#!/bin/bash

# matter-iso | MatterLinux ISO Build Script 
# Copyright (C) 2023 Matterlinux 

# 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/>.

############################
## logging functions/vars ##
############################
BOLD="\e[1m"
RESET="\e[0m"
GREEN="\e[32m"
BLUE="\e[34m"
GRAY="\e[37m"
RED="\e[31m"

success() {
  echo -e "$BOLD$GREEN>>>$RESET$BOLD $1$RESET"
}

info() {
  echo -e "$BOLD$BLUE>>>$RESET$BOLD $1$RESET"
}

error() {
  echo -e "$BOLD$RED>>>$RESET$BOLD $1$RESET"
  exit 1
}

####################
## util functions ##
####################
check_ret() {
  if [ $? -ne 0 ]; then
    error "$1"
  fi
}

setup_dns() {
  info "Setting up DNS"
  echo "nameserver 1.1.1.1" >> "$ROOTDIR/etc/resolv.conf"
}

clean_dns(){
  rm "$ROOTDIR/etc/resolv.conf"
}

#################
## main script ##
#################
if [ $# -ne 2 ]; then
  error "Please specify a release archive and an output directory"
fi
  
ARCHIVE="$(realpath $1)"
if [ ! -f $ARCHIVE ]; then 
  error "Archive file not found"
fi

PUBKEY="F9E70878C2FB389AEC2BA34CA3654DF5AD9F641D"
OUTDIR="$(realpath $2)"
ROOTDIR="$OUTDIR/root"
TMPDIR="$OUTDIR/tmp"

mkdir -p $TMPDIR
if [ -d $ROOTDIR ]; then
  rm -rf $ROOTDIR
fi
mkdir -p $ROOTDIR

pushd $OUTDIR > /dev/null
  cp $ARCHIVE release.tar.gz
  check_ret "Failed to copy the archive!"

  if [[ "$(file release.tar.gz)" != *"gzip compressed data"* ]]; then
    error "Bad archive format"
  fi

  info "Extracting archive..."
  tar xf release.tar.gz -C "$ROOTDIR"
  check_ret "Extract failed!"
popd > /dev/nul

setup_dns
  info "Adding public key"
  matter-chroot "$ROOTDIR" gpg --receive-key $PUBKEY 

  info "Installing extra packages"
  matter-chroot "$ROOTDIR" mp-sync 
  matter-chroot "$ROOTDIR" mp-install systemd dhcpcd 
  check_ret "Install failed!"
clean_dns

info "Configuring base system"
matter-chroot "$ROOTDIR" systemd-machine-id-setup 
matter-chroot "$ROOTDIR" systemctl preset-all 
matter-chroot "$ROOTDIR" cp /etc/skel/.* /root
matter-chroot "$ROOTDIR" cp /usr/sbin/init .

echo "matteriso" >> "$ROOTDIR/etc/hostname" 
cat > "$ROOTDIR/etc/issue" << EOF
Welcome to MatterLinux ISO!

- Login with root:root
- Sync before installing packages: mp-sync
- For installation: https://matterlinux.xyz/wiki/install
- Join XMPP for questions: general@conf.matterlinux.xyz 

Happy hacking!

EOF

info "Changing password"
cat > "$ROOTDIR/passwd.sh" << EOF
echo "root:root" | chpasswd 
EOF
matter-chroot "$ROOTDIR" bash /passwd.sh 
rm "$ROOTDIR/passwd.sh"

success "Setup completed, now creating the ISO"
pushd "$ROOTDIR" > /dev/null
  info "Building initrd..."
  find . | cpio --quiet -H newc -o | xz -T0 --check=crc32 > "$TMPDIR/initrd.img"
  check_ret "Failed to build initrd"
popd > /dev/null

setup_dns
  info "Installing and copying over the kernel"
  matter-chroot "$ROOTDIR" mp-install linux
  cp "$ROOTDIR/boot/vmlinuz-linux" "$TMPDIR"
clean_dns

info "Saving the grub configuration"
mkdir -p "$TMPDIR/boot/grub"
cat > "$TMPDIR/boot/grub/grub.cfg" << EOF
set default=0
set timeout=10
insmod efi_gop
insmod font
if loadfont /boot/grub/fonts/unicode.pf2
then
  insmod gfxterm
  set gfxmode-auto
  set gfxpayload=keep
  terminal_output gfxterm
fi

menuentry 'Matter GNU/Linux ISO' --class os {
  insmod gzio
  insmod part_msdos
  linux /vmlinuz-linux
  initrd /initrd.img
}
EOF

info "Building the ISO"
pushd "$OUTDIR" > /dev/null
  grub-mkrescue -o "matter.iso" $TMPDIR
  check_ret "grub-mkrescue failed!"
popd > /dev/null 

success "ISO is ready for boot"

info "Cleaning up"
rm -rf $TMPDIR
rm "$OUTDIR/release.tar.gz" 

success "Build completed"