll_back
          mongo.server_delete @server.id
          error_code(:creating_server_unknown_error)
        end
      end

      # options:
      #   :run_list (optional)
      #   :bootstrap_template (optional)
      #   :chef_environment (optional)
      #   :config (optional)
      def bootstrap options
        @out << "\n\nBootstrap...\n"
        @out.flush
        k = Devops::Db.connector.key(@server.key)
        cert_path = k.path
        options[:cert_path] = k.path
        @out << "\nBefore bootstrap hooks...\n"
        res = self.run_hook(:before_bootstrap, @out)
        @out << "Done\n"
        if @server.private_ip.nil?
          @out.puts "Error: Private IP is null"
          return error_code(:server_bootstrap_private_ip_unset)
        end
        ja = {
          :provider => @server.provider,
          :provider_account => @server.provider_account,
          :devops_host => `hostname`.strip
        }
        ip = @server.private_ip
        unless @server.public_ip.nil?
          ip = @server.public_ip
          @out << "\nPublic IP is present\n"
        end

        address = "#{@server.remote_user}@#{ip}"

        cmd = check_ssh_command(cert_path, address)

        @out << "\nWaiting for SSH..."
        @out << "\nTest command: '#{cmd}'\n"
        @out.flush

        retries_amount = 0
        begin
          sleep(5)
          res = execute_system_command(cmd)
          retries_amount += 1
          if retries_amount >= MAX_SSH_RETRIES_AMOUNT
            @out.puts "Can not connect to #{address}"
            @out.puts res
            @out.flush
            DevopsLogger.logger.error "Can not connect with command '#{cmd}':\n#{res}"
            return error_code(:server_bootstrap_fail)
          end
          raise ArgumentError.new("Can not connect with command '#{cmd}' ") unless last_command_successful?
        rescue ArgumentError => e
          @out.puts "SSH command failed, retry (#{retries_amount}/#{MAX_SSH_RETRIES_AMOUNT})"
          @out.flush
          retry
        end

        provider = @server.provider_instance
        @server.chef_node_name = provider.create_default_chef_node_name(@server) if @server.chef_node_name.nil?

        r = knife_instance.knife_bootstrap(@out, ip, self.bootstrap_options(ja, options))

        if r == 0
          @out << "Chef node name: #{@server.chef_node_name}\n"
          ::Devops::Db.connector.server_set_chef_node_name @server
          @out << "Chef node name has been updated\n"
          @out << "After bootstrap hooks...\n"
          res = self.run_hook(:after_bootstrap, @out)
          @out << "Done\n"
          msg = "Server with id '#{@server.id}' is bootstraped"
          @out.puts msg
          @out.flush
          DevopsLogger.logger.info msg
          r
        else
          @out << "Can not bootstrap node '#{@server.id}', error code: #{r}"
          @out.flush
          error_code(:server_bootstrap_fail)
        end
      end

      # options:
      #   :cert_path (required)
      #   :run_list (optional)
      #   :bootstrap_template (optional)
      #   :chef_environment (optional)
      #   :config (optional)
      def bootstrap_options attributes, options
        bootstrap_options = [
          "-x #{@server.remote_user}",
          "-i #{options[:cert_path]}",
          "--json-attributes '#{attributes.to_json}'"
        ]
        bootstrap_options.push "-N #{@server.chef_node_name}" if @server.chef_node_name
        bootstrap_options.push "--sudo" unless @server.remote_user == "root"
        bootstrap_options.push "-t #{options[:bootstrap_template]}" if options[:bootstrap_template]
        bootstrap_options.push "-E #{options[:chef_environment]}" if options[:chef_environment]
        rl = options[:run_list]
        bootstrap_options.push "-r #{rl.join(",")}" unless rl.nil? or rl.empty?
        bootstrap_options.push "-c #{options[:config]}" if options[:config]
        bootstrap_options
      end

      def prepare_two_phase_bootstrap options
        @out << "Prepare bootstrap...\n"
        @out << "Done\n"
      end

      # essentially, it just bootstrap and then deploy
      def two_phase_bootstrap options
        prepare_two_phase_bootstrap(options)
        # bootstrap phase
        begin
          provider = @server.provider_instance
          mongo = ::Devops::Db.connector
          options[:run_list] = provider.run_list
          bootstrap_status = bootstrap(options)

          if bootstrap_status == 0
            if check_server_on_chef_server
              @out << "Server #{@server.chef_node_name} is created"
            else
              @out.puts "Can not find client or node on chef-server"
              @out.puts "Skip rollback because :skip_rollback option is set"
              roll_back unless options[:skip_rollback]
              @out.flush
              mongo.server_delete @server.id
              return error_code(:server_not_in_chef_nodes)
            end
          else
            @out.puts "Skip rollback because :skip_rollback option is set"
            roll_back unless options[:skip_rollback]
            mongo.server_delete @server.id
            msg = "Failed while bootstraping server with id '#{@server.id}'\n"
            msg << "Bootstraping operation result was #{bootstrap_status}"
            DevopsLogger.logger.error msg
            @out.puts msg
            @out.flush
            return error_code(:server_bootstrap_fail)
          end
        rescue => e
          @out << "\nError: #{e.message}\n"
          @out.flush
          return error_code(:server_bootstrap_unknown_error)
        end

