#!/bin/bash
# archinst - v1.3.9
# Copyight (c) 2024 Joseph Chris <joseph@josephcz.xyz> under MIT License
#
# Simple Arch Linux installation script
#

version="1.3.9"
echo "========================================================="
echo "    archinst.sh version $version by Joseph Chris"
echo "========================================================="
echo "                    BEFORE INSTALL"
echo "    1. Connect to Internet"
echo "    2. Complete the partition and mount to /mnt"
echo "      a. UEFI+GPT: Ensure ESP partition mounted to /efi"
echo "      b. BIOS+GPT: Require 2MB partition type 'bios boot'"
echo "      b. UEFI+MBR: NOT SUPPORTTED/POSSIBLE BY THIS SCRIPT"
echo "       SEE: https://wiki.archlinux.org/title/Partitioning"
echo "    3. LUKS is not supported."
echo "    4. If you are not ready, press Ctrl+C to exit!"
echo "========================================================="
echo -e "\n\n"

install_default="base linux linux-firmware vim openssh lvm2 mdadm btrfs-progs dosfstools exfatprogs jfsutils xfsprogs"
echo "Will install: $install_default"
read -p "Enter other packages? " install
install="$install_default $install"

echo "Ok, we will install: $install"
read -p "What timezone are you using? [UTC] " timezone
if [ ! -f "/mnt/usr/share/zoneinfo/$timezone" ]; then
	echo "I can not find the timezone. Set to UTC."
	timezone=UTC
fi
echo "Locale: we will set en_US.UTF-8 as default. You can change it later after system installation."

read -p "What is your hostname? [archlinux] " sethostname
if [ -z $sethostname ]; then
	sethostname=archlinux
fi

github=""
read -p "Do you want to import SSH key from GitHub? [GitHub Username/leave it blank] " github
if [ ! -z $github ]; then
	echo "Added install openssh."
	install="$install openssh"
fi

if [ ! -d /sys/firmware/efi/efivars ]; then
	bootmode=bios
else
	bootmode=uefi
fi

# Will always set root password
set_root_password=Yes
# read -p "Do you want to set root password later? [y/n] " set_root_password
# if [ $set_root_password = "y" ]; then
# 	set_root_password=Yes
# else
# 	set_root_password=No
# fi

mbresp="(none)"
read -p "Install GRUB? [y/n] " grub
if [ $grub = "y" ]; then
	grub=Yes
	if [ $bootmode = "bios" ]; then
		read -p "Which disk to install MBR? [/dev/sda] " mbresp
		if [ -z $mbresp ]; then
			mbresp=/dev/sda
		fi
		echo "Install MBR to $mbresp"
	else
		read -p "Which dir to install GRUB EFI? [/efi] " mbresp
		if [ -z $mbresp ]; then
                        mbresp=/efi
                fi
                echo "Install GRUB EFI to $mbresp"
	fi
else
	grub=No
fi

# confirm
pkgarray=($install)
echo "========================================================="
echo "                 Installation Summary                    "
echo "========================================================="
echo "  Timezone:          $timezone"
echo "  Locale:            en_US.UTF-8"
echo "  Hostname:          $sethostname"
echo "  Boot Type:         $bootmode"
echo "  Set Password:      $set_root_password"
echo "  GitHub SSH Key:    $github"
echo "  Install GRUB:      $grub"
echo "  MBR/ESP:           $mbresp"
echo "  Packages:          [See Below]"
for pkg in "${pkgarray[@]}"; do
echo "                     $pkg                                "
done
echo "========================================================="
read -p "Is that right? [y/n] " confirm
if [ $confirm != "y" ]; then
	echo "Abort"
	exit 2
fi

# start installation
echo "Setting up time..."
timedatectl set-ntp true
timedatectl status
echo "Updating keyring..."
echo "pacman -Sy archlinux-keyring"
yes | pacman -Sy archlinux-keyring
echo "Installing base system..."
echo "pacstrap /mnt base linux linux-firmware $install"
pacstrap /mnt base linux linux-firmware $install
echo "Generating fstab..."
genfstab -U /mnt >> /mnt/etc/fstab
echo "Setting up timezone..."
arch-chroot /mnt ln -sf /usr/share/zoneinfo/$timezone /etc/localtime
arch-chroot /mnt hwclock --systohc
echo "Setting up locale..."
cp /mnt/etc/locale.gen /mnt/etc/locale.gen.available
echo "en_US.UTF-8 UTF-8" > /mnt/etc/locale.gen
echo "LANG=en_US.UTF-8"  > /mnt/etc/locale.conf
arch-chroot /mnt locale-gen
echo "Setting up hostname..."
echo "$sethostname" >  /mnt/etc/hostname
echo "127.0.0.1	localhost"         >> /mnt/etc/hosts
echo "::1		localhost" >> /mnt/etc/hosts
echo "127.0.0.1	$sethostname"      >> /mnt/etc/hosts
if [ ! -z $github ]; then
	echo "Installing SSH Keys of GitHub user $github..."
	mkdir -p /mnt/root/.ssh
	curl https://github.com/$github.keys -o /mnt/root/.ssh/authorized_keys
	chmod 600 /mnt/root/.ssh/authorized_keys
	arch-chroot /mnt systemctl enable sshd
	echo "SSH Key:"
	cat /mnt/root/.ssh/authorized_keys
fi

