BigW Consortium Gitlab

ansi2html.rb 8.24 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
# ANSI color library
#
# Implementation per http://en.wikipedia.org/wiki/ANSI_escape_code
module Ci
  module Ansi2html
    # keys represent the trailing digit in color changing command (30-37, 40-47, 90-97. 100-107)
    COLOR = {
      0 => 'black', # not that this is gray in the intense color table
      1 => 'red',
      2 => 'green',
      3 => 'yellow',
      4 => 'blue',
      5 => 'magenta',
      6 => 'cyan',
      7 => 'white', # not that this is gray in the dark (aka default) color table
16
    }.freeze
17 18 19 20 21 22

    STYLE_SWITCHES = {
      bold:       0x01,
      italic:     0x02,
      underline:  0x04,
      conceal:    0x08,
23
      cross:      0x10
24
    }.freeze
25

26 27
    def self.convert(ansi, state = nil)
      Converter.new.convert(ansi, state)
28 29 30 31
    end

    class Converter
      def on_0(s) reset()                            end
32

33
      def on_1(s) enable(STYLE_SWITCHES[:bold])      end
34

35
      def on_3(s) enable(STYLE_SWITCHES[:italic])    end
36

37
      def on_4(s) enable(STYLE_SWITCHES[:underline]) end
38

39
      def on_8(s) enable(STYLE_SWITCHES[:conceal])   end
40

41 42 43
      def on_9(s) enable(STYLE_SWITCHES[:cross])     end

      def on_21(s) disable(STYLE_SWITCHES[:bold])      end
44

45
      def on_22(s) disable(STYLE_SWITCHES[:bold])      end
46

47
      def on_23(s) disable(STYLE_SWITCHES[:italic])    end
48

49
      def on_24(s) disable(STYLE_SWITCHES[:underline]) end
50

51
      def on_28(s) disable(STYLE_SWITCHES[:conceal])   end
52

53 54 55
      def on_29(s) disable(STYLE_SWITCHES[:cross])     end

      def on_30(s) set_fg_color(0) end
56

57
      def on_31(s) set_fg_color(1) end
58

59
      def on_32(s) set_fg_color(2) end
60

61
      def on_33(s) set_fg_color(3) end
62

63
      def on_34(s) set_fg_color(4) end
64

65
      def on_35(s) set_fg_color(5) end
66

67
      def on_36(s) set_fg_color(6) end
68

69
      def on_37(s) set_fg_color(7) end
70

71
      def on_38(s) set_fg_color_256(s) end
72

73 74 75
      def on_39(s) set_fg_color(9) end

      def on_40(s) set_bg_color(0) end
76

77
      def on_41(s) set_bg_color(1) end
78

79
      def on_42(s) set_bg_color(2) end
80

81
      def on_43(s) set_bg_color(3) end
82

83
      def on_44(s) set_bg_color(4) end
84

85
      def on_45(s) set_bg_color(5) end
86

87
      def on_46(s) set_bg_color(6) end
88

89
      def on_47(s) set_bg_color(7) end
90

91
      def on_48(s) set_bg_color_256(s) end
92

93 94 95
      def on_49(s) set_bg_color(9) end

      def on_90(s) set_fg_color(0, 'l') end
96

97
      def on_91(s) set_fg_color(1, 'l') end
98

99
      def on_92(s) set_fg_color(2, 'l') end
100

101
      def on_93(s) set_fg_color(3, 'l') end
102

103
      def on_94(s) set_fg_color(4, 'l') end
104

105
      def on_95(s) set_fg_color(5, 'l') end
106

107
      def on_96(s) set_fg_color(6, 'l') end
108

109
      def on_97(s) set_fg_color(7, 'l') end
110

111 112 113
      def on_99(s) set_fg_color(9, 'l') end

      def on_100(s) set_bg_color(0, 'l') end
114

115
      def on_101(s) set_bg_color(1, 'l') end
116

117
      def on_102(s) set_bg_color(2, 'l') end
118

119
      def on_103(s) set_bg_color(3, 'l') end
120

121
      def on_104(s) set_bg_color(4, 'l') end
122

123
      def on_105(s) set_bg_color(5, 'l') end
124

125
      def on_106(s) set_bg_color(6, 'l') end
126

127
      def on_107(s) set_bg_color(7, 'l') end
128

129 130
      def on_109(s) set_bg_color(9, 'l') end

131 132
      attr_accessor :offset, :n_open_tags, :fg_color, :bg_color, :style_mask

133
      STATE_PARAMS = [:offset, :n_open_tags, :fg_color, :bg_color, :style_mask].freeze
134

135
      def convert(stream, new_state)
136
        reset_state
137 138 139 140 141 142 143 144 145 146 147 148 149 150
        restore_state(new_state, stream) if new_state.present?

