module Exctl
  class CLI
    def initialize(argv)
      @args = argv.clone
      @cmd = (@args.shift || 'help').strip.downcase
      @cmd = 'help'    if [nil,'-h','--help','h'].include?(@cmd)
      @cmd = 'version' if [nil,'-v','--version','v'].include?(@cmd)
      @cmd = ('cmd_' + @cmd.gsub(/^-+/,'').gsub('-','_')).to_sym
      @opts = {}
    end

    def run!()
      if self.respond_to?(@cmd) then self.send @cmd
      else
        $stderr.puts "ERROR: Command '#{@cmd}' not implemented."
        $stderr.puts "USAGE: exctl (#{avail_cmds.join('|')}) [OPTIONS]"
        exit 1
      end
    end

    def avail_cmds; @avail_cmds ||= (self.methods-Object.methods).map(&:to_s).select{|m|m[0..3]=='cmd_'}.map{|m|m[4..-1]} end
    def cmd_version; puts Exctl.version end

    def doc_help; 'Output this help.' end
    def cmd_help
      puts "exctl - Execution control; project command-line generator."
      puts "        v#{Exctl.version}\n\n"
      puts "USAGE: exctl (#{avail_cmds.join('|')}) [OPTIONS]\n\n"
      puts avail_cmds.map{|c| hc='doc_'+c; respond_to?(hc) ? '   ' + c.ljust(10) + ':  ' + send(hc) : nil}.compact.join("\n") + "\n\n"
    end

    def doc_init; 'BIN-NAME [DIR=.] - Creates/updates main ctl script and support files in the given DIR.' end
    def cmd_init
      require 'erb'
      binname = @args.shift
      dir     = @args.shift || '.'
      if binname.nil?
        $stderr.puts "ERROR: project/binary name not specified."
        $stderr.puts "USAGE: exctl init BIN-NAME [DIR=.]"
        exit 3
      end

      b = binding

      libdest = Path["./.exctl"]
      $stderr.puts "  create dir:  #{libdest}/"
      libdest.dir!

      LIB_DIR['**/**',false].each do |f|
        relative = f.short(LIB_DIR)
        unless relative.to_s[0..0]=='.' || relative.to_s == 'exctl/cli.rb'
          dest = libdest ** relative
          if f.dir?
            $stderr.puts "  create dir:  #{dest}/"
            dest.dir!
          else
            $stderr.puts "  create file: #{dest}"
            system "cp", f, dest
          end
        end
      end

      $stderr.puts "  create file: #{binname}"
      dispatch_wrapper = ERB.new(File.read(TEMPLATE_DIR ** 'dispatch-wrapper.erb')).result(b)
      File.write(binname, dispatch_wrapper)
      $stderr.puts "  chmod  file: #{binname}"
      File.chmod(0774, binname)
    end
  end
end