        # deploy phase. Assume that all servers are bootstraped successfully here.
        begin
          run_list = compute_run_list
          @out << "\n\nComputed run list: #{run_list.join(", ")}"
          @out.flush
          knife_instance.set_run_list(@server.chef_node_name, run_list)
          deploy_info = options[:deploy_info] || @project.deploy_info(@deploy_env)
          deploy_info['project_info']['deployers'] = options[:deployers] if options[:deployers]
          deploy_status = deploy_server(deploy_info)
          if deploy_status == 0
            0
          else
            msg = "Failed on chef-client with run list, server with id '#{@server.id}'"
            msg << "\nDeploing server operation status was #{deploy_status}"
            DevopsLogger.logger.error msg
            @out << "\n" + msg + "\n"
            error_code(:deploy_failed)
          end
        rescue => e
          @out << "\nError: #{e.message}\n"
          DevopsLogger.logger.error(e.message + "\n" + e.backtrace.join("\n"))
          error_code(:deploy_unknown_error)
        end
      end

      def check_server_on_chef_server
        knife_instance.chef_node_list.include?(@server.chef_node_name) and knife_instance.chef_client_list.include?(@server.chef_node_name)
      end

      # returns a hash with :chef_node, :chef_client and :server keys
      def unbootstrap
        k = Devops::Db.connector.key(@server.key)
        cert_path = k.path
        i = 0
        res = delete_from_chef_server(@server.chef_node_name)
        begin
          new_name = "/etc/chef.backup_#{Time.now.strftime("%d-%m-%Y_%H.%M.%S")}"
          cmd = (@server.remote_user == 'root' ? "" : "sudo ")
          cmd = cmd + "/bin/sh -c 'if [[ -d /etc/chef ]]; then mv /etc/chef #{new_name} && echo ok; else echo not found; fi'"
          DevopsLogger.logger.info("SSH: trying to run command '#{cmd}'")
          Net::SSH.start(@server.private_ip, @server.remote_user, :keys => [cert_path]) do |session|
            session.open_channel do |channel|
              channel.request_pty(:modes => { Net::SSH::Connection::Term::ECHO => 0 }) do |c, success|
                raise "could not request pty" unless success
                channel.exec cmd
                channel.on_data do |c_, data|
                  if data == 'not found'
                    res[:server] = "Directory '/etc/chef' does not exists"
                  elsif data == 'ok'
                    res[:server] = "'/etc/chef' renamed to '#{new_name}'"
                  else
                    DevopsLogger.logger.error "Unexpected error: " + data
                    raise(data)
                  end
                end
              end
            end
          end
        rescue => e
          DevopsLogger.logger.error "Unbootstrap error: " + e.message
          i += 1
          sleep(1)
          retry unless i == 5
          return {error: e.message}
        end
        res
      end

      def deploy_server_with_tags tags, deploy_info
        return deploy_server(deploy_info) if tags.empty?

        old_tags_str = knife_instance.tags_list(@server.chef_node_name).join(" ")
        new_tags_str = tags.join(" ")

        @out.puts "Temporarily changing tags (#{old_tags_str}) to (#{new_tags_str})"
        unless knife_instance.swap_tags(@server.chef_node_name, old_tags_str, new_tags_str)
          m = "Error: Cannot add tags '#{new_tags_str}' to server '#{@server.chef_node_name}'"
          DevopsLogger.logger.error(m)
          @out.puts m
          return error_code(:server_cannot_update_tags)
        end
        DevopsLogger.logger.info("Set tags for '#{@server.chef_node_name}': #{new_tags_str}")

        begin
          deploy_result = deploy_server deploy_info
        ensure
          @out.puts "Restoring tags"
          knife_instance.swap_tags(@server.chef_node_name, new_tags_str, old_tags_str)
          DevopsLogger.logger.info("Restoring tags for #{@server.chef_node_name}: from #{new_tags_str} back to (#{old_tags_str})")
        end
        deploy_result
      end

      def deploy_server deploy_info
        @out << "\nBefore deploy hooks...\n"
        res = self.run_hook(:before_deploy, @out, deploy_info)
        @out << "Done\n"
        @out << "\nRun chef-client on '#{@server.chef_node_name}'\n"
        cmd = "chef-client --no-color"
        if deploy_info["use_json_file"]
          deploy_info.delete("use_json_file")
          json = nil
          dir = DevopsConfig.config[:project_info_dir]
          file = deploy_info.delete("json_file") || "#{@server.project}_#{@server.deploy_env}_#{Time.new.to_i}"
          path = File.join(dir, file)
          if File.exists?(path)
            json = File.read(path)
          else
            json = JSON.pretty_generate(deploy_info)
            File.open(File.join(dir, file), "w") do |f|
              f.write json
            end
          end
          @out.puts "Deploy Input Parameters:"
          @out.puts json
          @out.flush
          cmd << " -j http://#{DevopsConfig.config[:address]}:#{DevopsConfig.config[:port]}/#{DevopsConfig.config[:url_prefix]}/v2.0/deploy/data/#{file}"
        else
          if deploy_info['named_task'].present?
            named_task = @project.named_tasks.detect {|task| task['name'] == deploy_info['named_task']}
            raise "Named task #{deploy_info['named_task']} doesn't exist." unless named_task
            puts_and_flush "Using named task #{deploy_info['named_task']}."
            cmd << " -o #{named_task['run_list'].join(',')}"
          else
            cmd << " -r #{deploy_info["run_list"].join(",")}" unless @server.stack.nil?
          end
        end
        ip = if @server.public_ip.nil?
          @server.private_ip
        else
          @out << "Public IP detected\n"
          @server.public_ip
        end
        @out.flush
        k = Devops::Db.connector.key(@server.key)
        lline = knife_instance.ssh_stream(@out, cmd, ip, @server.remote_user, k.path)
        r = /Chef\sClient\sfinished/i