for netif_class in /sys/class/net/*; do
    netif_name=$(basename $netif_class)
    netif_addr=$(cat /sys/class/net/$netif_name/address)
    if [ $netif_name != "lo" ]; then
        echo "Setting up network interface $netif_name..."
        cat > /mnt/etc/systemd/network/$netif_name.network <<EOF
[Match]
MACAddress=$netif_addr

[Network]
DHCP=true
EOF
    fi
done
arch-chroot /mnt systemctl enable systemd-networkd
echo "nameserver 1.1.1.1" >> /mnt/etc/resolv.conf
arch-chroot /mnt ln -sf /usr/bin/vim /usr/bin/vi

echo "Updating initramfs..."
# https://wiki.archlinux.org/title/Installation_guide_(%E7%AE%80%E4%BD%93%E4%B8%AD%E6%96%87)
# https://wiki.archlinux.org/title/Mkinitcpio_(%E7%AE%80%E4%BD%93%E4%B8%AD%E6%96%87)
# https://wiki.archlinux.org/title/Install_Arch_Linux_on_LVM#Configure_the_system
# https://wiki.archlinux.org/title/Dm-crypt/Encrypting_an_entire_system
# https://wiki.archlinux.org/title/RAID_(%E7%AE%80%E4%BD%93%E4%B8%AD%E6%96%87)
initramfs_hooks="base udev autodetect keyboard keymap consolefont modconf block filesystems mdadm_udev encrypt lvm2 keyboard fsck"
initramfs_modules="dm-raid dm_integrity raid0 raid1 raid10 raid456"
sed -i "s/^HOOKS=(.*)/HOOKS=($initramfs_hooks)/g"       /mnt/etc/mkinitcpio.conf
sed -i "s/^MODULES=(.*)/MODULES=($initramfs_modules)/g" /mnt/etc/mkinitcpio.conf
while read -r dm_tabline;do
	dm_dev_name=$(echo "$dm_tabline" | cut -d":" -f1)
	dm_dev_uuid=$(echo "$dm_tabline" | cut -d" " -f6 | cut -d":" -f5)
	echo -e "$dm_dev_name\t$dm_dev_uuid" >> /mnt/etc/crypttab
done <<< $(dmsetup table --target crypt)
arch-chroot /mnt mkinitcpio -P

if [ $set_root_password = "Yes" ]; then
	echo "Please set root password."
	arch-chroot /mnt passwd
fi

if [ $grub != "No" ]; then
	echo "Installing GRUB... You have 5 seconds to press Ctrl-C to abrot."
	sleep 5
	if [ $bootmode = "uefi" ]; then
		arch-chroot /mnt pacman -Syy grub efibootmgr
		echo "Install GURB x86_64-efi to $mbresp..."
		arch-chroot /mnt grub-install --target=x86_64-efi --efi-directory=$mbresp --bootloader-id=GRUB
	else
		arch-chroot /mnt pacman -Syy grub
		echo "Install GRUB i386-pc to $mbresp..."
		arch-chroot /mnt grub-install --target=i386-pc $mbresp
	fi
	sed -i "s/^GRUB_CMDLINE_LINUX_DEFAULT=.*/GRUB_CMDLINE_LINUX_DEFAULT=\"\"/g" /mnt/etc/default/grub
	echo "Generating GRUB configuration..."
	arch-chroot /mnt grub-mkconfig -o /boot/grub/grub.cfg
fi

# print notes
echo "Done! Welcome to be an Archman!"
echo "Content of fstab:"
cat /mnt/etc/fstab
cat << EOF
=========================================================
                     INSTALL COMPLETE
=========================================================
PLEASE DO STEPS BELOW
THESE STEPS WILL NOT DONE AUTOMATICALLY:

1. CHECK /mnt/etc/fstab BEFORE REBOOT!
2. Update microcodes IN CHROOT:
       pacman -Syy amd-ucode
       pacman -Syy intel-ucode
=========================================================
EOF