From af881c07fa1d210d79878eb5c4bff9f92626ff1d Mon Sep 17 00:00:00 2001
From: Michael Smith <xmldoc@users.sourceforge.net>
Date: Thu, 27 Apr 2006 08:59:37 +0000
Subject: [PATCH] Added two new params: html.head.legalnotice.link.types and
 html.head.legalnotice.link.multiple.

If the value of the generate.legalnotice.link is non-zero, then
the stylesheet generates (in the head section of the HTML source)
either a single HTML link element or, if the value of the
html.head.legalnotice.link.multiple is non-zero, one link element
for each link type specified. Each link has the following
attributes:

  - a rel attribute whose value is derived from the value of
    html.head.legalnotice.link.types

  - an href attribute whose value is set to the URL of the file
    containing the legalnotice

  - a title attribute whose value is set to the title of the
    corresponding legalnotice (or a title programatically
    determined by the stylesheet)

For example:

  <link rel="copyright" href="ln-id2524073.html" title="Legal Notice">

Closes #1476450. Thanks to Sam Steingold.
---
 xsl/html/chunk-common.xsl                     | 65 +++++++++++++++++
 xsl/html/param.ent                            |  2 +
 xsl/html/param.xweb                           |  4 ++
 xsl/params/generate.legalnotice.link.xml      | 29 ++++++--
 .../html.head.legalnotice.link.multiple.xml   | 37 ++++++++++
 .../html.head.legalnotice.link.types.xml      | 72 +++++++++++++++++++
 6 files changed, 205 insertions(+), 4 deletions(-)
 create mode 100644 xsl/params/html.head.legalnotice.link.multiple.xml
 create mode 100644 xsl/params/html.head.legalnotice.link.types.xml

diff --git a/xsl/html/chunk-common.xsl b/xsl/html/chunk-common.xsl
index d6d07be06..31228db6e 100644
--- a/xsl/html/chunk-common.xsl
+++ b/xsl/html/chunk-common.xsl
@@ -700,6 +700,16 @@
       </xsl:for-each>
     </xsl:if>
 
+    <!-- * if we have a legalnotice and user wants it output as a -->
+    <!-- * separate page and $html.head.legalnotice.link.types is -->
+    <!-- * non-empty, we generate a link or links for each value in -->
+    <!-- * $html.head.legalnotice.link.types -->
+    <xsl:if test="//legalnotice
+                  and not($generate.legalnotice.link = 0)
+                  and not($html.head.legalnotice.link.types = '')">
+      <xsl:call-template name="make.legalnotice.head.links"/>
+    </xsl:if>
+
     <xsl:call-template name="user.head.content"/>
   </head>
 </xsl:template>
@@ -969,6 +979,61 @@
     </xsl:choose>
 </xsl:template>
 
+<!-- ==================================================================== -->
+<!-- * The following does tail-recursion through a space-separated -->
+<!-- * list of link types specified in $html.head.legalnotice.link.types, -->
+<!-- * popping off link types and generating links for them until it -->
+<!-- * depletes the list. -->
+  
+<xsl:template name="make.legalnotice.head.links">
+  <!-- * the following ID is used as part of the legalnotice filename; -->
+  <!-- * we need it in order to construct the filename for use in the -->
+  <!-- * value of the href attribute on the link -->
+  <xsl:param name="id">
+    <xsl:call-template name="object.id">
+      <xsl:with-param name="object" select="//legalnotice[1]"/>
+    </xsl:call-template>
+  </xsl:param>
+  <xsl:param name="linktype">
+    <xsl:choose>
+      <xsl:when test="contains($html.head.legalnotice.link.types, ' ')">
+        <xsl:value-of
+            select="normalize-space(
+                    substring-before($html.head.legalnotice.link.types, ' '))"/>
+      </xsl:when>
+      <xsl:otherwise>
+        <xsl:value-of select="$html.head.legalnotice.link.types"/>
+      </xsl:otherwise>
+    </xsl:choose>
+  </xsl:param>
+  <xsl:param
+      name="remaining.linktypes"
+      select="concat(
+              normalize-space(
+              substring-after($html.head.legalnotice.link.types, ' ')),' ')"/>
+  <xsl:if test="not($linktype = '')">
+    <link rel="{$linktype}">
+      <xsl:attribute name="href">
+        <xsl:value-of select="concat('ln-',$id,$html.ext)"/>
+      </xsl:attribute>
+      <xsl:attribute name="title">
+        <xsl:apply-templates select="//legalnotice[1]"
+                             mode="object.title.markup.textonly"/>
+      </xsl:attribute>
+    </link>
+    <xsl:call-template name="make.legalnotice.head.links">
+      <!-- * pop the next value off the list of link types -->
+      <xsl:with-param
+          name="linktype"
+          select="substring-before($remaining.linktypes, ' ')"/>
+      <!-- * remove the link type from the list of remaining link types -->
+      <xsl:with-param
+          name="remaining.linktypes"
+          select="substring-after($remaining.linktypes, ' ')"/>
+    </xsl:call-template>
+  </xsl:if>
+</xsl:template>
+
 <!-- ==================================================================== -->
 
