1 files changed, 73 insertions, 22 deletions

diff --git a/lib/output/assets-inliner.js b/lib/output/assets-inliner.js
index 2156bef..fb348b4 100644
--- a/lib/output/assets-inliner.js
+++ b/lib/output/assets-inliner.js
@@ -1,6 +1,6 @@
-var _ = require('lodash');
 var util = require('util');
 var path = require('path');
+var crc = require('crc');
 
 var FolderOutput = require('./folder');
 var Promise = require('../utils/promise');
@@ -13,52 +13,50 @@ var DEFAULT_ASSETS_FOLDER = 'assets';
 /*
 Utility mixin to inline all the assets in a book:
     - Outline <svg> tags
-    - Convert svg images as png
     - Download remote images
+    - Convert .svg images as png
 */
 
 function AssetsInliner() {
     FolderOutput.apply(this, arguments);
+
+    // Map of svg already converted
+    this.svgs = {};
+    this.inlineSvgs = {};
+
+    // Map of images already downloaded
+    this.downloaded = {};
 }
 util.inherits(AssetsInliner, FolderOutput);
 
 // Output a SVG buffer as a file
 AssetsInliner.prototype.onOutputSVG = function(page, svg) {
     this.log.debug.ln('output svg from', page.path);
-    var filename = _.uniqueId('svg_') + '.png';
 
     // Convert svg buffer to a png file
-    return imagesUtil.convertSVGBufferToPNG(svg, this.resolve(filename))
+    return this.convertSVGBuffer(svg)
 
         // Return relative path from the page
-        .thenResolve(function() {
+        .then(function(filename) {
             return page.relative('/' + filename);
         });
 };
 
+
 // Output an image as a file
 AssetsInliner.prototype.onOutputImage = function(page, src) {
     var that = this;
-    var isSVG = false;
-    var ext = path.extname(src).toLowerCase();
-    if (ext == '.svg') {
-        isSVG = false;
-        ext = '.png';
-    }
 
     return Promise()
 
-    // Allocate a new file
-    .then(function() {
-
-        return that.
-    })
-
     // Download file if external
     .then(function() {
         if (!location.isExternal(src)) return;
 
-        return fs.download(src, )
+        return that.downloadAsset(src)
+        .then(function(_asset) {
+            src = '/' + _asset;
+        });
 
     })
     .then(function() {
@@ -67,16 +65,69 @@ AssetsInliner.prototype.onOutputImage = function(page, src) {
         }
 
         // Convert SVG to PNG
-        var filename = _.uniqueId('svg_') + '.png';
-        return imagesUtil.convertSVGToPNG(page.resolve(src), this.resolve(filename))
-            .thenResolve('/' + filename);
+        return that.convertSVGFile(page.resolve(src));
     })
 
     // Return relative path from the page
-    .thenResolve(function(filename) {
+    .then(function(filename) {
         return page.relative('/' + filename);
     });
 };
 
+// Download an asset if not already download; returns the output file
+AssetsInliner.prototype.downloadAsset = function(src) {
+    if (this.downloaded[src]) return Promise(this.downloaded[src]);
+
+    var that = this;
+    var ext = path.extname(src);
+    var hash = crc.crc32(src).toString(16);
+
+    // Create new file
+    return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + ext)
+    .then(function(filename) {
+        that.downloaded[src] = filename;
+
+        that.log.debug.ln('downloading asset', src);
+        return fs.download(src, filename)
+        .thenResolve(filename);
+    });
+};
+
+// Convert a .svg into an .png
+// Return the output filename for the .png
+AssetsInliner.prototype.convertSVGFile = function(src) {
+    if (this.svgs[src]) return Promise(this.svgs[src]);
+
+    var that = this;
+    var hash = crc.crc32(src).toString(16);
+
+    // Create new file
+    return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + '.png')
+    .then(function(filename) {
+        that.svgs[src] = filename;
+
+        return imagesUtil.convertSVGToPNG(src, that.resolve(filename))
+        .thenResolve(filename);
+    });
+};
+
+// Convert an inline svg into an .png
+// Return the output filename for the .png
+AssetsInliner.prototype.convertSVGBuffer = function(buf) {
+    var that = this;
+    var hash = crc.crc32(buf).toString(16);
+
+    // Already converted?
+    if (this.inlineSvgs[hash]) return Promise(this.inlineSvgs[hash]);
+
+    return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + '.png')
+    .then(function(filename) {
+        that.inlineSvgs[hash] = filename;
+
+        return imagesUtil.convertSVGBufferToPNG(buf, that.resolve(filename))
+        .thenResolve(filename);
+    });
+};
+
 
 module.exports = AssetsInliner;