From f5fa224cd4fd513d88cc7f83eed44e56a0e0859e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martynas=20Jusevi=C4=8Dius?= <martynas@atomgraph.com>
Date: Mon, 27 Jul 2026 12:02:35 +0300
Subject: [PATCH] Add LDH integration seams:
 init-state/init-editor/init-region/toolbar-host

- Extract local:init-state and local:init-editor from main; hosts can call
  init-state from their own entry point and init-editor lazily on first region
- Extract local:init-region from init-editing's per-root body; seeds <p><br/>
  in empty regions so they can hold a caret; callable per-region for hosts
  that render editable regions after the initial page load
- Add local:toolbar-host() seam function (default: ixsl:page()//nav); hosts
  without a nav element override this to point at their own chrome
- Rename breadcrumb ids to rdfa-editor-breadcrumb-* to avoid collisions with
  host page ids; update CSS and navigate.xsl references accordingly

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 docs/ldh/MIGRATION.md       |  4 ++-
 rdfa-editor.css             |  4 +--
 src/edit.xsl                | 56 ++++++++++++++++++++++++++-----------
 src/index.xsl               | 26 ++++++++++++-----
 src/navigate.xsl            | 16 +++++------
 tests/browser/features.mjs  | 10 +++----
 tests/browser/hardening.mjs |  2 +-
 7 files changed, 77 insertions(+), 41 deletions(-)

diff --git a/docs/ldh/MIGRATION.md b/docs/ldh/MIGRATION.md
index 3f22502..a5da131 100644
--- a/docs/ldh/MIGRATION.md
+++ b/docs/ldh/MIGRATION.md
@@ -67,7 +67,9 @@ kept the textarea in sync continuously; the replacement syncs once, declarativel
 Key points: serialize the container's **children only** (no wrapper element —
 parse-rdf-post adds the div); `mode="canonical"` guarantees the stored literal is
 sanitized and free of editing ephemera (chrome, contenteditable, classes, on*
-handlers, unsafe URLs).
+handlers, unsafe URLs). SaxonJS 3 applies `ixsl:set-property` immediately
+(verified in-browser), so the value is readable by `ldh:parse-rdf-post` within
+the same submit event.
 
 ### 4. Asset loading — `layout.xsl`
 
diff --git a/rdfa-editor.css b/rdfa-editor.css
index ed87253..60aa7c4 100644
--- a/rdfa-editor.css
+++ b/rdfa-editor.css
@@ -536,7 +536,7 @@
             }
 
 /* Breadcrumb bar (Fonto-style element path + RDFa subject) */
-            #breadcrumb {
+            #rdfa-editor-breadcrumb {
                 position: fixed;
                 left: 0;
                 right: 0;
@@ -565,7 +565,7 @@
                 margin: 0 4px;
             }
 
-#breadcrumb-subject {
+#rdfa-editor-breadcrumb-subject {
                 font-family: 'Courier New', monospace;
                 font-size: 12px;
                 color: #1565c0;
diff --git a/src/edit.xsl b/src/edit.xsl
index e830f2b..9ad2987 100644
--- a/src/edit.xsl
+++ b/src/edit.xsl
@@ -35,6 +35,12 @@ version="3.0">
         <xsl:sequence select="ixsl:page()//*[contains-token(@class, 'rdfa-editor-content')]"/>
     </xsl:function>
 
+    <!-- where local:init-editing appends the toolbar; hosts without a nav element
+         override this to point at their own chrome -->
+    <xsl:function name="local:toolbar-host" as="element()*">
+        <xsl:sequence select="ixsl:page()//nav"/>
+    </xsl:function>
+
     <xsl:function name="local:root-of" as="element()?">
         <xsl:param name="node"/>
         <xsl:sequence select="$node/ancestor-or-self::*[contains-token(@class, 'rdfa-editor-content')][1]"/>
@@ -346,7 +352,7 @@ version="3.0">
     <!-- ................................ init ................................ -->
 
