This is a followup question to parse XML without using global variables
I want to parse this kind of XML using XSLT 1.0 only:
<root>
<!-- example 1 - no SplitBlock tag -->
<Block id="1" inputPorts="0" outputPorts="1" />
<OutputPort id="2" parent="1" />
<Block id="3" inputPorts="1" outputPorts="0" />
<InputPort id="4" parent="3" />
<Link id="5" source="2" target="4" />
<!-- example 2 - one SplitBlock tag -->
<Block id="6" inputPorts="0" outputPorts="1" />
<OutputPort id="7" parent="6" />
<Block id="8" inputPorts="1" outputPorts="0" />
<InputPort id="9" parent="8" />
<Block id="10" inputPorts="1" outputPorts="0" />
<InputPort id="11" parent="10" />
<SplitBlock id="old-12" inputPorts="1" outputPorts="2" />
<InputPort id="old-13" parent="old-12" />
<OutputPort id="old-14" parent="old-12" />
<OutputPort id="old-15" parent="old-12" />
<Link id="old-16" source="7" target="old-13" />
<Link id="old-17" source="old-14" target="9" />
<Link id="old-18" source="old-15" target="11" />
<!-- example 3 - two connected SplitBlock tags -->
<Block id="19" inputPorts="0" outputPorts="1" />
<OutputPort id="20" parent="19" />
<Block id="21" inputPorts="1" outputPorts="0" />
<InputPort id="22" parent="21" />
<Block id="23" inputPorts="0" outputPorts="1" />
<OutputPort id="24" parent="23" />
<Block id="25" inputPorts="1" outputPorts="0" />
<InputPort id="26" parent="25" />
<SplitBlock id="old-27" inputPorts="1" outputPorts="2" />
<InputPort id="old-28" parent="old-27" />
<OutputPort id="old-29" parent="old-27" />
<OutputPort id="old-30" parent="old-27" />
<SplitBlock id="old-31" inputPorts="2" outputPorts="1" />
<InputPort id="old-32" parent="old-31" />
<InputPort id="old-33" parent="old-31" />
<OutputPort id="old-34" parent="old-31" />
<Link id="old-35" source="20" target="old-28" />
<Link id="old-36" source="old-29" target="22" />
<Link id="old-37" source="old-30" target="old-32" />
<Link id="old-38" source="24" target="old-33" />
<Link id="old-39" source="old-34" target="26" />
</root>
There are multple Block and SplitBlock tags. InputPort and OutputPort tags follow in any order after the Block or SplitBlock tag, as per number available in attributes of Block and SplitBlock tags. In addition, a SplitBlock has either exactly two InputPort tags and one OutputPort tag or one InputPort tag and two OutputPort tags. Also, there are Link tags which connect an OutputPort (which is the source attribute for the Link) to an InputPort (which is the target attribute of the Link) of either Block or SplitBlock. More importantly, a Link is not connected to another Link.
Each Block, SplitBlock, InputPort, OutputPort, and Link tag has a unique id. All tags which should be removed by this transformation are marked with old- in the id attribute.
The expected output is like this:
<root>
<!-- example 1 - no SplitBlock tag -->
<Block id="1" inputPorts="0" outputPorts="1" />
<OutputPort id="2" parent="1" coordinate="0.5" />
<Block id="3" inputPorts="1" outputPorts="0" />
<InputPort id="4" parent="3" coordinate="0.5" />
<Link id="5" source="2" target="4" />
<!-- example 2 - one SplitBlock tag -->
<Block id="6" inputPorts="0" outputPorts="1" />
<OutputPort id="7" parent="6" coordinate="0.5" />
<Block id="8" inputPorts="1" outputPorts="0" />
<InputPort id="9" parent="8" coordinate="0.5" />
<Block id="10" inputPorts="1" outputPorts="0" />
<InputPort id="11" parent="10" coordinate="0.5" />
<Link id="new-40" source="7" target="9" />
<Link id="new-41" source="new-40" target="11" />
<!-- example 3 - two connected SplitBlock tags -->
<Block id="19" inputPorts="0" outputPorts="1" />
<OutputPort id="20" parent="19" coordinate="0.5" />
<Block id="21" inputPorts="1" outputPorts="0" />
<InputPort id="22" parent="21" coordinate="0.5" />
<Block id="23" inputPorts="0" outputPorts="1" />
<OutputPort id="24" parent="23" coordinate="0.5" />
<Block id="25" inputPorts="1" outputPorts="0" />
<InputPort id="26" parent="25" coordinate="0.5" />
<Link id="new-42" source="20" target="22" />
<Link id="new-43" source="new-42" target="26" />
<Link id="new-44" source="24" target="new-43" />
</root>
The aim of this transformation is to replace all SplitBlock tags, its attached InputPort and OutputPort tags, and its attached Link tags with Link tags only. Note that now, Link tags may be connected to other Link tags also along with InputPort and OutputPort tags.
