#!/usr/bin/env ruby

require 'rake'
require 'rake/tasklib'

module Micronaut

  class RakeTask < ::Rake::TaskLib

    # Name of task. (default is :examples)
    attr_accessor :name

    # If true, requests that the specs be run with the warning flag set.
    # E.g. warning=true implies "ruby -w" used to run the specs. Defaults to false.
    attr_accessor :warning

    # Glob pattern to match example files. (default is 'examples/**/*_example.rb')
    attr_accessor :pattern

    # Array of commandline options to pass to ruby. Defaults to [].
    attr_accessor :ruby_opts

    # Whether or not to fail Rake when an error occurs (typically when examples fail).
    # Defaults to true.
    attr_accessor :fail_on_error

    # A message to print to stderr when there are failures.
    attr_accessor :failure_message

    # Use verbose output. If this is set to true, the task will print
    # the executed spec command to stdout. Defaults to false.
    attr_accessor :verbose

    # Use rcov for code coverage? defaults to false
    attr_accessor :rcov
    
    # The options to pass to rcov.  Defaults to blank
    attr_accessor :rcov_opts

    def initialize(*args)
      @name = args.shift || :examples
      @pattern, @rcov_opts = nil, nil
      @warning, @rcov = false, false
      @ruby_opts = []
      @fail_on_error = true

      yield self if block_given?
      @pattern ||= 'examples/**/*_example.rb'
      define
    end

    def define # :nodoc:
      actual_name = Hash === name ? name.keys.first : name
      desc("Run all examples") unless ::Rake.application.last_comment

      task name do
        RakeFileUtils.send(:verbose, verbose) do
          if examples_to_run.empty?
            puts "No examples matching #{pattern} could be found"
          else
            cmd_parts = [rcov ? 'rcov' : RUBY]
            cmd_parts += rcov ? [rcov_opts] : ruby_opts
            cmd_parts << "-w" if warning
            cmd_parts += examples_to_run.collect { |fn| %["#{fn}"] }
            cmd = cmd_parts.join(" ")
            puts cmd if verbose
            unless system(cmd)
              STDERR.puts failure_message if failure_message
              raise("Command #{cmd} failed") if fail_on_error
            end
          end
        end
      end

      self
    end

    def examples_to_run # :nodoc:
      FileList[ pattern ].to_a
    end

  end

end