require 'spec_helper'

describe Lumberjack::Device::Writer do

  let(:time_string){ "2011-01-15T14:23:45.123" }
  let(:time){ Time.parse(time_string) }
  let(:stream){ StringIO.new }
  let(:entry){ Lumberjack::LogEntry.new(time, Lumberjack::Severity::INFO, "test message", "app", 12345, "ABCD") }
  
  it "should buffer output and not write directly to the stream" do
    device = Lumberjack::Device::Writer.new(stream, :template => ":message")
    device.write(entry)
    stream.string.should == ""
    device.flush
    stream.string.should == "test message#{Lumberjack::LINE_SEPARATOR}"
  end
    
  it "should flush the buffer when it gets to the specified size" do
    device = Lumberjack::Device::Writer.new(stream, :buffer_size => 15, :template => ":message")
    device.write(entry)
    stream.string.should == ""
    device.write(entry)
    stream.string.should == "test message#{Lumberjack::LINE_SEPARATOR}test message#{Lumberjack::LINE_SEPARATOR}"
  end
  
  it "should sync the stream and flush it when the device is flushed" do
    # Create an IO like object that require flush to be called
    io = Object.new
    def io.init; @string = ""; @buffer = ""; @sync = false; end
    def io.write(string); @buffer << string; end
    def io.flush; @string << @buffer; @buffer = ""; end
    def io.string; @string; end
    def io.sync=(val); @sync = val; end
    def io.sync; @sync; end
    io.init
    
    device = Lumberjack::Device::Writer.new(io, :template => ":message")
    device.write(entry)
    io.string.should == ""
    device.flush
    io.string.should == "test message#{Lumberjack::LINE_SEPARATOR}"
    io.sync.should == true
  end
  
  it "should be able to set the buffer size" do
    device = Lumberjack::Device::Writer.new(stream, :buffer_size => 15)
    device.buffer_size.should == 15
    device.buffer_size = 100
    device.buffer_size.should == 100
  end
  
  it "should have a default buffer size of 32K" do
    device = Lumberjack::Device::Writer.new(stream)
    device.buffer_size.should == 32768
  end
  
  it "should write entries out to the stream with a default template" do
    device = Lumberjack::Device::Writer.new(stream)
    device.write(entry)
    device.flush
    stream.string.should == "[2011-01-15T14:23:45.123 INFO app(12345) #ABCD] test message#{Lumberjack::LINE_SEPARATOR}"
  end
  
  it "should write entries out to the stream with a custom template" do
    device = Lumberjack::Device::Writer.new(stream, :template => ":message")
    device.write(entry)
    device.flush
    stream.string.should == "test message#{Lumberjack::LINE_SEPARATOR}"
  end
  
  it "should be able to specify the time format for the template" do
    device = Lumberjack::Device::Writer.new(stream, :time_format => :microseconds)
    device.write(entry)
    device.flush
    stream.string.should == "[2011-01-15T14:23:45.123000 INFO app(12345) #ABCD] test message#{Lumberjack::LINE_SEPARATOR}"
  end
  
  it "should be able to specify a block template for log entries" do
    device = Lumberjack::Device::Writer.new(stream, :template => lambda{|e| e.message.upcase})
    device.write(entry)
    device.flush
    stream.string.should == "TEST MESSAGE#{Lumberjack::LINE_SEPARATOR}"
  end
  
  it "should write to STDERR if an error is raised when flushing to the stream" do
    stderr = $stderr
    $stderr = StringIO.new
    begin
      device = Lumberjack::Device::Writer.new(stream, :template => ":message")
      stream.should_receive(:write).and_raise(StandardError.new("Cannot write to stream"))
      device.write(entry)
      device.flush
      $stderr.string.should include("test message#{Lumberjack::LINE_SEPARATOR}")
      $stderr.string.should include("StandardError: Cannot write to stream")
    ensure
      $stderr = stderr
    end
  end
  
  context "multi line messages" do
    let(:message){ "line 1#{Lumberjack::LINE_SEPARATOR}line 2#{Lumberjack::LINE_SEPARATOR}line 3" }
    let(:entry){ Lumberjack::LogEntry.new(time, Lumberjack::Severity::INFO, message, "app", 12345, "ABCD") }
    
    it "should have a default template for multiline messages" do
      device = Lumberjack::Device::Writer.new(stream)
      device.write(entry)
      device.flush
      stream.string.split(Lumberjack::LINE_SEPARATOR).should == ["[2011-01-15T14:23:45.123 INFO app(12345) #ABCD] line 1", "> [#ABCD] line 2", "> [#ABCD] line 3"]
    end
  
    it "should be able to specify a template for multiple line messages" do
      device = Lumberjack::Device::Writer.new(stream, :additional_lines => " // :message")
      device.write(entry)
      device.flush
      stream.string.should == "[2011-01-15T14:23:45.123 INFO app(12345) #ABCD] line 1 // line 2 // line 3#{Lumberjack::LINE_SEPARATOR}"
    end
  end
end