5 files changed, 230 insertions, 230 deletions

diff --git a/lib/output/assets-inliner.js b/lib/output/assets-inliner.js
index 9733505..b5d076e 100644
--- a/lib/output/assets-inliner.js
+++ b/lib/output/assets-inliner.js
@@ -2,7 +2,7 @@ var util = require('util');
 var path = require('path');
 var crc = require('crc');
 
-var FolderOutput = require('./folder');
+var FolderOutput = require('./folder')();
 var Promise = require('../utils/promise');
 var fs = require('../utils/fs');
 var imagesUtil = require('../utils/images');
@@ -11,123 +11,126 @@ var location = require('../utils/location');
 var DEFAULT_ASSETS_FOLDER = 'assets';
 
 /*
-Utility mixin to inline all the assets in a book:
+Mixin to inline all the assets in a book:
     - Outline <svg> tags
     - Download remote images
     - Convert .svg images as png
 */
 
-function AssetsInliner() {
-    FolderOutput.apply(this, arguments);
+module.exports = function assetsInliner(Base) {
+    Base = Base || FolderOutput;
 
-    // Map of svg already converted
-    this.svgs = {};
-    this.inlineSvgs = {};
+    function AssetsInliner() {
+        Base.apply(this, arguments);
 
-    // Map of images already downloaded
-    this.downloaded = {};
-}
-util.inherits(AssetsInliner, FolderOutput);
+        // Map of svg already converted
+        this.svgs = {};
+        this.inlineSvgs = {};
 
-// Output a SVG buffer as a file
-AssetsInliner.prototype.onOutputSVG = function(page, svg) {
-    this.log.debug.ln('output svg from', page.path);
+        // Map of images already downloaded
+        this.downloaded = {};
+    }
+    util.inherits(AssetsInliner, Base);
 
-    // Convert svg buffer to a png file
-    return this.convertSVGBuffer(svg)
+    // Output a SVG buffer as a file
+    AssetsInliner.prototype.onOutputSVG = function(page, svg) {
+        this.log.debug.ln('output svg from', page.path);
 
-        // Return relative path from the page
-        .then(function(filename) {
-            return page.relative('/' + filename);
-        });
-};
+        // Convert svg buffer to a png file
+        return this.convertSVGBuffer(svg)
 
+            // Return relative path from the page
+            .then(function(filename) {
+                return page.relative('/' + filename);
+            });
+    };
 
-// Output an image as a file
-AssetsInliner.prototype.onOutputImage = function(page, src) {
-    var that = this;
 
-    return Promise()
+    // Output an image as a file
+    AssetsInliner.prototype.onOutputImage = function(page, src) {
+        var that = this;
 
-    // Download file if external
-    .then(function() {
-        if (!location.isExternal(src)) return;
+        return Promise()
 
-        return that.downloadAsset(src)
-        .then(function(_asset) {
-            src = '/' + _asset;
-        });
+        // Download file if external
+        .then(function() {
+            if (!location.isExternal(src)) return;
 
-    })
-    .then(function() {
-        if (path.extname(src).toLowerCase() != '.svg') {
-            return src;
-        }
+            return that.downloadAsset(src)
+            .then(function(_asset) {
+                src = '/' + _asset;
+            });
 
-        // Convert SVG to PNG
-        return that.convertSVGFile(that.resolveForPage(page, src));
-    })
+        })
+        .then(function() {
+            if (path.extname(src).toLowerCase() != '.svg') {
+                return src;
+            }
 
-    // Return relative path from the page
-    .then(function(filename) {
-        return page.relative('/' + filename);
-    });
-};
+            // Convert SVG to PNG
+            return that.convertSVGFile(that.resolveForPage(page, src));
+        })
 
-// 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]);
+        // Return relative path from the page
+        .then(function(filename) {
+            return page.relative('/' + filename);
+        });
+    };
 
-    var that = this;
-    var ext = path.extname(src);
-    var hash = crc.crc32(src).toString(16);
+    // 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]);
 
-    // Create new file
-    return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + ext)
-    .then(function(filename) {
-        that.downloaded[src] = filename;
+        var that = this;
+        var ext = path.extname(src);
+        var hash = crc.crc32(src).toString(16);
 