     <xsl:template name="local:init-editing">
-        <xsl:for-each select="ixsl:page()//nav">
+        <xsl:for-each select="local:toolbar-host()">
             <xsl:result-document href="?." method="ixsl:append-content">
                 <xsl:call-template name="local:render-toolbar"/>
             </xsl:result-document>
@@ -362,23 +368,39 @@ version="3.0">
             </xsl:result-document>
         </xsl:for-each>
         <xsl:for-each select="local:roots()">
-            <!-- boundary-normalize invalid host markup (bare text in blockquote,
-                 blocks inside p, stray inline at region level, ...) before
-                 editability init; the probe keeps the valid case zero-churn -->
-            <xsl:variable name="region" as="element()" select="."/>
-            <xsl:variable name="invalid" as="xs:boolean" select="
-                exists($region//*[not(ancestor-or-self::*[@data-role])][not(cm:valid-nesting(.))])
-                or exists($region//*[not(ancestor-or-self::*[@data-role])]
-                    [cm:structural(local-name(.))][text()[normalize-space()]])
-                or exists($region/(text()[normalize-space()] | *[cm:inline(local-name(.))]))"/>
-            <xsl:if test="$invalid">
-                <xsl:variable name="fixed" as="node()*"
-                    select="cm:wrap-inline-runs(cm:normalize($region/node()), 'p')"/>
-                <ixsl:set-property name="innerHTML"
-                    select="serialize($fixed, map{ 'method': 'html' })" object="$region"/>
-            </xsl:if>
+            <xsl:call-template name="local:init-region">
+                <xsl:with-param name="region" select="."/>
+            </xsl:call-template>
         </xsl:for-each>
-        <xsl:for-each select="local:roots()/*">
+    </xsl:template>
+
+    <!-- per-region bring-up, callable for regions rendered after the initial page
+         (hosts that open editable regions lazily init each one through this) -->
+    <xsl:template name="local:init-region">
+        <xsl:param name="region" as="element()"/>
+
+        <!-- boundary-normalize invalid host markup (bare text in blockquote,
+             blocks inside p, stray inline at region level, ...) before
+             editability init; the probe keeps the valid case zero-churn -->
+        <xsl:variable name="invalid" as="xs:boolean" select="
+            exists($region//*[not(ancestor-or-self::*[@data-role])][not(cm:valid-nesting(.))])
+            or exists($region//*[not(ancestor-or-self::*[@data-role])]
+                [cm:structural(local-name(.))][text()[normalize-space()]])
+            or exists($region/(text()[normalize-space()] | *[cm:inline(local-name(.))]))"/>
+        <xsl:if test="$invalid">
+            <xsl:variable name="fixed" as="node()*"
+                select="cm:wrap-inline-runs(cm:normalize($region/node()), 'p')"/>
+            <ixsl:set-property name="innerHTML"
+                select="serialize($fixed, map{ 'method': 'html' })" object="$region"/>
+        </xsl:if>
+        <!-- an empty region cannot hold a caret: seed a paragraph (the
+             empty-blockquote idiom in local:init-block) -->
+        <xsl:if test="empty($region/*[not(@data-role)])">
+            <xsl:variable name="p" as="element()" select="local:element('p')"/>
+            <xsl:sequence select="ixsl:call($p, 'appendChild', [ local:element('br') ])[current-date() lt xs:date('2000-01-01')]"/>
+            <xsl:sequence select="ixsl:call($region, 'appendChild', [ $p ])[current-date() lt xs:date('2000-01-01')]"/>
+        </xsl:if>
+        <xsl:for-each select="$region/*">
             <xsl:call-template name="local:init-block">
                 <xsl:with-param name="block" select="."/>
             </xsl:call-template>
diff --git a/src/index.xsl b/src/index.xsl
index cbfdfd2..29fd278 100644
--- a/src/index.xsl
+++ b/src/index.xsl
@@ -52,19 +52,31 @@ version="3.0">
          documents into the SaxonJS document pool (SaxonJS.getResource +
          documentPool), keyed by page-relative URI -->
     <xsl:template name="main">
-        <!-- all editor state lives on a single window.rdfaEditor container (mirrors
-             LinkedDataHub's window.LinkedDataHub); reached everywhere via local:editor-state() -->
-        <ixsl:set-property name="rdfaEditor" select="ixsl:call(ixsl:window(), 'Object', [])" object="ixsl:window()"/>
+        <xsl:call-template name="local:init-state"/>
+        <xsl:call-template name="local:init-editor"/>
+    </xsl:template>
+
+    <!-- all editor state lives on a single window.rdfaEditor container (mirrors
+         LinkedDataHub's window.LinkedDataHub); reached everywhere via local:editor-state().
+         Hosts with their own initial template call this from there instead of main -->
+    <xsl:template name="local:init-state">
+        <xsl:variable name="state" select="ixsl:call(ixsl:window(), 'Object', [])"/>
+        <ixsl:set-property name="rdfaEditor" select="$state" object="ixsl:window()"/>
         <xsl:for-each select="('editingSpan', 'range', 'activeBlock', 'draggedBlock',
                 'editRange', 'editingLink', 'insertHost', 'lastUndoHost',
                 'breadcrumbLeaf', 'draggedSectionHeading', 'findNode', 'tocRoot',
                 'slashHost', 'sweepAnchorNode', 'sweepAnchorHost', 'sweepRegion')">
-            <ixsl:set-property name="{.}" select="()" object="local:editor-state()"/>
+            <ixsl:set-property name="{.}" select="()" object="$state"/>
         </xsl:for-each>
-        <ixsl:set-property name="lastUndoTime" select="0" object="local:editor-state()"/>
-        <ixsl:set-property name="findOffset" select="1" object="local:editor-state()"/>
-        <ixsl:set-property name="sweepAnchorOffset" select="0" object="local:editor-state()"/>
+        <ixsl:set-property name="lastUndoTime" select="0" object="$state"/>
+        <ixsl:set-property name="findOffset" select="1" object="$state"/>
+        <ixsl:set-property name="sweepAnchorOffset" select="0" object="$state"/>
+    </xsl:template>
 
