#!/usr/bin/env sh
set -eu

METHOD="auto"   # auto|pkg|pip
PIP_USER="--user"

usage() {
  cat <<'EOF'
Usage: install-ansible.sh [--method auto|pkg|pip] [--pip-user|--pip-system]
EOF
}

while [ $# -gt 0 ]; do
  case "$1" in
    --method) METHOD="${2:-}"; shift 2 ;;
    --pip-user) PIP_USER="--user"; shift 1 ;;
    --pip-system) PIP_USER=""; shift 1 ;;
    -h|--help) usage; exit 0 ;;
    *) echo "Unknown arg: $1" >&2; usage; exit 1 ;;
  esac
done

have() { command -v "$1" >/dev/null 2>&1; }

as_root() {
  if [ "$(id -u)" -eq 0 ]; then
    sh -c "$*"
  elif have sudo; then
    sudo sh -c "$*"
  else
    echo "ERROR: need root or sudo: $*" >&2
    exit 1
  fi
}

install_pkg() {
  # macOS
  if [ "$(uname -s)" = "Darwin" ]; then
    if have brew; then
      brew install ansible
      return 0
    fi
    echo "ERROR: Homebrew not found. Install brew first, or use --method pip." >&2
    return 1
  fi

  # Linux package managers (prefer official repos)
  if have apt-get; then
    as_root "apt-get update -y && apt-get install -y ansible"
    return 0
  fi

  if have dnf; then
    as_root "dnf install -y ansible"
    return 0
  fi

  if have yum; then
    as_root "yum install -y ansible"
    return 0
  fi

  if have zypper; then
    as_root "zypper -n install ansible"
    return 0
  fi

  if have pacman; then
    as_root "pacman -Sy --noconfirm ansible"
    return 0
  fi

  if have apk; then
    as_root "apk add --no-cache ansible"
    return 0
  fi

  return 1
}

install_pip() {
  if have python3; then
    if have pip3; then
      pip3 install $PIP_USER ansible
      return 0
    fi
    python3 -m ensurepip >/dev/null 2>&1 || true
    python3 -m pip install --upgrade pip >/dev/null 2>&1 || true
    python3 -m pip install $PIP_USER ansible
    return 0
  fi
  echo "ERROR: python3 not found; cannot install via pip." >&2
  return 1
}

# ---- main
if [ "$METHOD" = "pkg" ]; then
  install_pkg || { echo "Package install failed. Try --method pip" >&2; exit 1; }
elif [ "$METHOD" = "pip" ]; then
  install_pip
else
  # auto: try package manager first, then pip fallback
  install_pkg || install_pip
fi

# Basic verification
if have ansible; then
  echo "Ansible installed: $(ansible --version | head -n 1)"
else
  echo "WARNING: install completed but 'ansible' not found on PATH." >&2
  exit 2
fi