#!/usr/bin/env bash
# Row 72 (#1566): rerun the six mutants the row 68 reviewers named against a
# tree with the candidate tests. Usage: mutants.sh <tree>. Each mutant edits
# one line of bus-service.sh or adapter.sh, runs the pin tests, and restores
# the file from git. Prints "killed" or "SURVIVED" per mutant; exit 1 if any
# mutant survives, a sed doesn't change its file, or the unmutated run fails.
set -euo pipefail
TREE="$(cd "${1:?usage: mutants.sh <tree>}" && pwd)"
cd "$TREE"
BS=scripts/bus-service.sh
AD=adapters/claude/adapter.sh
PATTERN='directory pin|symlink default|pin with a space|pins the claude|MOSAIC_CLAUDE_BIN wins'
TESTS=(packages/cli/tests/host.test.mjs packages/harness/tests/claude-session.test.mjs)
run_tests() { node --test --test-name-pattern="$PATTERN" "${TESTS[@]}" >"$1" 2>&1; }

# name | file | sed expression
MUTANTS=(
  'bs-no-f|'"$BS"'|s/\[ -f "\$bin" \] \&\& \[ -x "\$bin" \]/[ -e "$bin" ] \&\& [ -x "$bin" ]/'
  'bs-x-only|'"$BS"'|s/\[ -f "\$bin" \] \&\& \[ -x "\$bin" \]/[ -x "$bin" ]/'
  'ad-no-f|'"$AD"'|s/\[ -f "\$MOSAIC_CLAUDE_BIN" \] \&\& \[ -x "\$MOSAIC_CLAUDE_BIN" \]/[ -e "$MOSAIC_CLAUDE_BIN" ] \&\& [ -x "$MOSAIC_CLAUDE_BIN" ]/'
  'ad-x-only|'"$AD"'|s/\[ -f "\$MOSAIC_CLAUDE_BIN" \] \&\& \[ -x "\$MOSAIC_CLAUDE_BIN" \]/[ -x "$MOSAIC_CLAUDE_BIN" ]/'
  'bs-resolve-default|'"$BS"'|s/^        bin="\$(command -v claude || true)"$/        bin="$(command -v claude || true)"; [ -z "$bin" ] || bin="$(readlink -f "$bin")"/'
  'ad-unquoted-run|'"$AD"'|s/^"\$CLAUDE" -p /$CLAUDE -p /'
)

OUT="${OUT:-$TREE/.mutants}"
mkdir -p "$OUT"
git diff --quiet -- "$BS" "$AD" || { echo "refusing: $BS or $AD already modified" >&2; exit 1; }
run_tests "$OUT/baseline.log" || { echo "baseline run failed: $OUT/baseline.log" >&2; exit 1; }
echo "baseline: pass"
status=0
for m in "${MUTANTS[@]}"; do
  IFS='|' read -r name file expr <<<"$m"
  sed -i -e "$expr" "$file"
  if git diff --quiet -- "$file"; then
    echo "$name: NOT APPLIED (sed matched nothing)"; status=1; continue
  fi
  git diff -- "$file" >"$OUT/$name.diff"
  if run_tests "$OUT/$name.log"; then
    echo "$name: SURVIVED"; status=1
  else
    echo "$name: killed ($(grep -E '^✖' "$OUT/$name.log" | sed 's/ ([0-9.]*ms)$//' | sort -u | tr '\n' ';' ))"
  fi
  git checkout -q -- "$file"
done
git diff --quiet -- "$BS" "$AD" || { echo "restore failed" >&2; exit 1; }
exit "$status"