class Redis::Client

def _parse_driver(driver)
  driver = driver.to_s if driver.is_a?(Symbol)
  if driver.kind_of?(String)
    begin
      require_relative "connection/#{driver}"
    rescue LoadError, NameError => e
      begin
        require "connection/#{driver}"
      rescue LoadError, NameError => e
        raise RuntimeError, "Cannot load driver #{driver.inspect}: #{e.message}"
      end
    end
    driver = Connection.const_get(driver.capitalize)
  end
  driver
end

def _parse_options(options)
  return options if options[:_parsed]
  defaults = DEFAULTS.dup
  options = options.dup
  defaults.keys.each do |key|
    # Fill in defaults if needed
    if defaults[key].respond_to?(:call)
      defaults[key] = defaults[key].call
    end
    # Symbolize only keys that are needed
    options[key] = options[key.to_s] if options.has_key?(key.to_s)
  end
  url = options[:url] || defaults[:url]
  # Override defaults from URL if given
  if url
    require "uri"
    uri = URI(url)
    if uri.scheme == "unix"
      defaults[:path]   = uri.path
    elsif uri.scheme == "redis" || uri.scheme == "rediss"
      defaults[:scheme]   = uri.scheme
      defaults[:host]     = uri.host if uri.host
      defaults[:port]     = uri.port if uri.port
      defaults[:password] = CGI.unescape(uri.password) if uri.password
      defaults[:db]       = uri.path[1..-1].to_i if uri.path
      defaults[:role] = :master
    else
      raise ArgumentError, "invalid uri scheme '#{uri.scheme}'"
    end
    defaults[:ssl] = true if uri.scheme == "rediss"
  end
  # Use default when option is not specified or nil
  defaults.keys.each do |key|
    options[key] = defaults[key] if options[key].nil?
  end
  if options[:path]
    # Unix socket
    options[:scheme] = "unix"
    options.delete(:host)
    options.delete(:port)
  else
    # TCP socket
    options[:host] = options[:host].to_s
    options[:port] = options[:port].to_i
  end
  if options.has_key?(:timeout)
    options[:connect_timeout] ||= options[:timeout]
    options[:read_timeout]    ||= options[:timeout]
    options[:write_timeout]   ||= options[:timeout]
  end
  options[:connect_timeout] = Float(options[:connect_timeout])
  options[:read_timeout]    = Float(options[:read_timeout])
  options[:write_timeout]   = Float(options[:write_timeout])
  options[:reconnect_attempts] = options[:reconnect_attempts].to_i
  options[:db] = options[:db].to_i
  options[:driver] = _parse_driver(options[:driver]) || Connection.drivers.last
  case options[:tcp_keepalive]
  when Hash
    [:time, :intvl, :probes].each do |key|
      unless options[:tcp_keepalive][key].is_a?(Integer)
        raise "Expected the #{key.inspect} key in :tcp_keepalive to be an Integer"
      end
    end
  when Integer
    if options[:tcp_keepalive] >= 60
      options[:tcp_keepalive] = {:time => options[:tcp_keepalive] - 20, :intvl => 10, :probes => 2}
    elsif options[:tcp_keepalive] >= 30
      options[:tcp_keepalive] = {:time => options[:tcp_keepalive] - 10, :intvl => 5, :probes => 2}
    elsif options[:tcp_keepalive] >= 5
      options[:tcp_keepalive] = {:time => options[:tcp_keepalive] - 2, :intvl => 2, :probes => 1}
    end
  end
  options[:_parsed] = true
  options
end

def call(command)
  reply = process([command]) { read }
  raise reply if reply.is_a?(CommandError)
  if block_given?
    yield reply
  else
    reply
  end
end

def call_loop(command, timeout = 0)
  error = nil
  result = with_socket_timeout(timeout) do
    process([command]) do
      loop do
        reply = read
        if reply.is_a?(CommandError)
          error = reply
          break
        else
          yield reply
        end
      end
    end
  end
  # Raise error when previous block broke out of the loop.
  raise error if error
  # Result is set to the value that the provided block used to break.
  result
end

def call_pipeline(pipeline)
  commands = pipeline.commands
  return [] if commands.empty?
  with_reconnect pipeline.with_reconnect? do
    begin
      pipeline.finish(call_pipelined(commands)).tap do
        self.db = pipeline.db if pipeline.db
      end
    rescue ConnectionError => e
      return nil if pipeline.shutdown?
      # Assume the pipeline was sent in one piece, but execution of
      # SHUTDOWN caused none of the replies for commands that were executed
      # prior to it from coming back around.
      raise e
    end
  end
end

def call_pipelined(commands)
  return [] if commands.empty?
  # The method #ensure_connected (called from #process) reconnects once on
  # I/O errors. To make an effort in making sure that commands are not
  # executed more than once, only allow reconnection before the first reply
  # has been read. When an error occurs after the first reply has been
  # read, retrying would re-execute the entire pipeline, thus re-issuing
  # already successfully executed commands. To circumvent this, don't retry
  # after the first reply has been read successfully.
  result = Array.new(commands.size)
  reconnect = @reconnect
  begin
    exception = nil
    process(commands) do
      result[0] = read
      @reconnect = false
      (commands.size - 1).times do |i|
        reply = read
        result[i + 1] = reply
        exception = reply if exception.nil? && reply.is_a?(CommandError)
      end
    end
    raise exception if exception
  ensure
    @reconnect = reconnect
  end
  result
end

