require 'readline'

module Qcmd
  module InputCompleter
    # the commands listed here should represent every possible legal command
    ReservedWords = %w[
      connect exit quit workspace workspaces disconnect
    ]

    ReservedWorkspaceWords = %w[
      cueLists selectedCues runningCues runningOrPausedCues thump
      go stop pause resume reset panic disconnect
    ]

    ReservedCueWords = %w[
      cue stop pause resume load preview reset panic loadAt uniqueID
      hasFileTargets hasCueTargets allowsEditingDuration isLoaded isRunning
      isPaused isBroken preWaitElapsed actionElapsed postWaitElapsed
      percentPreWaitElapsed percentActionElapsed percentPostWaitElapsed
      type number name notes cueTargetNumber cueTargetId preWait duration
      postWait continueMode flagged armed colorName basics children
      sliderLevel sliderLevels
    ]

    CompletionProc = Proc.new {|input|
      # puts "input: #{ input }"

      matcher  = /^#{Regexp.escape(input)}/
      commands = ReservedWords.grep(matcher)

      if Qcmd.connected?
        # have selected a machine
        if Qcmd.context.workspace_connected?
          # have selected a workspace
          cue_numbers = Qcmd.context.workspace.cues.map(&:number)
          commands    = commands +
                        cue_numbers.grep(matcher) +
                        ReservedCueWords.grep(matcher) +
                        ReservedWorkspaceWords.grep(matcher)
        else
          # haven't selected a workspace yet
          names           = Qcmd.context.machine.workspace_names
          quoted_names    = names.map {|wn| %["#{wn}"]}
          workspace_names = (names + quoted_names).grep(matcher)
          workspace_names = quote_if_necessary workspace_names
          commands = commands + workspace_names
        end
      else
        # haven't selected a machine yet
        machine_names = Qcmd::Network.names
        quoted_names = machine_names.map {|mn| %["#{mn}"]}
        names = (quoted_names + machine_names).grep(matcher)
        names = quote_if_necessary(names)
        # unquote
        commands = commands + names
      end

      commands
    }

    class << self
      # if the name of a thing has a space in it, it must be surrounded by double
      # quotes to be properly handled by the parser. so before we pass back
      # unquoted space-containing results, we must quote them.
      def quote_if_necessary names
        names.map do |name|
          if / / =~ name && /"/ !~ name
            # if name has a space and is not already quoted
            %["#{ name }"]
          else
            name
          end
        end
      end
    end
  end
end

if Readline.respond_to?("basic_word_break_characters=")
  Readline.basic_word_break_characters= " \t\n`><=;|&{("
end
Readline.completion_append_character = nil
Readline.completion_case_fold = true
Readline.completion_proc = Qcmd::InputCompleter::CompletionProc