Allow loading fonts from Buffers in addition to filenames

lib/font.coffee

@@ -6,24 +6,32 @@ By Devon Govett
 TTFFont = require './font/ttf'
 AFMFont = require './font/afm'
 Subset = require './font/subset'
-zlib = require 'zlib'
+fs = require 'fs'
 
 class PDFFont
-  constructor: (@document, @filename, @family, @id) ->
+  constructor: (@document, src, family, @id) ->    
     @ref = @document.ref()
-    
-    if @filename in @_standardFonts
-      @isAFM = true
-      @font = AFMFont.open __dirname + "/font/data/#{@filename}.afm"
-      @registerAFM()
+    if typeof src is 'string'
+      if src of STANDARD_FONTS
+        @isAFM = true
+        @font = AFMFont.open __dirname + "/font/data/#{@filename}.afm"
+        @registerAFM()
+
+      else if /\.(ttf|ttc)$/i.test src
+        @font = TTFFont.open src, family
+        @subset = new Subset @font
+        @registerTTF()
       
-    else if /\.(ttf|ttc)$/i.test @filename
-      @font = TTFFont.open @filename, @family
-      @subset = new Subset @font
-      @registerTTF()
-      
-    else if /\.dfont$/i.test @filename
-      @font = TTFFont.fromDFont @filename, @family
+      else if /\.dfont$/i.test src
+        @font = TTFFont.fromDFont src, family
+        @subset = new Subset @font
+        @registerTTF()
+        
+      else
+        throw new Error 'Not a supported font format or standard PDF font.'
+        
+    else if Buffer.isBuffer(src)
+      @font = TTFFont.fromBuffer src, family
       @subset = new Subset @font
       @registerTTF()
       
@@ -84,7 +92,7 @@ class PDFFont
     throw new Error 'No unicode cmap for font' if not @font.cmap.unicode
       
   embedTTF: ->
-    data = @subset.encode()    
+    data = @subset.encode()
     fontfile = @document.ref()
     fontfile.write data
     

lib/font/ttf.coffee

@@ -22,7 +22,25 @@ class TTFFont
   @fromDFont: (filename, family) ->
     dfont = DFont.open(filename)
     new TTFFont dfont.getNamedFont(family)
-  
+    
+  @fromBuffer: (buffer, family) ->
+    try
+      ttf = new TTFFont buffer, family
+    
+      # check some tables to make sure this is valid
+      unless ttf.head.exists and ttf.name.exists and ttf.cmap.exists
+        # if not, try a DFont
+        dfont = new DFont buffer
+        ttf = new TTFFont dfont.getNamedFont(family)
+        
+        # check again after dfont
+        unless ttf.head.exists and ttf.name.exists and ttf.cmap.exists
+          throw new Error 'Invalid TTF file in DFont'
+      
+      return ttf
+    catch e
+      throw new Error 'Unknown font format in buffer: ' + e.message
+        
   constructor: (@rawData, name) ->
     data = @contents = new Data(rawData)
     

lib/mixins/fonts.coffee

@@ -15,25 +15,41 @@ module.exports =
     # Set the default font
     @font 'Helvetica'
     
-  font: (filename, family, size) ->
+  font: (src, family, size) ->
     if typeof family is 'number'
       size = family
       family = null
     
-    if @_registeredFonts[filename]
-      {filename, family} = @_registeredFonts[filename]
+    # check registered fonts if src is a string
+    if typeof src is 'string' and @_registeredFonts[src]
+      cacheKey = src
+      {src, family} = @_registeredFonts[src]
+    else
+      cacheKey = family or src
+      cacheKey = null unless typeof cacheKey is 'string'
     
     @fontSize size if size?  
-    family ?= filename
     
-    if @_fontFamilies[family]
-      @_font = @_fontFamilies[family]
+    # fast path: check if the font is already in the PDF
+    if font = @_fontFamilies[cacheKey]
+      @_font = font
       return this
       
+    # load the font
     id = 'F' + (++@_fontCount)
-    @_font = new PDFFont(this, filename, family, id)
-    @_fontFamilies[family] = @_font
+    @_font = new PDFFont(this, src, family, id)
     
+    # check for existing font familes with the same name already in the PDF
+    # useful if the font was passed as a buffer
+    if font = @_fontFamilies[@_font.name]
+      @_font = font
+      return this
+      
+    # save the font for reuse later
+    if cacheKey
+      @_fontFamilies[cacheKey] = @_font
+      
+    @_fontFamilies[@_font.name] = @_font
     return this
     
   fontSize: (@_fontSize) ->
@@ -42,9 +58,9 @@ module.exports =
   currentLineHeight: (includeGap = false) ->
     @_font.lineHeight @_fontSize, includeGap
     
-  registerFont: (name, path, family) ->
+  registerFont: (name, src, family) ->
     @_registeredFonts[name] = 
-      filename: path
+      src: src
       family: family
       
     return this