+    <!-- the full editor bring-up: page chrome (undo stash, overlay, output modal,
+         toolbar, dialogs, drawers) plus block init of every editable region. Hosts
+         that render regions lazily call this once, when the first region appears -->
+    <xsl:template name="local:init-editor">
         <xsl:call-template name="local:init-undo"/>
         <xsl:call-template name="local:init-overlay"/>
         <xsl:call-template name="local:init-annotate"/>
diff --git a/src/navigate.xsl b/src/navigate.xsl
index 7778afc..a655c8b 100644
--- a/src/navigate.xsl
+++ b/src/navigate.xsl
@@ -35,10 +35,10 @@ version="3.0">
                     <div id="inspector-subject"/>
                     <div id="inspector-body"/>
                 </aside>
-                <footer id="breadcrumb" class="rdfa-editor-ui" role="navigation" aria-label="Document position">
-                    <div id="breadcrumb-path"/>
-                    <div id="breadcrumb-meta">
-                        <span id="breadcrumb-subject"/>
+                <footer id="rdfa-editor-breadcrumb" class="rdfa-editor-ui" role="navigation" aria-label="Document position">
+                    <div id="rdfa-editor-breadcrumb-path"/>
+                    <div id="rdfa-editor-breadcrumb-meta">
+                        <span id="rdfa-editor-breadcrumb-subject"/>
                         <button type="button" id="lint-badge" class="lint-badge"
                             aria-label="RDFa validation issues" style="display: none;"/>
                     </div>
@@ -275,7 +275,7 @@ version="3.0">
                 <ixsl:set-property name="breadcrumbLeaf" select="$leaf" object="local:editor-state()"/>
                 <xsl:variable name="ancestors" as="element()*"
                     select="$leaf/ancestor-or-self::* intersect local:root-of($leaf)/descendant-or-self::*"/>
-                <xsl:for-each select="id('breadcrumb-path', ixsl:page())">
+                <xsl:for-each select="id('rdfa-editor-breadcrumb-path', ixsl:page())">
                     <xsl:result-document href="?." method="ixsl:replace-content">
                         <xsl:for-each select="$ancestors">
                             <xsl:if test="position() gt 1">
@@ -287,17 +287,17 @@ version="3.0">
                         </xsl:for-each>
                     </xsl:result-document>
                 </xsl:for-each>
-                <xsl:for-each select="id('breadcrumb-subject', ixsl:page())">
+                <xsl:for-each select="id('rdfa-editor-breadcrumb-subject', ixsl:page())">
                     <ixsl:set-property name="textContent"
                         select="rdfa:in-scope-subject($leaf, local:document-uri())" object="."/>
                 </xsl:for-each>
             </xsl:when>
             <xsl:otherwise>
                 <ixsl:set-property name="breadcrumbLeaf" select="()" object="local:editor-state()"/>
-                <xsl:for-each select="id('breadcrumb-path', ixsl:page())">
+                <xsl:for-each select="id('rdfa-editor-breadcrumb-path', ixsl:page())">
                     <ixsl:set-property name="textContent" select="''" object="."/>
                 </xsl:for-each>
-                <xsl:for-each select="id('breadcrumb-subject', ixsl:page())">
+                <xsl:for-each select="id('rdfa-editor-breadcrumb-subject', ixsl:page())">
                     <ixsl:set-property name="textContent" select="local:document-uri()" object="."/>
                 </xsl:for-each>
             </xsl:otherwise>
diff --git a/tests/browser/features.mjs b/tests/browser/features.mjs
index ec3c0f6..fe177db 100644
--- a/tests/browser/features.mjs
+++ b/tests/browser/features.mjs
@@ -12,7 +12,7 @@ page.on('pageerror', err => errors.push(String(err)));
 page.on('dialog', d => d.accept());
 
