terminal.coffee

   1 # this file is used by the client and server.
   2
   3 # work around lack of module system in the browser:
   4 if exports?
   5         my_exports = exports
   6 else
   7         window.terminal = {}
   8         my_exports = window.terminal
   9
  10 if console?.log?
  11         log = -> console.log arguments...
  12 else
  13         log = -> null
  14
  15 alternate_charset_table = {
  16         A: "↑"
  17         B: "↓"
  18         C: "→"
  19         D: "←"
  20         E: "█"
  21         F: "▚"
  22         G: "☃"
  23         '_': " "
  24         '`': "◆"
  25         a: "▒"
  26         b: "␉"
  27         c: "␌"
  28         d: "␍"
  29         e: "␊"
  30         f: "°"
  31         g: "±"
  32         h: "␤"
  33         i: "␋"
  34         j: "┘"
  35         k: "┐"
  36         l: "┌"
  37         m: "└"
  38         n: "┼"
  39         o: "⎺"
  40         p: "⎻"
  41         q: "─"
  42         r: "⎼"
  43         s: "⎽"
  44         t: "├"
  45         u: "┤"
  46         v: "┴"
  47         w: "┬"
  48         x: "│"
  49         y: "≤"
  50         z: "≥"
  51         '{': "π"
  52         '|': "≠"
  53         '}': "£"
  54         '~': "·"
  55 }
  56
  57 class Terminal
  58         # public:
  59         constructor: (width, height) ->
  60                 @width = 1
  61                 @height = 1
  62                 @text = []
  63                 @attributes = []
  64                 @x = 0
  65                 @y = 0
  66                 @a = 0x000007 # cursor attributes
  67                 @partial = ''
  68                 @saved_normal_screen = null
  69                 @cursor_visible = true
  70                 @scroll_top = 0
  71                 @scroll_bottom = height - 1
  72                 @resize width, height
  73
  74         resize: (width, height) ->
  75                 # FIXME: write a version that retains some of the data
  76                 # FIXME: clamp variables (eg x, y, saved.*, scrolling region) if getting smaller
  77                 @width = width
  78                 @height = height
  79                 @text = []
  80                 @attributes = []
  81                 for y in [0...height]
  82                         @text[y] = []
  83                         @attributes[y] = []
  84                         for x in [0...width]
  85                                 @text[y].push ' '
  86                                 @attributes[y].push 0x07
  87
  88         # pass data from stdout
  89         update: (data) ->
  90                 return unless data?.length > 0
  91                 if @partial.length > 0
  92                         data = @partial + data
  93                         @partial = ''
  94                 parts = data.split(/\x1b/)
  95                 if parts.length > 1
  96                         if -1 is @escape_sequence_length parts[parts.length - 1]
  97                                 @partial = parts.pop()
  98                 for i in [0...parts.length]
  99                         if i is 0
 100                                 @update_text parts[i]
 101                         else
 102                                 @update_sequence_then_text parts[i]
 103                 return
 104
 105         add_new_line: ->
 106                 # clear the line at the top of the scrolling region
 107                 for i in [0...@width]
 108                         @text[@scroll_top][i] = ' '
 109                         @attributes[@scroll_top][i] = 0x07
 110
 111                 rearrange = (a) =>
 112                         return [
 113                                 a[0...@scroll_top]..., # up to but not including scroll top
 114                                 a[@scroll_top + 1 .. @scroll_bottom]..., # scroll region except top line of it
 115                                 a[@scroll_top], # top line of scroll region (already cleared)
 116                                 a[@scroll_bottom + 1 ... @height]... # rest of screen
 117                         ]
 118                 @text = rearrange @text
 119                 @attributes = rearrange @attributes
 120
 121                 # slide cursor up with rest of text
 122                 @y -= 1
 123
 124         wrap_to_next_line: ->
 125                 if @y is @scroll_bottom
 126                         @add_new_line()
 127                 @y += 1
 128                 @x = 0
 129
 130         # str has no escape sequences
 131         update_text: (str) ->
 132                 return unless str.length > 0
 133                 for c in str
 134                         switch c
 135                                 when '\t' # tab
 136                                         @update_text "        ".substr(@x % 8)
 137                                 when '\x07' # bell
 138                                         false
 139                                 when '\x0d' # cr
 140                                         @x = 0
 141                                 when '\x08' # backspace
 142                                         if @x is 0
 143                                                 @x = @width - 1
 144                                                 if @y > 0
 145                                                         @y -= 1
 146                                         else
 147                                                 @x -= 1
 148                                 when '\x0a', '\x0b' # lf, vertical tab (same thing)
 149                                         @wrap_to_next_line()
 150                                 when '\x0f'
 151                                         @alternate_charset = true
 152                                 when '\x0e'
 153                                         @alternate_charset = false
 154                                 else
 155                                         if @x >= @width
 156                                                 @wrap_to_next_line()
 157                                         if @alternate_charset
 158                                                 if alternate_charset_table[c]?
