# Observe collection, (changes) =>
#   for key, change of changes
#     change.name

class Observe
  constructor: (@collection, root, callback, curr=null, path = null)->
    curr = curr or root
    throw new Error "Observe: Object missing." if not root
    if typeof callback isnt "function"
      throw new Error "Observe: Callback should be a function."
    if not not curr and curr.constructor is Array
      base = path
      for item, key in curr
        if typeof item is "object"
          new_path = "#{base or ''}[#{key}]"
          new Observe @collection, root, callback, item, new_path
          new_path = ""

    if not not curr and curr.constructor is Object
      base = path
      for key, item of curr
        # if item.constructor.name is "Object"
        if typeof item is "object"
          new_path = "#{base}.#{key}" if base
          new_path = "#{key}" unless base
          new Observe @collection, root, callback, item, new_path
          new_path = ""


    if not not curr and curr.constructor is Array
      base = path
      Object.observe curr, (changes) =>
        result = {}
        original = {}

        changes.forEach (change,i) =>
          index_or_name = if change.index>-1 then change.index else change.name
          new_path = "#{base or ''}[#{index_or_name}]"
          part =
            collection: @collection
            path: new_path
            base: base || ''
            value : change.object[change.index] or
                    change.object[change.name] or
                    change.object
            # json : JSON.stringify(change.object)
          # if change.type is "add" and typeof part.value is "object"

          is_add = change.addedCount > 0 or change.type is "add"
          if typeof part.value is "object" and is_add
            new Observe @collection, root, callback, part.value, part.path
            new_path = ""
          result[i] = part
          original[i] = change
        callback result, original
    else if not not curr and curr.constructor is Object
      base = path
      Object.observe curr, (changes)=>
        result = {}
        original = {}

        changes.forEach (change,i) =>
          new_path = "#{base}.#{change.name}" if base
          new_path = "#{change.name}" unless base

          part =
            collection: @collection
            path: new_path
            base: base || ''
            value : change.object[change.name]

          is_add = change.type is "add" or change.addedCount > 0
          if typeof part.value is "object" and is_add
            new Observe @collection, root, callback, part.value, part.path
            new_path = ""
          result[i] = part
          original[i] = change
        callback result, original