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October 13, 2011 14:29
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Simple parser for CSS color literals, based on Scala parser combinators
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| /* | |
| * Copyright (c) 2011 Untyped Ltd, http://untyped.com | |
| * | |
| * Permission is hereby granted, free of charge, to any person obtaining | |
| * a copy of this software and associated documentation files (the | |
| * "Software"), to deal in the Software without restriction, including | |
| * without limitation the rights to use, copy, modify, merge, publish, | |
| * distribute, sublicense, and/or sell copies of the Software, and to | |
| * permit persons to whom the Software is furnished to do so, subject to | |
| * the following conditions: | |
| * | |
| * The above copyright notice and this permission notice shall be | |
| * included in all copies or substantial portions of the Software. | |
| * | |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | |
| * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | |
| * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE | |
| * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION | |
| * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION | |
| * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. | |
| */ | |
| import java.awt.Color | |
| import java.text.{DecimalFormat, FieldPosition} | |
| import scala.util.parsing.combinator._ | |
| /** | |
| * Simple parser for CSS color literals. Usage: | |
| * | |
| * ColorParser.parseColor("#f00") | |
| * | |
| * Understands the following color formats: | |
| * | |
| * short hex strings e.g. #f00 | |
| * long hex strings e.g. #ff0000 | |
| * rgb function literals e.g. rgb(100, 0, 0) | |
| * rgba function literals e.g. rgba(100, 0, 0, 0.5) | |
| * hsl function literals e.g. hsl(180, 120, 120) | |
| * hsla function literals e.g. hsla(180, 120, 120, 0.5) | |
| * friendly color names e.g. red | |
| * "transparent" keyword | |
| */ | |
| object ColorParser extends RegexParsers { | |
| override def skipWhitespace = true | |
| /** Entry point to the parser. */ | |
| def parseColor(input: String): Option[Color] = | |
| parseAll(color, input.toLowerCase).map(Some(_)).getOrElse(None) | |
| /** Top parser rule */ | |
| def color: Parser[Color] = | |
| longHex | | |
| shortHex | | |
| named | | |
| func | | |
| transparent | |
| def longHex: Parser[Color] = | |
| ("#" ~> doubleHex ~ doubleHex ~ doubleHex) ^^ | |
| { case r ~ g ~ b => new Color(r, g, b) } | |
| def shortHex: Parser[Color] = | |
| ("#" ~> singleHex ~ singleHex ~ singleHex) ^^ | |
| { case r ~ g ~ b => new Color(r, g, b) } | |
| def doubleHex: Parser[Float] = "[0-9a-f]{2}".r ^^ (x => parseHex(x)) | |
| def singleHex: Parser[Float] = "[0-9a-f]".r ^^ (x => parseHex(x + x)) | |
| def parseHex(hex: String): Float = 1.0f * Integer.parseInt(hex, 16) / 255 | |
| def named: Parser[Color] = "[a-z]+".r ^? namedColors | |
| def func: Parser[Color] = | |
| (("rgb(" ~ rgbArg ~ "," ~ rgbArg ~ "," ~ rgbArg ~ ")") ^^ | |
| { case _ ~ r ~ _ ~ g ~ _ ~ b ~ _ => new Color(r, g, b) }) | | |
| (("rgba(" ~ rgbArg ~ "," ~ rgbArg ~ "," ~ rgbArg ~ "," ~ alphaArg ~ ")") ^^ | |
| { case _ ~ r ~ _ ~ g ~ _ ~ b ~ _ ~ a ~ _ => new Color(r, g, b, a) }) | | |
| (("hsl(" ~ angleArg ~ "," ~ percentArg ~ "," ~ percentArg ~ ")") ^^ | |
| { case _ ~ h ~ _ ~ s ~ _ ~ l ~ _ => hslColor(h, s, l, 255) }) | | |
| (("hsla(" ~ angleArg ~ "," ~ percentArg ~ "," ~ percentArg ~ "," ~ alphaArg ~ ")") ^^ | |
| { case _ ~ h ~ _ ~ s ~ _ ~ l ~ _ ~ a ~ _ => hslColor(h, s, l, a) }) | |