        if lline && lline[r]
          @out << "\nAfter deploy hooks...\n"
          res = self.run_hook(:after_deploy, @out, deploy_info)
          @out << "Done\n"

          @server.set_last_operation(Devops::Model::Server::OperationType::DEPLOY, @current_user)
          Devops::Db.connector.server_update(@server)

          0
        else
          @out << "An error occured during knife command executing"
          1
        end
      end

      def delete_from_chef_server node_name
        return {chef_node: nil, chef_client: nil} if node_name.blank?
        {
          :chef_node => knife_instance.chef_node_delete(node_name),
          :chef_client => knife_instance.chef_client_delete(node_name)
        }
      end

      def delete_server
        mongo = ::Devops::Db.connector
        if @server.static?
          if !@server.chef_node_name.nil?
            unbootstrap
          end
          mongo.server_delete @server.id
          puts_and_flush "Static server '#{@server.id}' is removed"
          return 0
        end

        if @server.chef_node_name.present?
          puts_and_flush "Deleting from chef server:"
          delete_from_chef_server(@server.chef_node_name).each do |key, result|
            @out.puts "#{key} - #{result}"
          end
        else
          puts_and_flush "Chef node name is empty, skipping deleting from chef server."
        end

        puts_and_flush "Deleting from cloud:"
        provider = @server.provider_instance
        begin
          puts_and_flush provider.delete_server @server
        rescue Fog::Compute::OpenStack::NotFound, Fog::Compute::AWS::NotFound
          puts_and_flush "Server with id '#{@server.id}' not found among '#{provider.name}' servers"
        end
        mongo.server_delete @server.id
        puts_and_flush "Server '#{@server.id}' with name '#{@server.chef_node_name}' for project '#{@server.project}-#{@server.deploy_env}' is removed."
        0
      end

      def roll_back
        @out.puts "Trying to roll back..."
        unless @server.id.nil?
          @out.puts "Server '#{@server.chef_node_name}' with id '#{@server.id}' is not created"
          @out.puts delete_from_chef_server(@server.chef_node_name).values.join("\n")
          begin
            @out.puts @server.provider_instance.delete_server(@server)
          rescue => e
            @out.puts e.message
          end
          @out << "\nRolled back\n"
        end
      end

      def add_run_list_to_deploy_info out, deploy_info
        out << "\nGenerate run list hook...\n"
        if deploy_info["run_list"]
          out << "Deploy info already contains 'run_list': #{deploy_info["run_list"].join(", ")}\n"
          return
        end
        out << "Project run list: #{@project.run_list.join(", ")}\n"
        out << "Deploy environment run list: #{@deploy_env.run_list.join(", ")}\n"
        out << "Server run list: #{@server.run_list.join(", ")}\n"
        deploy_info["run_list"] = compute_run_list
        out << "New deploy run list: #{deploy_info["run_list"].join(", ")}\nRun list has been generated\n\n"
      end

      def compute_run_list
        rlist = []
        [@deploy_env.provider_instance.run_list, @project.run_list, @deploy_env.run_list, @server.run_list].each do |sub_run_list|
          rlist += sub_run_list if sub_run_list
        end
        if @server.stack
          stack = Devops::Db.connector.stack(@server.stack)
          srl = stack.run_list
          rlist += srl if srl
        end
        rlist.uniq
      end

      private

      def schedule_expiration
        if @deploy_env.expires
          job_id = ExpirationScheduler.new(@deploy_env.expires, @server).schedule_expiration!
          puts_and_flush "Planning expiration in #{@deploy_env.expires}, job_id: #{job_id}"
        end
      end

      def check_ssh_command(cert_path, address)
        cmd = 'ssh '
        cmd << "-i #{cert_path} "
        cmd << '-q '
        cmd << '-o StrictHostKeyChecking=no '
        cmd << '-o ConnectTimeout=2 -o ConnectionAttempts=1 '
        cmd << "#{address} 'exit'"
        cmd << " 2>&1"
        cmd
      end

      def execute_system_command(cmd)
        `#{cmd}`
      end

      def last_command_successful?
        $?.success?
      end

      def knife_instance
        @knife_instance ||= KnifeFactory.instance
      end

    end
  end
end