#!/bin/sh
#
#  scratchpkg
#
#  Copyright (c) 2018 by Emmett1  (emmett1.2miligrams@gmail.com)
#
#  This program is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.
#

msg() {
	echo "==> $1"
}

msg2() {
	echo " -> $1"
}

msgerr() {
	echo "==> ERROR: $1"
}

msgwarn() {
	echo "==> WARNING: $1"
}

updatemdsum() {
	msg "Generating .checksums..."
	generatemdsum > .checksums
}

generatemdsum() {	
	if [ -z "$source" ]; then
		echo SKIP
		return 0
	fi
	
	for src in $source; do
		if echo $src | grep -qE "::(ftp|http|https)://"; then
			FILENAME=$SOURCE_DIR/$(echo $src | awk -F '::' '{print $1}')
		elif echo $src | grep -qE "(ftp|http|https)://"; then
			FILENAME=$SOURCE_DIR/$(basename $src)
		else
			FILENAME=$src
		fi
		needupdatechecksum="$needupdatechecksum $FILENAME"
	done
	
	md5sum $needupdatechecksum | sed -e 's|  .*/|  |' | sort -k 2
}

checkmdsum() {	
	TMPCHECKSUM=$WORK_DIR/checksumstmp.$$
	ORICHECKSUM=$WORK_DIR/checksumsori.$$
	DIFCHECKSUM=$WORK_DIR/checksumsdiff.$$
	
	if [ ! -f .checksums ]; then
		msg "Generating .checksums..."
		generatemdsum > .checksums
	else
		msg "Checking checksums..."
		generatemdsum > "$TMPCHECKSUM"
		sort -k2 .checksums > "$ORICHECKSUM"
		diff -w -t -U 0 "$ORICHECKSUM" "$TMPCHECKSUM" > "$DIFCHECKSUM"
	fi
	
	[ -s "$DIFCHECKSUM" ] && {
		mismatch=1
		cat "$DIFCHECKSUM" \
		| sed '/---/d' \
		| sed '/+++/d' \
		| sed '/@@/d' \
		| sed 's/^-/ -> missing: /' \
		| sed 's/^+/ -> new    : /'
	}
	
	rm -f "$TMPCHECKSUM" "$DIFCHECKSUM" "$ORICHECKSUM"
	
	[ "$mismatch" = 1 ] && abort 1
}

download_src() {	
	for FILE in $source; do
		if echo $FILE | grep -Eq '::(http|https|ftp)://'; then
			FILENAME=$(echo $FILE | awk -F '::' '{print $1}')
			SRCURL=$(echo $FILE | awk -F '::' '{print $2}')
		else
			FILENAME=$(basename $FILE)
			SRCURL=$FILE
		fi
		[ "$DOWNLOAD_PROG" = "auto" ] && {
			command -v curl >/dev/null && DOWNLOAD_PROG=curl
			command -v wget >/dev/null && DOWNLOAD_PROG=wget
		}
		case $DOWNLOAD_PROG in
			curl) DLCMD="curl -C - -L --fail --ftp-pasv --retry 3 --retry-delay 3 -o $SOURCE_DIR/$FILENAME.partial $CURL_OPTS" ;;
			wget) DLCMD="wget -c --passive-ftp --no-directories --tries=3 --waitretry=3 --output-document=$SOURCE_DIR/$FILENAME.partial $WGET_OPTS" ;;
			*) msgerr "No download agent found"; abort 1;;
		esac
		if [ "$FILENAME" != "$FILE" ]; then
			if [ ! -f "$SOURCE_DIR/$FILENAME" ] || [ "$REDOWNLOAD_SOURCE" ]; then
				[ "$REDOWNLOAD_SOURCE" ] && rm -f "$SOURCE_DIR/$FILENAME.partial"
				if [ -f "$SOURCE_DIR/$FILENAME.partial" ]; then
					msg "Resuming '$SRCURL'."
				else
					msg "Downloading '$SRCURL'."
				fi
				$DLCMD $SRCURL
				if [ $? = 0 ]; then
					[ "$REDOWNLOAD_SOURCE" ] && rm -f "$SOURCE_DIR/$FILENAME"
					mv $SOURCE_DIR/$FILENAME.partial $SOURCE_DIR/$FILENAME
				else
					msgerr "Failed downloading '$FILENAME'."
					abort 1
				fi
			fi
		else
			if [ ! -f "$FILENAME" ]; then
				msgerr "Source '$FILENAME' not found."
				abort 1
			fi
		fi
	done
}

