#!/bin/bash

# This file is part of the LibreOffice project.
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

# Exit on errors
set -e

# Use of unset variable is an error
set -u

# If any part of a pipeline of commands fails, the whole pipeline fails
set -o pipefail

if [ `uname` != Darwin ]; then
    echo This is for macOS only >&2
    exit 1
fi

if [ $# != 3 ]; then
    echo Usage: $0 app-bundle-1 app-bundle-2 output-app-bundle
    exit 1
fi

if [ -d "$3" ]; then
    echo The directory $3 exists already
    exit 1
fi

if [ -f "$3" ]; then
    echo $3 exists and is a file
    exit 1
fi

if [ ! -d "$1" ]; then
    echo No such directory: $1
    exit 1
fi

if [ ! -d "$2" ]; then
    echo No such directory: $2
    exit 1
fi

ONE=$(cd "$1" && /bin/pwd)
TWO=$(cd "$2" && /bin/pwd)
mkdir "$3"
OUT=$(cd "$3" && /bin/pwd)

# Create all directories
(
    cd "$ONE"
    find . -type d -print
) |
(
    cd "$OUT"
    while read dirname; do
        mkdir -p "$dirname"
    done
)

# Check which files in 1 exist in 2, and if they are executable, merge them into a fat copy. For
# other files, just use one copy, assuming they are equivalent in most cases.
(
    cd "$ONE"
    find . -type l -or -type f
) |
(
    cd "$TWO"
    while read fname; do
        if test -L "$fname"; then
            ln -s $(readlink "$fname") "$OUT/$fname"
        elif test -f "$fname"; then
            case "$fname" in
                *.so | \
                *.dylib | \
                *.dylib.* | \
                */Frameworks/LibreOfficePython.framework/Versions/*/LibreOfficePython | \
                */Frameworks/LibreOfficePython.framework/Versions/*/Resources/Python.app/Contents/MacOS/LibreOfficePython | \
                */Library/Spotlight/OOoSpotlightImporter.mdimporter/Contents/MacOS/OOoSpotlightImporter)
                    lipo -create -output "$OUT/$fname" "$fname" "$ONE/$fname"
                    ;;
                # Ignore differences in these files. Let's hope it's just the timestamps.
                *.ot[tp] | \
                *.bau | \
                *.pyc | \
                */_sysconfigdata_m_darwin_darwin.py | \
                */Contents/Resources/firebird/security3.fdb | \
                */Contents/Resources/autocorr/acor_*.dat | \
                */Contents/Resources/resource/*/LC_MESSAGES/*.mo | \
                */Contents/Resources/config/images_*.zip)
                    cp "$fname" "$OUT/$fname"
                    ;;
                *)
                    case $(file --brief "$fname") in
                        Mach-O\ 64-bit\ executable\ *)
                            lipo -create -output "$OUT/$fname" "$fname" "$ONE/$fname"
                            ;;
                        *)
                            cmp -s "$fname" "$ONE/$fname" ||
                                echo "$fname differs and is not an executable!?" >&2
                            cp "$fname" "$OUT/$fname"
                    esac
            esac
        else
            # We ignore some files that can't be built for macOS on arm64 for now
            case "$fname" in
                ./Contents/Frameworks/LibreOfficePython.framework/Versions/3.7/lib/python*/lib-dynload/_ctypes.cpython-*m.so)
                    ;;
                *)
                    echo "$fname does not exist in $TWO" >&2
                    ;;
            esac
            cp "$ONE/$fname" "$OUT/$fname"
        fi
    done
)

# Look for files in 2 that don't exist in 1
(
    cd "$TWO"
    find . -type f -print
) |
(
    cd "$ONE"
    while read fname; do
        if test -f "$fname"; then
            :
        else
            echo "$fname does not exist in $ONE" >&2
            cp "$TWO/$fname" "$OUT/$fname"
        fi
    done
)

# Local Variables:
# tab-width: 4
# indent-tabs-mode: nil
# fill-column: 100
# End: