#
#--
# Copyright (c) 2006-2007, 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
#

require 'openwfe/rudefinitions'
require 'openwfe/util/dollar'
require 'openwfe/expressions/fe_raw'

#
# a few help methods for expressions

module OpenWFE

    #
    # Returns the text stored as the children of the given expression
    # 
    def OpenWFE.fetch_text_content (expression, workitem, escape=false)

        text = ""

        expression.children.each do |child|
            if child.kind_of?(RawExpression)
                text << child.fei.to_s
            else
                text << child.to_s
            end
            #text << "\n"
        end

        text = dosub(text, expression, workitem) \
            if not escape

        return text
    end

    #
    # looks up for 'value', 'variable-value' and then for 'field-value'
    # if necessary.
    #
    def OpenWFE.lookup_value (flow_expression, workitem, prefix='')

        return OpenWFE\
            .lookup_vf_attribute(flow_expression, workitem, 'value', prefix)
    end

    #
    # looks up for 'ref', 'variable-ref' and then for 'field-ref'
    # if necessary.
    #
    def OpenWFE.lookup_ref (flow_expression, workitem, prefix='')

        return OpenWFE\
            .lookup_vf_attribute(flow_expression, workitem, 'ref', prefix)
    end

    #
    # Looks up for value attributes like 'field-ref' or 'variable-value'
    #
    def OpenWFE.lookup_vf_attribute \
        (flow_expression, workitem, att_name, prefix='')

        prefix = "#{prefix.to_s}-" if prefix != ''

        v = flow_expression.lookup_attribute("#{prefix}#{att_name}", workitem)

        return v if v

        v = flow_expression\
            .lookup_attribute("#{prefix}variable-#{att_name}", workitem)

        return flow_expression.lookup_variable(v) if v

        v = flow_expression\
            .lookup_attribute("#{prefix}field-#{att_name}", workitem)

        return workitem.attributes[v] if v

        return nil
    end

    #
    # Looks up for a value, a variable or a field (in that order).
    # 
    #def OpenWFE.lookup_vvf_attribute (flow_expression, workitem, prefix)
    #    raise "missing prefix" unless prefix
    #    v = flow_expression.lookup_attribute("#{prefix}-value", workitem)
    #    return v if v
    #    v = flow_expression.lookup_attribute("#{prefix}-variable", workitem)
    #    return flow_expression.lookup_variable(v) if v
    #    v = flow_expression.lookup_attribute("#{prefix}-field", workitem)
    #    return workitem.attributes[v] if v
    #    return nil
    #end

    #
    # sets the '__result__' field of the workitem
    #
    def OpenWFE.set_result (workitem, result)

        workitem.attributes[FIELD_RESULT] = result
    end

end