prepare_src() {	
	[ "$IGNORE_MDSUM" -o "$CHECK_MDSUM" = 0 ] || checkmdsum
	
	SRC=$WORK_DIR/$name/src
	PKG=$WORK_DIR/$name/pkg
	
	umask 022
	
	rm -fr $WORK_DIR/$name
	
	mkdir -p $SRC $PKG
	
	if [ "$source" ]; then
		for FILE in $source; do
			if echo $FILE | grep -Eq '::(http|https|ftp)://'; then
				FILENAME=$SOURCE_DIR/$(echo $FILE | awk -F '::' '{print $1}')
			elif echo $FILE | grep -Eq '^(http|https|ftp)://'; then
				FILENAME=$SOURCE_DIR/$(basename $FILE)
			else
				FILENAME=$PWD/$(basename $FILE)
			fi
			for NOEXT in $noextract; do
				if [ "$NOEXT" = "$(basename $FILENAME)" ]; then
					nxt=1
					break
				fi
			done
			if [ "$FILENAME" != "$FILE" ] && [ "$nxt" != 1 ]; then
				case $FILENAME in
					*.tar|*.tar.gz|*.tar.Z|*.tgz|*.tar.bz2|*.tbz2|*.tar.xz|*.txz|*.tar.lzma|*.zip|*.rpm)
						if [ $(command -v bsdtar) ]; then
							COMMAND="bsdtar -p -o -C $SRC -xf $FILENAME"
						else
							COMMAND="tar -p -o -C $SRC -xf $FILENAME"
						fi
						MODE="Unpacking" ;;
					*)
						COMMAND="cp $FILENAME $SRC"
						MODE="Preparing" ;;				
				esac
				msg "$MODE '$(basename $FILENAME)'..."
				$COMMAND || {
					msgerr "$MODE '$FILENAME' failed."
					abort 1
				}
			else
				MODE="Preparing"
				msg "$MODE '$(basename $FILENAME)'..."
				cp "$FILENAME" "$SRC" || {
					msgerr "$MODE '$FILENAME' failed."
					abort 1
				}
			fi
			unset nxt
		done
	fi
}

run_build() {	
	[ "$(id -u)" = 0 ] || {
		msgerr "You must build package as root, or use fakeroot."
		abort 1
	}
	
	msg "Start build '$name-$version-$release'."	
	
	[ "$MAKE_FLAGS" = 1 ]  && export MAKEFLAGS       || unset MAKEFLAGS
	[ "$BUILD_FLAGS" = 1 ] && export CFLAGS CXXFLAGS || unset CFLAGS CXXFLAGS
	
	cd $SRC >/dev/null
	
	(set -e -x; build 2>&1)
		
	if [ $? != 0 ]; then
		msgerr "Build '$name-$version-$release' failed."
		abort 1
	else
		msg "Build '$name-$version-$release' success."
	fi
	
	cd - >/dev/null
}

removeemptydirs() {	
	find . -type d -empty -delete	
}

removelibtool() {	
	find . ! -type d -name "*.la" -delete
}

strip_files() {	
	if [ "$nostrip" ]; then
		for i in $nostrip; do
			xstrip="$xstrip -e $i"
		done
		FILTER="grep -v $xstrip"
	else
		FILTER="cat"
	fi
			
