#!/bin/bash
# Apply a package list to the OpenWrt .config.
#
# The list is a plain text file of package names, whitespace separated, any
# number per line. Section headers switch how the following packages are
# applied, and a leading '-' on a name removes that package:
#
#   ##built-in          the packages after this are set to =y  (default)
#   ##module            ... are set to =m
#   ##remove            ... are set to =n
#   -luci-app-ttyd      set to =n regardless of the current section
#   pkg  # comment      text after a single # is ignored
#
# Existing CONFIG_PACKAGE_ lines are rewritten in place rather than appended,
# so running this repeatedly does not grow .config.
#
# Usage: ./add-openwrt-packages.sh [options] <package_list.txt | ->
#
#   -y, --yes            do not ask for confirmation
#   -n, --dry-run        show the resulting diff, change nothing
#       --no-defconfig   do not run make defconfig afterwards
#       --no-backup      do not keep a .config.bak
#       --strict         exit non-zero if any listed package was not found
#   -h, --help           show this help
#
# Run it from the OpenWrt root:  ./helper/add-openwrt-packages.sh <list>
#
# Author: Zhe Yuan

set -euo pipefail
umask 022

PKG_FILE=""
ASSUME_YES=false
DRY_RUN=false
RUN_DEFCONFIG=true
KEEP_BACKUP=true
STRICT=false

info() { echo "[INFO] $*"; }
warn() { echo "[WARN] $*"; }
err()  { echo "[ERROR] $*" >&2; }

usage() { sed -n '2,29p' "$0" | sed 's/^# \{0,1\}//;s/^#$//'; }

confirm() {
  local question="$1" default="$2" reply=""
  [ "$ASSUME_YES" = true ] && return 0
  if [ "$default" = "yes" ]; then
    read -r -p "$question [Y/n]: " reply || reply=""
    case "${reply:-}" in [nN] | [nN][oO]) return 1 ;; *) return 0 ;; esac
  else
    read -r -p "$question [y/N]: " reply || reply=""
    case "${reply:-}" in [yY] | [yY][eE][sS]) return 0 ;; *) return 1 ;; esac
  fi
}

while [ $# -gt 0 ]; do
  case "$1" in
    -y|--yes) ASSUME_YES=true ;;
    -n|--dry-run) DRY_RUN=true ;;
    --no-defconfig) RUN_DEFCONFIG=false ;;
    --no-backup) KEEP_BACKUP=false ;;
    --strict) STRICT=true ;;
    -h|--help) usage; exit 0 ;;
    -) PKG_FILE="-" ;;
    -*) err "Unknown option: $1"; echo "Run '$0 --help' for usage." >&2; exit 1 ;;
    *)
      if [ -n "$PKG_FILE" ]; then
        err "Only one package list can be given."
        exit 1
      fi
      PKG_FILE="$1"
      ;;
  esac
  shift
done

[ -t 0 ] || ASSUME_YES=true

if [ -z "$PKG_FILE" ]; then
  err "No package list given."
  usage >&2
  exit 1
fi

if [ "$PKG_FILE" != "-" ] && [ ! -f "$PKG_FILE" ]; then
  err "Package list not found: $PKG_FILE"
  exit 1
fi

if [ ! -d package ] || [ ! -f Makefile ] || [ ! -f feeds.conf.default ]; then
  err "Must run inside the OpenWrt root directory."
  err "From the OpenWrt root, run it as: ./helper/$(basename "$0")"
  exit 1
fi

if [ ! -f .config ]; then
  info "No .config yet; running make defconfig first..."
  make defconfig >/dev/null
fi

PACKAGE_INDEX="tmp/.config-package.in"
PACKAGE_INFO="tmp/.packageinfo"
if [ ! -f "$PACKAGE_INDEX" ] || [ ! -f "$PACKAGE_INFO" ]; then
  info "Generating package metadata..."
  make defconfig >/dev/null
fi

