{{- /* Convert Hugo's HTML table of contents to JSON using regex substitutions */ -}}
{{- /* Input: page object */ -}}
{{- /* Output: JSON structure representing the table of contents */ -}}
{{- $toc := .TableOfContents -}}
{{- /* Remove the nav wrapper and all newlines/extra whitespace */ -}}
{{- $toc = $toc | replaceRE "<nav[^>]*>" "" -}}
{{- $toc = $toc | replaceRE "</nav>" "" -}}
{{- $toc = $toc | replaceRE "\\n\\s*" "" -}}
{{- /* Step 1: Replace <ul> with opening bracket for children array */ -}}
{{- $toc = $toc | replaceRE "<ul>" "[" -}}
{{- $toc = $toc | replaceRE "</ul>" "]" -}}
{{- /* Step 2: Replace <li><a href="#ID">TITLE</a> with {"id":"ID","title":"TITLE" */ -}}
{{- $toc = $toc | replaceRE "<li><a href=\"#([^\"]+)\">([^<]+)</a>" "{\"id\":\"$1\",\"title\":\"$2\"" -}}
{{- /* Step 3: Replace </li> with } */ -}}
{{- $toc = $toc | replaceRE "</li>" "}" -}}
{{- /* Step 4: Handle nested structure - replace ][ with ],[ (sibling arrays) */ -}}
{{- $toc = $toc | replaceRE "\\]\\[" "],[" -}}
{{- /* Step 4b: Handle nested structure - replace [  with ,"children":[ (child arrays) */ -}}
{{- $toc = $toc | replaceRE "\"\\[" "\",\"children\":[" -}}
{{- /* Step 5: Add commas between sibling objects - replace }{ with },{ */ -}}
{{- $toc = $toc | replaceRE "\\}\\{" "},{" -}}
{{- /* Step 6: Wrap the entire structure */ -}}
{{- $toc = print "{\"sections\":" $toc "}" -}}
{{- /* Step 7: Remove all newlines and extra whitespace for clean output */ -}}
{{- $toc = $toc | replaceRE "\\n\\s*" "" -}}
{{- /* Output the JSON - use safeHTML to prevent quote escaping */ -}}
{{- $toc | safeHTML -}}