def call_with_timeout(command, timeout, &blk)
  with_socket_timeout(timeout) do
    call(command, &blk)
  end
rescue ConnectionError
  retry
end

def call_without_timeout(command, &blk)
  call_with_timeout(command, 0, &blk)
end

def connect
  @pid = Process.pid
  # Don't try to reconnect when the connection is fresh
  with_reconnect(false) do
    establish_connection
    call [:auth, password] if password
    call [:select, db] if db != 0
    call [:client, :setname, @options[:id]] if @options[:id]
    @connector.check(self)
  end
  self
end

def connect_timeout
  @options[:connect_timeout]
end

def connected?
  !! (connection && connection.connected?)
end

def db
  @options[:db]
end

def db=(db)
  @options[:db] = db.to_i
end

def disconnect
  connection.disconnect if connected?
end

def driver
  @options[:driver]
end

def ensure_connected
  disconnect if @pending_reads > 0
  attempts = 0
  begin
    attempts += 1
    if connected?
      unless inherit_socket? || Process.pid == @pid
        raise InheritedError,
          "Tried to use a connection from a child process without reconnecting. " +
          "You need to reconnect to Redis after forking " +
          "or set :inherit_socket to true."
      end
    else
      connect
    end
    yield
  rescue BaseConnectionError
    disconnect
    if attempts <= @options[:reconnect_attempts] && @reconnect
      retry
    else
      raise
    end
  rescue Exception
    disconnect
    raise
  end
end

def establish_connection
  server = @connector.resolve.dup
  @options[:host] = server[:host]
  @options[:port] = Integer(server[:port]) if server.include?(:port)
  @connection = @options[:driver].connect(@options)
  @pending_reads = 0
rescue TimeoutError,
       SocketError,
       Errno::ECONNREFUSED,
       Errno::EHOSTDOWN,
       Errno::EHOSTUNREACH,
       Errno::ENETUNREACH,
       Errno::ENOENT,
       Errno::ETIMEDOUT
  raise CannotConnectError, "Error connecting to Redis on #{location} (#{$!.class})"
end

def host
  @options[:host]
end

def id
  @options[:id] || "redis://#{location}/#{db}"
end

def inherit_socket?
  @options[:inherit_socket]
end

def initialize(options = {})
  @options = _parse_options(options)
  @reconnect = true
  @logger = @options[:logger]
  @connection = nil
  @command_map = {}
  @pending_reads = 0
  @connector =
    if options.include?(:sentinels)
      Connector::Sentinel.new(@options)
    elsif options.include?(:connector) && options[:connector].respond_to?(:new)
      options.delete(:connector).new(@options)
    else
      Connector.new(@options)
    end
end

def io
  yield
rescue TimeoutError => e1
  # Add a message to the exception without destroying the original stack
  e2 = TimeoutError.new("Connection timed out")
  e2.set_backtrace(e1.backtrace)
  raise e2
rescue Errno::ECONNRESET, Errno::EPIPE, Errno::ECONNABORTED, Errno::EBADF, Errno::EINVAL => e
  raise ConnectionError, "Connection lost (%s)" % [e.class.name.split("::").last]
end

def location
  path || "#{host}:#{port}"
end

def logging(commands)
  return yield unless @logger && @logger.debug?
  begin
    commands.each do |name, *args|
      logged_args = args.map do |a|
        case
        when a.respond_to?(:inspect) then a.inspect
        when a.respond_to?(:to_s)    then a.to_s
        else
          # handle poorly-behaved descendants of BasicObject
          klass = a.instance_exec { (class << self; self end).superclass }
          "\#<#{klass}:#{a.__id__}>"
        end
      end
      @logger.debug("[Redis] command=#{name.to_s.upcase} args=#{logged_args.join(' ')}")
    end
    t1 = Time.now
    yield
  ensure
    @logger.debug("[Redis] call_time=%0.2f ms" % ((Time.now - t1) * 1000)) if t1
  end
end

def password
  @options[:password]
end

def path
  @options[:path]
end

def port
  @options[:port]
end

def process(commands)
  logging(commands) do
    ensure_connected do
      commands.each do |command|
        if command_map[command.first]
          command = command.dup
          command[0] = command_map[command.first]
        end
        write(command)
      end
      yield if block_given?
    end
  end
end

def read
  io do
    value = connection.read
    @pending_reads -= 1
    value
  end
end

def read_timeout
  @options[:read_timeout]
end

def reconnect
  disconnect
  connect
end

def scheme
  @options[:scheme]
end

def timeout
  @options[:read_timeout]
end

def with_reconnect(val=true)
  begin
    original, @reconnect = @reconnect, val
    yield
  ensure
    @reconnect = original
  end
end

def with_socket_timeout(timeout)
  connect unless connected?
  begin
    connection.timeout = timeout
    yield
  ensure
    connection.timeout = self.timeout if connected?
  end
end

def without_reconnect(&blk)
  with_reconnect(false, &blk)
end

def without_socket_timeout(&blk)
  with_socket_timeout(0, &blk)
end

def write(command)
  io do
    @pending_reads += 1
    connection.write(command)
  end
end