#!/usr/bin/env bash
# Flatten rustdoc output so the crate serves at the doc root rather than under
# <crate>/. Moves the crate's pages up to the doc root and drops one ../ from
# each page's references to the shared assets (CSS/JS, search index, source),
# scaled to the page's depth.
# Env: DOCROOT (default target/doc), CRATE (default coursebank).
set -euo pipefail
docroot="${DOCROOT:-target/doc}"
crate="${CRATE:-coursebank}"
[ -d "$docroot/$crate" ] || { echo "no $docroot/$crate; did you build the docs?" >&2; exit 1; }
cp -a "$docroot/$crate/." "$docroot/"
rm -rf "${docroot:?}/${crate:?}"
resources='static\.files/\|crates\.js\|search-index\|search\.desc/\|src/\|settings\.html\|help\.html\|trait\.impl/\|type\.impl/'
while IFS= read -r -d '' f; do
  rel="${f#"$docroot"/}"
  depth=$(printf '%s' "$rel" | tr -cd '/' | wc -c)
  pat=''; for ((i=0; i<=depth; i++)); do pat="\\.\\./$pat"; done
  rep=''; for ((i=0; i<depth;  i++)); do rep="../$rep"; done
  sed -i "s#${pat}\(${resources}\)#${rep}\1#g" "$f"
done < <(find "$docroot" -name '*.html' -print0)
echo "flattened $crate into $docroot"