#
# Copyright (c) 2005-2006, 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: codec.rb 2865 2006-06-23 14:54:07Z jmettraux $
#

#
# "hecho en Costa Rica"
#

#require 'base64'
require 'rexml/document'

require 'definitions'
require 'utils'
require 'workitem'


module OpenWFE

    #
    # Takes as input some XML element and returns is decoded (as an instance)
    #
    def OpenWFE.decode (xmlElt)

        return nil if not xmlElt

        #puts "decode() xmlElt.name is >#{xmlElt.name}<"

        return decodeList(xmlElt) if xmlElt.name == STORES
        return decodeStore(xmlElt) if xmlElt.name == STORE
        return decodeList(xmlElt) if xmlElt.name == HEADERS
        return decodeHeader(xmlElt) if xmlElt.name == HEADER

        return decodeLaunchOk(xmlElt) if xmlElt.name == OK

        return decodeList(xmlElt) if xmlElt.name == HISTORY
        return decodeHistoryItem(xmlElt) if xmlElt.name == HISTORY_ITEM

        return decodeList(xmlElt) \
            if xmlElt.name == FLOW_EXPRESSION_IDS
        return decodeFlowExpressionId(xmlElt) \
            if xmlElt.name == FLOW_EXPRESSION_ID

        return decodeInFlowWorkItem(xmlElt) \
            if xmlElt.name == IN_FLOW_WORKITEM

        return decodeList(xmlElt) if xmlElt.name == LAUNCHABLES
        return decodeLaunchable(xmlElt) if xmlElt.name == LAUNCHABLE

        return decodeList(xmlElt) if xmlElt.name == EXPRESSIONS
        return decodeExpression(xmlElt) if xmlElt.name == EXPRESSION

        return decodeAttribute(xmlElt.elements[1]) if xmlElt.name == ATTRIBUTES

        #
        # default

        return decodeAttribute(xmlElt)

        #raise \
        #    ArgumentException, \
        #    "Cannot decode : '"+xmlElt.name+"' "+xmlElt.to_s()
    end

    #
    # Takes some OpenWFE Ruby instance and returns it as XML
    #
    def OpenWFE.encode (owfeData)

        #puts "encode() #{owfeData.inspect}"

        return encodeLaunchItem(owfeData) \
            if owfeData.kind_of?(LaunchItem)

        return encodeFlowExpressionId(owfeData) \
            if owfeData.kind_of?(FlowExpressionId)

        return encodeInFlowWorkItem(owfeData) \
            if owfeData.kind_of?(InFlowWorkItem)

        raise \
            ArgumentException, \
            "Cannot encode : "+owfeData.inspect()
    end

    private


        #
        # DECODE
        #

        def OpenWFE.decodeList (xmlElt)

            l = []

            xmlElt.elements.each do |elt| 
                #puts " ... #{elt.inspect()}"
                l.push(decode(elt))
            end

            return l
        end


        def OpenWFE.decodeLaunchable (xmlElt)

            launchable = Launchable.new()

            launchable.url = xmlElt.attributes[URL]
            launchable.engineId = xmlElt.attributes[ENGINE_ID]

            return launchable
        end


        def OpenWFE.decodeExpression (xmlElt)

            exp = Expression.new()
            
            #exp.id = decode(firstElement(xmlElt, "//"+FLOW_EXPRESSION_ID))
            exp.id = decode(firstElement(xmlElt))

            exp.applyTime = xmlElt.attributes[APPLY_TIME]
            exp.state = xmlElt.attributes[STATE]
            exp.stateSince = xmlElt.attributes[STATE_SINCE]

            return exp
        end


        def OpenWFE.decodeStore (xmlElt)

            store = Store.new()

            store.name = xmlElt.attributes[NAME]
            store.workitemCount = xmlElt.attributes[WORKITEM_COUNT]
            store.workitemCount = Integer(store.workitemCount)
            store.permissions = xmlElt.attributes[PERMISSIONS]

            return store
        end


        def OpenWFE.decodeHeader (xmlElt)

            header = Header.new()

            header.lastModified = xmlElt.attributes[A_LAST_MODIFIED]
            header.locked = parseBoolean(xmlElt.attributes[A_LOCKED])
            header.flowExpressionId = decode(firstElement(xmlElt, FLOW_EXPRESSION_ID))
            header.attributes = decode(firstElement(xmlElt, ATTRIBUTES))

            return header
        end


        def OpenWFE.decodeFlowExpressionId (xmlElt)

            fei = FlowExpressionId.new()

            fei.owfeVersion = xmlElt.attributes[OWFE_VERSION]
            fei.engineId = xmlElt.attributes[ENGINE_ID]
            fei.initialEngineId = xmlElt.attributes[INITIAL_ENGINE_ID]

            fei.workflowDefinitionUrl = xmlElt.attributes[WORKFLOW_DEFINITION_URL]
            fei.workflowDefinitionName = xmlElt.attributes[WORKFLOW_DEFINITION_NAME]
            fei.workflowDefinitionRevision = xmlElt.attributes[WORKFLOW_DEFINITION_REVISION]

            fei.workflowInstanceId = xmlElt.attributes[WORKFLOW_INSTANCE_ID]

            fei.expressionName = xmlElt.attributes[EXPRESSION_NAME]
            fei.expressionId = xmlElt.attributes[EXPRESSION_ID]