	find . -type f -printf "%P\n" 2>/dev/null | $FILTER | while read -r binary ; do
		case "$(file -bi "$binary")" in
			*application/x-sharedlib*)  # Libraries (.so)
				strip --strip-unneeded "$binary" 2>/dev/null ;;
			*application/x-pie-executable*)  # Libraries (.so)
				strip --strip-unneeded "$binary" 2>/dev/null ;;
			*application/x-archive*)    # Libraries (.a)
				strip --strip-debug "$binary" 2>/dev/null ;;
			*application/x-object*)
				case "$binary" in
					*.ko)                   # Kernel module
						strip --strip-unneeded "$binary" 2>/dev/null ;;
					*)
						continue;;
				esac;;
			*application/x-executable*) # Binaries
				strip --strip-all "$binary" 2>/dev/null ;;
			*)
				continue ;;
		esac
	done
}

compressinfomanpages() {
	find . -type f -path "*/man/man*/*" | while read -r file; do
		if [ "$file" = "${file%%.gz}" ]; then
			gzip -9 -f "$file"
		fi
	done
	find . -type l -path "*/man/man*/*" | while read -r file; do
		FILE="${file%%.gz}.gz"
		TARGET="$(readlink $file)"
		TARGET="${TARGET##*/}"
		TARGET="${TARGET%%.gz}.gz"
		DIR=$(dirname "$FILE")
		rm -f $file
		if [ -e "$DIR/$TARGET" ]; then
			ln -sf $TARGET $FILE
		fi
	done
	if [ -d usr/share/info ]; then
		(cd usr/share/info
			for file in $(find . -type f); do
				if [ "$file" = "${file%%.gz}" ]; then
					gzip -9 "$file"
				fi
			done
		)
	fi
}

backupconf() {
	for FILE in $backup; do
		if [ ! -f $FILE ]; then
			msgerr "File '$FILE' not exist!"
			abort 1
		else
			mv $FILE $FILE.spkgnew
		fi
	done
}

removedocs() {
	for i in doc gtk-doc info; do
		rm -fr \
			usr/share/$i \
			usr/$i \
			usr/local/$i \
			usr/local/share/$i
	done
}

removelocales() {
	rm -fr \
		usr/share/locale \
		usr/locale \
		usr/local/locale \
		usr/local/share/locale \
		usr/lib/locale
}

packaging() {
	for FILE in $INCLUDEINPKG; do
		if [ -f $FILE ]; then
			install -m644 $FILE $PKG/.pkg$FILE
			addtotar="$addtotar .pkg$FILE"
		fi
	done
	
	cd $PKG >/dev/null
	
	# remove possible conflict junks
	rm -f usr/share/info/dir usr/info/dir
	rm -f usr/lib/charset.alias # on musl system
	find . \( -name perllocal.pod -o -name .packlist \) -delete
	[ -d usr/share/fonts ] && {
		find usr/share/fonts \( -name fonts.dir -o -name fonts.scale \) -delete
	}
	
	# remove pseudo directories
	#rm -fr dev sys proc run tmp
	
	[ "$KEEP_EMPTYDIR" = 0 ] && removeemptydirs
	[ "$KEEP_LIBTOOL" = 0 ]  && removelibtool
	[ "$STRIP_BINARY" = 1 ]  && strip_files
	[ "$ZIP_MAN" = 1 ]       && compressinfomanpages
	[ "$KEEP_DOCS" = 0 ]     && removedocs
	[ "$KEEP_LOCALES" = 0 ]  && removelocales
	
	if [ "${#backup[@]}" -gt 0 ]; then
		backupconf
	fi
	
	[ "$FORCE_REBUILD" ] && rm -f "$PACKAGE_DIR/$PKGNAME"
	
	case $COMPRESSION_MODE in
		xz) COMPRESS="-J" ;;
		gz) COMPRESS="-z" ;;
		bz2) COMPRESS="-j" ;;
	esac
	
	tar -c $COMPRESS -f $PACKAGE_DIR/$PKGNAME * $addtotar || {
		rm -f $PACKAGE_DIR/$PKGNAME
		msgerr "Packaging '$PKGNAME' failed."
		abort 1
	}
	
	tar -tvf $PACKAGE_DIR/$PKGNAME | sort -k 6
	
	msg "Successfully created package '$PKGNAME'. ($(ls -lh $PACKAGE_DIR/$PKGNAME | awk '{print $5}'))"
		