-        that.log.debug.ln('downloading asset', src);
-        return fs.download(src, that.resolve(filename))
-        .thenResolve(filename);
-    });
-};
+        // Create new file
+        return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + ext)
+        .then(function(filename) {
+            that.downloaded[src] = 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]);
+            that.log.debug.ln('downloading asset', src);
+            return fs.download(src, that.resolve(filename))
+            .thenResolve(filename);
+        });
+    };
 
-    var that = this;
-    var hash = crc.crc32(src).toString(16);
+    // 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]);
 
-    // Create new file
-    return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + '.png')
-    .then(function(filename) {
-        that.svgs[src] = filename;
+        var that = this;
+        var hash = crc.crc32(src).toString(16);
 
-        return imagesUtil.convertSVGToPNG(src, that.resolve(filename))
-        .thenResolve(filename);
-    });
-};
+        // Create new file
+        return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + '.png')
+        .then(function(filename) {
+            that.svgs[src] = 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);
+            return imagesUtil.convertSVGToPNG(src, that.resolve(filename))
+            .thenResolve(filename);
+        });
+    };
 
-    // Already converted?
-    if (this.inlineSvgs[hash]) return Promise(this.inlineSvgs[hash]);
+    // 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);
 
-    return this.createNewFile(DEFAULT_ASSETS_FOLDER, hash + '.png')
-    .then(function(filename) {
-        that.inlineSvgs[hash] = filename;
+        // Already converted?
+        if (this.inlineSvgs[hash]) return Promise(this.inlineSvgs[hash]);
 
-        return imagesUtil.convertSVGBufferToPNG(buf, that.resolve(filename))
-        .thenResolve(filename);
-    });
-};
+        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;
+    return AssetsInliner;
+};
diff --git a/lib/output/conrefs.js b/lib/output/conrefs.js
index c91885e..f1cd123 100644
--- a/lib/output/conrefs.js
+++ b/lib/output/conrefs.js
@@ -1,60 +1,68 @@
 var path = require('path');
+var util = require('util');
 
-var Output = require('./base');
+var FolderOutput = require('./folder')();
 var Git = require('../utils/git');
 var fs = require('../utils/fs');
 var pathUtil = require('../utils/path');
 
 /*
-Middleware for output to resolve git conrefs
+Mixin for output to resolve git conrefs
 */
 
-var ConrefsLoader = Output.createMixin(function() {
-    this.git = new Git();
-});
-
-// Read a template by its source URL
-ConrefsLoader.prototype.onGetTemplate = function(sourceURL) {
-    var that = this;
-
-    return this.git.resolve(sourceURL)
-    .then(function(filepath) {
-        // Is local file
-        if (!filepath) {
-            filepath = that.book.resolve(sourceURL);
-        } else {
-            that.book.log.debug.ln('resolve from git', sourceURL, 'to', filepath);
-        }
+module.exports = function conrefsLoader(Base) {
+    Base = Base || FolderOutput;
 
-        //  Read file from absolute path
-        return fs.readFile(filepath)
-        .then(function(source) {
-            return {
-                src: source.toString('utf8'),
-                path: filepath
-            };
-        });
-    });
-};
+    function ConrefsLoader() {
+        Base.apply(this, arguments);
 
-// Generate a source URL for a template
-ConrefsLoader.prototype.onResolveTemplate = function(from, to) {
-    // If origin is in the book, we enforce result file to be in the book
-    if (this.book.isInBook(from)) {
-        return this.book.resolve(
-            this.book.relative(path.dirname(from)),
-            to
-        );
+        this.git = new Git();
     }
+    util.inherits(ConrefsLoader, Base);
 
-    // If origin is in a git repository, we resolve file in the git repository
-    var gitRoot = this.git.resolveRoot(from);
-    if (gitRoot) {
-        return pathUtil.resolveInRoot(gitRoot, to);
-    }
+    // Read a template by its source URL
+    ConrefsLoader.prototype.onGetTemplate = function(sourceURL) {
+        var that = this;
 