 159                                                         c = alternate_charset_table[c]
 160                                         @text[@y][@x] = c
 161                                         @attributes[@y][@x] = @a
 162                                         @x += 1
 163                 return
 164
 165         set_attribute_bits: (mask, value) ->
 166                 @a = ((@a & ~mask) | value)
 167
 168         # we're supposed to ignore leeding zeros, and while we're at it, lets swap
 169         # in the default for blank or missing values
 170         fix_esc_arg: (value, deef_alt) ->
 171                 if value? and value != ''
 172                         while value[0] is '0' and value.length > 1
 173                                 value = value.substr 1
 174                         return value
 175                 else
 176                         return deef_alt
 177
 178         # csi_@: rxvt does nothing I can detect
 179
 180         # "The auxiliary keypad keys will send ASCII codes corresponding to the
 181         # characters engraved on their keys." (numlock?)
 182         "esc_>": ->
 183
 184         # move cursor up
 185         csi_A: (lines) ->
 186                 lines = parseInt @fix_esc_arg lines, '1'
 187                 @y -= lines
 188                 if @y < 0
 189                         @y = 0
 190                 return
 191
 192         # move cursor down
 193         csi_B: (lines) ->
 194                 lines = parseInt @fix_esc_arg lines, '1'
 195                 @y += lines
 196                 if @y >= @height
 197                         @y = @height - 1
 198                 return
 199
 200         # move cursor right
 201         csi_C: (cols) ->
 202                 cols = parseInt @fix_esc_arg cols, '1'
 203                 @x += cols
 204                 if @x >= @width
 205                         @x = @width - 1
 206                 return
 207
 208         # move cursor left
 209         csi_D: (cols) ->
 210                 cols = parseInt @fix_esc_arg cols, '1'
 211                 @x -= cols
 212                 if @x < 0
 213                         @x = 0
 214                 return
 215
 216         # cursor set_row (y)
 217         csi_d: (row) ->
 218                 row = -1 + parseInt @fix_esc_arg row, '1'
 219                 @set_row_clamped row
 220                 return
 221
 222         # cursor column (x)
 223         csi_G: (col) ->
 224                 col = -1 + parseInt @fix_esc_arg col, '1'
 225                 @set_column_clamped col
 226                 return
 227
 228         # set cursor row (zero based)
 229         set_row_clamped: (row) ->
 230                 if row < 0
 231                         row = 0
 232                 if row >= @height
 233                         row = @height - 1
 234                 @y = row
 235                 return
 236         # set cursor column (zero based)
 237         set_column_clamped: (column) ->
 238                 if column < 0
 239                         column = 0
 240                 if column >= @width
 241                         column = @width - 1
 242                 @x = column
 243                 return
 244         # set cursor position (one based)
 245         csi_H: (row, column) ->
 246                 # handle blank/missing args and convert to 0 base
 247                 row = -1 + parseInt @fix_esc_arg row, '1'
 248                 column = -1 + parseInt @fix_esc_arg column, '1'
 249                 @set_row_clamped row
 250                 @set_column_clamped column
 251                 return
 252
 253         # clear to screen edge(es)
 254         csi_J: (direction) ->
 255                 switch @fix_esc_arg direction, '0'
 256                         when '0' # erase down
 257                                 # rest of current line
 258                                 @csi_K direction
 259                                 # rest of lines
 260                                 for row in [@y...@height]
 261                                         for i in [0...@width]
 262                                                 @text[row][i] = ' '
 263                                                 @attributes[row][i] = @a
 264                         when '1' # erase up
 265                                 # beginning of current line
 266                                 @csi_K direction
 267                                 # all previous lines
 268                                 for row in [0..@y]
 269                                         for i in [0...@width]
 270                                                 @text[row][i] = ' '
 271                                                 @attributes[row][i] = @a
 272                         when '2' # erase everything
 273                                 for row in [0...@height]
 274                                         for i in [0...@width]
 275                                                 @text[row][i] = ' '
 276                                                 @attributes[row][i] = @a
 277                         else
 278                                 log "confusing arg for csi_J: #{direction}"
 279                 return
 280
 281         # clear (some or all of) current line
 282         csi_K: (direction) ->
 283                 switch @fix_esc_arg direction, '0'
 284                         when '0' # erase to right
