#!/bin/bash

DISK='/dev/sda'

# System configuration variables
TIMEZONE='America/Sao_Paulo'
LOCALE='en_US.UTF-8 UTF-8\npt_BR.UTF-8 UTF-8'
USERNAME=$2
PASSWORD=$3
HOSTNAME=$4
BOOT_SIZE=256

is_efi() {
  [ -d '/sys/firmware/efi/efivars' ]
}

user_configurations() {
  echo "Choose your user name"
  read USERNAME
  echo "Set your root password"
  read -s PASSWORD
  echo "Please, confirm the root password"
  read -s PASSWORD_CONFIRMATION
  while [ $PASSWORD != $PASSWORD_CONFIRMATION ]
  do
    echo "Error: The password does not match!"
    echo "Please: try again:"
    read -s PASSWORD
    echo "Please, confirm the root password:"
    read -s PASSWORD_CONFIRMATION
  done
  echo "Set your hostname:"
  read HOSTNAME
  echo "Listing disks"
  parted -l
  echo "Choose your device to format: (Default device $DISK)"
  read CHOSEN_DEVICE
  if [ -z $CHOSEN_DEVICE ]
  then
    echo "We will use the default then"
  else
    $DISK = "/dev/$CHOSEN_DEVICE"
  fi
}

config_partitions() {
  local memory=$(vmstat -s -S M | grep 'total memory' | tr -dc '0-9')
  local memory_addr=$(($memory + $BOOT_SIZE))M

  echo "Formatting disk"

  if is_efi
  then
    parted -s "$DISK" \
      mklabel gpt \
      mkpart primary fat32 1 "$BOOT_SIZE"M \
      mkpart primary ext4 $memory_addr 100% \
      mkpart primary linux-swap "$BOOT_SIZE"M  $memory_addr \
      set 1 esp on \
      set 2 LVM on \
      set 3 LVM on
  else
    parted -s "$DISK" \
      mklabel msdos \
      mkpart primary ext2 1 "$BOOT_SIZE"M \
      mkpart primary ext4 $memory_addr 100% \
      mkpart primary linux-swap "$BOOT_SIZE"M  $memory_addr \
      set 1 bios_grub on \
      set 2 LVM on \
      set 3 LVM on
  fi
}

format_disk() {
  local boot_dev="$DISK"1
  local lvm_dev="$DISK"2
  local swap_dev="$DISK"3

  config_partitions

  is_efi && mkfs.fat -F32 "$boot_dev" || mkfs.ext2 -L boot "$boot_dev"
  mkfs.ext4 -L root "$lvm_dev"
  mkswap $swap_dev
  swapon $swap_dev

  mount $lvm_dev /mnt
  mkdir /mnt/boot
  mount $boot_dev /mnt/boot
}

install_base() {
  pacstrap /mnt base base-devel linux linux-firmware
}

config_locale() {
  printf $LOCALE >> /etc/locale.gen
  locale-gen
  cat > /etc/locale.conf <<EOF
LANG=en_US.UTF-8
EOF
}

set_hostname() {
  cat > /etc/hosts <<EOF
127.0.0.1 localhost
::1  localhost
127.0.1.1 $HOSTNAME.localdomain	$HOSTNAME
EOF
hostnamectl set-hostname $HOSTNAME
}

create_user() {
  echo "Creating user"
  groupadd sudo
  useradd -m -s /bin/zsh -G root,sudo "$USERNAME"
  echo -en "$PASSWORD\n$PASSWORD" | passwd "$USERNAME"
  echo "%sudo ALL=(ALL) ALL" >> /etc/sudoers
  echo "# Config your zshrc file" >> /home/"$USERNAME"/.zshrc
}

install_tools() {
  local tools='zsh wget htop wpa_supplicant'
  yes | pacman -S $tools
}

config_system() {
  echo "Start system configurations"
  mv /etc/localtime /etc/localtime_original
  ln -sT "/usr/share/zoneinfo/$TIMEZONE" /etc/localtime
  hwclock --systohc
  config_locale
  set_hostname
  echo -en "$PASSWORD\n$PASSWORD" | passwd
  create_user
  install_tools
}

install_grub() {
  yes | pacman -S grub
  if is_efi
  then
    yes | pacman -S efibootmgr
    grub-install --target=x86_64-efi --efi-directory=/boot --bootloader-id=arch
    mkdir /boot/EFI/boot
    cp /boot/EFI/arch/grubx64.efi /boot/EFI/boot/bootx64.efi
  else
    grub-install --target=i386-pc $DISK
  fi
  grub-mkconfig -o /boot/grub/grub.cfg
}

install_i3() {
  echo "Installing i3 and dependencies"
  cd "/home/$USERNAME"
  sudo -u $USERNAME wget "https://raw.githubusercontent.com/Julianobsg/arch-config/master/i3_install.sh"
  chmod +x i3_install.sh
  echo $PASSWORD | sudo -Su $USERNAME ./i3_install.sh
}

finish_installation() {
  install_grub
  rm /install.sh
  exit
  umount /mnt/boot
  umount /mnt
  echo "Config finished, please boot your system."
}

install_arch() {
  if [ -z "$USERNAME" ]
  then
    user_configurations
  fi

  if [ "$1" == "config" ]
  then
    config_system
    install_i3
    finish_installation
  else
    format_disk
    install_base
    genfstab -U /mnt >> /mnt/etc/fstab
    cp $0 /mnt/install.sh
    arch-chroot /mnt ./install.sh config $USERNAME $PASSWORD $HOSTNAME
  fi
}

install_arch $1 $2 $3 $4