" Language:     Colored CSS Color Preview
" Maintainer:   Niklas Hofer <niklas+vim@lanpartei.de>
" URL:          svn://lanpartei.de/vimrc/after/syntax/css.vim
" Last Change:  2008 Feb 12
" Licence:      No Warranties. Do whatever you want with this. But please tell me!
" Version:      0.6
 
function! s:FGforBG(bg)
  " takes a 6hex color code and returns a matching color that is visible
  let pure = substitute(a:bg,'^#','','')
  let r = eval('0x'.pure[0].pure[1])
  let g = eval('0x'.pure[2].pure[3])
  let b = eval('0x'.pure[4].pure[5])
  if r*30 + g*59 + b*11 > 12000
    return '#000000'
  else
    return '#ffffff'
  end
endfunction
 
function! s:SetMatcher(clr,pat)
  let group = 'cssColor'.substitute(a:clr,'^#','','')
  redir => s:currentmatch
  silent! exe 'syn list '.group
  redir END
  let g:currentmatch = s:currentmatch
  if s:currentmatch !~ a:pat.'\/'
    exe 'syn match '.group.' /'.a:pat.'/ contained'
    exe 'syn cluster cssColors add='.group
    if has('gui_running')
      exe 'hi '.group.' guifg='.s:FGforBG(a:clr)
      exe 'hi '.group.' guibg='.a:clr
    elseif &t_Co == 256
      exe 'hi '.group.' ctermfg='.s:Rgb2xterm(s:FGforBG(a:clr))
      exe 'hi '.group.' ctermbg='.s:Rgb2xterm(a:clr)
    endif
    return 1
  else
    return 0
  endif
endfunction
 
"" the 6 value iterations in the xterm color cube
let s:valuerange = [ 0x00, 0x5F, 0x87, 0xAF, 0xD7, 0xFF ]
 
"" 16 basic colors
let s:basic16 = [ [ 0x00, 0x00, 0x00 ], [ 0xCD, 0x00, 0x00 ], [ 0x00, 0xCD, 0x00 ], [ 0xCD, 0xCD, 0x00 ], [ 0x00, 0x00, 0xEE ], [ 0xCD, 0x00, 0xCD ], [ 0x00, 0xCD, 0xCD ], [ 0xE5, 0xE5, 0xE5 ], [ 0x7F, 0x7F, 0x7F ], [ 0xFF, 0x00, 0x00 ], [ 0x00, 0xFF, 0x00 ], [ 0xFF, 0xFF, 0x00 ], [ 0x5C, 0x5C, 0xFF ], [ 0xFF, 0x00, 0xFF ], [ 0x00, 0xFF, 0xFF ], [ 0xFF, 0xFF, 0xFF ] ]
 
function! s:Xterm2rgb(color) 
  " 16 basic colors
  let r=0
  let g=0
  let b=0
  if a:color<16
    let r = s:basic16[a:color][0]
    let g = s:basic16[a:color][1]
    let b = s:basic16[a:color][2]
  endif
 
  " color cube color
  if a:color>=16 && a:color<=232
    let color=a:color-16
    let r = s:valuerange[(color/36)%6]
    let g = s:valuerange[(color/6)%6]
    let b = s:valuerange[color%6]
  endif
 
  " gray tone
  if a:color>=233 && a:color<=253
    let r=8+(a:color-232)*0x0a
    let g=r
    let b=r
  endif
  let rgb=[r,g,b]
  return rgb
endfunction
 
function! s:pow(x, n)
  let x = a:x
  for i in range(a:n-1)
    let x = x*a:x
  return x
endfunction
 
let s:colortable=[]
for c in range(0, 254)
  let color = s:Xterm2rgb(c)
  call add(s:colortable, color)
endfor
 
" selects the nearest xterm color for a rgb value like #FF0000
function! s:Rgb2xterm(color)
  let best_match=0
  let smallest_distance = 10000000000
  let r = eval('0x'.a:color[1].a:color[2])
  let g = eval('0x'.a:color[3].a:color[4])
  let b = eval('0x'.a:color[5].a:color[6])
  for c in range(0,254)
    let d = s:pow(s:colortable[c][0]-r,2) + s:pow(s:colortable[c][1]-g,2) + s:pow(s:colortable[c][2]-b,2)
    if d<smallest_distance
      let smallest_distance = d
      let best_match = c
    endif
  endfor
  return best_match
endfunction
 
