module Jkf
  module Parser
    # CSA Parser
    class Csa < Base
      protected

      # kifu : csa2 | csa1
      def parse_root
        @scanner << "\n" unless /\n|\r|,/.match?(@scanner.string[-1]) # FIXME
        s0 = parse_csa2
        s0 = parse_csa1 if s0 == :failed
        s0
      end

      # csa2 : version22 information? initialboard moves?
      def parse_csa2
        s0 = @scanner.pos
        if parse_version22 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s1 = parse_information
          s1 = nil if s1 == :failed
          s2 = parse_initial_board
          if s2 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            s3 = parse_moves
            s3 = nil if s3 == :failed
            @reported_pos = s0
            s0 = -> (info, ini, ms) do
              ret = { 'header' => info['header'], 'initial' => ini, 'moves' => ms }
              if info && info['players']
                ret['header']['先手'] = info['players'][0] if info['players'][0]
                ret['header']['後手'] = info['players'][1] if info['players'][1]
              end
              ret
            end.call(s1, s2, s3)
          end
        end
        s0
      end

      # version22 : comment* "V2.2" nl
      def parse_version22
        s0 = @scanner.pos
        s1 = parse_comments
        s2 = match_str('V2.2')
        if s2 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s3 = parse_nl
          if s3 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            s0 = [s1, s2, s3]
          end
        end
        s0
      end

      # information : players? headers
      def parse_information
        s0 = @scanner.pos
        s1 = parse_players
        s1 = nil if s1 == :failed
        s2 = parse_headers
        if s2 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          @reported_pos = s0
          s0 = { 'players' => s1, 'header' => s2 }
        end
        s0
      end

      # headers : header*
      def parse_headers
        s0 = @scanner.pos
        s1 = []
        s2 = parse_header
        while s2 != :failed
          s1 << s2
          s2 = parse_header
        end
        @reported_pos = s0
        -> (header) do
          ret = {}
          header.each do |data|
            ret[normalize_header_key(data['k'])] = data['v']
          end
          ret
        end.call(s1)
      end

      # header : comment* "$" [^:]+ ":" nonls nl
      def parse_header
        s0 = @scanner.pos
        parse_comments
        if match_str('$') == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s4 = match_regexp(/[^:]/)
          if s4 == :failed
            s3 = :failed
          else
            s3 = []
            while s4 != :failed
              s3 << s4
              s4 = match_regexp(/[^:]/)
            end
          end
          if s3 == :failed
            @scanner.pos = s0
            s0 = :failed
          elsif match_str(':') != :failed
            s4 = parse_nonls
            if parse_nl == :failed
              @scanner.pos = s0
              s0 = :failed
            else
              @reported_pos = s0
              s0 = { 'k' => s3.join, 'v' => s4.join }
            end
          else
            @scanner.pos = s0
            s0 = :failed
          end
        end
        s0
      end

      # csa1 : players? initialboard? moves
      def parse_csa1
        s0 = @scanner.pos
        s1 = parse_players
        s1 = nil if s1 == :failed
        s2 = parse_initial_board
        s2 = nil if s2 == :failed
        s3 = parse_moves
        if s3 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          @reported_pos = s0
          s0 = -> (ply, ini, ms) do
            ret = { 'header' => {}, 'initial' => ini, 'moves' => ms }
            if ply
              ret['header']['先手'] = ply[0] if ply[0]
              ret['header']['後手'] = ply[1] if ply[1]
            end
            ret
          end.call(s1, s2, s3)
        end
        s0
      end

