#!/usr/bin/env ruby
$LOAD_PATH.unshift File.expand_path('../../lib', __FILE__)
require 'quickl'
require 'erb'

#
# Quickl - Generate Ruby command line apps quickly
#
# SYNOPSIS
#   #{program_name} [options] COMMAND_NAME
#
# OPTIONS
# #{summarized_options}
#
# DESCRIPTION
#   This tool helps you generating Ruby command line applications
#
class Quickl::Main < Quickl::Command(__FILE__, __LINE__)
  include Quickl::Naming
  
  OPTION_HELPERS = {
    :version => %q{
      opt.on_tail('--version', 'Show version and exit'){
        raise Quickl::Exit, "#{Quickl.program_name} #{VERSION}"
      }
    },
    :help => %q{
      opt.on_tail('--help', "Show this help message"){ 
        raise Quickl::Help 
      }
    }
  }
  
  # Name of the command to generate
  attr_reader :cmd_name
  
  # Generate require header
  attr_reader :header
  
  # Generate require footer
  attr_reader :footer
  
  # Creates a command instance
  def initialize
    @layout = :single
    @gen_options = [:help, :version]
  end
  
  # Install options
  options do |opt|
    
    opt.on("--layout=LAYOUT", [:single, :delegator], 
           "Select specific command layout (single,delegator)") do |l|
      @layout = l
    end
    
    opt.on('--options x,y,z', Array,
           "Automatically generate options for... (#{OPTION_HELPERS.keys.join(', ')})") do |list|
      @gen_options = list.collect{|s| s.to_sym}
      unless (unknown = @gen_options.reject{|s| OPTION_HELPERS.has_key?(s)}).empty?
        raise Quickl::InvalidOption, "Unknown option helpers: #{unknown.join(',')}"
      end
    end

    @header = true
    opt.on('--[no-]header',
           "Generate header (require rubygems + quickl)"){|value|
      @header = value
    }
    
    @footer = true
    opt.on('--[no-]footer',
           "Generate footer (command execution)"){|value|
      @footer = value
    }
    
    # Show the help and exit
    opt.on_tail("--help", "Show help") do
      raise Quickl::Help
    end

    # Show version and exit
    opt.on_tail("--version", "Show version") do
      raise Quickl::Exit, "#{Quickl.program_name} #{Quickl::VERSION} #{Quickl::COPYRIGHT}"
    end
    
  end
  
  # Loads template to use
  def template
    @template ||= File.expand_path("../../templates/#{@layout}.erb", __FILE__)
  end

  # Execute the command
  def execute(args)
    if args.size == 1
      @cmd_name = args.shift
      erb = ERB.new(File.read(template))
      $stdout.puts erb.result(binding)
    else
      raise Quickl::InvalidArgument, "Invalid arguments: #{args.join(' ')}"
    end
  end

  ### ERB scoping

  # Class name of the command to generate
  def cmd_class_name
    command2module(cmd_name)
  end
  
  def indent(str, offset)
    if offset >= 0
      str.gsub(/^/, ' ' * offset)
    else
      str.gsub(/^ {0,#{-offset}}/, "")
    end
  end
      
  def tabto(str, offset)
    if str =~ /^( *)\S/
      indent(str, offset - $1.length)
    else
      str
    end
  end

  # Returns option helpers to include
  def option_helpers
    @gen_options.collect{|s| tabto(OPTION_HELPERS[s], 0).strip}
  end
  
end # class Quickl::Command::Main
Quickl::Main.run(ARGV, __FILE__)