#!/usr/bin/env bash
# ChromeOS 5.15 vs Ubuntu HWE 6.17：板级 machine 与 helpers 的 unified diff（iDisp / HDMI 相关）
set -euo pipefail
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
REPO_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
CH="${CH:-$REPO_ROOT/chromiumos_kernel/v5.15}"
UB="${UB:-$REPO_ROOT/kernel-src/linux-hwe-6.17-6.17.0}"
OUT="${OUT:-$REPO_ROOT/patches/ubuntu-hwe-6.17/reference}"

FILES=(
  sound/soc/intel/boards/sof_rt5682.c
  sound/soc/intel/boards/sof_board_helpers.c
)

mkdir -p "$OUT"
for f in "${FILES[@]}"; do
  if [[ ! -f "$CH/$f" || ! -f "$UB/$f" ]]; then
    echo "WARN: skip (missing): $f" >&2
    continue
  fi
  safe="${f//\//_}"
  dest="$OUT/diff-u_${safe}.txt"
  ( diff -u "$CH/$f" "$UB/$f" || true ) > "$dest"
  echo "Wrote $dest ($(wc -l < "$dest") lines)"
done
echo "Done. See STREAM_PCM_PARAMS_CHROME_UBUNTU_NOTES.md §6 与 REANALYSIS §7.2。"