function! s:SetNamedColor(clr,name)
  let group = 'cssColor'.substitute(a:clr,'^#','','')
  exe 'syn keyword '.group.' '.a:name.' contained'
  exe 'syn cluster cssColors add='.group
  if has('gui_running')
    exe 'hi '.group.' guifg='.s:FGforBG(a:clr)
    exe 'hi '.group.' guibg='.a:clr
  elseif &t_Co == 256
    exe 'hi '.group.' ctermfg='.s:Rgb2xterm(s:FGforBG(a:clr))
    exe 'hi '.group.' ctermbg='.s:Rgb2xterm(a:clr)
  endif
  return 23
endfunction
 
function! s:func2hex(rgb)
  let color = eval('[' . matchstr(a:rgb, '[0-9]\{1,3\}\s*,\s*[0-9]\{1,3\}\s*,\s*[0-9]\{1,3\}') . ']')
  return '#' . printf('%02x', color[0]) . printf('%02x', color[1]) . printf('%02x', color[2])
endfunction
 
function! s:PreviewCSSColorInLine(where)
  " TODO use cssColor matchdata
  let foundcolor = matchstr( getline(a:where), '#[0-9A-Fa-f]\{3,6\}\>\|rgba\?(\s*[0-9]\+\s*,\s*[0-9]\+\s*,\s*[0-9]\+\s*\(,\s*[0-9.]\+\s*\)\?)' )
  let color = ''
  if foundcolor != ''
    if foundcolor =~ '#\x\{6}$'
      let color = foundcolor
    elseif foundcolor =~ '#\x\{3}$'
      let color = substitute(foundcolor, '\(\x\)\(\x\)\(\x\)', '\1\1\2\2\3\3', '')
    elseif foundcolor =~ '^rgba\?([0-9 ,.]\+)$'
      let color = s:func2hex(foundcolor)
    else
      let color = ''
    endif
    if color != ''
      return s:SetMatcher(color,foundcolor)
    else
      return 0
    endif
  else
    return 0
  endif
endfunction
 
if has("gui_running") || &t_Co==256
  " HACK modify cssDefinition to add @cssColors to its contains
  redir => s:olddef
  silent!  syn list cssDefinition
  redir END
  if s:olddef != ''
    let s:b = strridx(s:olddef,'matchgroup')
    if s:b != -1
      exe 'syn region cssDefinition '.strpart(s:olddef,s:b).',@cssColors'
    endif
  endif
 
  " w3c Colors
  let i = s:SetNamedColor('#800000', 'maroon')
  let i = s:SetNamedColor('#ff0000', 'red')
  let i = s:SetNamedColor('#ffA500', 'orange')
  let i = s:SetNamedColor('#ffff00', 'yellow')
  let i = s:SetNamedColor('#808000', 'olive')
  let i = s:SetNamedColor('#800080', 'purple')
  let i = s:SetNamedColor('#ff00ff', 'fuchsia')
  let i = s:SetNamedColor('#ffffff', 'white')
  let i = s:SetNamedColor('#00ff00', 'lime')
  let i = s:SetNamedColor('#008000', 'green')
  let i = s:SetNamedColor('#000080', 'navy')
  let i = s:SetNamedColor('#0000ff', 'blue')
  let i = s:SetNamedColor('#00ffff', 'aqua')
  let i = s:SetNamedColor('#008080', 'teal')
  let i = s:SetNamedColor('#000000', 'black')
  let i = s:SetNamedColor('#c0c0c0', 'silver')
  let i = s:SetNamedColor('#808080', 'gray')
 