	cd - >/dev/null
	
	[ -f .pkgfiles ] || generate_pkgfiles
}

generate_pkgfiles() {
	[ -f "$PACKAGE_DIR/$PKGNAME" ] || {
		msgerr "Package '$PKGNAME' not found."
		exit 1
	}
	
	for i in $INCLUDEINPKG; do
		excludefile="$excludefile --exclude=.pkg$i"
	done
	
	msg "Generating .pkgfiles..."
	tar -tvf "$PACKAGE_DIR/$PKGNAME" $excludefile \
	| awk '{$3=$4=$5=""; print $0}' \
	| sed "s,lib/modules/$(uname -r),lib/modules/<kernelversion>,g" \
	| sort -k 3 > .pkgfiles
}

cleanup() {
	[ -e "$PACKAGE_DIR/$PKGNAME" ] && {
		msg "Removing $PACKAGE_DIR/$PKGNAME"
		rm -f "$PACKAGE_DIR/$PKGNAME"
	}
	for src in $source; do
		if echo $src | grep -qE "::(ftp|http|https)://"; then
			FILENAME=$SOURCE_DIR/$(echo $src | awk -F '::' '{print $1}')
		elif echo $src | grep -qE "^(ftp|http|https)://"; then
			FILENAME=$SOURCE_DIR/$(basename $src)
		else
			FILENAME=$src
		fi
		if [ -e "$FILENAME" ] && [ "$FILENAME" != "$src" ]; then
			msg "Removing $FILENAME"
			rm -f "$FILENAME"
		fi
	done
}

check_buildscript() {	
	# check the required field in buildscript
	if [ -z "$name" ]; then
		msgerr "'name' is empty!"
		exit 1
	elif [ "$(basename $(pwd))" != "$name" ]; then
		msgerr "Port name and Directory name is different!"
		exit 1
	elif [ -z "$version" ]; then
		msgerr "'version' is empty!"
		exit 1
	elif [ -z "$release" ]; then
		msgerr "'release' is empty!"
		exit 1
	elif [ ! "$(command -v build)" ]; then
		msgerr "'build' function not exist!"
		exit 1
	elif echo "$version" | grep -q '-'; then
		msgerr "'version' should not contain '-'."
		exit 1
	elif echo "$release" | grep -q '-'; then
		msgerr "'release' should not contain '-'."
		exit 1
	elif [ -z "$description" ]; then
		msgerr "'description' cant empty."
		exit 1
	fi
}

set_options() {	
	for OPT in $OPTIONS $options; do
		case $OPT in
			libtool)     KEEP_LIBTOOL=1 ;;
			!libtool)    KEEP_LIBTOOL=0 ;;
			emptydirs)   KEEP_EMPTYDIR=1;;
			!emptydirs)  KEEP_EMPTYDIR=0;;
			strip)       STRIP_BINARY=1 ;;
			!strip)      STRIP_BINARY=0 ;;
			zipman)      ZIP_MAN=1      ;;
			!zipman)     ZIP_MAN=0      ;;
			buildflags)  BUILD_FLAGS=1  ;;
			!buildflags) BUILD_FLAGS=0  ;;
			makeflags)   MAKE_FLAGS=1   ;;
			!makeflags)  MAKE_FLAGS=0   ;;
			checksum)    CHECK_MDSUM=1  ;;
			!checksum)   CHECK_MDSUM=0  ;;
			docs)        KEEP_DOCS=1    ;;
			!docs)       KEEP_DOCS=0    ;;
			locales)     KEEP_LOCALES=1 ;;
			!locales)    KEEP_LOCALES=0 ;;
		esac
	done
}

checkdir() {
	for DIR in "$@"; do
		if [ ! -d $DIR ]; then
			msgerr "Directory '$DIR' not exist."
			exit 1
		elif [ ! -w $DIR ]; then
			msgerr "Directory '$DIR' not writable."
			exit 1
		elif [ ! -x $DIR ] || [ ! -r $1 ]; then
			msgerr "Directory '$DIR' not readable."
			exit 1
		fi
	done
}

