#
#--
# Copyright (c) 2007, 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"
#
# John Mettraux at openwfe.org
#


module OpenWFE

    #
    # A ConditionMixin is a mixin for flow expressions like 'if' and 'break' for
    # example.
    # It allows for shorter notations like
    #
    #     <if test="${f:approved} == true"/>
    #
    # or
    #
    #     _loop do
    #         participant :graphical_designer
    #         participant :business_analyst
    #         _break :if => "${f:approved}"
    #     end
    #
    module ConditionMixin

        def eval_condition (attname, workitem)

            conditional = lookup_attribute(attname, workitem)
            rconditional = lookup_attribute("r"+attname.to_s, workitem)

            if rconditional and not conditional
                return instance_eval(rconditional)
            end

            return nil unless conditional

            #ldebug { "eval_condition() 0 for  '#{conditional}'" }

            conditional = from_xml(conditional)

            #ldebug { "eval_condition() 1 for  '#{conditional}'" }

            conditional = do_quote(conditional)

            ldebug { "eval_condition() 2 for  '#{conditional}'" }

            result = instance_eval(conditional)

            ldebug { "eval_condition() 3 result is  '#{result}'" }

            return (result == "true" or result == true)
        end

        private

            def from_xml (string)

                s = string
                s.gsub!("&gt;", ">")
                s.gsub!("&lt;", "<")
                s
            end

            def do_quote (string)

                i = string.index("==")
                i = string.index("!=") unless i
                i = string.index("<") unless i
                i = string.index(">") unless i

                return '"' + string + '"' unless i

                '"' +
                string[0..i-1].strip +
                '" ' +
                string[i..i+2] +
                ' "' +
                string[i+2..-1].strip +
                '"'
            end
    end

end