# --- Parse the list ------------------------------------------------------
# Section headers are handled BEFORE stripping comments: the old
# `sub(/#[^#].*/,"")` left a bare '#' behind, which was then reported as a
# missing package named '#'.
parse_list() {
  awk '
    BEGIN { mode = "y" }
    {
      line = $0
      if (line ~ /^[ \t]*##/) {
        if (line ~ /^[ \t]*##built-in/) { mode = "y"; next }
        if (line ~ /^[ \t]*##module/)   { mode = "m"; next }
        if (line ~ /^[ \t]*##remove/)   { mode = "n"; next }
        print "[WARN] unknown section header, ignored: " line > "/dev/stderr"
        next
      }
      sub(/#.*$/, "", line)
      n = split(line, t, /[ \t]+/)
      for (i = 1; i <= n; i++) {
        tok = t[i]; m = mode
        if (tok == "") continue
        if (substr(tok, 1, 1) == "-") { tok = substr(tok, 2); m = "n" }
        if (tok == "") continue
        print tok "\t" m
      }
    }
  '
}

if [ "$PKG_FILE" = "-" ]; then
  ENTRIES="$(parse_list)"
  PKG_LABEL="(stdin)"
else
  ENTRIES="$(parse_list < "$PKG_FILE")"
  PKG_LABEL="$PKG_FILE"
fi

if [ -z "$ENTRIES" ]; then
  err "No packages found in $PKG_LABEL."
  exit 1
fi

# --- Read the current state once -----------------------------------------
declare -A CUR=()
declare -A DEF=()
while IFS= read -r line; do
  case "$line" in
    CONFIG_PACKAGE_*=*) CUR["${line%%=*}"]="${line#*=}" ;;
    "# CONFIG_PACKAGE_"*" is not set")
      s="${line#\# }"
      CUR["${s% is not set}"]="n"
      ;;
    CONFIG_DEFAULT_*=y) DEF["${line%%=*}"]="y" ;;
  esac
done < .config

# --- Verify and classify --------------------------------------------------
package_exists() {
  local pkg="$1"
  if [ -f "$PACKAGE_INDEX" ] &&
    awk -v key="PACKAGE_$pkg" '$1 == "config" && $2 == key { found = 1; exit }
      END { exit !found }' "$PACKAGE_INDEX"; then
    return 0
  fi
  if [ -f "$PACKAGE_INFO" ] && grep -Fqx "Package: $pkg" "$PACKAGE_INFO"; then
    return 0
  fi
  return 1
}

DESIRED="$(mktemp "${TMPDIR:-/tmp}/desired.XXXXXX")"
NEWCFG="$(mktemp ./.config.new.XXXXXX)"
trap 'rm -f "$DESIRED" "$NEWCFG"' EXIT

declare -a MISSING=() SKIPPED=() PLANNED=() INVALID=()

while IFS=$'\t' read -r pkg mode; do
  [ -z "$pkg" ] && continue

  if ! [[ "$pkg" =~ ^[A-Za-z0-9._+-]+$ ]]; then
    INVALID+=("$pkg")
    continue
  fi

  sym="CONFIG_PACKAGE_$pkg"
  cur="${CUR[$sym]:-}"

  # Already provided by the target defaults: nothing to write, no churn.
  if [ "$mode" = "y" ] && [ -n "${DEF[CONFIG_DEFAULT_$pkg]:-}" ] && [ "$cur" != "m" ]; then
    SKIPPED+=("$pkg (target default)")
    continue
  fi

  if [ "$cur" = "$mode" ]; then
    SKIPPED+=("$pkg (already =$mode)")
    continue
  fi

  # A removal of something that was never enabled needs no check.
  if [ "$mode" != "n" ] && ! package_exists "$pkg"; then
    MISSING+=("$pkg")
    continue
  fi

  printf '%s\t%s\n' "$sym" "$mode" >> "$DESIRED"
  PLANNED+=("$pkg: ${cur:-unset} -> $mode")
done <<< "$ENTRIES"

if [ ${#INVALID[@]} -gt 0 ]; then
  warn "Ignored ${#INVALID[@]} entries with invalid package names:"
  printf '   %s\n' "${INVALID[@]}"
fi

if [ ! -s "$DESIRED" ]; then
  info "Nothing to change; .config already matches $PKG_LABEL."
  if [ ${#MISSING[@]} -gt 0 ]; then
    warn "Packages not found (check feeds or spelling):"
    printf '   %s\n' "${MISSING[@]}"
    warn "Try: ./scripts/feeds update -a && ./scripts/feeds install -a"
    [ "$STRICT" = true ] && exit 1
  fi
  exit 0
fi

