#!/usr/bin/env bash
# Author: Jack L. Frost <fbt@fleshless.org>
# Licensed under the Internet Software Consortium (ISC) license.
# See LICENSE for its text.

_self="${0##*/}"

cfg_workdir="$PWD"
cfg_aur_url='https://aur.archlinux.org'
cfg_aur_api="${cfg_aur_url}/rpc.php"

echo() { printf '%s\n' "$*"; }
err() { echo "$*" >&2; }

_cat() { while read -r; do printf '%s\n' "$REPLY"; done }

usage() {
	_cat <<- EOF
		Usage: $_self [flags] <package>
		Flags:
		        -h        Show this message.
		        -s        Search for <package>.
		          -S        Search only in the sync db. Implies -s.
		          -A        Search only in AUR. Implies -s.
		        -d        Get the package sources (default). Set twice to also get the dependencies.
		          -f        Force downloading package sources even if they are already present in the working directory.
		        -w <dir>  Set the working directory.
	EOF
}

aur.search() {
	declare aur_api_search_data aur_search_result_num aur_search_results version description

	aur_api_search_data=$( curl -skL "${cfg_aur_api}?type=search&arg=${1}" )
	aur_search_result_num=$( jshon -e resultcount -u <<< "$aur_api_search_data" )

	# Exit if nothing was found
	(( aur_search_result_num )) || { return 1; }

	aur_search_results=( $( jshon -e results -a -e Name -u <<< "$aur_api_search_data" ) )

	for i in "${!aur_search_results[@]}"; do
		{
			read -r version
			read -r description
		} < <(
			jshon -e results -e $i -e Version -u -p -e Description -u <<< "$aur_api_search_data"
		)

		printf '%s %s\n    %s\n' "aur/${aur_search_results[$i]}" "$version" "$description"
	done
}

aur.info() {
	declare pkg_aur_info aur_query_result
	
	pkg_aur_info=$( curl -skL "${cfg_aur_api}?type=info&arg=${1}" 2>/dev/null )
	aur_query_result=$( jshon -e resultcount -u <<< "$pkg_aur_info" )

	(( aur_query_result )) || { return 1; }

	echo "$pkg_aur_info"
}

aur.get() {
	declare pkg_aur_info pkg_base tarball_path depends makedepends dep_name aur_api_multireq dep_name aur_deps_api_data aur_deps_count aur_deps
	
	read -r pkg_aur_info

	{
		read -r pkg_base
		read -r tarball_path
	} < <(
		jshon -e results -e PackageBase -u -p -e URLPath -u <<< "$pkg_aur_info"
	)

	(( flag_force )) || {
		[[ -d "${cfg_workdir}/${pkg_base}" ]] && {
			echo "Found ${pkg_base} in ${cfg_workdir}, skipping. Use -f to override."
			return 17
		}
	}

	cd "$cfg_workdir"

	echo "Working in ${cfg_workdir}"

	echo "Downloading ${pkg_base}"
	{ curl -skL "${cfg_aur_url}${tarball_path}" | gzip -d | tar x; } || {
		err "Fail!"
		return 1
	}

	if (( flag_get_deps )); then
		cd "${cfg_workdir}/${pkg_base}"
		source PKGBUILD

		for i in "${depends[@]}" "${makedepends[@]}"; do
			dep_name="${i/[<>=]*}"
			aur_api_multireq+="&arg\[\]=$dep_name"
		done
		
		aur_deps_api_data=$( curl -skL "${cfg_aur_api}?type=multiinfo${aur_api_multireq}" )
		aur_deps_count=$( jshon -e resultcount <<< "$aur_deps_api_data" )

		if (( aur_deps_count )); then
			echo "Getting dependencies for ${pkg_base}."

			aur_deps=( $( jshon -e results -a -e Name -u <<< "$aur_deps_api_data" ) )

			for i in "${aur_deps[@]}"; do
				aur.get < <(aur.info "$i")
				_result="$?"

				(( _result > 0 && result != 17 )) && {
					return "$_result"
				}
			done
		fi
	fi
}

abs.get() {
	declare pkg_repo svn_repo

	pkg_repo="$2"

	case "$pkg_repo" in
		(community|multilib)
			svn_repo='community';;
		(*)
			svn_repo='packages';;
	esac

	svn checkout "svn://svn.archlinux.org/${svn_repo}/${1}/trunk" "${cfg_workdir}/${1}"
}

set_argv() {
	declare arg opt c
	declare -g argv

	while (( $# )); do
		unset -v arg opt c

		case "$1" in
			(--) argv+=( "$1" ); break;;

			(--*)
				IFS='=' read arg opt <<< "$1"
				argv+=( "$arg" )

				[[ "$opt" ]] && {
					argv+=( "$opt" )
				}
			;;

			(-*)
				while read -n1 c
				do
					case "$c" in
						-|'') :;;
						*) argv+=( "-$c" );;
					esac
				done <<< "$1"
			;;

			(*) argv+=( "$1" );;
		esac
		shift
	done
}

main() {
	if [[ -f "$HOME/.config/zpac.rc.sh" ]]; then
		source "$HOME/.config/zpac.rc.sh"
	fi

	while (( $# )); do
		case "$1" in
			(--) shift; break;;

			(-h) usage; return 0;;

			(-s) action='search';;
			(-A)
				action='search'
				flag_search_aur=1;;
			(-S)
				action='search'
				flag_search_syncdb=1;;

			(-d)
				if [[ "$action" == 'get' ]]; then
					flag_get_deps=1
				else
					action='get'
				fi
			;;

			(-w) 
				cfg_workdir="$2"
				shift;;

			(-f) flag_force=1;;

			(-*)
				err "Unknown key: $1"
				usage
				return 1
			;;

			(*) break;;
		esac
		shift
	done

	(( flag_search_aur && flag_search_syncdb )) && {
		unset flag_search_aur flag_search_syncdb
	}

	[[ "$action" ]] || {
		usage
		return 1
	}

	if [[ "$1" ]]; then
		package="$1"
	else
		usage
		return 1
	fi

	case "$action" in
		(get)
			[[ -d "$cfg_workdir" ]] || {
				mkdir -p "$cfg_workdir" || {
					err "Can't create workdir: ${cfg_workdir}."
					return 1
				}
			}

			pkg_aur_info=$( aur.info "$package" )

			if (( ! "$?" )); then
				repo='aur'
			else
				while read -r; do
					if [[ "$REPLY" =~ ^Repository ]]; then
						repo="${REPLY##* }"
					fi
				done < <( pacman -Si "$package" )

				[[ "$repo" ]] || {
					err "Can't find package ${package}"
					return 1
				}
			fi

			echo "Found ${package} in ${repo}."

			case "$repo" in
				(aur)
					aur.get <<< "$pkg_aur_info";;

				(core|extra|community|multilib)
					abs.get "$package" "$repo";;

				(*)
					err "Repository $repo not supported."
					return 1;;
			esac
		;;

		(search)
			if (( flag_search_aur )); then
				aur.search "$package" || {
					err "No packages found."
					return 1
				}
			elif (( flag_search_syncdb )); then
				pacman -Ss "$package"
			else
				aur.search "$package" || { flag_aur_search_fail=1; }
				pacman -Ss "$package" 2>/dev/null || { flag_pacman_search_fail=1; }

				if (( flag_aur_search_fail && flag_pacman_search_fail )); then
					err "No packages found."
					return 1
				fi
			fi
		;;
	esac
}

set_argv "$@"
main "${argv[@]}"