-    // If origin is not in the book (include from a git content ref)
-    return path.resolve(path.dirname(from), to);
-};
+        return this.git.resolve(sourceURL)
+        .then(function(filepath) {
+            // Is local file
+            if (!filepath) {
+                filepath = that.book.resolve(sourceURL);
+            } else {
+                that.book.log.debug.ln('resolve from git', sourceURL, 'to', filepath);
+            }
+
+            //  Read file from absolute path
+            return fs.readFile(filepath)
+            .then(function(source) {
+                return {
+                    src: source.toString('utf8'),
+                    path: filepath
+                };
+            });
+        });
+    };
 
-module.exports = ConrefsLoader;
+    // Generate a source URL for a template
+    ConrefsLoader.prototype.onResolveTemplate = function(from, to) {
+        // If origin is in the book, we enforce result file to be in the book
+        if (this.book.isInBook(from)) {
+            return this.book.resolve(
+                this.book.relative(path.dirname(from)),
+                to
+            );
+        }
+
+        // If origin is in a git repository, we resolve file in the git repository
+        var gitRoot = this.git.resolveRoot(from);
+        if (gitRoot) {
+            return pathUtil.resolveInRoot(gitRoot, to);
+        }
+
+        // If origin is not in the book (include from a git content ref)
+        return path.resolve(path.dirname(from), to);
+    };
+
+    return ConrefsLoader;
+};
diff --git a/lib/output/folder.js b/lib/output/folder.js
index 90a3351..9964ecd 100644
--- a/lib/output/folder.js
+++ b/lib/output/folder.js
@@ -12,104 +12,106 @@ This output requires the native fs module to output
 book as a directory (mapping assets and pages)
 */
 
-function FolderOutput() {
-    Output.apply(this, arguments);
-}
-util.inherits(FolderOutput, Output);
-
-// Copy an asset file (non-parsable), ex: images, etc
-FolderOutput.prototype.onAsset = function(filename) {
-    return this.copyFile(
-        this.book.resolve(filename),
-        filename
-    );
-};
+module.exports = function folderOutput(Base) {
+    Base = Base || Output;
 
-// Prepare the generation by creating the output folder
-FolderOutput.prototype.prepare = function() {
-    return fs.mkdirp(this.root());
-};
+    function FolderOutput() {
+        Base.apply(this, arguments);
+    }
+    util.inherits(FolderOutput, Base);
 
+    // Copy an asset file (non-parsable), ex: images, etc
+    FolderOutput.prototype.onAsset = function(filename) {
+        return this.copyFile(
+            this.book.resolve(filename),
+            filename
+        );
+    };
 
-// ----- Utility methods -----
+    // Prepare the generation by creating the output folder
+    FolderOutput.prototype.prepare = function() {
+        return fs.mkdirp(this.root());
+    };
 
-// Return path to the root folder
-FolderOutput.prototype.root = function() {
-    return path.resolve(process.cwd(), this.book.config.get('output'));
-};
 
-// Resolve a file in the output directory
-FolderOutput.prototype.resolve = function(filename) {
-    return pathUtil.resolveInRoot.apply(null, [this.root()].concat(_.toArray(arguments)));
-};
+    // ----- Utility methods -----
 
-// Resolve a file path from a page (in the output folder)
-FolderOutput.prototype.resolveForPage = function(page, filename) {
-    var abs = page.resolveLocal(filename);
-    return this.resolve(abs);
-};
+    // Return path to the root folder
+    FolderOutput.prototype.root = function() {
+        return path.resolve(process.cwd(), this.book.config.get('output'));
+    };
 
+    // Resolve a file in the output directory
+    FolderOutput.prototype.resolve = function(filename) {
+        return pathUtil.resolveInRoot.apply(null, [this.root()].concat(_.toArray(arguments)));
+    };
 
-// Copy a file to the output
-FolderOutput.prototype.copyFile = function(from, to) {
-    var that = this;
+    // Resolve a file path from a page (in the output folder)
+    FolderOutput.prototype.resolveForPage = function(page, filename) {
+        var abs = page.resolveLocal(filename);
+        return this.resolve(abs);
+    };
 
-    return Promise()
-    .then(function() {
-        to = that.resolve(to);
 
-        return fs.copy(from, to);
-    });
-};
+    // Copy a file to the output
+    FolderOutput.prototype.copyFile = function(from, to) {
+        var that = this;
 