  " extra colors
  let i = s:SetNamedColor('#F0F8FF','AliceBlue')
  let i = s:SetNamedColor('#FAEBD7','AntiqueWhite')
  let i = s:SetNamedColor('#7FFFD4','Aquamarine')
  let i = s:SetNamedColor('#F0FFFF','Azure')
  let i = s:SetNamedColor('#F5F5DC','Beige')
  let i = s:SetNamedColor('#FFE4C4','Bisque')
  let i = s:SetNamedColor('#FFEBCD','BlanchedAlmond')
  let i = s:SetNamedColor('#8A2BE2','BlueViolet')
  let i = s:SetNamedColor('#A52A2A','Brown')
  let i = s:SetNamedColor('#DEB887','BurlyWood')
  let i = s:SetNamedColor('#5F9EA0','CadetBlue')
  let i = s:SetNamedColor('#7FFF00','Chartreuse')
  let i = s:SetNamedColor('#D2691E','Chocolate')
  let i = s:SetNamedColor('#FF7F50','Coral')
  let i = s:SetNamedColor('#6495ED','CornflowerBlue')
  let i = s:SetNamedColor('#FFF8DC','Cornsilk')
  let i = s:SetNamedColor('#DC143C','Crimson')
  let i = s:SetNamedColor('#00FFFF','Cyan')
  let i = s:SetNamedColor('#00008B','DarkBlue')
  let i = s:SetNamedColor('#008B8B','DarkCyan')
  let i = s:SetNamedColor('#B8860B','DarkGoldenRod')
  let i = s:SetNamedColor('#A9A9A9','DarkGray')
  let i = s:SetNamedColor('#A9A9A9','DarkGrey')
  let i = s:SetNamedColor('#006400','DarkGreen')
  let i = s:SetNamedColor('#BDB76B','DarkKhaki')
  let i = s:SetNamedColor('#8B008B','DarkMagenta')
  let i = s:SetNamedColor('#556B2F','DarkOliveGreen')
  let i = s:SetNamedColor('#FF8C00','Darkorange')
  let i = s:SetNamedColor('#9932CC','DarkOrchid')
  let i = s:SetNamedColor('#8B0000','DarkRed')
  let i = s:SetNamedColor('#E9967A','DarkSalmon')
  let i = s:SetNamedColor('#8FBC8F','DarkSeaGreen')
  let i = s:SetNamedColor('#483D8B','DarkSlateBlue')
  let i = s:SetNamedColor('#2F4F4F','DarkSlateGray')
  let i = s:SetNamedColor('#2F4F4F','DarkSlateGrey')
  let i = s:SetNamedColor('#00CED1','DarkTurquoise')
  let i = s:SetNamedColor('#9400D3','DarkViolet')
  let i = s:SetNamedColor('#FF1493','DeepPink')
  let i = s:SetNamedColor('#00BFFF','DeepSkyBlue')
  let i = s:SetNamedColor('#696969','DimGray')
  let i = s:SetNamedColor('#696969','DimGrey')
  let i = s:SetNamedColor('#1E90FF','DodgerBlue')
  let i = s:SetNamedColor('#B22222','FireBrick')
  let i = s:SetNamedColor('#FFFAF0','FloralWhite')
  let i = s:SetNamedColor('#228B22','ForestGreen')
  let i = s:SetNamedColor('#DCDCDC','Gainsboro')
  let i = s:SetNamedColor('#F8F8FF','GhostWhite')
  let i = s:SetNamedColor('#FFD700','Gold')
  let i = s:SetNamedColor('#DAA520','GoldenRod')
  let i = s:SetNamedColor('#808080','Grey')
  let i = s:SetNamedColor('#ADFF2F','GreenYellow')
  let i = s:SetNamedColor('#F0FFF0','HoneyDew')
  let i = s:SetNamedColor('#FF69B4','HotPink')
  let i = s:SetNamedColor('#CD5C5C','IndianRed')
  let i = s:SetNamedColor('#4B0082','Indigo')
  let i = s:SetNamedColor('#FFFFF0','Ivory')
  let i = s:SetNamedColor('#F0E68C','Khaki')
  let i = s:SetNamedColor('#E6E6FA','Lavender')
  let i = s:SetNamedColor('#FFF0F5','LavenderBlush')
  let i = s:SetNamedColor('#7CFC00','LawnGreen')
  let i = s:SetNamedColor('#FFFACD','LemonChiffon')
  let i = s:SetNamedColor('#ADD8E6','LightBlue')
  let i = s:SetNamedColor('#F08080','LightCoral')
  let i = s:SetNamedColor('#E0FFFF','LightCyan')
  let i = s:SetNamedColor('#FAFAD2','LightGoldenRodYellow')
  let i = s:SetNamedColor('#D3D3D3','LightGray')
  let i = s:SetNamedColor('#D3D3D3','LightGrey')
  let i = s:SetNamedColor('#90EE90','LightGreen')
  let i = s:SetNamedColor('#FFB6C1','LightPink')
