class Journey::GTG::TransitionTable

# File lib/journey/gtg/transition_table.rb, line 10
def initialize
  @regexp_states = Hash.new { |h,k| h[k] = {} }
  @string_states = Hash.new { |h,k| h[k] = {} }
  @accepting     = {}
  @memos         = Hash.new { |h,k| h[k] = [] }
end

# File lib/journey/gtg/transition_table.rb, line 112
def []= from, to, sym
  case sym
  when String
    @string_states[from][sym] = to
  when Regexp
    @regexp_states[from][sym] = to
  else
    raise ArgumentError, 'unknown symbol: %s' % sym.class
  end
end

# File lib/journey/gtg/transition_table.rb, line 25
def accepting? state
  @accepting[state]
end

# File lib/journey/gtg/transition_table.rb, line 21
def accepting_states
  @accepting.keys
end

# File lib/journey/gtg/transition_table.rb, line 17
def add_accepting state
  @accepting[state] = true
end

# File lib/journey/gtg/transition_table.rb, line 29
def add_memo idx, memo
  @memos[idx] << memo
end

# File lib/journey/gtg/transition_table.rb, line 37
def eclosure t
  Array(t)
end

# File lib/journey/gtg/transition_table.rb, line 33
def memo idx
  @memos[idx]
end

# File lib/journey/gtg/transition_table.rb, line 41
def move t, a
  move_string(t, a).concat move_regexp(t, a)
end

# File lib/journey/gtg/transition_table.rb, line 123
def states
  ss = @string_states.keys + @string_states.values.map(&:values).flatten
  rs = @regexp_states.keys + @regexp_states.values.map(&:values).flatten
  (ss + rs).uniq
end

# File lib/journey/gtg/transition_table.rb, line 45
def to_json
  require 'json'

  simple_regexp = Hash.new { |h,k| h[k] = {} }

  @regexp_states.each do |from, hash|
    hash.each do |re, to|
      simple_regexp[from][re.source] = to
    end
  end

  JSON.dump({
    :regexp_states => simple_regexp,
    :string_states => @string_states,
    :accepting     => @accepting
  })
end

# File lib/journey/gtg/transition_table.rb, line 63
def to_svg
  svg = IO.popen("dot -Tsvg", 'w+') { |f|
    f.write to_dot
    f.close_write
    f.readlines
  }
  3.times { svg.shift }
  svg.join.sub(/width="[^"]*"/, '').sub(/height="[^"]*"/, '')
end

# File lib/journey/gtg/transition_table.rb, line 129
def transitions
  @string_states.map { |from, hash|
    hash.map { |s, to| [from, s, to] }
  }.flatten(1) + @regexp_states.map { |from, hash|
    hash.map { |s, to| [from, s, to] }
  }.flatten(1)
end

# File lib/journey/gtg/transition_table.rb, line 73
def visualizer paths, title = 'FSM'
  viz_dir   = File.join File.dirname(__FILE__), '..', 'visualizer'
  fsm_js    = File.read File.join(viz_dir, 'fsm.js')
  fsm_css   = File.read File.join(viz_dir, 'fsm.css')
  erb       = File.read File.join(viz_dir, 'index.html.erb')
  states    = "function tt() { return #{to_json}; }"

  fun_routes = paths.shuffle.first(3).map do |ast|
    ast.map { |n|
      case n
      when Nodes::Symbol
        case n.left
        when ':id' then rand(100).to_s
        when ':format' then %w{ xml json }.shuffle.first
        else
          'omg'
        end
      when Nodes::Terminal then n.symbol
      else
        nil
      end
    }.compact.join
  end

  stylesheets = [fsm_css]
  svg         = to_svg
  javascripts = [states, fsm_js]

  # Annoying hack for 1.9 warnings
  fun_routes  = fun_routes
  stylesheets = stylesheets
  svg         = svg
  javascripts = javascripts

  require 'erb'
  template = ERB.new erb
  template.result(binding)
end