      # players : comment* ("N+" nonls nl)? comment* ("N-" nonls nl)?
      def parse_players
        s0 = @scanner.pos
        parse_comments
        s2 = @scanner.pos
        if match_str('N+') == :failed
          @scanner.pos = s2
          s2 = :failed
        else
          s4 = parse_nonls
          if parse_nl == :failed
            @scanner.pos = s2
            s2 = :failed
          else
            @reported_pos = s2
            s2 = s4
          end
        end
        s2 = nil if s2 == :failed
        parse_comments
        s4 = @scanner.pos
        if match_str('N-') == :failed
          @scanner.pos = s4
          s4 = :failed
        else
          s6 = parse_nonls
          if parse_nl == :failed
            @scanner.pos = s4
            s4 = :failed
          else
            @reported_pos = s4
            s4 = s6
          end
        end
        s4 = nil if s4 == :failed
        @reported_pos = s0
        [s2&.join, s4&.join]
      end

      # initialboard : comment* (hirate | ikkatsu | "") komabetsu comment* teban nl
      def parse_initial_board
        s0 = @scanner.pos
        parse_comments
        s2 = parse_hirate
        if s2 == :failed
          s2 = parse_ikkatsu
          if s2 == :failed
            s2 = @scanner.pos
            s3 = match_str('')
            if s3 != :failed
              @reported_pos = s2
              s3 = 'NO'
            end
            s2 = s3
          end
        end
        if s2 == :failed
          @scanner.pos = s0
          :failed
        else
          s3 = parse_komabetsu
          if s3 == :failed
            @scanner.pos = s0
            :failed
          else
            parse_comments
            s5 = parse_teban
            if s5 == :failed
              @scanner.pos = s0
              :failed
            elsif parse_nl != :failed
              @reported_pos = s0
              -> (data, koma, teban) do
                if data == 'NO'
                  data = koma
                else
                  data['data']['hands'] = koma['data']['hands']
                end
                data['data']['color'] = teban
                data
              end.call(s2, s3, s5)
            else
              @scanner.pos = s0
              :failed
            end
          end
        end
      end

      # hirate : "PI" xypiece* nl
      def parse_hirate
        s0 = @scanner.pos
        if match_str('PI') == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = []
          s3 = parse_xy_piece
          while s3 != :failed
            s2 << s3
            s3 = parse_xy_piece
          end
          if parse_nl == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            @reported_pos = s0
            s0 = -> (ps) do
              ret = { 'preset' => 'OTHER', 'data' => { 'board' => hirate } }
              ps.each do |piece|
                ret['data']['board'][piece['xy']['x'] - 1][piece['xy']['y'] - 1] = {}
              end
              ret
            end.call(s2)
          end
        end
        s0
      end

      # ikkatsu : ikkatsuline+
      def parse_ikkatsu
        s0 = @scanner.pos
        s2 = parse_ikkatsu_line
        if s2 == :failed
          s1 = :failed
        else
          s1 = []
          while s2 != :failed
            s1 << s2
            s2 = parse_ikkatsu_line
          end
        end
        if s1 != :failed
          @reported_pos = s0
          s1 = -> (lines) do
            board = []
            9.times do |i|
              line = []
              9.times do |j|
                line << lines[j][8 - i]
              end
              board << line
            end
            { 'preset' => 'OTHER', 'data' => { 'board' => board } }
          end.call(s1)
        end
        s1
      end

      # ikkatsuline : "P" [1-9] masu+ nl
      def parse_ikkatsu_line
        s0 = @scanner.pos
        if match_str('P') == :failed
          @scanner.pos = s0
          s0 = :failed
        elsif match_digit != :failed
          s4 = parse_masu
          if s4 == :failed
            s3 = :failed
          else
            s3 = []
            while s4 != :failed
              s3 << s4
              s4 = parse_masu
            end
          end
          if s3 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            s4 = parse_nl
            if s4 == :failed
              @scanner.pos = s0
              s0 = :failed
            else
              @reported_pos = s0
              s0 = s3
            end
          end
        else
          @scanner.pos = s0
          s0 = :failed
        end
        s0
      end

