#!/usr/bin/ruby
# -*- encoding: binary -*-

unless RUBY_VERSION >= "1.9.2"
  raise LoadError, "OverSIP requires Ruby version >= 1.9.2 (current version is #{RUBY_VERSION})"
end

# First of all, trap some signals in order to ignore them if they arrive while
# loading server libraries.
[:HUP, :INT, :USR1, :USR2].each {|signal| trap(signal) {} }

require "optparse"
require "etc"
require "oversip"


module OverSIP

  class Executable

    @log_id = "executable"

    def self.run
      ::OverSIP::Logger.load_methods
      extend ::OverSIP::Logger

      # Options by default.
      options = {
        :num_instances => 1,
        :colorize => true
      }

      OptionParser.new("", 28, "  ") do |opts|
        opts.banner = "#{::OverSIP::DESCRIPTION}" \
                      "\n\nUsage: #{File.basename(__FILE__)} " \
                      "[#{::OverSIP::PROGRAM_NAME} options] [Ruby options]"

        opts.separator "\n#{::OverSIP::PROGRAM_NAME} options:"

        opts.on("-P", "--pid FILE", "Create a PID file (required)") do |value|
          options[:pid_file] = value
        end

        opts.on("-p", "--process-name NAME", "Change the running process name, also affects to syslogger process and Posix Message Queue name (default 'oversip')") do |value|
          options[:process_name] = value
        end

        opts.on("--config-dir DIR", "Absolute path to the directory with user configuration files (default '/etc/oversip/')") do |value|
          options[:config_dir] = value
        end

        opts.on("--config-file FILE", "Name of the configuration file within the configuration directory (default 'oversip.conf')") do |value|
          options[:config_file] = value
        end

        opts.on("-u", "--user USER", "System user to run with") do |value|
          options[:user] = value
        end

        opts.on("-g", "--group GROUP", "System group to run with") do |value|
          options[:group] = value
        end

        opts.on("-n", "--num-instances NUM", "Number of OverSIP instances that will run together in this host (this parameter is just for some resources allocation, it does not run NUM instances!) (default 1)") do |value|
          options[:num_instances] = value.to_i
        end

        opts.on("--no-color", "Don't colorize text printed in stdout") do |value|
          options[:colorize] = false
        end

        opts.on("--remove-mqueue MQUEUE", "Destroy the Posix Message Queue with the given name and exit") do |value|
          require "posix_mq"

          begin
            POSIX_MQ.unlink value
          rescue ::Errno::ENOENT
          rescue ::Errno::EACCES => e
            fatal "cannot remove '#{value}' posix message queue due file permissions"
            exit 1
          rescue ::Errno::EINVAL => e
            fatal "cannot remove '#{value}' posix message queue, invalid name"
            exit 1
          ensure
            exit
          end
        end

        opts.separator "\nRuby options:"

        opts.on("-d", "--debug", "Set debugging flags ($DEBUG = true)") do
          $DEBUG = true
        end

        opts.on("-w", "--warn", "Turn warnings on ($-w = true)") do
          $-w = true
        end

        opts.on("-I", "--include PATH", "Add PATH to $LOAD_PATH (may be used more than once)") do |path|
          $LOAD_PATH.unshift(*path.split(/:/))
        end

        opts.on("-r", "--require LIBRARY", "Load LIBRARY before running the programm (may be used more than once)") do |library|
          require library
        end

        opts.separator "\nCommon options:"

        opts.on_tail("-h", "--help", "Show this message") do
          puts opts.to_s
          exit
        end

        opts.on_tail("-v", "--version", "Show version") do
          puts ::OverSIP::DESCRIPTION
          exit
        end

        begin
          opts.parse! ARGV
        rescue ::OptionParser::InvalidOption => e
          log_system_error e.message
          puts
          puts opts.to_s
          exit! 1
        rescue ::OptionParser::MissingArgument => e
          log_system_error e.message
          puts
          puts opts.to_s
          exit! 1
        end
      end

      log_system_info "#{::OverSIP::PROGRAM_NAME} #{::OverSIP::VERSION} starting..."

      # Options checks.

      # PID file is required.
      unless options[:pid_file]
        fatal "PID file is required (use -P or --pid option)"
      end

      # Ignore user/group if the launcher is not being running as root.
      unless Process.euid == 0
        log_system_warn "ignoring user/group parameters when not running as root"
        options.delete :user
        options.delete :group
      else
        # Get the uid and gid to run with.
        if options[:user]
          begin
            Etc.getpwnam options[:user]
          rescue ArgumentError
            fatal "user '#{options[:user]}' does not exist in the system"
          end
        end
        if options[:group]
          begin
            Etc.getgrnam options[:group]
          rescue ArgumentError
            fatal "group '#{options[:group]}' does not exist in the system"
          end
        end
      end

      # Check the --num-instances parameter.
      if options[:num_instances] < 1
        fatal "num_instances #{n} is not a valid value (must be greater than 0)"
      end

      # Set the command name (as it appears in "ps" output) to given --process_name option (-p)
      # or to the script filename otherwise.
      $0 = options[:process_name] || File.basename(__FILE__)

      OverSIP.master_name = $0
      log_system_info "master process name: #{OverSIP.master_name}"

      OverSIP::Config.load options[:config_dir], options[:config_file]
      log_system_info "applied configuration:"
      OverSIP::Config.print options[:colorize]

      log_system_info "creating Posix Message Queue for communicating master and syslogger processes"
      OverSIP::Logger.init_logger_mq options[:num_instances], options[:group]
      OverSIP::Logger.load_methods

      OverSIP::Launcher.daemonize!(options)
      OverSIP::Launcher.run(options)

    end  # def run
  end  # class Executable
end  # module OverSIP


::OverSIP::Executable.run