  let i = s:SetNamedColor('#FFA07A','LightSalmon')
  let i = s:SetNamedColor('#20B2AA','LightSeaGreen')
  let i = s:SetNamedColor('#87CEFA','LightSkyBlue')
  let i = s:SetNamedColor('#778899','LightSlateGray')
  let i = s:SetNamedColor('#778899','LightSlateGrey')
  let i = s:SetNamedColor('#B0C4DE','LightSteelBlue')
  let i = s:SetNamedColor('#FFFFE0','LightYellow')
  let i = s:SetNamedColor('#32CD32','LimeGreen')
  let i = s:SetNamedColor('#FAF0E6','Linen')
  let i = s:SetNamedColor('#FF00FF','Magenta')
  let i = s:SetNamedColor('#66CDAA','MediumAquaMarine')
  let i = s:SetNamedColor('#0000CD','MediumBlue')
  let i = s:SetNamedColor('#BA55D3','MediumOrchid')
  let i = s:SetNamedColor('#9370D8','MediumPurple')
  let i = s:SetNamedColor('#3CB371','MediumSeaGreen')
  let i = s:SetNamedColor('#7B68EE','MediumSlateBlue')
  let i = s:SetNamedColor('#00FA9A','MediumSpringGreen')
  let i = s:SetNamedColor('#48D1CC','MediumTurquoise')
  let i = s:SetNamedColor('#C71585','MediumVioletRed')
  let i = s:SetNamedColor('#191970','MidnightBlue')
  let i = s:SetNamedColor('#F5FFFA','MintCream')
  let i = s:SetNamedColor('#FFE4E1','MistyRose')
  let i = s:SetNamedColor('#FFE4B5','Moccasin')
  let i = s:SetNamedColor('#FFDEAD','NavajoWhite')
  let i = s:SetNamedColor('#FDF5E6','OldLace')
  let i = s:SetNamedColor('#6B8E23','OliveDrab')
  let i = s:SetNamedColor('#FF4500','OrangeRed')
  let i = s:SetNamedColor('#DA70D6','Orchid')
  let i = s:SetNamedColor('#EEE8AA','PaleGoldenRod')
  let i = s:SetNamedColor('#98FB98','PaleGreen')
  let i = s:SetNamedColor('#AFEEEE','PaleTurquoise')
  let i = s:SetNamedColor('#D87093','PaleVioletRed')
  let i = s:SetNamedColor('#FFEFD5','PapayaWhip')
  let i = s:SetNamedColor('#FFDAB9','PeachPuff')
  let i = s:SetNamedColor('#CD853F','Peru')
  let i = s:SetNamedColor('#FFC0CB','Pink')
  let i = s:SetNamedColor('#DDA0DD','Plum')
  let i = s:SetNamedColor('#B0E0E6','PowderBlue')
  let i = s:SetNamedColor('#BC8F8F','RosyBrown')
  let i = s:SetNamedColor('#4169E1','RoyalBlue')
  let i = s:SetNamedColor('#8B4513','SaddleBrown')
  let i = s:SetNamedColor('#FA8072','Salmon')
  let i = s:SetNamedColor('#F4A460','SandyBrown')
  let i = s:SetNamedColor('#2E8B57','SeaGreen')
  let i = s:SetNamedColor('#FFF5EE','SeaShell')
  let i = s:SetNamedColor('#A0522D','Sienna')
  let i = s:SetNamedColor('#87CEEB','SkyBlue')
  let i = s:SetNamedColor('#6A5ACD','SlateBlue')
  let i = s:SetNamedColor('#708090','SlateGray')
  let i = s:SetNamedColor('#708090','SlateGrey')
  let i = s:SetNamedColor('#FFFAFA','Snow')
  let i = s:SetNamedColor('#00FF7F','SpringGreen')
  let i = s:SetNamedColor('#4682B4','SteelBlue')
  let i = s:SetNamedColor('#D2B48C','Tan')
  let i = s:SetNamedColor('#D8BFD8','Thistle')
  let i = s:SetNamedColor('#FF6347','Tomato')
  let i = s:SetNamedColor('#40E0D0','Turquoise')
  let i = s:SetNamedColor('#EE82EE','Violet')
  let i = s:SetNamedColor('#F5DEB3','Wheat')
  let i = s:SetNamedColor('#F5F5F5','WhiteSmoke')
  let i = s:SetNamedColor('#9ACD32','YellowGreen')
 
  let i = 1
  while i <= line("$")
    call s:PreviewCSSColorInLine(i)
    let i = i+1
  endwhile
  unlet i
 
  augroup PreviewCSSColor
    autocmd!
    autocmd CursorHold *.css silent call s:PreviewCSSColorInLine('.')
    autocmd CursorHoldI *.css silent call s:PreviewCSSColorInLine('.')
    autocmd InsertLeave *.css silent call s:PreviewCSSColorInLine('.')
  augroup END
endif  " has("gui_running")