      # masu : teban piece | " * "
      def parse_masu
        s0 = @scanner.pos
        s1 = parse_teban
        if s1 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = parse_piece
          if s2 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            @reported_pos = s0
            s0 = { 'color' => s1, 'kind' => s2 }
          end
        end
        if s0 == :failed
          s0 = @scanner.pos
          if match_str(' * ') != :failed
            @reported_pos = s0
            s1 = {}
          end
          s0 = s1
        end
        s0
      end

      # komabetsu : komabetsuline*
      def parse_komabetsu
        s0 = @scanner.pos
        s1 = []
        s2 = parse_komabetsu_line
        while s2 != :failed
          s1 << s2
          s2 = parse_komabetsu_line
        end
        @reported_pos = s0
        transform_komabetsu_lines(s1)
      end

      # komabetsuline : "P" teban xypiece+ nl
      def parse_komabetsu_line
        s0 = @scanner.pos
        if match_str('P') == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = parse_teban
          if s2 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            s4 = parse_xy_piece
            if s4 == :failed
              s3 = :failed
            else
              s3 = []
              while s4 != :failed
                s3 << s4
                s4 = parse_xy_piece
              end
            end
            if s3 == :failed
              @scanner.pos = s0
              s0 = :failed
            elsif parse_nl != :failed
              @reported_pos = s0
              s0 = { 'teban' => s2, 'pieces' => s3 }
            else
              @scanner.pos = s0
              s0 = :failed
            end
          end
        end
        s0
      end

      # moves : firstboard move* comment*
      def parse_moves
        s0 = @scanner.pos
        s1 = parse_firstboard
        if s1 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = []
          s3 = parse_move
          while s3 != :failed
            s2 << s3
            s3 = parse_move
          end
          parse_comments
          @reported_pos = s0
          s0 = s2.unshift(s1)
        end
        s0
      end

      # firstboard : comment*
      def parse_firstboard
        s0 = @scanner.pos
        s1 = parse_comments
        @reported_pos = s0
        s1.empty? ? {} : { 'comments' => s1 }
      end

      # move : (normalmove | specialmove) time? comment*
      def parse_move
        s0 = @scanner.pos
        s1 = parse_normal_move
        s1 = parse_special_move if s1 == :failed
        if s1 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = parse_time
          s2 = nil if s2 == :failed
          s3 = parse_comments
          @reported_pos = s0
          s0 = -> (move, time, comments) do
            ret = {}
            ret['comments'] = comments unless comments.empty?
            ret['time'] = time if time
            if move['special']
              ret['special'] = move['special']
            else
              ret['move'] = move
            end
            ret
          end.call(s1, s2, s3)
        end
        s0
      end

      # normalmove : teban xy xy piece nl
      def parse_normal_move
        s0 = @scanner.pos
        s1 = parse_teban
        if s1 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = parse_xy
          if s2 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            s3 = parse_xy
            if s3 == :failed
              @scanner.pos = s0
              s0 = :failed
            else
              s4 = parse_piece
              if s4 == :failed
                @scanner.pos = s0
                s0 = :failed
              elsif parse_nl != :failed
                @reported_pos = s0
                s0 = -> (color, from, to, piece) do
                  ret = { 'color' => color, 'to' => to, 'piece' => piece }
                  ret['from'] = from if from['x'] != 0
                  ret
                end.call(s1, s2, s3, s4)
              else
                @scanner.pos = s0
                s0 = :failed
              end
            end
          end
        end
        s0
      end

      # specialmove : "%" [-+_A-Z]+ nl
      def parse_special_move
        s0 = @scanner.pos
        s1 = match_str('%')
        if s1 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s3 = match_regexp(/[-+_A-Z]/)
          if s3 == :failed
            s2 = :failed
          else
            s2 = []
            while s3 != :failed
              s2 << s3
              s3 = match_regexp(/[-+_A-Z]/)
            end
          end
          if s2 == :failed
            @scanner.pos = s0
            s0 = :failed
          elsif parse_nl != :failed
            @reported_pos = s0
            s0 = { 'special' => s2.join }
          else
            @scanner.pos = s0
            s0 = :failed
          end
        end
        s0
      end