clearworkdir() {
	if [ ! "$KEEP_WORK" ]; then
		if [ "$name" ]; then
			rm -fr $WORK_DIR/$name
		fi
	fi
}

interrupted() {
	echo
	abort 100
}

abort() {
	rm -f "$LOCK_FILE"
	clearworkdir
	exit $1
}

parse_opts() {	
	while [ "$1" ]; do
		case $1 in
		-i |           --install) INSTALL_PKG=yes ;;
		-u |           --upgrade) UPGRADE_PKG=yes; OPTS="$OPTS $1" ;;
		-r |         --reinstall) REINSTALL_PKG=yes; OPTS="$OPTS $1" ;;
		-c |   --ignore-conflict) OPTS="$OPTS $1" ;;
		-v |           --verbose) OPTS="$OPTS $1" ;;
		-f |     --force-rebuild) FORCE_REBUILD=yes ;;
		-m |        --skip-mdsum) IGNORE_MDSUM=yes ;;
		-g |          --genmdsum) UPDATE_MDSUM=yes ;;
		-o |          --download) DOWNLOAD_ONLY=yes ;;
		-x |           --extract) EXTRACT_ONLY=yes ;;
		-w |         --keep-work) KEEP_WORK=yes ;;
		-p |          --pkgfiles) GENPKGFILES=yes ;;
		-h |              --help) SHOWHELP=yes ;;
		                 --clean) CLEANUP=yes ;;
		                --root=*) OPTS="$OPTS $1" ;;
		         --no-preinstall) OPTS="$OPTS $1" ;;
		        --no-postinstall) OPTS="$OPTS $1" ;;
		         --no-preupgrade) OPTS="$OPTS $1" ;;
		        --no-postupgrade) OPTS="$OPTS $1" ;;
		             --no-backup) OPTS="$OPTS $1" ;;
		            --redownload) REDOWNLOAD_SOURCE=yes ;;
		              --config=*) PKGBUILD_CONF="${1#*=}" ;;
		              --srcdir=*) CUSTOM_SOURCE_DIR="${1#*=}" ;;
		              --pkgdir=*) CUSTOM_PACKAGE_DIR="${1#*=}" ;;
		             --workdir=*) CUSTOM_WORK_DIR="${1#*=}" ;;
		                       *) msg "Invalid $(basename $0) option! ($1)"; exit 1 ;;
		esac
		shift
	done	
}

help() {	
	cat << EOF
Usage:
  $(basename $0) [ <options> <arguments> ]

Options:
  -i, --install             install package into system
  -u, --upgrade             upgrade package
  -r, --reinstall           reinstall package
  -c, --ignore-conflict     ignore conflict when installing package
  -v, --verbose             verbose install process
  -f, --force-rebuild       rebuild package
  -m, --skip-mdsum          skip md5sum checking
  -g, --genmdsum            generate md5sum
  -o, --download            download only source file
  -x, --extract             extract only source file
  -p, --pkgfiles            generate list files in package
  -w, --keep-work           keep working directory
  -h, --help                show this help message
      --clean               remove downloaded sources and prebuilt packages
      --config=<config>     use custom config file
      --srcdir=<path>       override directory path for sources
      --pkgdir=<path>       override directory path for compiled package
      --workdir=<path>      override directory path for working dir
      --no-preinstall       skip preinstall script before install package
      --no-postinstall      skip postinstall script after install package
      --no-preupgrade       skip preupgrade script before upgrade package
      --no-postupgrade      skip postupgrade script after upgrade package
      --no-backup           skip backup configuration file when upgrading package
      --redownload          re-download source file
      
EOF
}

extract_opts() {
	while [ "$1" ]; do
		case $1 in
			--*) opts="$opts $1";;
			-*) char=${#1}; count=1
			    while [ "$count" != "$char" ]; do
					count=$((count+1))
					opts="$opts -$(echo $1 | cut -c $count)"
				done;;
			*) opts="$opts $1"
		esac
		shift
	done
	echo $opts
}

main() {	
	parse_opts $(extract_opts "$@")
	
	if [ -f "$PKGBUILD_CONF" ]; then
		. "$PKGBUILD_CONF"
	else
		msgerr "Config file not found ('$PKGBUILD_CONF')"
		exit 1
	fi
	