            #puts " ... fei.expressionName is >#{fei.expressionName}<"
            #puts " ... fei.wfid is >#{fei.workflowInstanceId}<"

            return fei
        end


        def OpenWFE.decodeAttribute (xmlElt)

            #puts "decodeAttribute() '#{xmlElt.name}' --> '#{xmlElt.text}'"

            #
            # atomic types

            return xmlElt.text if xmlElt.name == E_STRING
            return Integer(xmlElt.text) if xmlElt.name == E_INTEGER
            return Integer(xmlElt.text) if xmlElt.name == E_LONG
            return Float(xmlElt.text) if xmlElt.name == E_DOUBLE
            return parseBoolean(xmlElt.text) if xmlElt.name == E_BOOLEAN

            return xmlElt if xmlElt.name == E_XML

            return Base64Attribute.new(xmlElt.txt) if xmlElt.name == E_BASE64

            #
            # composite types

            return decodeList(xmlElt) if xmlElt.name == E_LIST

            if xmlElt.name == E_SMAP or xmlElt.name == E_MAP

                map = {}
                map[MAP_TYPE] = xmlElt.name

                #xmlElt.elements.each("//"+M_ENTRY) do |e| 
                xmlElt.elements.each(M_ENTRY) do |e| 
                    #puts "decodeAttribute() >#{e}<"
                    decodeEntry(e, map)
                end

                return map
            end

            #puts docToString(xmlElt.document())

            raise \
                ArgumentError, \
                "Cannot decode <#{xmlElt.name}/> in \n"+\
                docToString(xmlElt.document())
        end

        def OpenWFE.decodeEntry (xmlElt, map)

            key = xmlElt.elements[1]
            val = xmlElt.elements[2]

            #
            # this parse method supports the old style and the [new] light
            # style/schema
            #

            key = key.elements[1] if key.name == M_KEY
            val = val.elements[1] if val.name == M_VALUE

            key = decode(key)
            val = decode(val)

            #puts "decodeEntry() k >#{key}< v >#{val}<"
            #puts "decodeEntry() subject '#{val}'" if key == '__subject__' 

            map[key] = val
        end

        def OpenWFE.parseBoolean (string)

            return string.strip.downcase == 'true'
        end

        def OpenWFE.decodeHistoryItem (xmlElt)

            hi = HistoryItem.new

            hi.author = xmlElt.attributes[A_AUTHOR]
            hi.date = xmlElt.attributes[A_DATE]
            hi.host = xmlElt.attributes[A_HOST]
            hi.text = xmlElt.text

            hi.wfdName = xmlElt.attributes[WORKFLOW_DEFINITION_NAME]
            hi.wfdRevision = xmlElt.attributes[WORKFLOW_DEFINITION_REVISION]
            hi.wfInstanceId = xmlElt.attributes[WORKFLOW_INSTANCE_ID]
            hi.expressionId = xmlElt.attributes[EXPRESSION_ID]

            return hi
        end


        def OpenWFE.decodeLaunchOk (xmlElt)

            sFei = xmlElt.attributes[A_FLOW_ID]

            return true if not sFei

            return FlowExpressionId.strToFei(sFei)
        end


        def OpenWFE.decodeInFlowWorkItem (xmlElt)

            wi = InFlowWorkItem.new()

            wi.lastModified = xmlElt.attributes[A_LAST_MODIFIED]
            wi.attributes = decode(firstElement(xmlElt, ATTRIBUTES))

            wi.participantName = xmlElt.attributes[A_PARTICIPANT_NAME]
            wi.flowExpressionId = decode(firstElement(firstElement(xmlElt, E_LAST_EXPRESSION_ID), FLOW_EXPRESSION_ID))

            wi.dispatchTime = xmlElt.attributes[A_DISPATCH_TIME]

            # TODO : decode filter

            wi.history = decode(firstElement(xmlElt, HISTORY))

            return wi
        end


        #
        # ENCODE
        #

        def OpenWFE.docToString (xml, decl=true)

            s = ""

            if decl and xml[0].kind_of? REXML::XMLDecl
                xml << REXML::XMLDecl.new()
            end

            xml.write(s, 0)
            return s
        end


        def OpenWFE.encodeItem (item, elt)

            elt.attributes[A_LAST_MODIFIED] = item.lastModified

            eAttributes = REXML::Element.new(ATTRIBUTES)

            eAttributes << encodeAttribute(item.attributes)

            elt << eAttributes
        end


        def OpenWFE.encodeLaunchItem (launchitem)

            doc = REXML::Document.new()

            root = REXML::Element.new(E_LAUNCHITEM)

            encodeItem(launchitem, root)

            root.attributes[WORKFLOW_DEFINITION_URL] = \
                launchitem.workflowDefinitionUrl

