#!/bin/bash

# Copyright (c) 2018 Jay Berkenbilt and Kurt Pfeifle
#
# This script is mainly meant to build an 'AppImage' from GitHub sources of QPDF via Travis CI on an
# Ubuntu Trusty (14.04) LTS system (see https://appimage.org/).
#
# But it also allows Linux users to build such an AppImage on their own systems. Please read
# 'README.md' from the top level Git sources to see what preconditions you must meet to build QPDF
# in general. The same apply to build an AppImage. Then follow these three steps:
#
#   1. Clone Git sources:  `git clone https://github.com/qpdf/qpdf.git git.qpdf`
#   2. Change into git dir:  `cd git.qpdf`
#   3. Run this script:  `bash appimage/build-appimage`
#
# The resulting AppImage will be placed in './appimage/build/QPDF-x86_64.AppImage'.
# Read the output of the script for hints in case something goes wrong.
#
# You may pass custom options for the configure step by setting them into the 'CUSTOM_CONFIGURE'
# environment variable and exporting it before running this script. For example:
#
#      export CUSTOM_CONFIGURE=" --enable-test-compare-images [--more-other-options]"
#
# ATTENTION:
#
#   1. To build the AppImage you should have a working internet connection.
#      Reason: the script downloads the most recent 'linuxdeployqt' utility for building the AppImage.
#   2. If you build the AppImage on a too recent Linux distribution, it may only work on the exact
#      distribution you build it on. For an AppImage to work on a wide range of different
#      distributions from the last 3-4 years if should be built on Ubuntu Trusty (14.04).


set -ex

# Support for signing the AppImage (only by original maintainer):
sign=
if [ "x$1" == "x--sign" ] ; then
    sign=--sign
fi


# Check if we are on Ubuntu Trusty
_osversion=$(cat /etc/os-release | grep PRETTY_NAME | awk -F'=' '{print $2}' | sed 's#"##g')

# Warn users building the AppImage locally:
if [ x"$_osversion" != x"Ubuntu 14.04.5 LTS" ] ; then
set +x
    echo ""
    echo "+==============================================================================================================+"
    echo "|| WARNING: You are about to build a QPDF AppImage on a system which is NOT Ubuntu 14.04.5 LTS ('Trusty').    ||"
    echo "||                                                                                                            ||"
    echo "||    Very likely you use a newer Linux distribution.                                                         ||"
    echo "||    The resulting AppImage will not be 'universally' usable.                                                ||"
    echo "||    Hence, it likely will not be capable of running on a large range of Linux distributions.                ||"
    echo "||    It will only reliably run on the very same systems it has been created on, and maybe some similar ones. ||"
    echo "+==============================================================================================================+"
    echo ""
set -x
fi


# From where do we run this script?
here="$(dirname $(readlink -f "$0"))"
top=$(dirname $here)

# Move to root of GitHub sources:
cd $top

# Set 'appdir' environment variable name:
appdir=$here/build/appdir

# Clean up stuff from previous build attempts:
rm -rf $here/build

# Prepare build of QPDF from sources:
./autogen.sh
./configure --prefix=/usr --enable-werror --enable-show-failed-test-output --enable-html-doc --enable-pdf-doc "$CUSTOM_CONFIGURE"

# Build!
make -j$(nproc)

# Run built-in QPDF checks:
make check

# Prepare AppDir which is the basis for the AppImage:
mkdir -p $appdir

# Install build result into AppDir:
make install DESTDIR=$appdir ; find $appdir

# Change into build directory:
cd $here/build

# Don't bundle developer stuff
rm -rf appdir/usr/include appdir/usr/lib/pkgconfig appdir/usr/lib/*.{a,la,so}

# Copy icon which is needed for desktop integration into place:
for i in appdir/usr/share/icons/hicolor/512x512/apps ; do
    mkdir -p $i
    cp $top/logo/qpdf.png $i
done

# Copy .desktop and .appdata.xml metadata for desktop integration into place:
for i in appdir/usr/share/applications ; do mkdir -p $i ; cp $top/appimage/qpdf.desktop     $i ; done
for i in appdir/usr/share/metainfo ;     do mkdir -p $i ; cp $top/appimage/qpdf.appdata.xml $i ; done
for i in appdir/usr/share/doc/qpdf ;     do mkdir -p $i ; cp $top/README* $i ; cp $top/NOTICE.md $i/README-notice.md ; cp $top/LICENSE.txt $i ; cp $top/Artistic-2.0 $i/Artistic-LICENSE.txt ; cp $top/ChangeLog $i/README-ChangeLog ; cp $top/TODO $i/README-todo ; done

# The following lines are experimental (for debugging; and to test support for unexpected future binaries added to QPDF):
for i in /usr/bin/env /bin/less /bin/busybox ; do cp $i appdir/usr/bin/ ; done
ls -l /usr/bin/env /bin/less /bin/busybox

# Fetch 'linuxdeployqt' which will transform the AppDir into an AppImage:
wget -c "https://github.com/probonopd/linuxdeployqt/releases/download/continuous/linuxdeployqt-continuous-x86_64.AppImage"
chmod a+x linuxdeployqt*.AppImage

# Set up a clean environment:
unset QTDIR ; unset QT_PLUGIN_PATH ; unset LD_LIBRARY_PATH

# Let 'linuxdeployqt' do its first stage of work:
./linuxdeployqt*.AppImage appdir/usr/share/applications/*.desktop -bundle-non-qt-libs

# In addition to the main executable, we have additional ones to process
./linuxdeployqt*.AppImage appdir/usr/bin/zlib-flate -bundle-non-qt-libs

# To eventually generate the AppImage we extract the linuxdeployqt AppImage to get access to the embedded 'appimagetool':
./linuxdeployqt*.AppImage --appimage-extract

# We want to run our custom AppRun script:
rm appdir/AppRun ; cp $top/appimage/AppRun appdir ; chmod a+x appdir/AppRun # Replace symlink with custom script

# If we are not on Ubuntu Trusty, we need to disable 'appstreamcli' validation:
if [ x"$_osversion" == x"Ubuntu 14.04.5 LTS" ] ; then
    appimagetool_param=""
else
    appimagetool_param="-n"
    set +x
    echo ""
    echo " Running 'appimagetool' with '-n' parameter..."
    echo " Reason: this does not seem to be a Travis CI build running on Ubuntu Trusty 14.04."
    echo " '-n' disables checking of AppStream data by the 'appstreamcli' utility since post-Trusty versions have incompatible changes."
    echo ""
    set -x
fi

# Set up a version string to include in the AppImage name
MAJOR_QPDF_VERSION=$( ./appdir/usr/bin/qpdf --version | grep "qpdf version" | awk '{print $3}' )
VERSION=${MAJOR_QPDF_VERSION}-continuous-${TRAVIS_JOB_NUMBER}-$(date "+%Y-%m-%d")-git.$(git rev-parse --short HEAD)-x86_64

# Remove the default AppRun/symlink and use our own custom AppRun script
rm appdir/AppRun ; cp $top/appimage/AppRun appdir; chmod a+x appdir/AppRun

set +x
# Finally, generate the AppImage:
PATH=./squashfs-root/usr/bin:$PATH ./squashfs-root/usr/bin/appimagetool $sign -g $appimagetool_param appdir qpdf-$VERSION.AppImage

# Tell everyone where our result is stored:
echo ""
echo "===================================================================================="
echo "  === AppImage is ready in $top/appimage/build ==="
echo "===================================================================================="
echo ""