 285                                 for i in [@x...@width]
 286                                         @text[@y][i] = ' '
 287                                         @attributes[@y][i] = @a
 288                         when '1' # erase to left
 289                                 # @x can equal @width (after printing to right-most column)
 290                                 if @x < @width
 291                                         max = @x
 292                                 else
 293                                         max = @width - 1
 294                                 for i in [0..max]
 295                                         @text[@y][i] = ' '
 296                                         @attributes[@y][i] = @a
 297                         when '2' # erase whole line
 298                                 for i in [0...@width]
 299                                         @text[@y][i] = ' '
 300                                         @attributes[@y][i] = @a
 301                         else
 302                                 log "confusing arg for csi_K: #{direction}"
 303                 return
 304
 305         # move lines downwards (arg is how far)
 306         csi_L: (lines) ->
 307                 lines = parseInt @fix_esc_arg lines, '1'
 308
 309                 rearrange = (a) =>
 310                         return [
 311                                 a[0...@y]..., # keep everything above cursor
 312                                 a[@scroll_bottom - lines + 1 .. @scroll_bottom]..., # we'll clear these shortly
 313                                 a[@y..@scroll_bottom - lines]..., # lines that are moving down
 314                                 a[@scroll_bottom + 1 ... @height]... # rest of screen
 315                         ]
 316                 @text = rearrange @text
 317                 @attributes = rearrange @attributes
 318
 319                 # clear the lines we scrolled off (and put back in as "new")
 320                 for y in [@y...@y+lines]
 321                         for x in [0...@width]
 322                                 @text[y][x] = ' '
 323                                 @attributes[y][x] = 0x07
 324
 325         # move lines upwards (arg is how far)
 326         # this obliterates the line under the cursor and arg-1 following it
 327         csi_M: (lines) ->
 328                 lines = parseInt @fix_esc_arg lines, '1'
 329
 330                 rearrange = (a) =>
 331                         return [
 332                                 a[0 ... @y]..., # keep everything above cursor
 333                                 a[@y + lines .. @scroll_bottom]..., # lines we're moving up
 334                                 a[@y ... @y + lines]..., # recycle these
 335                                 a[@scroll_bottom + 1 ... @height]... # keep the rest
 336                         ]
 337                 @text = rearrange @text
 338                 @attributes = rearrange @attributes
 339
 340                 # clear the lines we're recycling
 341                 for y in [@scroll_bottom - lines + 1 .. @scroll_bottom]
 342                         for x in [0...@width]
 343                                 @text[y][x] = ' '
 344                                 @attributes[y][x] = 0x07
 345
 346         # delete chars (without moving the cursor)
 347         csi_X: (chars) ->
 348                 chars = parseInt @fix_esc_arg chars, '1'
 349                 x = @x
 350                 for c in [0...chars]
 351                         if x >= @width
 352                                 return
 353                         @text[@y][x] = ' '
 354                         @attributes[@y][x] = @a
 355                         x += 1
 356                 return
 357         "csi_@": (chars) ->
 358                 chars = parseInt @fix_esc_arg chars, '1'
 359                 if chars < 1
 360                         return
 361                 if chars > @width - @x
 362                         chars = @width - @x
 363                 else
 364                         dest = @width - 1
 365                         if dest >= @width
 366                                 dest = @width - 1
 367                         while dest - chars >= @x
 368                                 @text[@y][dest] = @text[@y][dest - chars]
 369                                 @attributes[@y][dest] = @attributes[@y][dest - chars]
 370                                 dest -= 1
 371                 @csi_X chars # clear
 372         csi_P: (chars) ->
 373                 chars = parseInt @fix_esc_arg chars, '1'
 374                 if chars < 1
 375                         return
 376                 if chars > @width - @x
 377                         chars = @width - @x
 378                 else
 379                         dest = @x
 380                         while dest < @width - chars
 381                                 @text[@y][dest] = @text[@y][dest + chars]
 382                                 @attributes[@y][dest] = @attributes[@y][dest + chars]
 383                                 dest += 1
 384                 # clear the space moved out of
 385                 x = @width - chars
 386                 while x < @width
 387                         @text[@y][x] = ' '
 388                         @attributes[@y][x] = @a
 389                         x += 1
 390
 391         # set modes not starting with "?"