            # TODO :
            #
            # - encode descriptionMap
            #
            # - replyTo is not necessary

            #doc.root = root
            doc << root

            return docToString(doc)
        end


        def OpenWFE.encodeInFlowItem (item, elt)

            encodeItem(item, elt)

            elt.attributes[A_PARTICIPANT_NAME] = item.participantName

            eLastExpressionId = REXML::Element.new(E_LAST_EXPRESSION_ID)

            eLastExpressionId << encodeFlowExpressionId(item.lastExpressionId)

            elt << eLastExpressionId
        end


        def OpenWFE.encodeInFlowWorkItem (item)

            doc = REXML::Document.new()

            root = REXML::Element.new(IN_FLOW_WORKITEM)

            encodeInFlowItem(item, root)

            root.attributes[A_DISPATCH_TIME] = item.dispatchTime

            # add filter ? no

            encodeHistory(item, root)

            doc << root

            s = docToString(doc)
            #puts "encoded :\n#{s}"
            return s
        end


        def OpenWFE.encodeHistory (item, elt)

            eHistory = REXML::Element.new(HISTORY)

            item.history.each do |hi|

                ehi = REXML::Element.new(HISTORY_ITEM)

                ehi.attributes[A_AUTHOR] = hi.author
                ehi.attributes[A_DATE] = hi.date
                ehi.attributes[A_HOST] = hi.host

                ehi.attributes[WORKFLOW_DEFINITION_NAME] = hi.wfdName
                ehi.attributes[WORKFLOW_DEFINITION_REVISION] = hi.wfdRevision
                ehi.attributes[WORKFLOW_INSTANCE_ID] = hi.wfInstanceId
                ehi.attributes[EXPRESSION_ID] = hi.expressionId

                eHistory << ehi
            end

            elt << eHistory
        end


        def OpenWFE.encodeAttribute (att)

            #puts "encodeAttribute() att.class is #{att.class}"

            return encodeAtomicAttribute(E_STRING, att) \
                if att.kind_of? String
            return encodeAtomicAttribute(E_INTEGER, att) \
                if att.kind_of? Fixnum
            return encodeAtomicAttribute(E_DOUBLE, att) \
                if att.kind_of? Float

            return encodeXmlAttribute(att) \
                if att.kind_of? REXML::Element

            return encodeAtomicAttribute(E_BOOLEAN, true) \
                if att.kind_of? TrueClass
            return encodeAtomicAttribute(E_BOOLEAN, false) \
                if att.kind_of? FalseClass

            return encodeBase64Attribute(att) \
                if att.kind_of? Base64Attribute

            #
            # missing : BASE64...

            return encodeMapAttribute(att) if att.kind_of? Hash
            return encodeListAttribute(att) if att.kind_of? Array

            #
            # default

            return encodeAtomicAttribute(E_STRING, att)

            #raise \
            #    ArgumentException, \
            #    "Cannot encode attribute of class '#{att.class}'"
        end


        def OpenWFE.encodeXmlAttribute (elt)

            return elt if elt.name == E_XML

            #
            # else, wrap within <raw-xml>...</raw-xml>

            e = REXML::Element.new(E_XML)
            e << elt

            return e
        end


        def OpenWFE.encodeBase64Attribute (att)

            e = REXML::Element.new(E_BASE64)
            e.text = att.content

            return e
        end


        def OpenWFE.encodeAtomicAttribute (name, value)

            elt = REXML::Element.new(name)
            #elt << REXML::Text.new(value.to_s())
            elt.add_text(value.to_s())

            return elt
        end


        def OpenWFE.encodeListAttribute (list)

            elt = REXML::Element.new(E_LIST)

            list.each do |e|
                elt << encodeAttribute(e)
            end

            return elt
        end


        def OpenWFE.encodeMapAttribute (hash)

            name = hash[MAP_TYPE]
            name = 'map' if name == nil

            elt = REXML::Element.new(name)

            hash.each_key do |key|

                next if key == MAP_TYPE

                eEntry = REXML::Element.new(M_ENTRY)

                val = hash[key]

                eEntry << encodeAttribute(key)
                eEntry << encodeAttribute(val)

                elt << eEntry
            end

            return elt
        end


        def OpenWFE.encodeFlowExpressionId (fei)

            elt = REXML::Element.new(FLOW_EXPRESSION_ID)

            elt.attributes[OWFE_VERSION] = fei.owfeVersion
            elt.attributes[ENGINE_ID] = fei.engineId
            elt.attributes[INITIAL_ENGINE_ID] = fei.initialEngineId

            elt.attributes[WORKFLOW_DEFINITION_URL] = fei.workflowDefinitionUrl
            elt.attributes[WORKFLOW_DEFINITION_NAME] = fei.workflowDefinitionName
            elt.attributes[WORKFLOW_DEFINITION_REVISION] = fei.workflowDefinitionRevision
            elt.attributes[WORKFLOW_INSTANCE_ID] = fei.workflowInstanceId

            elt.attributes[EXPRESSION_NAME] = fei.expressionName
            elt.attributes[EXPRESSION_ID] = fei.expressionId

            return elt
        end

end