#!/usr/bin/env bash
# Apply AXP CVE allowlist onto msm-4.14 (after Stage1+combo4).
# Source: AXP kernel_patches + cve_checker strict list / bisect slices.
#
# Safety (2026-09-29 review):
# - Default: ABORT on first patch failure (no continue-with-partial-tree).
# - Keep *.rej / *.orig under CVE_REJECT_DIR (do not silently delete).
# - Treat large line-offsets / fuzz as WARN or FAIL (mis-apply risk).
# - Set CVE_STRICT_CONTINUE=1 only for forensic runs (explicit).
set -euo pipefail

KP="${AXP_KERNEL_PATCHES:-/srv/rom/references/axp/kernel_patches}"
KERNEL_DIR="${1:-/srv/rom/src/lineage/kernel/google/msm-4.14}"
HERE="$(cd "$(dirname "$0")" && pwd)"
LIST="${CVE_STRICT_LIST:-$HERE/cve-strict.list}"
DENY="${CVE_DENYLIST:-$HERE/cve-denylist.txt}"
LOG_DIR="${CVE_APPLY_LOG_DIR:-/srv/rom/artifacts/009-axp-los23-port/cve-stage}"
CONTINUE="${CVE_STRICT_CONTINUE:-0}"
# Reject apply if GNU patch reports fuzz >= this (0 = disable fuzz fail)
MAX_FUZZ="${CVE_MAX_FUZZ:-1}"
# Reject if any hunk offset abs(lines) >= this (0 = disable)
MAX_ABS_OFFSET="${CVE_MAX_ABS_OFFSET:-200}"
DRY_RUN=0
[[ "${2:-}" == "--dry-run" ]] && DRY_RUN=1

if [[ ! -d "$KERNEL_DIR/include/linux" ]]; then
  echo "error: kernel dir missing: $KERNEL_DIR" >&2
  exit 1
fi
if [[ ! -d "$KP" ]]; then
  echo "error: AXP kernel_patches missing: $KP" >&2
  exit 1
fi
if [[ ! -f "$LIST" ]]; then
  echo "error: list missing: $LIST" >&2
  exit 1
fi

mkdir -p "$LOG_DIR"
STAMP=$(date -u +%Y%m%dT%H%M%SZ)
LOG="$LOG_DIR/apply-cve-strict-${STAMP}.log"
FAIL_LIST="$LOG_DIR/apply-cve-strict-${STAMP}.fail.txt"
REJECT_DIR="${CVE_REJECT_DIR:-$LOG_DIR/rejects-${STAMP}}"
mkdir -p "$REJECT_DIR"
: >"$FAIL_LIST"

declare -A DENY_MAP=()
if [[ -f "$DENY" ]]; then
  while IFS= read -r d || [[ -n "$d" ]]; do
    [[ -z "$d" || "$d" =~ ^# ]] && continue
    if [[ "$d" == *"/kernel_patches/"* ]]; then
      DENY_MAP["${d##*/kernel_patches/}"]=1
    else
      DENY_MAP["$d"]=1
    fi
  done <"$DENY"
fi

ok=0
fail=0
skip=0
miss=0
quality_fail=0

echo "=== CVE strict apply kernel=$KERNEL_DIR dry_run=$DRY_RUN continue=$CONTINUE max_fuzz=$MAX_FUZZ max_abs_offset=$MAX_ABS_OFFSET ===" | tee "$LOG"

while IFS= read -r rel || [[ -n "$rel" ]]; do
  [[ -z "$rel" || "$rel" =~ ^# ]] && continue
  if [[ -n "${DENY_MAP[$rel]:-}" ]]; then
    echo "SKIP_DENY $rel" | tee -a "$LOG"
    skip=$((skip + 1))
    continue
  fi
  p="$KP/$rel"
  if [[ ! -f "$p" ]]; then
    echo "MISS $rel" | tee -a "$LOG"
    miss=$((miss + 1))
    echo "$rel" >>"$FAIL_LIST"
    if [[ "$CONTINUE" != "1" ]]; then
      echo "error: missing patch (abort)" >&2
      exit 1
    fi
    continue
  fi

  args=(-p1 --batch -d "$KERNEL_DIR" --forward --no-backup-if-mismatch)
  if [[ "$DRY_RUN" -eq 1 ]]; then
    args+=(--dry-run)
  fi

  patch_log=$(mktemp)
  set +e
  patch "${args[@]}" <"$p" >"$patch_log" 2>&1
  prc=$?
  set -e
  cat "$patch_log" >>"$LOG"