All tags which should be added by this transformation are marked with new- in the id attribute. I tried using generate-id(), but that did not work as expected. I now know that both calls to generate-id() are in the context of the same SplitBlock tag and that can be fixed by passing a different node, but I am not clear how to get a different node.
Visually, the transformation can be explained by these diagrams. The number in the diagrams is their id in the above examples (I have dropped the old- and new- prefixes):
Example 2
Example 3
The Block tags are represented by the big rectangles and the SplitBlock tags are represented by the medium rectangles. The small squares represent the OutputPort tags when on the right of the Block or the SplitBlock and the InputPort tags when on the left. The Link tag is represented by the line between an OutputPort (which is a source for the Link) and an InputPort (which is a target for the Link). In the output, one of the two can be replaced by another Link.
Updated code:
I modified the xsl file from the previous answer by @michael.hor257k. I have found an answer which works correctly for one SplitBlock tag, but not for two connected SplitBlock tags. Here is my effort:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes" />
<xsl:key name="k-in" match="InputPort" use="@parent" />
<xsl:key name="k-out" match="OutputPort" use="@parent" />
<xsl:key name="k-link-target" match="Link" use="@target" />
<xsl:key name="k-link-source" match="Link" use="@source" />
<xsl:key name="k-input" match="InputPort" use="@id" />
<xsl:key name="k-output" match="OutputPort" use="@id" />
<xsl:key name="k-block" match="Block | SplitBlock" use="@id" />
<xsl:template match="/root">
<xsl:copy>
<xsl:for-each select="Block">
<xsl:variable name="inputPorts" select="@inputPorts" />
<xsl:variable name="outputPorts" select="@outputPorts" />
<xsl:copy-of select="." />
<!-- input ports -->
<xsl:for-each select="key('k-in', @id)">
<xsl:copy>
<xsl:copy-of select="@*" />
<xsl:variable name="numerator" select="2 * (position() - 1) + 1" />
<xsl:attribute name="coordinate">
<xsl:value-of select="$numerator div (2 * $inputPorts)" />
</xsl:attribute>
</xsl:copy>
</xsl:for-each>
<!-- output ports -->
<xsl:for-each select="key('k-out', @id)">
<xsl:copy>
<xsl:copy-of select="@*" />
<xsl:variable name="numerator" select="2 * (position() - 1) + 1" />
<xsl:attribute name="coordinate">
<xsl:value-of select="$numerator div (2 * $outputPorts)" />
</xsl:attribute>
</xsl:copy>
</xsl:for-each>
</xsl:for-each>
<xsl:for-each select="SplitBlock">
<xsl:variable name="inputPorts" select="@inputPorts" />
<xsl:variable name="outputPorts" select="@outputPorts" />
<xsl:variable name="inputPortList" select="key('k-in', @id)" />
<xsl:variable name="outputPortList" select="key('k-out', @id)" />
<xsl:variable name="inputPort" select="$inputPortList[position() = 1]" />
<xsl:variable name="outputPort" select="$outputPortList[position() = 1]" />
<xsl:variable name="targetLink" select="key('k-link-target', $inputPort/@id)" />
<xsl:variable name="sourceLink" select="key('k-link-source', $outputPort/@id)" />
<xsl:variable name="newid1" select="generate-id()" />
<xsl:variable name="newid2" select="generate-id($inputPort)" />
<Link>
<xsl:attribute name="id">
<xsl:value-of select="$newid1" />
</xsl:attribute>
<xsl:attribute name="source">
<xsl:value-of select="$targetLink/@source" />
</xsl:attribute>
<xsl:attribute name="target">
<xsl:value-of select="$sourceLink/@target" />
</xsl:attribute>
</Link>
<xsl:choose>
<xsl:when test="$inputPorts = 2 and $outputPorts = 1">
<xsl:variable name="inputPort2" select="$inputPortList[position() = 2]" />
<xsl:variable name="target2Link" select="key('k-link-target', $inputPort2/@id)" />
<Link>
<xsl:attribute name="id">
<xsl:value-of select="$newid2" />
</xsl:attribute>
<xsl:attribute name="source">
<xsl:value-of select="$target2Link/@source" />
</xsl:attribute>
<xsl:attribute name="target">
<xsl:value-of select="$newid1" />
</xsl:attribute>
</Link>
</xsl:when>
<xsl:when test="$inputPorts = 1 and $outputPorts = 2">
<xsl:variable name="outputPort2" select="$outputPortList[position() = 2]" />
<xsl:variable name="source2Link" select="key('k-link-source', $outputPort2/@id)" />
<Link>
<xsl:attribute name="id">
<xsl:value-of select="$newid2" />
</xsl:attribute>
<xsl:attribute name="source">
<xsl:value-of select="$newid1" />
</xsl:attribute>
<xsl:attribute name="target">
<xsl:value-of select="$source2Link/@target" />
</xsl:attribute>
</Link>
</xsl:when>
<xsl:otherwise>
<Error>
<xsl:attribute name="inputPorts">
<xsl:value-of select="$inputPorts" />
</xsl:attribute>
<xsl:attribute name="outputPorts">
<xsl:value-of select="$outputPorts" />
</xsl:attribute>
</Error>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each>
<xsl:for-each select="Link">
<xsl:variable name="sourcePort" select="key('k-output', @source)" />
<xsl:variable name="targetPort" select="key('k-input', @target)" />
<xsl:variable name="sourceBlock" select="key('k-block', $sourcePort/@parent)" />
<xsl:variable name="targetBlock" select="key('k-block', $targetPort/@parent)" />
<xsl:if test="name($sourceBlock) != 'SplitBlock' and name($targetBlock) != 'SplitBlock'">
<xsl:copy-of select="." />
</xsl:if>
</xsl:for-each>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
For Example 2, it gives the correct output as:
<Link id="idm13" source="7" target="9"/>
<Link id="idm14" source="idm13" target="11"/>
However, for Example 3, it gives 4 Link tags instead of 3:
<Link id="idm28" source="20" target="22"/>
<Link id="idm29" source="idm28" target="old-32"/>
<Link id="idm32" source="old-30" target="26"/>
<Link id="idm33" source="24" target="idm32"/>
The correct output should have only 3 Link tags:
<Link id="idm28" source="20" target="22"/>
<Link id="idm32" source="idm28" target="26"/>
<Link id="idm33" source="24" target="idm32"/>
Please help on this now.