        append = false
        truncated = false

        cur_offset = stream.tell
        if cur_offset > @offset
          @offset = cur_offset
          truncated = true
        else
          stream.seek(@offset)
          append = @offset > 0
        end
        start_offset = @offset
151 152

        open_new_tag
153

154 155 156 157 158 159 160 161 162 163 164 165 166 167 168
        stream.each_line do |line|
          s = StringScanner.new(line)
          until s.eos?
            if s.scan(/\e([@-_])(.*?)([@-~])/)
              handle_sequence(s)
            elsif s.scan(/\e(([@-_])(.*?)?)?$/)
              break
            elsif s.scan(/</)
              @out << '&lt;'
            elsif s.scan(/\r?\n/)
              @out << '<br>'
            else
              @out << s.scan(/./m)
            end
            @offset += s.matched_size
169 170 171 172
          end
        end

        close_open_tags()
173

174
        OpenStruct.new(
175
          html: @out.force_encoding(Encoding.default_external),
176 177 178 179 180 181 182
          state: state,
          append: append,
          truncated: truncated,
          offset: start_offset,
          size: stream.tell - start_offset,
          total: stream.size
        )
183 184 185 186 187 188 189 190 191 192
      end

      def handle_sequence(s)
        indicator = s[1]
        commands = s[2].split ';'
        terminator = s[3]

        # We are only interested in color and text style changes - triggered by
        # sequences starting with '\e[' and ending with 'm'. Any other control
        # sequence gets stripped (including stuff like "delete last line")
Douwe Maan committed
193
        return unless indicator == '[' && terminator == 'm'
194 195 196 197 198 199 200 201 202 203

        close_open_tags()

        if commands.empty?()
          reset()
          return
        end

        evaluate_command_stack(commands)

204 205 206 207 208 209 210 211 212 213 214 215 216 217
        open_new_tag
      end

      def evaluate_command_stack(stack)
        return unless command = stack.shift()

        if self.respond_to?("on_#{command}", true)
          self.send("on_#{command}", stack)
        end

        evaluate_command_stack(stack)
      end

      def open_new_tag
218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234
        css_classes = []

        unless @fg_color.nil?
          fg_color = @fg_color
          # Most terminals show bold colored text in the light color variant
          # Let's mimic that here
          if @style_mask & STYLE_SWITCHES[:bold] != 0
            fg_color.sub!(/fg-(\w{2,}+)/, 'fg-l-\1')
          end
          css_classes << fg_color
        end
        css_classes << @bg_color unless @bg_color.nil?

        STYLE_SWITCHES.each do |css_class, flag|
          css_classes << "term-#{css_class}" if @style_mask & flag != 0
        end

235
        return if css_classes.empty?
236 237 238 239 240 241 242 243 244 245 246 247

        @out << %{<span class="#{css_classes.join(' ')}">}
        @n_open_tags += 1
      end

      def close_open_tags
        while @n_open_tags > 0
          @out << %{</span>}
          @n_open_tags -= 1
        end
      end

248 249 250 251 252 253 254 255
      def reset_state
        @offset = 0
        @n_open_tags = 0
        @out = ''
        reset
      end

      def state
256
        state = STATE_PARAMS.inject({}) do |h, param|
257 258 259
          h[param] = send(param)
          h
        end
260
        Base64.urlsafe_encode64(state.to_json)
261 262
      end

263
      def restore_state(new_state, stream)
264 265
        state = Base64.urlsafe_decode64(new_state)
        state = JSON.parse(state, symbolize_names: true)
266
        return if state[:offset].to_i > stream.size
267

268
        STATE_PARAMS.each do |param|
269
          send("#{param}=".to_sym, state[param])
270 271 272
        end
      end

273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331
      def reset
        @fg_color = nil
        @bg_color = nil
        @style_mask = 0
      end

      def enable(flag)
        @style_mask |= flag
      end

      def disable(flag)
        @style_mask &= ~flag
      end

      def set_fg_color(color_index, prefix = nil)
        @fg_color = get_term_color_class(color_index, ["fg", prefix])
      end

      def set_bg_color(color_index, prefix = nil)
        @bg_color = get_term_color_class(color_index, ["bg", prefix])
      end

      def get_term_color_class(color_index, prefix)
        color_name = COLOR[color_index]
        return nil if color_name.nil?

        get_color_class(["term", prefix, color_name])
      end

      def set_fg_color_256(command_stack)
        css_class = get_xterm_color_class(command_stack, "fg")
        @fg_color = css_class unless css_class.nil?
      end

      def set_bg_color_256(command_stack)
        css_class = get_xterm_color_class(command_stack, "bg")
        @bg_color = css_class unless css_class.nil?
      end

      def get_xterm_color_class(command_stack, prefix)
        # the 38 and 48 commands have to be followed by "5" and the color index
        return unless command_stack.length >= 2
        return unless command_stack[0] == "5"

        command_stack.shift() # ignore the "5" command
        color_index = command_stack.shift().to_i

        return unless color_index >= 0
        return unless color_index <= 255

        get_color_class(["xterm", prefix, color_index])
      end

      def get_color_class(segments)
        [segments].flatten.compact.join('-')
      end
    end
  end
end