#!/bin/bash

# Source makepkg.conf; fail if it is not found
if [[ -r '/etc/makepkg.conf' ]]; then
	source '/etc/makepkg.conf'
else
	echo '/etc/makepkg.conf not found!'
	exit 1
fi

# Source user-specific makepkg.conf overrides
if [[ -r ~/.makepkg.conf ]]; then
	source ~/.makepkg.conf
fi

strip_url() {
	echo "$1" | sed 's|^.*://.*/||g'
}

if [[ ! -f PKGBUILD ]]; then
	echo 'This must be run in the directory of a built package.'
	exit 1
fi

. PKGBUILD
if [[ $arch == 'any' ]]; then
	CARCH='any'
fi

STARTDIR=$(pwd)
TEMPDIR=$(mktemp -d /tmp/checkpkg-script.XXXX)
cd "$TEMPDIR"

for _pkgname in "${pkgname[@]}"; do
	if [[ -z ${epoch} ]] ; then
		pkgfile=${_pkgname}-${pkgver}-${pkgrel}-${CARCH}${PKGEXT}
	else
		pkgfile=${_pkgname}-${epoch}:${pkgver}-${pkgrel}-${CARCH}${PKGEXT}
	fi

	if [[ -f "$STARTDIR/$pkgfile" ]]; then
		ln -s "$STARTDIR/$pkgfile" "$pkgfile"
	elif [[ -f "$PKGDEST/$pkgfile" ]]; then
		ln -s "$PKGDEST/$pkgfile" "$pkgfile"
	else
		echo "File \"$pkgfile\" doesn't exist"
		exit 1
	fi

	tmp=$(pacman -Spdd --noconfirm "$_pkgname")

	if [[ $? -ne 0 ]]; then
		echo "Couldn't download previous package for $_pkgname."
		exit 1
	fi

	pkgurl=$(echo $tmp | rev | cut -d ' ' -f 1 | rev)

	oldpkg=$(strip_url "$pkgurl")

	if [[ "$(basename $oldpkg)" = "$(basename $pkgfile)" ]]; then
		echo "The built package ($_pkgname) is the one in the repo right now!"
		exit 1
	fi

	if [[ ! -f $oldpkg ]]; then
		if echo $pkgurl | grep '^file:///' > /dev/null 2>&1; then
			ln -s "${pkgurl#file://}" $(basename "${pkgurl#file://}")
		elif [[ -f "$PKGDEST/$oldpkg" ]]; then
			ln -s "$PKGDEST/$oldpkg" "$oldpkg"
		elif [[ -f "$STARTDIR/$oldpkg" ]]; then
			ln -s "$STARTDIR/$oldpkg" "$oldpkg"
		else
			wget --quiet "$pkgurl"
		fi
	fi

	bsdtar tf "$oldpkg" > "filelist-$_pkgname-old"
	bsdtar tf "$pkgfile" > "filelist-$_pkgname"

	sort -o "filelist-$_pkgname" "filelist-$_pkgname"
	sort -o "filelist-$_pkgname-old" "filelist-$_pkgname-old"

	sdiff -s "filelist-$_pkgname-old" "filelist-$_pkgname"

	if diff "filelist-$_pkgname-old" "filelist-$_pkgname" | grep '\.so' > /dev/null 2>&1; then
		mkdir -p pkg
		cd pkg
		bsdtar xf ../"$pkgfile" > /dev/null
		for i in $(diff "../filelist-$_pkgname-old" "../filelist-$_pkgname" | grep \> | grep '\.so' | awk '{print $2}'); do
			echo "${i}: " "$(objdump -p "$i" | grep SONAME)"
		done
		cd ..
	else
		echo "No soname differences for $_pkgname."
	fi
done

echo "Files saved to $TEMPDIR"