#!/usr/bin/env bash
# Usage: scripts/check-stubs.sh <js|scala|fsharp>
# Runs each module M01..M13 (and the optional M07b) that has tests against the stubs in src/. Fails if any module's tests pass,
# and also fails (exit 2) on tooling/build errors, so a broken toolchain can never look like "stubs fail".
set -uo pipefail
track="${1:?usage: check-stubs.sh <js|scala|fsharp>}"
repo="$(cd "$(dirname "$0")/.." && pwd)"
dir="$repo/$track"
export PATH="$HOME/.dotnet:$HOME/.local/bin:$PATH"

case "$track" in
  js)     tool=node;      has() { compgen -G "$dir/test/m$1-*.test.js" >/dev/null; } ;;
  scala)  tool="${SCALA_CLI:-scala-cli}"; has() { compgen -G "$dir/test/M$1*.test.scala" >/dev/null; } ;;
  fsharp) tool=dotnet;    has() { compgen -G "$dir/tests/M$1*.fs" >/dev/null; } ;;
  *) echo "unknown track: $track" >&2; exit 2 ;;
esac
if ! command -v "$tool" >/dev/null 2>&1; then
  echo "check-stubs: required tool '$tool' not found on PATH" >&2; exit 2
fi
[ -x "$dir/test.sh" ] || { echo "check-stubs: $dir/test.sh missing or not executable" >&2; exit 2; }

# Succeeds if the (ANSI-stripped) output in $1 shows tests really ran and at least one failed
# (stub throws / ??? / failwith count as failures), as opposed to a compile or tooling error.
tests_failed() {
  case "$track" in
    js)     ! grep -qE 'SyntaxError|ERR_MODULE_NOT_FOUND|does not provide an export|ReferenceError' <<<"$1" \
              && grep -qE '^ℹ tests [1-9]' <<<"$1" && grep -qE '^ℹ fail [1-9]' <<<"$1" ;;
    scala)  ! grep -qE 'Compilation failed|\[error\]|Error compiling|Downloading failed' <<<"$1" \
              && grep -qE '==> X' <<<"$1" ;;
    fsharp) ! grep -qE 'error (FS|MSB|NU)[0-9]+|[Bb]uild failed|Build FAILED' <<<"$1" \
              && grep -qE '[1-9][0-9]* (failed|errored)' <<<"$1" ;;
  esac
}

# Modules in course order; "07b" is the optional Module 7b.
modules="01 02 03 04 05 06 07 07b 08 09 10 11 12 13"

# Scala's `./test.sh M07` (munit glob "*M07*") and F#'s (Expecto --filter-test-list, a substring) also select the
# M07b tests. Their failures would hide an M07 that wrongly passes, so for such a module run the tests in a temp
# copy without the longer-tagged modules' test files (F#: also without their line in tests/Snake.Tests.fsproj).
run_module() {
  local n="$1" longer="" t f tmp
  if [ "$track" != js ]; then
    for t in $modules; do [[ "$t" == "$n"?* ]] && has "$t" && longer="$longer $t"; done
  fi
  if [ -z "$longer" ]; then (cd "$dir" && ./test.sh "M$n" 2>&1); return; fi
  tmp="$(mktemp -d)"
  tar -C "$repo" --exclude=.git --exclude=node_modules --exclude=bin --exclude=obj \
      --exclude=.scala-build --exclude=.bsp --exclude=.superpowers -cf - . | tar -C "$tmp" -xf -
  for t in $longer; do
    case "$track" in
      scala)  rm -f "$tmp"/scala/test/M"$t"*.test.scala ;;
      fsharp) for f in "$tmp"/fsharp/tests/M"$t"*.fs; do
                rm -f "$f"; sed -i "/Include=\"$(basename "$f")\"/d" "$tmp/fsharp/tests/Snake.Tests.fsproj"
              done ;;
    esac
  done
  (cd "$tmp/$track" && ./test.sh "M$n" 2>&1); local rc=$?
  rm -rf "$tmp"
  return $rc
}

status=0
for n in $modules; do
  m="M$n"
  if ! has "$n"; then echo "$m: no tests"; continue; fi
  out="$(run_module "$n")"; rc=$?
  out="$(sed $'s/\x1b\\[[0-9;?]*[A-Za-z]//g' <<<"$out")"
  if [ $rc -eq 0 ]; then
    echo "$m: FAIL (tests pass against stubs)"; status=1
  elif tests_failed "$out"; then
    echo "$m: ok (fails against stubs)"
  else
    echo "$m: ERROR (tooling/build error, exit $rc; not a test failure)" >&2
    echo "$out" >&2
    exit 2
  fi
done
exit $status