  # Quality: fuzz / large offsets even when exit 0
  fuzz_max=0
  abs_off_max=0
  eval "$(python3 -c '
import re, sys
text = open(sys.argv[1], errors="replace").read()
fuzz = off = 0
for m in re.finditer(r"with fuzz (\d+)", text):
    fuzz = max(fuzz, int(m.group(1)))
for m in re.finditer(r"\(offset ([+-]?\d+) lines\)", text):
    off = max(off, abs(int(m.group(1))))
print(f"fuzz_max={fuzz}")
print(f"abs_off_max={off}")
' "$patch_log")"
  rm -f "$patch_log"

  qbad=0
  if [[ "$MAX_FUZZ" -gt 0 && "$fuzz_max" -ge "$MAX_FUZZ" ]]; then
    echo "QUALITY_FAIL fuzz=$fuzz_max>=$MAX_FUZZ $rel" | tee -a "$LOG"
    qbad=1
  fi
  if [[ "$MAX_ABS_OFFSET" -gt 0 && "$abs_off_max" -ge "$MAX_ABS_OFFSET" ]]; then
    echo "QUALITY_FAIL abs_offset=$abs_off_max>=$MAX_ABS_OFFSET $rel" | tee -a "$LOG"
    qbad=1
  fi

  if [[ "$prc" -eq 0 && "$qbad" -eq 0 ]]; then
    echo "OK $rel (fuzz_max=$fuzz_max abs_off_max=$abs_off_max)" | tee -a "$LOG"
    ok=$((ok + 1))
    continue
  fi

  # Failure path: preserve rejects
  echo "FAIL $rel patch_rc=$prc fuzz_max=$fuzz_max abs_off_max=$abs_off_max" | tee -a "$LOG"
  echo "$rel" >>"$FAIL_LIST"
  fail=$((fail + 1))
  [[ "$qbad" -eq 1 ]] && quality_fail=$((quality_fail + 1))

  safe=$(echo "$rel" | tr '/' '_')
  dest="$REJECT_DIR/$safe"
  mkdir -p "$dest"
  # move any rej/orig created under kernel tree
  while IFS= read -r -d '' rej; do
    mv "$rej" "$dest/" 2>/dev/null || cp -a "$rej" "$dest/" || true
  done < <(find "$KERNEL_DIR" -name '*.rej' -print0 2>/dev/null)
  while IFS= read -r -d '' orig; do
    mv "$orig" "$dest/" 2>/dev/null || cp -a "$orig" "$dest/" || true
  done < <(find "$KERNEL_DIR" -name '*.orig' -print0 2>/dev/null)
  cp -a "$p" "$dest/patch" 2>/dev/null || true
  echo "rejects_kept=$dest" | tee -a "$LOG"

  if [[ "$CONTINUE" != "1" ]]; then
    echo "error: abort on FAIL (set CVE_STRICT_CONTINUE=1 to keep going)" >&2
    echo "CVE strict ABORT OK=$ok FAIL=$fail QUALITY_FAIL=$quality_fail SKIP_DENY=$skip MISS=$miss log=$LOG" | tee -a "$LOG"
    exit 1
  fi
done <"$LIST"

echo "CVE strict done OK=$ok FAIL=$fail QUALITY_FAIL=$quality_fail SKIP_DENY=$skip MISS=$miss dry_run=$DRY_RUN continue=$CONTINUE log=$LOG rejects=$REJECT_DIR" | tee -a "$LOG"

if [[ "$fail" -gt 0 && "$CONTINUE" != "1" ]]; then
  exit 1
fi
if [[ "$ok" -eq 0 && "$DRY_RUN" -eq 0 ]]; then
  echo "error: zero CVE patches applied" >&2
  exit 1
fi