-// Write a file/buffer to the output folder
-FolderOutput.prototype.writeFile = function(filename, buf) {
-    var that = this;
+        return Promise()
+        .then(function() {
+            to = that.resolve(to);
 
-    return Promise()
-    .then(function() {
-        filename = that.resolve(filename);
-        var folder = path.dirname(filename);
+            return fs.copy(from, to);
+        });
+    };
 
-        // Ensure fodler exists
-        return fs.mkdirp(folder);
-    })
+    // Write a file/buffer to the output folder
+    FolderOutput.prototype.writeFile = function(filename, buf) {
+        var that = this;
 
-    // Write the file
-    .then(function() {
-        return fs.writeFile(filename, buf);
-    });
-};
+        return Promise()
+        .then(function() {
+            filename = that.resolve(filename);
+            var folder = path.dirname(filename);
 
-// Return true if a file exists in the output folder
-FolderOutput.prototype.hasFile = function(filename) {
-    var that = this;
+            // Ensure fodler exists
+            return fs.mkdirp(folder);
+        })
 
-    return Promise()
-    .then(function() {
-        return fs.exists(that.resolve(filename));
-    });
-};
+        // Write the file
+        .then(function() {
+            return fs.writeFile(filename, buf);
+        });
+    };
 
+    // Return true if a file exists in the output folder
+    FolderOutput.prototype.hasFile = function(filename) {
+        var that = this;
 
-// Create a new unique file
-// Returns its filename
-FolderOutput.prototype.createNewFile = function(base, filename) {
-    var that = this;
+        return Promise()
+        .then(function() {
+            return fs.exists(that.resolve(filename));
+        });
+    };
 
-    if (!filename) {
-        filename = path.basename(filename);
-        base = path.dirname(base);
-    }
+    // Create a new unique file
+    // Returns its filename
+    FolderOutput.prototype.createNewFile = function(base, filename) {
+        var that = this;
 
-    return fs.uniqueFilename(this.resolve(base), filename)
-        .then(function(out) {
-            out = path.join(base, out);
+        if (!filename) {
+            filename = path.basename(filename);
+            base = path.dirname(base);
+        }
 
-            return fs.ensure(that.resolve(out))
-                .thenResolve(out);
-        });
-};
+        return fs.uniqueFilename(this.resolve(base), filename)
+            .then(function(out) {
+                out = path.join(base, out);
 
+                return fs.ensure(that.resolve(out))
+                    .thenResolve(out);
+            });
+    };
 
-module.exports = FolderOutput;
+    return FolderOutput;
+};
diff --git a/lib/output/json.js b/lib/output/json.js
index f146023..913bc2b 100644
--- a/lib/output/json.js
+++ b/lib/output/json.js
@@ -1,14 +1,8 @@
-var util = require('util');
-var FolderOutput = require('./folder');
-var ConrefsLoader = require('./conrefs');
 var gitbook = require('../gitbook');
+var conrefsLoader = require('./conrefs');
 
-function JSONOutput() {
-    FolderOutput.apply(this, arguments);
-    ConrefsLoader.apply(this);
-}
-util.inherits(JSONOutput, FolderOutput);
-util.inherits(JSONOutput, ConrefsLoader);
+
+var JSONOutput = conrefsLoader();
 
 JSONOutput.prototype.name = 'json';
 
diff --git a/lib/output/website/index.js b/lib/output/website/index.js
index fc9bc6b..6166ccc 100644
--- a/lib/output/website/index.js
+++ b/lib/output/website/index.js
@@ -1,15 +1,8 @@
-var util = require('util');
-var FolderOutput = require('../folder');
-var ConrefsLoader = require('../conrefs');
+var conrefsLoader = require('../conrefs');
 
 var Theme = require('./theme');
 
-function WebsiteOutput() {
-    FolderOutput.apply(this, arguments);
-    ConrefsLoader.apply(this);
-}
-util.inherits(WebsiteOutput, FolderOutput);
-util.inherits(WebsiteOutput, ConrefsLoader);
+var WebsiteOutput = conrefsLoader();
 
 WebsiteOutput.prototype.name = 'website';