#!/usr/bin/env bash
set +xve

VERSION="v1.0.4"
INSTALL="no"
SKIP_INSTALLED="no"
declare -a CORE_PACKAGES=()
declare -a OPTIONAL_PACKAGES=()
declare -a PACKAGES_EXCLUDED=()

display_help() {
  echo ""
  echo "USAGE:"
  echo "  optional-packages [OPTIONS] <PACKAGE-1> <PACKAGE-2> <…>"
  echo ""
  echo "DESCRIPTION"
  echo "  Command-line tool that finds all the optional packages of the packages that"
  echo "  were pointed by you. It has different options to filter these packets."
  echo "  Beyond that, you can install the packages you pointed to the dependencies and"
  echo "  the optional packages you found and filtered."
  echo ""
  echo "ARGS:"
  echo "  The name of the packages separate by spaces."
  echo "  <PACKAGE-1> <PACKAGE-2> <…>"
  echo ""
  echo "OPTIONS:"
  echo "  ┌──────┬──────────────────┬──────────────────────────────────────────────────┐"
  echo "  │ Abbr │       Long       │                     Information                  │"
  echo "  ╞══════╪══════════════════╪══════════════════════════════════════════════════╡"
  echo "  │  -e  │ --exclude        │ Excludes packages mentioned during a deep search.│"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     string                             │"
  echo "  │      │                  │   - Values:   package-1 package-2 …              │"
  echo "  │      │                  │   - Default:  none                               │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -h  │ --help           │ Display information for this command and exit.   │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     none                               │"
  echo "  │      │                  │   - Values:   none                               │"
  echo "  │      │                  │   - Default:  none                               │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -i  │ --install        │ Install all the packages found.                  │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     boolean                            │"
  echo "  │      │                  │   - Values:   yes | no                           │"
  echo "  │      │                  │   - Default:  no                                 │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -p  │ --packages       │ The core packages from which to start the search │"
  echo "  │      │                  │ for optional packages.                           │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     string                             │"
  echo "  │      │                  │   - Values:   package-1 package-2 …              │"
  echo "  │      │                  │   - Default:  none                               │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -s  │ --skip-installed │ Skip the installed packages.                     │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     boolean                            │"
  echo "  │      │                  │   - Values:   yes | no                           │"
  echo "  │      │                  │   - Default:  no                                 │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │  -V  │ --version        │ Display the version of this tool along with the  │"
  echo "  │      │                  │ project information and exit.                    │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     none                               │"
  echo "  │      │                  │   - Values:   none                               │"
  echo "  │      │                  │   - Default:  none                               │"
  echo "  ├──────┼──────────────────┼──────────────────────────────────────────────────┤"
  echo "  │      │ --version-simple │ Display the version of this tool and exit.       │"
  echo "  │      │                  │   - Required: no                                 │"
  echo "  │      │                  │   - Type:     none                               │"
  echo "  │      │                  │   - Values:   none                               │"
  echo "  │      │                  │   - Default:  none                               │"
  echo "  └──────┴──────────────────┴──────────────────────────────────────────────────┘"
  echo ""
  echo "  Note: Multiple values are separated by spaces."
  echo ""
  echo "EXAMPLES:"
  echo "  - Search for three packages."
  echo "    - Commands:"
  echo "        optional-packages bash lsd rust"
  echo "        optional-packages -p bash lsd rust"
  echo "        optional-packages --packages bash lsd rust"
  echo ""
  echo "  - Search for a package, but exclude some optional packages."
  echo "    - Commands:"
  echo "        optional-packages -p kitty -e imagemagick python-pygments"
  echo "        optional-packages -packages kitty -exclude imagemagick python-pygments"
  echo ""
  echo "  - Install the core packages and any additional packages found."
  echo "    - Commands:"
  echo "        optional-packages -p lsd -i yes"
  echo "        optional-packages -packages lsd --install yes"
  echo ""
  echo "  - Search for optional packages, just for any core packages or optional"
  echo "    packages that are not installed."
  echo "    - In this case, 'lsd' is already installed, it will not look for any"
  echo "      optional dependencies because it is already installed."
  echo "    - Otherwise, if the value of this option is 'no' (the default value), then"
  echo "      it would look for dependencies on the 'lsd' package or any package."
  echo "    - Commands:"
  echo "        optional-packages -p lsd -s yes"
  echo "        optional-packages -packages lsd --skip-installed yes"
  echo ""
  echo "  - All words at the end of the command are considered core packages. In this"
  echo "    example are 'bash lsd rust'."
  echo "    - Commands:"
  echo "        optional-packages bash lsd rust"
  echo "        optional-packages --install yes bash lsd rust"
  echo "        optional-packages --exclude bat --install yes bash lsd rust"
  echo "    - Warning: if your last option is 'exclude', all words at the end count as"
  echo "      exclusion and not for parent packages. In this case, nothing will be"
  echo "      installed because no parent package was pointed to."
  echo "        optional-packages --install yes --exclude bat bash lsd rust"
  echo ""
  echo "  - Multiple options can be used multiple times, plus core packages can be at"
  echo "    the end."
  echo "    - In this example, it will search for optional packages within the following"
  echo "      core packages 'lsd kitty virtualbox bat xterm'; exclude 'python gtk3 perl'"
  echo "      optional packages; avoid installed packages; and finally, install the"
  echo "      packages found."
  echo "    - Note: For options that have a single value (boolean), when the same option"
  echo "      is entered multiple times, it will take the last option and its value. The"
  echo "      order matters."
  echo "    - Commands:"
  echo "        optional-packages -s no -p lsd kitty -s yes -e python gtk3 \\"
  echo "                          -p virtualbox -e perl -i no -i yes bat xterm"
  echo ""
  display_version
  echo ""
  echo ""
}