 392         csi_h: (args...) ->
 393                 for i in args
 394                         arg = @fix_esc_arg i, ''
 395                         switch arg
 396                                 when '0' # error (ignored
 397                                         return
 398                                 when '2' # KAM -- keyboard action
 399                                         return
 400                                 when '4' # put cursor in "INSERT" mode
 401                                         return
 402                                 when '12' # turn local echo off (or on?)
 403                                         return
 404                                 # TODO when '20' LNM linefeed/newline
 405                                 else
 406                                         log "Unimplemented arg for csi_h: #{arg}"
 407         # set modes starting with "?"
 408         csiq_h: (args...) ->
 409                 for i in args
 410                         arg = @fix_esc_arg i, ''
 411                         switch arg
 412                                 when '1' # mode ?1
 413                                         # numlock on
 414                                         return
 415                                 when '25'
 416                                         @cursor_visible = true
 417                                 when '1000'
 418                                         # x11 normal mouse tracking
 419                                         return
 420                                 when '1049'
 421                                         if @saved_normal_screen?
 422                                                 log "ignoring request to switch to the alt screen because we're already on the alt screen"
 423                                                 return
 424                                         @saved_normal_screen = x: @x, y: @y, text: @text, attributes: @attributes
 425                                         @text = []
 426                                         @attributes = []
 427                                         for y in [0...@height]
 428                                                 @text[y] = []
 429                                                 @attributes[y] = []
 430                                                 for x in [0...@width]
 431                                                         @text[y].push ' '
 432                                                         @attributes[y].push 0x07
 433                                 else
 434                                         log "Unimplemented arg for csiq_h: #{arg}"
 435                 return
 436
 437         # reset (turn off) modes
 438         # note that modes starting with ? call csiq_l, not this
 439         csi_l: ->
 440                 for i in arguments
 441                         arg = @fix_esc_arg i, ''
 442                         switch arg
 443                                 when '0' # error (ignored
 444                                         return
 445                                 when '2' # KAM -- keyboard action
 446                                         return
 447                                 when '4' # put cursor in "REPLACE" mode
 448                                         return
 449                                 when '12' # turn local echo on (or off?)
 450                                         return
 451                                 # TODO when '20' LNM linefeed/newline
 452
 453         # reset (turn off) modes starting with ?
 454         # in st source, these are priv=true
 455         csiq_l: ->
 456                 args = []
 457                 for i in arguments
 458                         arg = @fix_esc_arg i, ''
 459                         switch arg
 460                                 when '1' # mode ?1 reset
 461                                         # numlock off
 462                                         return
 463                                 when '12' # mode ?12
 464                                         # stop blinking the cursor (ignored)
 465                                         return
 466                                 when '25' # mode ?25 reset
 467                                         @cursor_visible = false
 468                                 when '0', '2', '3', '4', '8', '18', '19', '42', '12'
 469                                         # st ignores all of these
 470                                         return
 471                                 when '9', '1000', '1002', '1003', '1004', '1006'
 472                                         # mouse reporting and such (ignored)
 473                                         return
 474                                 when '1049'
 475                                         if not @saved_normal_screen?
 476                                                 log "ignoring request to switch to the normal screen because we're already on the normal screen"
 477                                                 return
 478                                         @x = @saved_normal_screen.x
 479                                         @y = @saved_normal_screen.y
 480                                         @text = @saved_normal_screen.text
 481                                         @attributes = @saved_normal_screen.attributes
 482                                         @saved_normal_screen = null
 483                                 else
 484                                         log "Unimplemented arg for csiq_l: #{arg}"
 485                 return
 486
 487         # set color, bold, underline, etc
 488         csi_m: ->
 489                 args = []
 490                 for i in arguments
 491                         args.push @fix_esc_arg i, '0'
 492
 493                 while args.length > 0
 494                         arg = args.shift()
 495                         switch arg
 496                                 # remove all style/color
 497                                 when '0'
 498                                         @a = 0x07
 499
 500                                 # style attributes
 501                                 when '1' # bold
 502                                         @set_attribute_bits 0x010000, 0x010000
 503                                 when '3' # italic (rare)
 504                                         @set_attribute_bits 0x200000, 0x200000
 505                                 when '4' # underline
 506                                         @set_attribute_bits 0x020000, 0x020000
 507                                 when '5' # blink
 508                                         @set_attribute_bits 0x040000, 0x040000
 509                                 when '7' # inverse
 510                                         @set_attribute_bits 0x080000, 0x080000
 511                                 when '8' # invisible. urivt ignores this
 512                                         @set_attribute_bits 0x100000, 0x100000
 513
 514                                 # disable style attributes
 515                                 when '21' # not bold (rare)
 516                                         @set_attribute_bits 0x010000, 0
 517                                 when '22' # not bold
 518                                         @set_attribute_bits 0x010000, 0
 519                                 when '23' # not italic (rare)
 520                                         @set_attribute_bits 0x200000, 0
 521                                 when '24' # not underline
 522                                         @set_attribute_bits 0x020000, 0
 523                                 when '25' # not blink
 524                                         @set_attribute_bits 0x040000, 0
 525                                 when '27' # not inverse
 526                                         @set_attribute_bits 0x080000, 0
 527                                 when '28' # not invisible
 528                                         @set_attribute_bits 0x100000, 0
 529
 530                                 when '100' # reset colors but not other attributes
 531                                         @set_attribute_bits 0xffff, 0x0007
 532
 533                                 # 8 fg colors
 534                                 when '30' # fg black
 535                                         @set_attribute_bits 0xff, 0x00
 536                                 when '31' # fg red
 537                                         @set_attribute_bits 0xff, 0x01
 538                                 when '32' # fg green
 539                                         @set_attribute_bits 0xff, 0x02
 540                                 when '33' # fg yellow
 541                                         @set_attribute_bits 0xff, 0x03
 542                                 when '34' # fg blue
 543                                         @set_attribute_bits 0xff, 0x04
 544                                 when '35' # fg magenta
 545                                         @set_attribute_bits 0xff, 0x05
 546                                 when '36' # fg cyan
 547                                         @set_attribute_bits 0xff, 0x06
 548                                 when '37', '39' # fg white  (39 is default)
 549                                         @set_attribute_bits 0xff, 0x07
 550
 551                                 when '38'
 552                                         if args.length >= 2 and args[0] is '5'
 553                                                 args.shift()
 554                                                 @set_attribute_bits 0xff, (0xff & args.shift())
 555                                         else
 556                                                 @set_attribute_bits 0x20000, 0x20000
 557
 558                                 # 8 bg colors
 559                                 when '40' # bg black
 560                                         @set_attribute_bits 0xff00, 0x0000
 561                                 when '41' # bg red
 562                                         @set_attribute_bits 0xff00, 0x0100
 563                                 when '42' # bg green
 564                                         @set_attribute_bits 0xff00, 0x0200
 565                                 when '43' # bg yellow
 566                                         @set_attribute_bits 0xff00, 0x0300
 567                                 when '44' # bg blue
 568                                         @set_attribute_bits 0xff00, 0x0400
 569                                 when '45' # bg magenta
 570                                         @set_attribute_bits 0xff00, 0x0500
 571                                 when '46' # bg cyan
 572                                         @set_attribute_bits 0xff00, 0x0600
 573                                 when '47' # bg white
 574                                         @set_attribute_bits 0xff00, 0x0700
 575                                 when '49' # bg default
 576                                         @set_attribute_bits 0xff00, 0x0000
 577
 578                                 when '48'
 579                                         if args.length >= 2 and args[0] is '5'
 580                                                 args.shift()
 581                                                 @set_attribute_bits 0xff00, ((0xff & args.shift()) << 8)
 582                                         else
 583                                                 @set_attribute_bits 0x20000, 0x20000
 584
 585                                 # bright fg colors
 586                                 when '90' # fg bright black
 587                                         @set_attribute_bits 0xff, 0x08
 588                                 when '91' # fg bright red
 589                                         @set_attribute_bits 0xff, 0x09
 590                                 when '92' # fg bright green
 591                                         @set_attribute_bits 0xff, 0x0a
 592                                 when '93' # fg bright yellow
 593                                         @set_attribute_bits 0xff, 0x0b
 594                                 when '94' # fg bright blue
 595                                         @set_attribute_bits 0xff, 0x0c
 596                                 when '95' # fg bright magenta
 597                                         @set_attribute_bits 0xff, 0x0d
 598                                 when '96' # fg bright cyan
