install

#!/bin/sh
# SPDX-License-Identifier: GPL-3.0-only
#
# This file is part of the smux project: https://github.com/tomeichlersmith/smux
#
# Copyright (C) 2021 smux contributors
#
# smux is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 3
# as published by the Free Software Foundation.
#
# smux is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with smux; if not, see <http://www.gnu.org/licenses/>.

# POSIX
set -o errexit
set -o nounset

# Print usage to stdout.
# Arguments:
#   None
# Outputs:
#   print usage with examples.
show_help() {
  cat << EOF
install --prefix /usr/local

Options:
  --prefix/-p:    base bath where all files will be deployed (default /usr/local if root, ~/.local if not)
  --devel/-d:   symlink to install location rather than copy, helpful for testing during development
                ignored if not in the repository
  --next/-n:    install HEAD of main branch rather than last release
  --help/-h:    show this message
  -v:     show more verbosity
EOF
}

version=v1.0.1
next=0
verbose=0
devel=0
prefix=""

# Parse arguments
while [ "$#" -gt 0 ]; do
  case $1 in
    -h | --help)
      # Call a "show_help" function to display a synopsis, then exit.
      show_help
      exit
      ;;
    -v | --verbose)
      shift
      verbose=1
      ;;
    -d | --devel)
      shift
      devel=1
      ;;
    -n | --next)
      shift
      next=1
      ;;
    -p | --prefix)
      if [ -n "$2" ]; then
        prefix="$2"
        shift
        shift
      fi
      ;;
    *) # Default case: If no more options then break out of the loop.
      break ;;
  esac
done

# set verbosity
if [ "${verbose}" -ne 0 ]; then
  set -o xtrace
fi

if  [ -z "${prefix}" ]; then
  prefix="/usr/local"
  # in case we're not root, just default to the home directory
  if [ "$(id -u || true)" -ne 0 ]; then
    prefix="${HOME}/.local"
  fi
fi
completion_dest_path="${prefix}/share/bash-completion/completions/"
dest_path="${prefix}/bin"
man_dest_path="${prefix}/share/man/man1"

# get current dir
curr_dir=$(dirname "$0")
cd "${curr_dir}" || exit 1

# if files are available, install files in dest directory
if [ -e "${curr_dir}/smux" ]; then
  if [ "${devel}" -ne 0 ]; then
    copy="ln -sf -t"
    if ! ${copy} "${dest_path}" "${PWD}/smux"; then
      printf >&2 "Do you have permission to write to %s?\n" "${dest_path}"
      exit 1
    fi
  else
    copy="install -D -m 0644 -t"
    if ! install -D -m 0755 -t "${dest_path}" smux; then
      printf >&2 "Do you have permission to write to %s?\n" "${dest_path}"
      exit 1
    fi
  fi
  if [ -e "man" ]; then
    for file in "${PWD}"/man/man1/*; do
      ${copy} "${man_dest_path}" "${file}"
    done
  fi
  if [ -e "completions" ]; then
    for file in "${PWD}"/completions/*; do
      ${copy} "${completion_dest_path}" "${file}"
    done
  fi
else
  printf >&2 "\033[1;31m Checking dependencies...\n\033[0m"
  # check that we have base dependencies
  if ! { command -v curl > /dev/null || command -v wget > /dev/null; } || ! command -v tar > /dev/null; then
    printf >&2 "Online install depends on tar and either curl or wget\n"
    printf >&2 "Ensure you have all dependencies installed.\n"
    exit 1
  fi

  if command -v curl > /dev/null 2>&1; then
    download="curl -sLo"
  elif command -v wget > /dev/null 2>&1; then
    download="wget -qO"
  fi

  printf >&2 "\033[1;31m Downloading...\n\033[0m"
  if [ "${next}" -eq 0 ]; then
    release_ver="tomeichlersmith/smux/archive/refs/tags/${version}.tar.gz"
    release_name=$(echo "${release_ver}" | grep -Eo '[0-9]+\.[0-9]+\.[0-9]+\.tar\.gz$')
  else
   release_ver="tomeichlersmith/smux/archive/refs/heads/main.tar.gz"
   release_name="main"
  fi
  # go in tmp
  tmp_dir="$(mktemp -d)"
  cd "${tmp_dir}"
  # download our target
  ${download} "${release_name}" "https://github.com/${release_ver}"
  # uncompress
  printf >&2 "\033[1;31m Unpacking...\n\033[0m"
  if [ "${verbose}" -ne 0 ]; then
    tar xvf "${release_name}"
  else
    tar xf "${release_name}"
  fi
  # enter source
  cd "smux-$(echo "${release_name}" | sed 's|.tar.gz||' || true)"

  # deploy
  copy="install -D -m 0644 -t"
  if ! install -D -m 0755 -t "${dest_path}" smux; then
    printf >&2 "Do you have permission to write to %s?\n" "${dest_path}"
    exit 1
  fi
  if [ -e "man" ]; then
    for file in "${PWD}"/man/man1/*; do
      ${copy} "${man_dest_path}" "${file}"
    done
  fi
  if [ -e "completions" ]; then
    for file in "${PWD}"/completions/*; do
      ${copy} "${completion_dest_path}" "${file}"
    done
  fi

  # securely delete unneeded files
  cd
  if [ -n "${tmp_dir}" ] && [ -e "${tmp_dir}" ]; then
    rm -rf "${tmp_dir}"
  fi
fi

[ ! -w "${dest_path}" ] && printf >&2 "Cannot write into %s, permission denied.\n" "${dest_path}" && exit 1
[ ! -w "${man_dest_path}" ] && printf >&2 "Cannot write into %s, permission denied.\n" "${man_dest_path}" && exit 1

printf >&2 "\033[1;31m Successfully installed to %s.\n\033[0m" "${dest_path}"
case "${PATH}" in
  *"${dest_path}"*)
    if [ "${verbose}" -ne 0 ]; then
      printf >&2  "  Found %s in PATH\n" "${dest_path}"
    fi
    ;;
  *)
    printf >&2 "\033[1;31m Unable to find %s in PATH.\n\033[0m" "${dest_path}"
    printf >&2 "\033[1;31m Be sure that %s is in your \$PATH environment variable for smux to work.\n\033[0m" "${dest_path}"
    ;;
esac