Add code to build crafting trees

src/coffee/models/crafting/inventory_node.coffee

@@ -0,0 +1,47 @@
+###
+Crafting Guide - crafting_plan_node.coffee
+
+Copyright (c) 2015 by Redwood Labs
+All rights reserved.
+###
+
+CraftingNode = require './crafting_node'
+ItemNode     = require './item_node'
+
+########################################################################################################################
+
+module.exports = class InventoryNode extends CraftingNode
+
+    constructor: (options={})->
+        if not options.inventory? then throw new Error 'options.inventory is required'
+        super options
+
+        @inventory = options.inventory
+
+    # CraftingNode Overrides #######################################################################
+
+    _createChildren: (result=[])->
+        @inventory.each (stack)=>
+            item = @modPack.findItem stack.itemSlug
+            if not item? then throw new Error "Could not find an item for slug: #{stack.itemSlug}"
+            result.push new ItemNode modPack:@modPack, item:item
+        return result
+
+    _checkCompleteness: ->
+        for child in @children
+            return false unless child.isComplete
+        return true
+
+    _checkValidity: ->
+        for child in @children
+            return false unless child.isValid
+
+    # Object Overrides #############################################################################
+
+    toString: (indent='')->
+        completeText = if @complete then 'complete' else 'incomplete'
+        parts = ["#{indent}#{@completeText} InventoryNode for #{@inventory}"]
+        nextIndent = indent + '    '
+        for child in @children
+            parts.push child.toString nextIndent
+        return parts.join '\n'