#!/bin/sh

help() { echo "fzf-pm - fzf package manager

USAGE:
	fzf-pkgs [OPTION]... [QUERY]

OPTIONS:
	-g  list global [all] packages
	-l  list local [instllaed] packages (default)
	-i  select and install packages (implies -g)
	-u  select and uninstall packages (implies -l)
	-v  show verbose output
	-h  show this help message

	(for Arch linux only)
	-a AUR_HELPER  specify command for AUR helper

	(special options)
	-s PACKAGE     print package info
	-p             print package manager

	Note: passing global (-g) or local (-l) pkg list will cancel
	any install (-i) or uninstall (-u) operations started previously.

ENVIRONMENT VARIABLES:
	AUR_HELPER    set an AUR helper command for Arch linux

Following package managers are supported:
	apt, pkg, pacman and any pacman compatible AUR helper

QUERY is mandatory when using an AUR Helper" ;}

while getopts 's:gliuha:p' o; do case "$o" in
  s) sflag=0; pkg="$OPTARG" ;;
  g) operation=""; opmsg=""; list_all=0 ;;
  l) operation=""; opmsg=""; list_all=1 ;;
  i) operation="install_pkgs"; opmsg="to Install"; list_all=0 ;;
  u) operation="uninstall_pkgs"; opmsg="to Uninstall"; list_all=1 ;;
  h) help; exit ;;
  a) export AUR_HELPER="$OPTARG" ;;
	p) pflag=0 ;;
  *) printf "fzf-pkgs: invalid option -- '%s'"  "$OPTARG"; exit 1 ;;
esac done
shift $((OPTIND - 1))

if command -v apt-get >> /dev/null; then
	alias pkg_sort='sed -e "s/ - / => /"'

  if [ "$list_all" = 0 ]; then
    export pkg_info='apt-cache show'
    alias list_pkgs='apt-cache search .'
    alias search_pkg='apt-cache search'
  else
    export DPKG_COLOR='always'
    export pkg_info='dpkg-query --status'
    format='${Package} - ${Description}\n'
    alias list_pkgs='dpkg-query --show --showformat "$format"'
    alias search_pkg='dpkg-query --show --showformat "$format" | grep'
  fi

	if command -v pkg >> /dev/null; then
		export PKGMAN="pkg"
		alias install_pkgs='pkg install'
		alias uninstall_pkgs='pkg uninstall'
	else
		export PKGMAN="apt"
		alias install_pkgs='sudo apt-get install'
		alias uninstall_pkgs='sudo apt-get remove'
	fi

elif command -v pacman >> /dev/null; then
	alias pkg_sort='sed -e "N;s/\n\s*/ => /"'

  if [ -n "$AUR_HELPER" ]; then
    export PKGMAN="$AUR_HELPER"
    if command -v "$PKGMAN" >/dev/null; then
      alias install_pkgs='$PKGMAN -S'
      alias uninstall_pkgs='$PKGMAN -Rns'
    else
      echo "fzf-pkgs: AUR Helper '$PKGMAN' command not found" >&2 &&
      exit 1
    fi
  else
    export PKGMAN='pacman'
    alias install_pkgs='sudo $PKGMAN -S'
    alias uninstall_pkgs='sudo $PKGMAN -Rns'
  fi

  if [ "$list_all" = 0 ]; then
    export pkg_info="$PKGMAN --color=always -Si"
    alias list_pkgs='$PKGMAN --color=always -Ss'
    alias search_pkg='$PKGMAN --color=always -Ss'
  else
    export pkg_info="$PKGMAN --color=always -Qi"
    alias list_pkgs='$PKGMAN --color=always -Qs'
    alias search_pkg='$PKGMAN --color=always -Qs'
  fi

else
	echo "fzf-pkgs: package manager not found" >&2
	exit 1
fi

if [ "$pflag" = 0 ]; then
	printf "%s\n" "$PKGMAN"
	exit
elif [ "$sflag" = 0 ]; then
	printf "$ %s '%s'\n" "$pkg_info" "$pkg"
	$pkg_info $pkg
	exit
fi

query="$1"
if [ -n "$AUR_HELPER" ] && [ -z "$query" ] && [ "$list_all" = 0 ]; then
	echo "fzf-pkgs: providing QUERY is mandatory when using an AUR Helper"
	exit 1
	# printf "query: "; read -r query
	# [ -z "$query" ] && exit 1
fi

if [ -n "$query" ]; then
	prompt="searching '$query' "
	get_pkgs() { search_pkg "$query"; }
else
	get_pkgs() { list_pkgs; }
fi

[ -z "$FZF_HISTDIR" ] &&
	export FZF_HISTDIR="${XDG_STATE_HOME:-$HOME/.local/state}/fzf"
mkdir -pv "$FZF_HISTDIR"
export FZF_HIST="$FZF_HISTDIR/package_history"

fzff() {
	preview='
		echo "selected packages:";
		printf "\t%s\n" {+1} | tr " " "\n"
		echo
		eval "$pkg_info 2>/dev/null" {1}
		'
	fzf --ansi --multi \
		--history="$FZF_HIST" \
		--header="Select packages $opmsg" --header-first --prompt="$prompt> " \
		--preview="$preview" --preview-window="hidden" --tiebreak='begin' \
		--bind 'ctrl-v:toggle-preview,ctrl-space:toggle-preview'
}

pkgs="$(get_pkgs | pkg_sort | fzff | cut -d' ' -f1 | tr '\n' ' ')"
[ -n "$pkgs" ] || exit 2
echo "$pkgs"
[ -n "$operation" ] && eval $operation $pkgs