#
# Author:: John Keiser (<jkeiser@opscode.com>)
# Author:: Ho-Sheng Hsiao (<hosh@opscode.com>)
# Copyright:: Copyright (c) 2012 Opscode, Inc.
# License:: Apache License, Version 2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

require 'chef_fs/file_system/file_system_entry'
require 'chef/cookbook/cookbook_version_loader'

module ChefFS
  module FileSystem
    # ChefRepositoryFileSystemEntry works just like FileSystemEntry,
    # except can inflate Chef objects
    class ChefRepositoryFileSystemEntry < FileSystemEntry
      def initialize(name, parent, file_path = nil, data_handler = nil)
        super(name, parent, file_path)
        @data_handler = data_handler
      end

      def chefignore
        nil
      end

      def ignore_empty_directories?
        parent.ignore_empty_directories?
      end

      def data_handler
        @data_handler || parent.data_handler
      end

      def chef_object
        begin
          if parent.path == '/cookbooks'
            loader = Chef::Cookbook::CookbookVersionLoader.new(file_path, parent.chefignore)
            # We need the canonical cookbook name if we are using versioned cookbooks, but we don't
            # want to spend a lot of time adding code to the main Chef libraries
            if Chef::Config[:versioned_cookbooks]

              _canonical_name = canonical_cookbook_name(File.basename(file_path))
              fail "When versioned_cookbooks mode is on, cookbook #{file_path} must match format <cookbook_name>-x.y.z"  unless _canonical_name

              # KLUDGE: We shouldn't have to use instance_variable_set
              loader.instance_variable_set(:@cookbook_name, _canonical_name)
            end

            loader.load_cookbooks
            return loader.cookbook_version
          end

          # Otherwise, inflate the file using the chosen JSON class (if any)
          return data_handler.chef_object(JSON.parse(read, :create_additions => false))
        rescue
          Chef::Log.error("Could not read #{path_for_printing} into a Chef object: #{$!}")
        end
        nil
      end

      # Exposed as a class method so that it can be used elsewhere
      def self.canonical_cookbook_name(entry_name)
        name_match = ChefFS::FileSystem::CookbookDir::VALID_VERSIONED_COOKBOOK_NAME.match(entry_name)
        return nil if name_match.nil?
        return name_match[1]
      end

      def canonical_cookbook_name(entry_name)
        self.class.canonical_cookbook_name(entry_name)
      end

      def children
        Dir.entries(file_path).sort.
            select { |entry| entry != '.' && entry != '..' }.
            map { |entry| ChefRepositoryFileSystemEntry.new(entry, self) }.
            select { |entry| !ignored?(entry) }
      end

      private

      def ignored?(child_entry)
        if child_entry.dir?
          # empty cookbooks and cookbook directories are ignored
          if ignore_empty_directories? && child_entry.children.size == 0
            return true
          end
        else
          ignorer = parent
          begin
            if ignorer.chefignore
              # Grab the path from entry to child
              path_to_child = child_entry.name
              child = self
              while child.parent != ignorer
                path_to_child = PathUtils.join(child.name, path_to_child)
                child = child.parent
              end
              # Check whether that relative path is ignored
              return ignorer.chefignore.ignored?(path_to_child)
            end
            ignorer = ignorer.parent
          end while ignorer
        end
      end

    end
  end
end