	[ "$CUSTOM_SOURCE_DIR" ]  && SOURCE_DIR="$CUSTOM_SOURCE_DIR"	
	[ "$CUSTOM_PACKAGE_DIR" ] && PACKAGE_DIR="$CUSTOM_PACKAGE_DIR"	
	[ "$CUSTOM_WORK_DIR" ]    && WORK_DIR="$CUSTOM_WORK_DIR"
	
	checkdir "$SOURCE_DIR" "$PACKAGE_DIR" "$WORK_DIR"
	
	# show usage
	[ "$SHOWHELP" ] && {
		help
		exit 0
	}
	
	if [ -f "$PKGBUILD_BSCRIPT" ]; then
		description=$(grep "^# description[[:blank:]]*:" $PKGBUILD_BSCRIPT | sed 's/^# description[[:blank:]]*:[[:blank:]]*//')
		. ./$PKGBUILD_BSCRIPT	
	else
		msgerr "'$PKGBUILD_BSCRIPT' file not found."
		exit 1
	fi
	
	check_buildscript
	set_options

	case $COMPRESSION_MODE in
		gz|bz2|xz) PKGNAME="$name-$version-$release.spkg.tar.$COMPRESSION_MODE" ;;
		        *) msgerr "Invalid compression mode. ($COMPRESSION_MODE)"; exit 1 ;;
	esac
	
	# generate .pkgfiles
	[ "$GENPKGFILES" ] && {
		generate_pkgfiles
		exit 0
	}
	
	# download source only
	[ "$DOWNLOAD_ONLY" ] && {
		download_src
		exit 0
	}
	
	# extract source only
	[ "$EXTRACT_ONLY" ] && {
		download_src
		prepare_src
		exit 0
	}
	
	# update md5sum
	[ "$UPDATE_MDSUM" ] && {
		download_src
		updatemdsum
		exit 0
	}
	
	# remove source and package
	[ "$CLEANUP" ] && {
		cleanup
		exit 0
	}

	LOCK_FILE="/tmp/pkgbuild.$name.lock"
	
	# check for lock file
	[ -f "$LOCK_FILE" ] && {
		msgerr "Cant build same package simultaneously."
		msgerr "remove '$LOCK_FILE' if no build process for '$name'."
		exit 1
	}
	
	# create lock file
	touch "$LOCK_FILE" 2>/dev/null || {
		msgerr "Cant create lock file in '$LOCK_FILE'."
		exit 1
	}
	
	# build package
	if [ -f "$PACKAGE_DIR/$PKGNAME" ] && [ ! "$FORCE_REBUILD" ]; then
		if [ ! "$INSTALL_PKG" ] && [ ! "$REINSTALL_PKG" ] && [ ! "$UPGRADE_PKG" ]; then
			echo "Package '$PKGNAME' is up-to-date."
			abort 0
		fi
	else
		msg "Building '$name-$version-$release'..."
		download_src
		prepare_src
		run_build
		packaging
		clearworkdir
	fi
	
	# install package
	if [ "$INSTALL_PKG" ] || [ "$REINSTALL_PKG" ] || [ "$UPGRADE_PKG" ]; then
		pkgadd $PACKAGE_DIR/$PKGNAME $INST_OPT $OPTS || abort 1
	fi
	
	abort 0	
}

trap "interrupted" 1 2 3 15

export LC_ALL=C

PKGBUILD_CONF="/etc/scratchpkg.conf"
PKGBUILD_BSCRIPT="spkgbuild"

SOURCE_DIR="/var/cache/scratchpkg/sources"
PACKAGE_DIR="/var/cache/scratchpkg/packages"
WORK_DIR="/var/cache/scratchpkg/work"
DOWNLOAD_PROG="auto"
COMPRESSION_MODE="xz"

OPTIONS="!libtool emptydirs strip zipman buildflags makeflags checksum !docs !locales"

INCLUDEINPKG="install readme mkdirs"

main "$@"