      # teban : "+" | "-"
      def parse_teban
        s0 = @scanner.pos
        s1 = match_str('+')
        if s1 != :failed
          @reported_pos = s0
          s1 = 0
        end
        s0 = s1
        if s0 == :failed
          s0 = @scanner.pos
          s1 = match_str('-')
          if s1 != :failed
            @reported_pos = s0
            s1 = 1
          end
          s0 = s1
        end
        s0
      end

      # comment : "'" nonls nl
      def parse_comment
        s0 = @scanner.pos
        if match_str("'") == :failed
          @scanner.pos = s0
          :failed
        else
          s2 = parse_nonls
          if parse_nl == :failed
            @scanner.pos = s0
            :failed
          else
            @reported_pos = s0
            s2.join
          end
        end
      end

      # comments : comment*
      def parse_comments
        stack = []
        matched = parse_comment
        while matched != :failed
          stack << matched
          matched = parse_comment
        end
        stack
      end

      # time : "T" [0-9]* nl
      def parse_time
        s0 = @scanner.pos
        if match_str('T') == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = match_digits
          if parse_nl == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            @reported_pos = s0
            s0 = { 'now' => sec2time(s2.join.to_i) }
          end
        end
        s0
      end

      # xy : [0-9] [0-9]
      def parse_xy
        s0 = @scanner.pos
        s1 = match_digit
        if s1 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = match_digit
          if s2 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            @reported_pos = s0
            s0 = { 'x' => s1.to_i, 'y' => s2.to_i }
          end
        end
        s0
      end

      # piece : [A-Z] [A-Z]
      def parse_piece
        s0 = @scanner.pos
        s1 = match_regexp(/[A-Z]/)
        if s1 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = match_regexp(/[A-Z]/)
          if s2 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            @reported_pos = s0
            s0 = s1 + s2
          end
        end
        s0
      end

      # xypiece : xy piece
      def parse_xy_piece
        s0 = @scanner.pos
        s1 = parse_xy
        if s1 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s2 = parse_piece
          if s2 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            @reported_pos = s0
            s0 = { 'xy' => s1, 'piece' => s2 }
          end
        end
        s0
      end

      # nl : ("\r"? "\n") | " "* ","
      def parse_nl
        s0 = @scanner.pos
        s1 = match_str("\r")
        s1 = nil if s1 == :failed
        s2 = match_str("\n")
        if s2 == :failed
          @scanner.pos = s0
          s0 = :failed
        else
          s0 = [s1, s2]
        end
        if s0 == :failed
          s0 = @scanner.pos
          s1 = match_spaces
          s2 = match_str(',')
          if s2 == :failed
            @scanner.pos = s0
            s0 = :failed
          else
            s0 = [s1, s2]
          end
        end
        s0
      end

      # nonl : [^\r\n]
      def parse_nonl
        match_regexp(/[^\r\n]/)
      end

      # nonls : nonl*
      def parse_nonls
        stack = []
        matched = parse_nonl
        while matched != :failed
          stack << matched
          matched = parse_nonl
        end
        stack
      end

      # lines to jkf
      def transform_komabetsu_lines(lines)
        board = generate_empty_board
        hands = [
          { 'FU' => 0, 'KY' => 0, 'KE' => 0, 'GI' => 0, 'KI' => 0, 'KA' => 0, 'HI' => 0 },
          { 'FU' => 0, 'KY' => 0, 'KE' => 0, 'GI' => 0, 'KI' => 0, 'KA' => 0, 'HI' => 0 }
        ]
        all = { 'FU' => 18, 'KY' => 4, 'KE' => 4, 'GI' => 4, 'KI' => 4, 'KA' => 2, 'HI' => 2 }

        lines.each do |line|
          line['pieces'].each do |piece|
            xy = piece['xy']
            if xy['x'] == 0
              if piece['piece'] == 'AL'
                hands[line['teban']] = all
                return { 'preset' => 'OTHER', 'data' => { 'board' => board, 'hands' => hands } }
              end
              obj = hands[line['teban']]
              obj[piece['piece']] += 1
            else
              board[xy['x'] - 1][xy['y'] - 1] = { 'color' => line['teban'],
                                                  'kind' => piece['piece'] }
            end
            all[piece['piece']] -= 1 if piece['piece'] != 'OU'
          end
        end

