Merge 2ab2d9f into 6041f90

Readme.md

@@ -58,9 +58,9 @@ You can optionally check the buffer lengths & stop downloading the image after a
 * PSD
 * TIFF
 * WebP
+* SVG
 
 ##### Upcoming
-* SVG
 * SWF
 
 ##### Credits

lib/types.js

@@ -6,7 +6,7 @@ module.exports = [
   'jpg',
   'png',
   'psd',
-//  'svg',
+  'svg',
   'tiff',
   'webp'
 ];

lib/types/svg.js

@@ -0,0 +1,69 @@
+'use strict';
+
+var svgReg = /<svg[^>]+[^>]*>/;
+function isSVG (buffer) {
+  return svgReg.test(buffer);
+}
+
+var extractorRegExps = {
+  'root': /<svg [^>]+>/,
+  'width': /(^|\s)width\s*=\s*"(.+?)"/i,
+  'height': /(^|\s)height\s*=\s*"(.+?)"/i,
+  'viewbox': /(^|\s)viewbox\s*=\s*"(.+?)"/i
+};
+
+function getRatio (viewbox) {
+  var ratio = 1;
+  if (viewbox && viewbox[2]) {
+    var dim = viewbox[2].split(/\s/g);
+    if (dim.length === 4) {
+      dim = dim.map(function (i) {
+        return parseInt(i, 10);
+      });
+      ratio = (dim[2] - dim[0]) / (dim[3] - dim[1]);
+    }
+  }
+  return ratio;
+}
+
+function parse (buffer) {
+  var body = buffer.toString().replace(/[\r\n\s]+/g, ' ');
+  var section = body.match(extractorRegExps.root);
+  var root = section && section[0];
+  if (root) {
+    var width = root.match(extractorRegExps.width);
+    var height = root.match(extractorRegExps.height);
+    var viewbox = root.match(extractorRegExps.viewbox);
+    var ratio = getRatio(viewbox);
+    return {
+      'width': parseInt(width && width[2], 10) || 0,
+      'height': parseInt(height && height[2], 10) || 0,
+      'ratio': ratio
+    };
+  }
+}
+
+function calculate (buffer) {
+
+  var parsed = parse(buffer);
+  var width = parsed.width;
+  var height = parsed.height;
+  var ratio = parsed.ratio;
+
+  if (width && height) {
+    return { 'width': width, 'height': height };
+  } else {
+    if (width) {
+      return { 'width': width, 'height': Math.floor(width / ratio) };
+    } else if (height) {
+      return { 'width': Math.floor(height * ratio), 'height': height };
+    } else {
+      throw new TypeError('invalid svg');
+    }
+  }
+}
+
+module.exports = {
+  'detect': isSVG,
+  'calculate': calculate
+};