#!/usr/bin/env bash
#
# check-lockfiles.sh — every committed Cargo.lock is current.
#
# A lockfile is stale when cargo would change it: a crate's version was bumped,
# or a dependency was added, and the lock was not regenerated. This tree holds
# many workspaces that depend on one another by path, so a version bump in one
# leaves the locks of the others behind. Nothing notices until a job that
# passes `--locked` fails, for a reason that has nothing to do with what the
# job tests.
#
# For each directory that holds a tracked Cargo.lock this runs
#
#     cargo update --workspace --locked
#
# which resolves the workspace against its lock and fails if the lock would
# change. It reads the registry index and any git dependency; it downloads no
# crate and builds nothing.
#
#   check-lockfiles.sh            every tracked Cargo.lock, less the list below
#   check-lockfiles.sh DIR ...    exactly these directories
#
# Exit 0: every lock is current. Exit 1: at least one is stale, or could not be
# checked. A lock that could not be checked (no network, say) fails the run too,
# under its own heading, so nobody goes looking for a stale lock that is not
# one.
set -uo pipefail

# Directories that hold a Cargo.lock cargo does not read. Each needs a reason,
# and each must still exist: a stale entry fails the run.
SKIP=(
  # A vendored crate, patched into jouledesk-rs. Cargo resolves it as part of
  # that workspace, against that workspace's lock; its own lock is the
  # upstream's, kept with the vendored source.
  "jouledesk/jouledesk-rs/vendor/libwebrtc"
)

skipped() { local d; for d in "${SKIP[@]}"; do [ "$d" = "$1" ] && return 0; done; return 1; }

if [ $# -gt 0 ]; then
  dirs=("$@")
else
  cd "$(git rev-parse --show-toplevel)" || exit 1
  for d in "${SKIP[@]}"; do
    if [ ! -f "$d/Cargo.lock" ]; then
      echo "check-lockfiles: the skip list names $d, which holds no Cargo.lock. Remove the entry." >&2
      exit 1
    fi
  done
  dirs=()
  while IFS= read -r l; do
    d=$(dirname "$l")
    skipped "$d" || dirs+=("$d")
  done < <(git ls-files | grep -E '(^|/)Cargo\.lock$')
fi

if [ ${#dirs[@]} -eq 0 ]; then
  echo "check-lockfiles: found no Cargo.lock to check." >&2
  exit 1
fi

stale=(); unchecked=()
for d in "${dirs[@]}"; do
  out=$( (cd "$d" && cargo update --workspace --locked) 2>&1 ); rc=$?
  if [ $rc -eq 0 ]; then
    continue
  elif printf '%s' "$out" | grep -qE -- '--locked was passed|lock file .* (is missing|needs to be updated)'; then
    stale+=("$d")
    echo "STALE  $d"
    printf '%s\n' "$out" | grep -E '^error|^Caused by|^  ' | head -6 | sed 's/^/         /'
  else
    unchecked+=("$d")
    echo "ERROR  $d (cargo could not resolve it; this is not a verdict on the lock)"
    printf '%s\n' "$out" | tail -8 | sed 's/^/         /'
  fi
done

if [ ${#stale[@]} -gt 0 ]; then
  echo
  echo "Stale lockfiles. Regenerate each, and commit the result:"
  for d in "${stale[@]}"; do echo "    (cd $d && cargo update --workspace)"; done
fi
if [ ${#unchecked[@]} -gt 0 ]; then
  echo
  echo "Could not be checked: ${unchecked[*]}"
fi
if [ ${#stale[@]} -gt 0 ] || [ ${#unchecked[@]} -gt 0 ]; then
  exit 1
fi
echo "check-lockfiles: ${#dirs[@]} lockfiles, all current."