 <xsl:template match="processing-instruction('dbhtml')">
diff --git a/xsl/html/param.ent b/xsl/html/param.ent
index 73112d4cf..d9211a293 100644
--- a/xsl/html/param.ent
+++ b/xsl/html/param.ent
@@ -70,6 +70,8 @@
 <!ENTITY html.cleanup SYSTEM "../params/html.cleanup.xml">
 <!ENTITY html.ext SYSTEM "../params/html.ext.xml">
 <!ENTITY html.extra.head.links SYSTEM "../params/html.extra.head.links.xml">
+<!ENTITY html.head.legalnotice.link.types SYSTEM "../params/html.head.legalnotice.link.types.xml">
+<!ENTITY html.head.legalnotice.link.multiple SYSTEM "../params/html.head.legalnotice.link.multiple.xml">
 <!ENTITY html.longdesc SYSTEM "../params/html.longdesc.xml">
 <!ENTITY html.longdesc.link SYSTEM "../params/html.longdesc.link.xml">
 <!ENTITY html.stylesheet SYSTEM "../params/html.stylesheet.xml">
diff --git a/xsl/html/param.xweb b/xsl/html/param.xweb
index 42abeb77a..020a22794 100644
--- a/xsl/html/param.xweb
+++ b/xsl/html/param.xweb
@@ -170,6 +170,8 @@ stylesheet like this:</para>
 &author.othername.in.middle;
 &generate.legalnotice.link;
 &generate.revhistory.link;
+&html.head.legalnotice.link.types;
+&html.head.legalnotice.link.multiple;
 </reference>
 
 <reference id="refentry"><title>Reference Pages</title>
@@ -535,6 +537,8 @@ around all these parameters.</para>
 <src:fragref linkend="html.cleanup.frag"/>
 <src:fragref linkend="html.ext.frag"/>
 <src:fragref linkend="html.extra.head.links.frag"/>
+<src:fragref linkend="html.head.legalnotice.link.types.frag"/>
+<src:fragref linkend="html.head.legalnotice.link.multiple.frag"/>
 <src:fragref linkend="html.longdesc.frag"/>
 <src:fragref linkend="html.longdesc.link.frag"/>
 <src:fragref linkend="html.stylesheet.frag"/>
diff --git a/xsl/params/generate.legalnotice.link.xml b/xsl/params/generate.legalnotice.link.xml
index b2f12a394..e843ec709 100644
--- a/xsl/params/generate.legalnotice.link.xml
+++ b/xsl/params/generate.legalnotice.link.xml
@@ -14,10 +14,31 @@
 
 <refsect1><title>Description</title>
 
-<para>If non-zero, the contents of <tag>legalnotice</tag> are written
-to a separate HTML file and a link to the file is
-generated. Otherwise, <tag>legalnotice</tag> contents are rendered on
-the title page.</para>
+<para>If the value of <parameter>generate.legalnotice.link</parameter>
+is non-zero, the stylesheet:
+
+<itemizedlist>
+  <listitem>
+    <para>writes the contents of <tag>legalnotice</tag> to a separate
+    HTML file</para>
+  </listitem>
+  <listitem>
+    <para>inserts a hyperlink to the <tag>legalnotice</tag> file</para>
+  </listitem>
+  <listitem>
+    <para>adds (in the HTML <literal>head</literal>) either a single
+    <literal>link</literal> or element or multiple
+    <literal>link</literal> elements (depending on the value of the
+    <parameter>html.head.legalnotice.link.multiple</parameter>
+    parameter), with the value or values derived from the
+    <parameter>html.head.legalnotice.link.types</parameter>
+    parameter</para>
+  </listitem>
+  </itemizedlist>
+
+  Otherwise, if <parameter>generate.legalnotice.link</parameter> is
+  zero, <tag>legalnotice</tag> contents are rendered on the title
+  page.</para>
 