display_version() {
  echo "VERSION:"
  echo "  ${VERSION}"
  echo ""
  echo "  Source: https://github.com/airvzxf/archlinux-optional-packages/"
  echo "  Author: Israel Roldan"
  echo "    Email: israel.alberto.rv@gmail.com"
  echo "    GitHub: @airvzxf"
  echo "    Twitter: @IsraelAlbert_RV"
  echo "    Website: https://www.rovisoft.net/"
}

display_version_simple() {
  echo "${VERSION}"
}

parse_arguments() {
  while [[ ${#} -gt 0 ]]; do
    case "${1}" in
      -e | --exclude)
        # Remove this argument.
        shift
        local value
        for value in "${@}"; do
          if [[ ${value} == -* ]]; then
            break
          fi
          PACKAGES_EXCLUDED+=("${1}")
          # Remove this value.
          shift
        done
        ;;
      -h | --help)
        display_help
        exit 0
        ;;
      -i | --install)
        # Remove this argument.
        shift
        INSTALL="${1}"
        # Remove this value.
        shift
        ;;
      -p | --packages)
        # Remove this argument.
        shift
        local value
        for value in "${@}"; do
          if [[ ${value} == -* ]]; then
            break
          fi
          CORE_PACKAGES+=("${1}")
          # Remove this value.
          shift
        done
        ;;
      -s | --skip-installed)
        # Remove this argument.
        shift
        SKIP_INSTALLED="${1}"
        # Remove this value.
        shift
        ;;
      -V | --version)
        display_version
        exit 0
        ;;
      --version-simple)
        display_version_simple
        exit 0
        ;;
      --* | -*)
        echo "Unknown option ${1}."
        echo "Review the help with this command:"
        echo "  optional-packages -h"
        exit 1
        ;;
      *)
        # Any argument without an option must be a package.
        CORE_PACKAGES+=("${1}")
        # Remove past argument.
        shift
        ;;
    esac
  done
}

is_none_optional_dependencies() {
  local package
  package="${1}"

  local optional_dependencies
  optional_dependencies=$(
    pacman --sync --info "${package}" |
      grep --extended-regexp "^Optional Deps\s+:\s+None$" ||
      return 0
  )

  if [[ -z ${optional_dependencies} ]]; then
    # False: It has optional dependencies
    return 1
  fi