| def hslColor(h: Float, s: Float, l: Float, a: Float): Color = { | |
| val base = Color.getHSBColor(h, s, l) | |
| if(a == 1.0f) base else new Color(base.getRed, base.getGreen, base.getBlue, (a*255).toInt) | |
| } | |
| def hslColor(h: Float, s: Float, l: Float, a: Int): Color = { | |
| val base = Color.getHSBColor(h, s, l) | |
| if(a == 255) base else new Color(base.getRed, base.getGreen, base.getBlue, a) | |
| } | |
| def transparent: Parser[Color] = | |
| "transparent" ^^ (x => new Color(0,0,0,0)) | |
| def rgbArg: Parser[Float] = | |
| percentArg | | |
| byteArg | |
| def alphaArg: Parser[Float] = | |
| "-?[0-9]*.?[0-9]+".r ^^ (x => parseFloat(x, 0.0f, 1.0f)) | |
| def percentArg: Parser[Float] = | |
| (("-?[0-9]+".r ~ "%") ^^ { case x ~ "%" => 1.0f * parseInt(x, 10, 0, 100) / 100 }) | |
| def byteArg: Parser[Float] = | |
| ("-?[0-9]+".r ^^ (x => 1.0f * parseInt(x, 10, 0, 255) / 255)) | |
| def angleArg: Parser[Float] = | |
| ("-?[0-9]+".r ^^ (x => 1.0f * parseDegrees(x) / 360)) | |
| def parseInt(str: String, base: Int, min: Int, max: Int): Int = | |
| trimNumber(java.lang.Integer.parseInt(str, base), min, max) | |
| def trimNumber(num: Int, min: Int, max: Int) = math.min(math.max(num, min), max) | |
| def trimNumber(num: Float, min: Float, max: Float) = math.min(math.max(num, min), max) | |
| def parseDegrees(str: String): Int = { | |
| val ans = java.lang.Integer.parseInt(str) % 360 | |
| if(ans < 0) ans + 360 else ans | |
| } | |
| def parseFloat(str: String, min: Float, max: Float): Float = | |
| math.min(math.max(java.lang.Float.parseFloat(str), min), max) | |
| val namedColors: Map[String, Color] = | |
| Map("aliceblue" -> "#f0f8ff", | |
| "antiquewhite" -> "#faebd7", | |
| "aqua" -> "#00ffff", | |
| "aquamarine" -> "#7fffd4", | |
| "azure" -> "#f0ffff", | |
| "beige" -> "#f5f5dc", | |
| "bisque" -> "#ffe4c4", | |
| "black" -> "#000000", | |
| "blanchedalmond" -> "#ffebcd", | |
| "blue" -> "#0000ff", | |
| "blueviolet" -> "#8a2be2", | |
| "brown" -> "#a52a2a", | |
| "burlywood" -> "#deb887", | |
| "cadetblue" -> "#5f9ea0", | |
| "chartreuse" -> "#7fff00", | |
| "chocolate" -> "#d2691e", | |
| "coral" -> "#ff7f50", | |
| "cornflowerblue" -> "#6495ed", | |
| "cornsilk" -> "#fff8dc", | |
| "crimson" -> "#dc143c", | |
| "cyan" -> "#00ffff", | |
| "darkblue" -> "#00008b", | |
| "darkcyan" -> "#008b8b", | |
| "darkgoldenrod" -> "#b8860b", | |
| "darkgray" -> "#a9a9a9", | |
| "darkgrey" -> "#a9a9a9", | |
| "darkgreen" -> "#006400", | |
| "darkkhaki" -> "#bdb76b", | |
| "darkmagenta" -> "#8b008b", | |
| "darkolivegreen" -> "#556b2f", | |
| "darkorange" -> "#ff8c00", | |
| "darkorchid" -> "#9932cc", | |
| "darkred" -> "#8b0000", | |
| "darksalmon" -> "#e9967a", | |
| "darkseagreen" -> "#8fbc8f", | |
| "darkslateblue" -> "#483d8b", | |
| "darkslategray" -> "#2f4f4f", | |
| "darkslategrey" -> "#2f4f4f", | |
| "darkturquoise" -> "#00ced1", | |
| "darkviolet" -> "#9400d3", | |
| "deeppink" -> "#ff1493", | |
| "deepskyblue" -> "#00bfff", | |
| "dimgray" -> "#696969", | |
| "dimgrey" -> "#696969", | |
| "dodgerblue" -> "#1e90ff", | |
| "firebrick" -> "#b22222", | |
| "floralwhite" -> "#fffaf0", | |
| "forestgreen" -> "#228b22", | |
| "fuchsia" -> "#ff00ff", | |
| "gainsboro" -> "#dcdcdc", | |
| "ghostwhite" -> "#f8f8ff", | |
| "gold" -> "#ffd700", | |
| "goldenrod" -> "#daa520", | |
| "gray" -> "#808080", | |
| "grey" -> "#808080", | |
| "green" -> "#008000", | |
| "greenyellow" -> "#adff2f", | |
| "honeydew" -> "#f0fff0", | |
| "hotpink" -> "#ff69b4", | |
| "indianred" -> "#cd5c5c", | |
| "indigo" -> "#4b0082", | |
| "ivory" -> "#fffff0", | |
| "khaki" -> "#f0e68c", | |
| "lavender" -> "#e6e6fa", | |
