#
#--
# Copyright (c) 2006-2007, Nicolas Modryzk and John Mettraux, OpenWFE.org
# All rights reserved.
# 
# Redistribution and use in source and binary forms, with or without 
# modification, are permitted provided that the following conditions are met:
# 
# . Redistributions of source code must retain the above copyright notice, this
#   list of conditions and the following disclaimer.  
# 
# . Redistributions in binary form must reproduce the above copyright notice, 
#   this list of conditions and the following disclaimer in the documentation 
#   and/or other materials provided with the distribution.
# 
# . Neither the name of the "OpenWFE" nor the names of its contributors may be
#   used to endorse or promote products derived from this software without
#   specific prior written permission.
# 
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
# POSSIBILITY OF SUCH DAMAGE.
#++
#
# $Id: definitions.rb 2725 2006-06-02 13:26:32Z jmettraux $
#

#
# "made in Japan"
#
# Nicolas Modrzyk at openwfe.org
# John Mettraux at openwfe.org
#

require 'yaml'
require 'fileutils'

require 'openwfe/utils'
require 'openwfe/service'

require 'openwfe/expressions/flowexpression'
require 'openwfe/expressions/raw_xml'
    #
    # making sure classes in those files are loaded
    # before their yaml persistence is tuned
    # (else the reopening of the class is interpreted as
    # a definition of the class...)


module OpenWFE
    
    
    #
    # yaml expression storage
    #
    class YamlFileStorage  
        include ServiceMixin
        
        attr_accessor :basepath
        
        def initialize (service_name, application_context, path)
            service_init(service_name, application_context)
            @basepath = path
            FileUtils.makedirs @basepath 
        end
        
        def []= (id, object)
            
            fei_path = compute_file_path(id)
            fei_parent_path = File.dirname(fei_path)
            
            FileUtils.makedirs(fei_parent_path) \
            if not File.exist?(fei_parent_path)
                
                fd = IO.sysopen(fei_path , "w+")
                io = IO.open(fd , "w+")
                
                data = YAML.dump(object)
                
                io.write(data)
                io.close
            end
            
            #
            # deletes the whole storage directory... beware...
            #
            def purge
                FileUtils.remove_dir @basepath
            end 
            
            #
            # check whether the key has a file  in the file storage
            def has_key? (fei)
                File.exist?(compute_file_path(fei))
            end
            
            def remove (fei, workitem)
                
                fei_path = compute_file_path(fei)
                
                if File.exist?(fei_path)
                    File.delete(fei_path)
                else
                    raise "Object not found at #{fei_path}"
                end
            end
            
            def [] (fei)
                fei_path = compute_file_path(fei)
                
                return nil if not File.exist?(fei_path)
                
                data = IO.read(compute_file_path(fei))
                object = YAML.load(data)
                
                object.application_context = @application_context
                
                return object
            end
            
            def length
                return count_expression(0, @basepath)
            end
            
            protected 
            
            def count_expression (count, item)
                
                return count + 1 if OpenWFE::ends_with(item, ".yaml")
                
                if File.stat(item).directory?
                    
                    d = Dir.new(item)
                    d.each do |i|
                        next if i == "." or i == ".."
                        i = item + "/" + i
                        count = count_expression(count, i)
                    end
                    d.close()
                end
                
                return count
            end
            
            def compute_file_path (fei)
                raise "this should be implemented in a subclass"
            end
            
        end        
        
    end