 await page.goto(BASE + '/tests/fixture.html');
-await page.waitForSelector('#breadcrumb', { state: 'attached', timeout: 15000 })
+await page.waitForSelector('#rdfa-editor-breadcrumb', { state: 'attached', timeout: 15000 })
     .catch(() => errors.push('breadcrumb never rendered'));
 await page.waitForSelector('#content > * > [data-role=chrome]', { state: 'attached', timeout: 5000 })
     .catch(() => errors.push('chrome never injected'));
@@ -215,8 +215,8 @@ await page.evaluate(() => {
 await page.keyboard.press('ArrowRight'); // trigger keyup -> breadcrumb refresh
 await page.waitForTimeout(150);
 results.breadcrumb = await page.evaluate(() => ({
-    path: document.getElementById('breadcrumb-path').textContent,
-    subject: document.getElementById('breadcrumb-subject').textContent,
+    path: document.getElementById('rdfa-editor-breadcrumb-path').textContent,
+    subject: document.getElementById('rdfa-editor-breadcrumb-subject').textContent,
 }));
 results.breadcrumb.pathOk = /content›p›strong/.test(results.breadcrumb.path.replace(/\s/g, ''));
 results.breadcrumb.subjectOk = results.breadcrumb.subject === BASE + '/tests/fixture.html';
@@ -229,10 +229,10 @@ await page.evaluate(() => {
 await page.keyboard.press('ArrowRight');
 await page.waitForTimeout(150);
 results.breadcrumb.annotatedLabel = await page.evaluate(() =>
-    document.getElementById('breadcrumb-path').textContent.includes('span[name]'));
+    document.getElementById('rdfa-editor-breadcrumb-path').textContent.includes('span[name]'));
 // crumb click selects the element
 await page.evaluate(() => {
-    const crumbs = [...document.querySelectorAll('#breadcrumb-path .crumb')];
+    const crumbs = [...document.querySelectorAll('#rdfa-editor-breadcrumb-path .crumb')];
     crumbs[crumbs.length - 1].dispatchEvent(new MouseEvent('click', { bubbles: true }));
 });
 results.breadcrumb.clickSelects = await page.evaluate(() =>
diff --git a/tests/browser/hardening.mjs b/tests/browser/hardening.mjs
index 962b16c..6ed14ba 100644
--- a/tests/browser/hardening.mjs
+++ b/tests/browser/hardening.mjs
@@ -135,7 +135,7 @@ results.aria = await page.evaluate(() => ({
     dialogsModal: ['link-dialog', 'figure-dialog', 'find-dialog'].every(id =>
         document.getElementById(id).getAttribute('aria-modal') === 'true'),
     tocNav: document.getElementById('toc-drawer').getAttribute('role') === 'navigation',
-    breadcrumbNav: document.getElementById('breadcrumb').getAttribute('role') === 'navigation',
+    breadcrumbNav: document.getElementById('rdfa-editor-breadcrumb').getAttribute('role') === 'navigation',
     badgeIsButton: document.getElementById('lint-badge').tagName === 'BUTTON',
 }));