 599                                         @set_attribute_bits 0xff, 0x0e
 600                                 when '97' # fg bright white
 601                                         @set_attribute_bits 0xff, 0x0f
 602
 603                                 # bright bg colors
 604                                 when '100' # bg bright black
 605                                         @set_attribute_bits 0xff00, 0x0800
 606                                 when '101' # bg bright red
 607                                         @set_attribute_bits 0xff00, 0x0900
 608                                 when '102' # bg bright green
 609                                         @set_attribute_bits 0xff00, 0x0a00
 610                                 when '103' # bg bright yellow
 611                                         @set_attribute_bits 0xff00, 0x0b00
 612                                 when '104' # bg bright blue
 613                                         @set_attribute_bits 0xff00, 0x0c00
 614                                 when '105' # bg bright magenta
 615                                         @set_attribute_bits 0xff00, 0x0d00
 616                                 when '106' # bg bright cyan
 617                                         @set_attribute_bits 0xff00, 0x0e00
 618                                 when '107' # bg bright white
 619                                         @set_attribute_bits 0xff00, 0x0f00
 620
 621                                 else
 622                                         # if we don't recognize the style, go back to default
 623                                         log "unrecognized csi_m arg: \"#{arg}\""
 624                                         @a = 0
 625                 return
 626
 627         # set scroll region
 628         csi_r: (top, bottom) ->
 629                 top = -1 + parseInt @fix_esc_arg top, '1'
 630                 bottom = -1 + parseInt @fix_esc_arg bottom, '10000'
 631                 if top < 0
 632                         top = 0
 633                 if bottom >= @height
 634                         bottom = @height - 1
 635                 @scroll_top = top
 636                 @scroll_bottom = bottom
 637                 return
 638
 639         # move cursor up one line, if it's at the top, scroll everything down
 640         esc_M: ->
 641                 if @y > 0
 642                         @csi_A '1'
 643                 else
 644                         @csi_L '1'
 645
 646         # esc ]
 647         "esc_]": (seq) ->
 648                 sem = seq.indexOf ';'
 649                 if sem < 1 || seq[0] isnt '0'
 650                         log "Unimplemented esc_] (OS command) sequence: #{seq}"
 651                         return
 652                 if window?
 653                         title = seq.substr sem + 1
 654                         title = title.substr 0, title.length - 1
 655                         window.document.title = title
 656
 657         # "The auxiliary keypad keys will transmit control sequences."
 658         "esc_=": ->
 659
 660         # esc )
 661         "esc_)": ->
 662                 @alternate_charset = true
 663         # esc ( 0
 664         gzd4_0: ->
 665                 @alternate_charset = true
 666         # esc ( B
 667         gzd4_B: ->
 668                 @alternate_charset = false
 669
 670         esc_n: ->
 671                 @alternate_charset = false
 672
 673         esc_o: ->
 674                 @alternate_charset = true
 675
 676         # str is the whole escape sequence (minus the esc character)
 677         update_sequence: (str) ->
 678                 if str[0] is '['
 679                         if str[1] is '?'
 680                                 method_prefix = 'csiq_'
 681                                 args = str.substr(2, str.length - 3).split ';'
 682                         else
 683                                 method_prefix = 'csi_'
 684                                 args = str.substr(1, str.length - 2).split ';'
 685                         method_name = method_prefix + str.substr str.length - 1
 686                 else if str[0] is '(' # character set
 687                         method_name = 'gzd4_' + str.substr 1, 1
 688                         args = [str.substr 1]
 689                 else
 690                         method_name = 'esc_' + str.substr 0, 1
 691                         args = [str.substr 1]
 692                 method = @[method_name]
 693                 if not method?
 694                         log "Unimplemented #{method_name}, code: ESC#{str}"
 695                         return
 696                 method.apply this, args
 697
 698         update_sequence_then_text: (str) ->
 699                 len = @escape_sequence_length str
 700                 if len is -1
 701                         log "couldn't find escape sequence here: #{str.substr 0, 25}"
 702                         @update_text "ESC" + str
 703                 else
 704                         @update_sequence str.substr 0, len
 705                         @update_text str.substr len
 706
 707         escape_sequence_length: (str) ->
 708                 if str[0] is '['
 709                         parts = str.match(/^\[[0-9;?]{0,25}./)
 710                         return -1 unless parts?
 711                         return parts[0].length
 712                 else if str[0] is '('
 713                         if str.length == 1
 714                                 return -1
 715                         if str[1] is '!' or str[1] is '%'
 716                                 return 3
 717                         else
 718                                 return 2
 719                 else if str[0] is ']'
 720                         st = str.indexOf "\u0007"
 721                         if st is -1
 722                                 return -1
 723                         return st + 1
 724                 else
 725                         #log "non[: ESC#{str.substr 0, 10}"
 726                         if str.length >= 1
 727                                 return 1
 728                         else
 729                                 return -1
 730
 731 my_exports.new = (width, height) ->
 732         return new Terminal width, height