| "lavenderblush" -> "#fff0f5", | |
| "lawngreen" -> "#7cfc00", | |
| "lemonchiffon" -> "#fffacd", | |
| "lightblue" -> "#add8e6", | |
| "lightcoral" -> "#f08080", | |
| "lightcyan" -> "#e0ffff", | |
| "lightgoldenrodyellow" -> "#fafad2", | |
| "lightgray" -> "#d3d3d3", | |
| "lightgrey" -> "#d3d3d3", | |
| "lightgreen" -> "#90ee90", | |
| "lightpink" -> "#ffb6c1", | |
| "lightsalmon" -> "#ffa07a", | |
| "lightseagreen" -> "#20b2aa", | |
| "lightskyblue" -> "#87cefa", | |
| "lightslategray" -> "#778899", | |
| "lightslategrey" -> "#778899", | |
| "lightsteelblue" -> "#b0c4de", | |
| "lightyellow" -> "#ffffe0", | |
| "lime" -> "#00ff00", | |
| "limegreen" -> "#32cd32", | |
| "linen" -> "#faf0e6", | |
| "magenta" -> "#ff00ff", | |
| "maroon" -> "#800000", | |
| "mediumaquamarine" -> "#66cdaa", | |
| "mediumblue" -> "#0000cd", | |
| "mediumorchid" -> "#ba55d3", | |
| "mediumpurple" -> "#9370d8", | |
| "mediumseagreen" -> "#3cb371", | |
| "mediumslateblue" -> "#7b68ee", | |
| "mediumspringgreen" -> "#00fa9a", | |
| "mediumturquoise" -> "#48d1cc", | |
| "mediumvioletred" -> "#c71585", | |
| "midnightblue" -> "#191970", | |
| "mintcream" -> "#f5fffa", | |
| "mistyrose" -> "#ffe4e1", | |
| "moccasin" -> "#ffe4b5", | |
| "navajowhite" -> "#ffdead", | |
| "navy" -> "#000080", | |
| "oldlace" -> "#fdf5e6", | |
| "olive" -> "#808000", | |
| "olivedrab" -> "#6b8e23", | |
| "orange" -> "#ffa500", | |
| "orangered" -> "#ff4500", | |
| "orchid" -> "#da70d6", | |
| "palegoldenrod" -> "#eee8aa", | |
| "palegreen" -> "#98fb98", | |
| "paleturquoise" -> "#afeeee", | |
| "palevioletred" -> "#d87093", | |
| "papayawhip" -> "#ffefd5", | |
| "peachpuff" -> "#ffdab9", | |
| "peru" -> "#cd853f", | |
| "pink" -> "#ffc0cb", | |
| "plum" -> "#dda0dd", | |
| "powderblue" -> "#b0e0e6", | |
| "purple" -> "#800080", | |
| "red" -> "#ff0000", | |
| "rosybrown" -> "#bc8f8f", | |
| "royalblue" -> "#4169e1", | |
| "saddlebrown" -> "#8b4513", | |
| "salmon" -> "#fa8072", | |
| "sandybrown" -> "#f4a460", | |
| "seagreen" -> "#2e8b57", | |
| "seashell" -> "#fff5ee", | |
| "sienna" -> "#a0522d", | |
| "silver" -> "#c0c0c0", | |
| "skyblue" -> "#87ceeb", | |
| "slateblue" -> "#6a5acd", | |
| "slategray" -> "#708090", | |
| "slategrey" -> "#708090", | |
| "snow" -> "#fffafa", | |
| "springgreen" -> "#00ff7f", | |
| "steelblue" -> "#4682b4", | |
| "tan" -> "#d2b48c", | |
| "teal" -> "#008080", | |
| "thistle" -> "#d8bfd8", | |
| "tomato" -> "#ff6347", | |
| "turquoise" -> "#40e0d0", | |
| "violet" -> "#ee82ee", | |
| "wheat" -> "#f5deb3", | |
| "white" -> "#ffffff", | |
| "whitesmoke" -> "#f5f5f5", | |
| "yellow" -> "#ffff00", | |
| "yellowgreen" -> "#9acd32").map { case (k, v) => k -> parseColor(v).get } | |
| } |
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| /* | |
| * Copyright (c) 2011 Untyped Ltd, http://untyped.com | |
| * | |
| * Permission is hereby granted, free of charge, to any person obtaining | |
| * a copy of this software and associated documentation files (the | |
| * "Software"), to deal in the Software without restriction, including | |
| * without limitation the rights to use, copy, modify, merge, publish, | |
| * distribute, sublicense, and/or sell copies of the Software, and to | |
| * permit persons to whom the Software is furnished to do so, subject to | |
| * the following conditions: | |
| * | |
| * The above copyright notice and this permission notice shall be | |
| * included in all copies or substantial portions of the Software. | |
| * | |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, | |
| * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF | |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND | |
| * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE | |
| * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION | |
| * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION | |
| * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. | |
| */ | |
| import java.awt.Color | |
| import org.scalatest._ | |
| class ColorUtilSuite extends FunSuite with Assertions { | |
| import ColorUtil._ | |
| test("trimNumber") { | |
| expect(1)(trimNumber(0, 1, 3)) | |
| expect(1)(trimNumber(1, 1, 3)) | |
| expect(2)(trimNumber(2, 1, 3)) | |
| expect(3)(trimNumber(3, 1, 3)) | |
| expect(3)(trimNumber(4, 1, 3)) | |
| expect(1.0f)(trimNumber(0.0f, 1.0f, 3.0f)) | |
| expect(1.0f)(trimNumber(1.0f, 1.0f, 3.0f)) | |
| expect(2.0f)(trimNumber(2.0f, 1.0f, 3.0f)) | |
| expect(3.0f)(trimNumber(3.0f, 1.0f, 3.0f)) | |
| expect(3.0f)(trimNumber(4.0f, 1.0f, 3.0f)) | |
| } | |
| test("parseColor - long hex") { | |
| expect(Some(new Color( 0, 0, 0)))(parseColor("#000000")) | |
| expect(Some(new Color(255,255,255)))(parseColor("#ffffff")) | |
| expect(Some(new Color(255,255,255)))(parseColor("#FFFFFF")) | |
| expect(Some(new Color(255,119, 0)))(parseColor("#ff7700")) | |
| } | |
| test("parseColor - short hex") { | |
| expect(Some(new Color( 0, 0, 0)))(parseColor("#000")) | |
| expect(Some(new Color(255,255,255)))(parseColor("#fff")) | |
| expect(Some(new Color(255,255,255)))(parseColor("#FFF")) | |
| expect(Some(new Color(255,119, 0)))(parseColor("#f70")) | |
| } | |
| test("parseColor - named") { | |
| expect(Some(new Color(255, 0, 0)))(parseColor("red")) | |
| expect(Some(new Color(255, 0, 0)))(parseColor("Red")) | |
| expect(Some(new Color(255, 0, 0)))(parseColor("RED")) | |
| } | |
| test("parseColor - transparent") { | |
| expect(Some(new Color(0,0,0,0)))(parseColor("transparent")) | |
| } | |
| test("parseColor - rgb(int,int,int)") { | |
| expect(Some(new Color(255,127, 0)))(parseColor("rgb(255,127,0)")) | |
| expect(Some(new Color(255,127, 0)))(parseColor("RGB(255,127,0)")) | |
| expect(Some(new Color(255,127, 0)))(parseColor("RGB(300,127,-100)")) | |
| } | |
| test("parseColor - rgb(%,%,%)") { | |
| expect(Some(new Color(255,128, 0)))(parseColor("rgb(100%,50%,0%)")) | |
| expect(Some(new Color(255,128, 0)))(parseColor("RGB(100%,50%,0%)")) | |
| expect(Some(new Color(255,128, 0)))(parseColor("RGB(150%,50%,-50%)")) | |
| } | |
| test("parseColor - rgba(int,int,int,float)") { | |
| expect(Some(new Color(255,127, 0,255)))(parseColor("rgba(255,127,0,1)")) | |
| expect(Some(new Color(255,127, 0, 0)))(parseColor("rgba(255,127,0,0.0)")) | |
| expect(Some(new Color(255,127, 0,128)))(parseColor("RGBA(255,127,0,.5)")) | |
| expect(Some(new Color(255,127, 0, 0)))(parseColor("rgba(255,127,0,-0.5)")) | |
| expect(Some(new Color(0,0,0,0)))(parseColor("rgba(0,0,0,0)")) | |
| } | |
| test("parseColor - rgba(%,%,%,float)") { | |
| expect(Some(new Color(255,128, 0,255)))(parseColor("rgba(100%,50%,0%,1)")) | |
| expect(Some(new Color(255,128, 0, 0)))(parseColor("RGBA(100%,50%,0%,0.0)")) | |
| expect(Some(new Color(255,128, 0,128)))(parseColor("RGBA(150%,50%,-50%,.5)")) | |
| expect(Some(new Color(255,128, 0, 0)))(parseColor("RGBA(100%,50%,0%,-0.5)")) | |
| } | |
| test("parseColor - hsl(angle,%,%)") { | |
| expect(Some(new Color(255, 0, 0)))(parseColor("hsl(0,100%,100%)")) | |
| expect(Some(new Color( 0,255, 0)))(parseColor("hsl(120,100%,100%)")) | |
| expect(Some(new Color( 0,255, 0)))(parseColor("HSL(-240,100%,100%)")) | |
| expect(Some(new Color( 0,255, 0)))(parseColor("HSL(480,100%,100%)")) | |
| } | |
| } |
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