require 'puppet-debugger/input_responder_plugin'
require 'table_print'

module PuppetDebugger
  module InputResponders
    class Functions < InputResponderPlugin
      COMMAND_WORDS = %w(functions)
      SUMMARY = 'List all the functions available in the environment.'
      COMMAND_GROUP = :environment
      FUNC_NATIVE_NAME_REGEX = %r{\Afunction\s([\w\:]+)}
      FUNC_V4_NAME_REGEX = %r{Puppet\:\:Functions.create_function\s?\(?\:?\'?([\w\:]+)}

      def run(args = [])
        filter = args.first || ''
        TablePrint::Printer.table_print(sorted_list(filter), [:full_name, :mod_name])
      end

      def sorted_list(filter = '')
        search = /#{Regexp.escape(filter)}/
        function_map.values.find_all do | v| 
          "#{v[:mod_name]}_#{v[:full_name]}" =~ search
        end.sort {|a,b| a[:full_name] <=> b[:full_name]}
      end

      # append a () to functions so we know they are functions
      def func_list
        # ideally we should get a list of function names via the puppet loader    
        function_map.map { |name, metadata| "#{metadata[:full_name]}()" }
      end

      # @return [Hash] - a map of all the functions
      def function_map
        functions = {}
        function_files.each do |file|
          obj = function_obj(file)
          # return the last matched in cases where rbenv might be involved
          functions[obj[:full_name]] = obj
        end
        functions
      end


      def lib_dirs(module_dirs = modules_paths)
        dirs = module_dirs.map do |mod_dir|
          Dir["#{mod_dir}/*/lib"].entries
        end.flatten
        dirs + [puppet_debugger_lib_dir]
      end


      # @return [Array] - returns a array of the parentname and function name
      def function_obj(file)
        namespace = nil
        name = nil
        if file =~ /\.pp/
          File.readlines(file, :encoding => 'UTF-8').find do |line|
            # TODO: not getting namespace for functio
            if line.match(FUNC_NATIVE_NAME_REGEX) 
              namespace, name = $1.split('::', 2) 
              name = namespace if name.nil?
              namespace = '' if namespace == name
            end
          end
        elsif file.include?('lib/puppet/functions')
          File.readlines(file, :encoding => 'UTF-8').find do |line|
            if line.match(FUNC_V4_NAME_REGEX) 
              namespace, name = $1.split('::', 2) 
              name = namespace if name.nil?
              namespace = '' if namespace == name
            end
          end
        end
        name ||= File.basename(file, File.extname(file)) 
        match = file.match('\/(?<mod>[\w\-\.]+)\/(lib|functions|manifests)')
        summary_match = File.read(file, :encoding => 'UTF-8').match(/@summary\s(.*)/)
        summary = summary_match[1] if summary_match

       # match = file.match('(?<mod>\w+)\/functions|manifests|lib')
        mod_name =  match[:mod] unless match.nil? 
        full_name = namespace.nil? || namespace.empty? ? name : name.prepend("#{namespace}::")
        {namespace: namespace, summary: summary, mod_name: mod_name, name: name, full_name: full_name, file: file}
      end

      private

      # load all the lib dirs so puppet can find the functions
      # at this time, this function is not being used
      def load_lib_dirs(module_dirs = modules_paths)
        lib_dirs(module_dirs).each do |lib|
          $LOAD_PATH << lib
        end
      end

      # returns a array of function files which is only required
      # when displaying the function map, puppet will load each function on demand
      # in the future we may want to utilize the puppet loaders to find these things
      def function_files
        search_dirs = lib_dirs.map do |lib_dir|
          [File.join(lib_dir, 'puppet', 'functions', '**', '*.rb'),
           File.join(lib_dir, 'functions', '**', '*.rb'),
           File.join(File.dirname(lib_dir), 'functions', '**', '*.pp'),
           File.join(lib_dir, 'puppet', 'parser', 'functions', '*.rb')]
        end

        # add puppet lib directories
        search_dirs << [File.join(puppet_lib_dir, 'puppet', 'functions', '**', '*.rb'),
                        File.join(puppet_lib_dir, 'puppet', 'parser', 'functions', '*.rb')]
        Dir.glob(search_dirs.flatten)
      end


    end
  end
end