  # True: It has none optional dependencies
  return 0
}

search_optional_dependencies() {
  echo "# --------------------"
  local package
  package="${1}"
  echo "package: ${package}"

  if [[ ${SKIP_INSTALLED} == "yes" ]]; then
    pacman --query --info "${package}" 1> /dev/null 2>&1 && {
      echo "Skip: ${package} is installed."
      return 0
    }
  fi

  local package_excluded
  for package_excluded in "${PACKAGES_EXCLUDED[@]}"; do
    if [[ ${package_excluded} == "${package}" ]]; then
      echo "Skip: ${package} is excluded."
      return 0
    fi
  done

  local avoid_core_packages
  avoid_core_packages="${2}"
  if [[ -z ${avoid_core_packages} ]]; then
    OPTIONAL_PACKAGES+=("${package}")
  fi

  if is_none_optional_dependencies "${package}"; then
    echo "Skip: ${package} has none optional dependencies."
    # True: Finish the function.
    return 0
  fi

  local optional_dependencies
  optional_dependencies=$(
    pacman --sync --info "${package}" |
      sed --silent '/^Optional Deps/,$p' |
      sed '/^Conflicts/q' | head --lines -1 |
      sed --regexp-extended 's/Optional Deps\s+:\s+//g' |
      sed --regexp-extended 's/^\s+//g' |
      sed --regexp-extended 's/:.*//g' |
      tr '\n' ' ' |
      sed --regexp-extended 's/\s+$//g' ||
      return 0
  )

  local packages
  read -ra packages <<< "$optional_dependencies"

  local dependency
  for dependency in "${packages[@]}"; do
    echo "${package} ➟ ${dependency}"
    local package_in_the_list
    package_in_the_list=false

    local package_added
    for package_added in "${OPTIONAL_PACKAGES[@]}"; do
      if [[ ${dependency} == "${package_added}" ]]; then
        package_in_the_list=true
        echo "Skip: ${package} ➟ ${dependency}. It is in the list of optional dependencies."
        break
      fi
    done

    if [[ ${package_in_the_list} == false ]]; then
      search_optional_dependencies "${dependency}"
    fi
  done
}

set_optional_dependencies() {
  local package
  local -i index=1
  for package in "${CORE_PACKAGES[@]}"; do
    echo "# --------------------------------------"
    echo "Core package #${index}/${#CORE_PACKAGES[@]}: ${package}"
    search_optional_dependencies "${package}" "avoid_core_packages"
    echo "Optional packages: |-${OPTIONAL_PACKAGES[*]}-|"
    index+=1
  done
  echo "# --------------------------------------"
  echo "Optional packages: |-${OPTIONAL_PACKAGES[*]}-|"
}

install_packages() {
  echo "# --------------------------------------"
  if [[ ${INSTALL} == "yes" ]]; then
    if [[ -n ${CORE_PACKAGES[*]} ]]; then
      # shellcheck disable=SC2048,SC2086
      sudo pacman --sync --needed --noconfirm ${CORE_PACKAGES[*]}
    fi
    if [[ -n ${OPTIONAL_PACKAGES[*]} ]]; then
      # shellcheck disable=SC2048,SC2086
      sudo pacman --sync --asdeps --needed --noconfirm ${OPTIONAL_PACKAGES[*]}
    fi
  fi
}

main() {
  parse_arguments "${@}"

  echo "# ----------------------"
  echo "CORE_PACKAGES      = ${CORE_PACKAGES[*]}"
  echo "PACKAGES_EXCLUDED  = ${PACKAGES_EXCLUDED[*]}"
  echo "INSTALL            = ${INSTALL}"
  echo "SKIP_INSTALLED     = ${SKIP_INSTALLED}"

  set_optional_dependencies

  install_packages
  echo "# --------------------------------------"
}

main "${@}"