# --- Merge into .config ---------------------------------------------------
# Existing symbols are rewritten where they already are, so the file neither
# grows nor reorders; duplicates left behind by older versions collapse.
awk -F'\t' '
  FNR == NR { want[$1] = $2; order[++nk] = $1; next }
  {
    key = ""
    if ($0 ~ /^CONFIG_PACKAGE_[^=]+=/) { key = $0; sub(/=.*$/, "", key) }
    else if ($0 ~ /^# CONFIG_PACKAGE_[^ ]+ is not set$/) {
      # Extract by string, not by field: FS is a tab here, so $2 is empty
      # on .config lines and the symbol would never be matched.
      key = $0; sub(/^# /, "", key); sub(/ is not set$/, "", key)
    }
    if (key != "" && (key in want)) {
      if (!(key in done)) {
        done[key] = 1
        if (want[key] == "n") print "# " key " is not set"
        else print key "=" want[key]
      }
      next
    }
    print
  }
  END {
    for (i = 1; i <= nk; i++) {
      k = order[i]
      if (k in done) continue
      if (want[k] == "n") print "# " k " is not set"
      else print k "=" want[k]
    }
  }
' "$DESIRED" .config > "$NEWCFG"

echo
echo "========================================"
echo " Planned .config changes"
echo "========================================"
printf '   %s\n' "${PLANNED[@]}"
echo "   ---"
echo "   change: ${#PLANNED[@]}   unchanged: ${#SKIPPED[@]}   not found: ${#MISSING[@]}"
echo "========================================"

if [ ${#MISSING[@]} -gt 0 ]; then
  warn "Packages not found (check feeds or spelling):"
  printf '   %s\n' "${MISSING[@]}"
  warn "Try: ./scripts/feeds update -a && ./scripts/feeds install -a"
fi

if [ "$DRY_RUN" = true ]; then
  echo
  diff -u .config "$NEWCFG" || true
  echo
  info "Dry run complete; .config was not modified."
  [ "$STRICT" = true ] && [ ${#MISSING[@]} -gt 0 ] && exit 1
  exit 0
fi

echo
if ! confirm "Apply these changes to .config?" yes; then
  info "Aborted by user."
  exit 0
fi

[ "$KEEP_BACKUP" = true ] && cp -a .config .config.bak
mv -f "$NEWCFG" .config
chmod 644 .config
trap 'rm -f "$DESIRED"' EXIT

if [ "$RUN_DEFCONFIG" = true ]; then
  info "Running make defconfig..."
  make defconfig >/dev/null

  # defconfig silently reverts a removal whose package something else selects,
  # and can demote =y to =m. Without this check that stays invisible.
  declare -a REVERTED=()
  declare -A FINAL=()
  while IFS= read -r line; do
    case "$line" in
      CONFIG_PACKAGE_*=*) FINAL["${line%%=*}"]="${line#*=}" ;;
      "# CONFIG_PACKAGE_"*" is not set")
        s="${line#\# }"
        FINAL["${s% is not set}"]="n"
        ;;
    esac
  done < .config

  while IFS=$'\t' read -r sym mode; do
    got="${FINAL[$sym]:-unset}"
    [ "$got" = "$mode" ] || REVERTED+=("${sym#CONFIG_PACKAGE_}: wanted =$mode, got =$got")
  done < "$DESIRED"

  if [ ${#REVERTED[@]} -gt 0 ]; then
    warn "make defconfig changed ${#REVERTED[@]} of the requested states:"
    printf '   %s\n' "${REVERTED[@]}"
    warn "Usually a dependency pulled the package back in."
  fi
fi

echo
echo "========================================"
echo "OK  Applied ${#PLANNED[@]} change(s) from $PKG_LABEL"
[ "$KEEP_BACKUP" = true ] && echo "   Backup: .config.bak"
echo "========================================"

if [ "$STRICT" = true ] && [ ${#MISSING[@]} -gt 0 ]; then
  exit 1
fi