My old code below:
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes" />
<xsl:key name="k-in" match="InputPort" use="@parent" />
<xsl:key name="k-out" match="OutputPort" use="@parent" />
<xsl:template match="/root">
<xsl:copy>
<xsl:for-each select="Block">
<xsl:variable name="inputPorts" select="@inputPorts" />
<xsl:variable name="outputPorts" select="@outputPorts" />
<xsl:copy-of select="." />
<!-- input ports -->
<xsl:for-each select="key('k-in', @id)">
<xsl:copy>
<xsl:copy-of select="@*" />
<xsl:variable name="numerator" select="2 * (position() - 1) + 1" />
<xsl:attribute name="coordinate">
<xsl:value-of select="$numerator div (2 * $inputPorts)" />
</xsl:attribute>
</xsl:copy>
</xsl:for-each>
<!-- output ports -->
<xsl:for-each select="key('k-out', @id)">
<xsl:copy>
<xsl:copy-of select="@*" />
<xsl:variable name="numerator" select="2 * (position() - 1) + 1" />
<xsl:attribute name="coordinate">
<xsl:value-of select="$numerator div (2 * $outputPorts)" />
</xsl:attribute>
</xsl:copy>
</xsl:for-each>
</xsl:for-each>
<xsl:for-each select="SplitBlock">
<xsl:variable name="inputPorts" select="@inputPorts" />
<xsl:variable name="outputPorts" select="@outputPorts" />
<xsl:variable name="newid1" select="generate-id()" />
<xsl:variable name="source1id" select="..." /> <!-- TODO: get first source id connected to output port of SplitBlock -->
<xsl:variable name="target1id" select="..." /> <!-- TODO: get first target id connected to input port of SplitBlock -->
<Link>
<xsl:attribute name="id">
<xsl:value-of select="$newid1" />
</xsl:attribute>
<xsl:attribute name="source">
<xsl:value-of select="$source1id" />
</xsl:attribute>
<xsl:attribute name="target">
<xsl:value-of select="$target1id" />
</xsl:attribute>
</Link>
<xsl:choose>
<xsl:when test="$inputPorts = 2 and $outputPorts = 1">
<xsl:variable name="target2id" select="..." /> <!-- TODO: get second target id connected to input port of SplitBlock -->
<Link>
<xsl:attribute name="id">
<xsl:value-of select="generate-id()" /> <!-- FIXME: this generates same id as $newid1 -->
</xsl:attribute>
<xsl:attribute name="source">
<xsl:value-of select="$newid1" />
</xsl:attribute>
<xsl:attribute name="target">
<xsl:value-of select="$target2id" />
</xsl:attribute>
</Link>
</xsl:when>
<xsl:when test="$inputPorts = 1 and $outputPorts = 2">
<xsl:variable name="source2id" select="..." /> <!-- TODO: get second source id connected to output port of SplitBlock -->
<Link>
<xsl:attribute name="id">
<xsl:value-of select="generate-id()" /> <!-- FIXME: this generates same id as $newid1 -->
</xsl:attribute>
<xsl:attribute name="source">
<xsl:value-of select="$source2id" />
</xsl:attribute>
<xsl:attribute name="target">
<xsl:value-of select="$newid1" />
</xsl:attribute>
</Link>
</xsl:when>
<xsl:otherwise>
<Error>
<xsl:attribute name="inputPorts">
<xsl:value-of select="$inputPorts" />
</xsl:attribute>
<xsl:attribute name="outputPorts">
<xsl:value-of select="$outputPorts" />
</xsl:attribute>
</Error>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each>
<xsl:for-each select="Link"> <!-- FIXME: don't copy links connected to SplitBlock -->
<xsl:copy-of select="." />
</xsl:for-each>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
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