#!/bin/sh -e

pkginfodir='/var/log/packages/'
pkgscriptdir='/var/log/scripts/'

if [ "$#" -lt 1 ]; then
    echo "Usage: $0 <package32> [package64]" 1>&2
    exit 1
fi

pkg32="$(realpath "$1")"
unset pkg64
[ "$2" ] && pkg64="$(realpath "$2")"

# Extract all package info
# See /sbin/installpkg
pkgbase="$(echo "$pkg32" | sed -e 's?.*/??;s/\.t[bglx]z$//')"
pkgext="$(echo "$pkg32" | sed -e 's?.*/??;s/.*\.\(t[bglx]z\)$/\1/')"
pkgname="$(echo "$pkgbase" | sed -e 's?-[^-]*-[^-]*-[^-]*$??')"
pkgver="$(echo "$pkgbase" | sed -e 's?.*-\([^-]*\)-[^-]*-[^-]*$?\1?')"
pkgarch="$(echo "$pkgbase" | sed -e 's?.*-[^-]*-\([^-]*\)-[^-]*$?\1?')"
pkgbuild="$(echo "$pkgbase" | sed -e 's?.*-[^-]*-[^-]*-\([^-]*\)$?\1?')"

case "$pkgarch" in
    i?86) pkgarch=x86_64 ;;
    *)
        echo "Unsupported package architecture '$pkgarch'. Can't proceed." 1>&2
        exit 1
        ;;
esac

pkginfo="$pkginfodir/$pkgname-$pkgver-$pkgarch-$pkgbuild"
pkgscript="$pkgscriptdir/$pkgname-$pkgver-$pkgarch-$pkgbuild"

case "$pkgext" in
    tgz) tool=gzip ;;
    tbz) tool=bzip2 ;;
    tlz) tool=lzma ;;
    txz) tool=xz ;;
esac

temp="$(mktemp -d)"
trap "rm -rf '$temp'" EXIT

cd "$temp"
explodepkg "$pkg32"

# Remove all files present in the 64bit package
if [ "$pkg64" ]; then
    echo
    echo "Removing files:"
    $tool -cd "$pkg64" | tar-1.13 t | grep -v '^install/' | while read -r file; do
        echo "./$file"
        rm -f "./$file" 2> /dev/null || true
    done
else
    if [ ! -f "$pkginfo" ]; then
        echo "Package '$pkgname-$pkgver-$pkgarch-$pkgbuild' is not installed. Can't proceed." 1>&2
        exit 1
    fi

    # See /sbin/removepkg
    if fgrep './' "$pkginfo" 1> /dev/null 2>&1; then
        TRIGGER='^\.\/'
    else
        TRIGGER='FILE LIST:'
    fi

    echo
    echo 'Removing files:'
    sed -n "/$TRIGGER/,/^$/p" "$pkginfo" | fgrep -v 'FILE LIST:' | grep -v '^install/' | while read -r file; do
        echo "./$file"
        rm -f "./$file" 2> /dev/null || true
    done
fi

# Clean empty directories
echo
echo 'Empty directories:'
find . -type d -empty -print -delete

# Remove all symlinks present in the 64bit package
if [ -f install/doinst.sh ]; then
    if [ "$pkg64" ]; then
        if ! $tool -cd "$pkg64" | tar-1.13 xO install/doinst.sh > install/doinst.64; then
            echo "Failed to extract install/doinst.sh from '$pkg64'. Can't proceed." 1>&2
            exit 1
        fi
    else
        if [ ! -f "$pkgscript" ]; then
            echo "Package '$pkgname-$pkgver-$pkgarch-$pkgbuild' is installed but has no installation script. Can't proceed." 1>&2
            exit 1
        fi
        cp "$pkgscript" install/doinst.64
    fi

    # There's some packages that need special treatment
    if [ "$pkgname" = 'glib2' -o "$pkgname" = 'cups' -o "$pkgname" = 'sane' ]; then
        sed -i -e '/^for file in/,/^done/d' install/doinst.sh
    fi
    if [ "$pkgname" = 'cups' ]; then
        sed -i -e '/^if \[ -e etc\/rc.d\/rc.cups \]; then/,/^fi/d' install/doinst.sh
    fi
    if [ "$pkgname" = 'eudev' ]; then
        sed -i -e '/^if \[ \(-e etc\/rc.d\/rc.udev\|-r etc\/rc.d\/rc.udev.new\) \]; then/,/^fi/d' install/doinst.sh
    fi
    if [ "$pkgname" = 'dbus' ]; then
        sed -i -e '/^if \[ \(-e etc\/rc.d\/rc.messagebus\|-r etc\/rc.d\/rc.messagebus.new\) \]; then/,/^fi/d' install/doinst.sh
    fi

    # Extract all lines treating with symlinks or config files. See /sbin/removepkg
    sed -n -e 's,^[ ]*( [ ]*cd[ ]* .* [ ]*; [ ]*\(rm\|ln\) [ ]*-\(rf\|sf\)[ ]* .* [ ]*)[ ]*$,&,p' \
           -e 's,^[ ]*config .*[ ]*$,&,p' install/doinst.64 > install/doinst
    rm install/doinst.64

    echo
    echo 'Removed lines in doinst.sh:'
    if [ -s install/doinst ]; then
        fgrep -xf install/doinst install/doinst.sh || true

        # Remove all symlinks present in the 64bit package
        fgrep -vxf install/doinst install/doinst.sh > install/doinst.sh.new || true
        mv install/doinst.sh.new install/doinst.sh

        # If the resulting doinst.sh is empty, remove it.
        if [ ! -s install/doinst.sh ]; then
            rm install/doinst.sh
        fi
    fi
    rm install/doinst
fi

# Rename package in slack-desc
if [ -f install/slack-desc ]; then
    sed -i -e '/^\$\|#\| *|/!s/^[^:]*:/convert32-&/' install/slack-desc
fi

if ! find . | grep -v '^.$\|^./install' > /dev/null; then
    echo
    echo 'Package is empty. Not running makepkg.' 1>&2
    exit 0
fi

makepkg -l n -c n "$OLDPWD/convert32-$pkgname-$pkgver-$pkgarch-$pkgbuild.$pkgext"