        { 'preset' => 'OTHER', 'data' => { 'board' => board, 'hands' => hands } }
      end

      # return empty board jkf
      def generate_empty_board
        board = []
        9.times do |_i|
          line = []
          9.times do |_j|
            line << {}
          end
          board << line
        end
        board
      end

      # sec to time(m, s)
      def sec2time(sec)
        s = sec % 60
        m = (sec - s) / 60
        { 'm' => m, 's' => s }
      end

      # return hirate board jkf
      def hirate
        [
          [{ 'color' => 1, 'kind' => 'KY' }, {}, { 'color' => 1, 'kind' => 'FU' }, {}, {}, {},
           { 'color' => 0, 'kind' => 'FU' }, {}, { 'color' => 0, 'kind' => 'KY' }],
          [{ 'color' => 1, 'kind' => 'KE' }, { 'color' => 1, 'kind' => 'KA' },
           { 'color' => 1, 'kind' => 'FU' }, {}, {}, {}, { 'color' => 0, 'kind' => 'FU' },
           { 'color' => 0, 'kind' => 'HI' }, { 'color' => 0, 'kind' => 'KE' }],
          [{ 'color' => 1, 'kind' => 'GI' }, {}, { 'color' => 1, 'kind' => 'FU' }, {}, {}, {},
           { 'color' => 0, 'kind' => 'FU' }, {}, { 'color' => 0, 'kind' => 'GI' }],
          [{ 'color' => 1, 'kind' => 'KI' }, {}, { 'color' => 1, 'kind' => 'FU' }, {}, {}, {},
           { 'color' => 0, 'kind' => 'FU' }, {}, { 'color' => 0, 'kind' => 'KI' }],
          [{ 'color' => 1, 'kind' => 'OU' }, {}, { 'color' => 1, 'kind' => 'FU' }, {}, {}, {},
           { 'color' => 0, 'kind' => 'FU' }, {}, { 'color' => 0, 'kind' => 'OU' }],
          [{ 'color' => 1, 'kind' => 'KI' }, {}, { 'color' => 1, 'kind' => 'FU' }, {}, {}, {},
           { 'color' => 0, 'kind' => 'FU' }, {}, { 'color' => 0, 'kind' => 'KI' }],
          [{ 'color' => 1, 'kind' => 'GI' }, {}, { 'color' => 1, 'kind' => 'FU' }, {}, {}, {},
           { 'color' => 0, 'kind' => 'FU' }, {}, { 'color' => 0, 'kind' => 'GI' }],
          [{ 'color' => 1, 'kind' => 'KE' }, { 'color' => 1, 'kind' => 'HI' },
           { 'color' => 1, 'kind' => 'FU' }, {}, {}, {}, { 'color' => 0, 'kind' => 'FU' },
           { 'color' => 0, 'kind' => 'KA' }, { 'color' => 0, 'kind' => 'KE' }],
          [{ 'color' => 1, 'kind' => 'KY' }, {}, { 'color' => 1, 'kind' => 'FU' }, {}, {}, {},
           { 'color' => 0, 'kind' => 'FU' }, {}, { 'color' => 0, 'kind' => 'KY' }]
        ]
      end

      # normalize header key
      def normalize_header_key(key)
        {
          'EVENT' => '棋戦',
          'SITE' => '場所',
          'START_TIME' => '開始日時',
          'END_TIME' => '終了日時',
          'TIME_LIMIT' => '持ち時間'
        }[key] || key
      end
    end
  end
end