 </refsect1>
 </refentry>
diff --git a/xsl/params/html.head.legalnotice.link.multiple.xml b/xsl/params/html.head.legalnotice.link.multiple.xml
new file mode 100644
index 000000000..5f02ff9c1
--- /dev/null
+++ b/xsl/params/html.head.legalnotice.link.multiple.xml
@@ -0,0 +1,37 @@
+<refentry id="html.head.legalnotice.link.multiple">
+<refmeta>
+<refentrytitle>html.head.legalnotice.link.multiple</refentrytitle>
+<refmiscinfo role="type">boolean</refmiscinfo>
+</refmeta>
+<refnamediv>
+<refname>html.head.legalnotice.link.multiple</refname>
+<refpurpose>Generate multiple link instances in html head for legalnotice?</refpurpose>
+</refnamediv>
+
+<refsynopsisdiv>
+<src:fragment id='html.head.legalnotice.link.multiple.frag'><xsl:param name="html.head.legalnotice.link.multiple" select="1"/></src:fragment>
+</refsynopsisdiv>
+
+<refsect1><title>Description</title>
+
+<para>If <parameter>html.head.legalnotice.link.multiple</parameter> is
+non-zero and the value of
+<parameter>html.head.legalnotice.link.types</parameter> contains
+multiple link types, then the stylesheet generates (in the
+<literal>head</literal> section of the HTML source) one
+<literal>link</literal> element for each link type specified. For
+example, if the value of
+<parameter>html.head.legalnotice.link.types</parameter> is
+“<literal>copyright license</literal>”:
+
+<screen>  &lt;link rel="copyright" href="ln-id2524073.html" title="Legal Notice">
+  &lt;link rel="license" href="ln-id2524073.html" title="Legal Notice"></screen>
+
+ Otherwise, the stylesheet generates generates a single
+ <literal>link</literal> instance; for example:
+
+<screen>  &lt;link rel="copyright license" href="ln-id2524073.html" title="Legal Notice"></screen>
+ 
+</para>
+</refsect1>
+</refentry>
diff --git a/xsl/params/html.head.legalnotice.link.types.xml b/xsl/params/html.head.legalnotice.link.types.xml
new file mode 100644
index 000000000..69313b7d3
--- /dev/null
+++ b/xsl/params/html.head.legalnotice.link.types.xml
@@ -0,0 +1,72 @@
+<refentry id="html.head.legalnotice.link.types">
+<refmeta>
+<refentrytitle>html.head.legalnotice.link.types</refentrytitle>
+<refmiscinfo role="type">string</refmiscinfo>
+</refmeta>
+<refnamediv>
+<refname>html.head.legalnotice.link.types</refname>
+<refpurpose>Specifies link types for legalnotice link in html head</refpurpose>
+</refnamediv>
+
+<refsynopsisdiv>
+<src:fragment id='html.head.legalnotice.link.types.frag'>
+<xsl:param name="html.head.legalnotice.link.types">copyright</xsl:param>
+</src:fragment>
+</refsynopsisdiv>
+
+<refsect1><title>Description</title>
+
+<para>The value of
+<parameter>html.head.legalnotice.link.types</parameter> is a
+space-separated list of link types, as described in <ulink
+url="http://www.w3.org/TR/html401/types.html#type-links" >Section 6.12
+of the HTML 4.01 specification</ulink>. If the value of the
+<parameter>generate.legalnotice.link</parameter> parameter is
+non-zero, then the stylesheet generates (in the
+<literal>head</literal> section of the HTML source) either a single
+HTML <literal>link</literal> element or, if the value of the
+<parameter>html.head.legalnotice.link.multiple</parameter> is
+non-zero, one <literal>link</literal> element for each link type
+specified. Each <literal>link</literal> has the following attributes:
+
+<itemizedlist>
+  <listitem>
+    <para>a <sgmltag class="attribute">rel</sgmltag> attribute whose
+    value is derived from the value of
+    <parameter>html.head.legalnotice.link.types</parameter></para>
+  </listitem>
+  <listitem>
+    <para>an <sgmltag class="attribute">href</sgmltag> attribute whose
+    value is set to the URL of the file containing the
+    <sgmltag>legalnotice</sgmltag></para>
+  </listitem>
+  <listitem>
+    <para>a <sgmltag class="attribute">title</sgmltag> attribute whose
+    value is set to the title of the corresponding
+    <sgmltag>legalnotice</sgmltag> (or a title programatically
+    determined by the stylesheet)</para>
+  </listitem>
+</itemizedlist>
+
+For example:
+
+<screen>  &lt;link rel="license" href="ln-id2524073.html" title="Legal Notice"></screen>
+</para>
+
+<refsect2>
+  <title>About the default value</title>
+  <para>In an ideal world, the default value of
+  <parameter>html.head.legalnotice.link.types</parameter> would
+  probably be “<literal>license</literal>”, since the content of the
+  DocBook <sgmltag>legalnotice</sgmltag> is typically license
+  information, not copyright information. However, the default value
+  is “<literal>copyright</literal>” for pragmatic reasons: because
+  that’s among the set of “recognized link types” listed in <ulink
+  url="http://www.w3.org/TR/html401/types.html#type-links" >Section
+  6.12 of the HTML 4.01 specification</ulink>, and because certain
+  browsers and browser extensions are preconfigured to recognize that
+  value.</para>
+</refsect2>
+
+</refsect1>
+</refentry>
-- 
2.40.0