module Justprep

# File lib/justprep.rb, line 127
def execute
  handle_command_line_parameters

  mainfile  = just_find_it

  if mainfile.nil?
    STDERR.puts "WARNING: JUSTPREP_FILENAME_IN Not Found: #{JUSTPREP_FILENAME_IN}"
    exit(0)
  end

  basefile  = mainfile.parent + JUSTPREP_FILENAME_OUT

  text = mainfile.readlines.map{|x| x.chomp} # drop the line ending from each line

  modules = find_modules text

  if modules.empty?
    basefile.write text
    exit(0)
  end

  modules.each do |a_line|
    an_index        = text.index a_line
    begin_filename  = a_line.index(' ')

    if begin_filename.nil?
      module_filename = ""
    else
      module_filename = a_line[begin_filename, a_line.size - begin_filename].chomp.strip
    end

    if module_filename.empty?
      STDERR.puts "ERROR: No path/to/file was provided"
      line_out = sprintf('% d ', an_index+1)
      STDERR.puts (" "*line_out.size)+"|"
      STDERR.puts "#{line_out}| #{a_line}"
      STDERR.print (" "*line_out.size)+"|"
      STDERR.puts (" "*(a_line.size+2)) + "^"
      exit(1)
    end

    if module_filename.include?('~')  || module_filename.include?('$')
      module_filename = expand_file_path(module_filename)
    end

    module_path     = Pathname.new(module_filename)

    if module_path.relative?
      module_path = mainfile.parent + module_path
    end

    if module_path.exist?
      text[an_index]  = include_content_from(module_path)
    else
      STDERR.puts "ERROR: File Does Not Exist - #{module_path}"
      line_out = sprintf('% d ', an_index+1)
      STDERR.puts (" "*line_out.size)+"|"
      STDERR.puts "#{line_out}| #{a_line}"
      STDERR.print (" "*line_out.size)+"|"
      STDERR.puts (" "*(a_line.index(module_filename)+1)) + "^"
      exit(1)
    end
  end # modules.each do |a_line|

  basefile.write text.flatten!.join "\n"
end

# File lib/justprep.rb, line 61
def expand_file_path(a_path_string)
  if a_path_string.start_with? '~'
    a_path_string = "${HOME}" + a_path_string[1, a_path_string.size-1]
  end

  a_path_string = `echo "#{a_path_string}"`.chomp

  return a_path_string
end

# File lib/justprep.rb, line 29
def find_modules(text)
  modules = []

  JUSTPREP_KEYWORDS.each do |keyword|
    modules << text.select{|x| x.start_with?("#{keyword} ") || x.strip == keyword}
  end

  return modules.flatten!
end

# File lib/justprep.rb, line 110
def handle_command_line_parameters
  if ARGV.size > 0
    ARGV.each do |param|
      if "--version" == param
        puts "jusrprep v#{VERSION} (ruby)"
      elsif ["-h", "--help"].include?(param)
        usage
      else
        STDERR.puts "justprep does not support: #{param}"
        exit(1)
      end
    end
  end
end

# File lib/justprep.rb, line 41
def include_content_from(file_path)
  content   = []
  content  << "\n# >>> #{file_path}"
  content  << file_path.readlines.map{|x| x.chomp} # TODO: support recursion??
  content  << "# <<< #{file_path}\n"

  return content.flatten
end

# File lib/justprep.rb, line 52
def just_find_it(here=Pathname.pwd)
  mainfile = here + JUSTPREP_FILENAME_IN
  return mainfile if mainfile.exist?
  return nil if here == here.parent
  return just_find_it(here.parent)
end

# File lib/justprep.rb, line 72
    def usage
      puts <<~EOS
        justprep v#{VERSION} (ruby)
        A pre-processor to the just command line utility
        By Dewayne VanHoozer <dvanhoozer@gmail.com>

        USAGE:
          justprep [flags] && just

        FLAGS:
              --version   Shows the current version
          -h, --help      Displays this usage message

        DESCRIPTION:
          Looks for a file named #{JUSTPREP_FILENAME_IN} in the current
          directory hierarchy.  If found it replaces all lines that
          have the keywords (#{JUSTPREP_KEYWORDS.join(", ")}) followed
          by file path with the contents of the specified file.

        SYSTEM ENVIRONMENT VARIABLES:
                                    Default Value
          JUSTPREP_FILENAME_IN .... main.just
          JUSTPREP_FILENAME_OUT ... justfile
          JUSTPREP_KEYWORDS ....... 'import include require with'

        SUGGESTION:
          Create an alias for your command shell. For example
            alias jj='justprop && just'

        THANKS TO:
          Casey Rodarmor <casey@rodarmor.com>
          Just because just is just a handy utility with just an odd name. :)

      EOS
    end