#!/bin/bash

# Creates a swap file in the btrfs subvolume, adds the swap file to /etc/fstab,
# adds a resume hook to mkinitcpio, and configures suspend-then-hibernate.

if [[ ! -f /sys/power/image_size ]]; then
  echo -e "\033[31mError: Hibernation is not supported on your system\033[0m" >&2
  exit 1
fi


MKINITCPIO_CONF="/etc/mkinitcpio.conf.d/omarchy_resume.conf"

# Check if hibernation is already configured
if [ -f "$MKINITCPIO_CONF" ] && grep -q "^HOOKS+=(resume)$" "$MKINITCPIO_CONF"; then
  echo "Hibernation is already set up"
  exit 0
fi

MEM_TOTAL_HUMAN=$(free --human | awk '/Mem/ {print $2}')
if ! gum confirm "Use $MEM_TOTAL_HUMAN on boot drive to make hibernation available?"; then
  exit 0
fi

SWAP_SUBVOLUME="/swap"
SWAP_FILE="$SWAP_SUBVOLUME/swapfile"

# Create btrfs subvolume for swap
if ! sudo btrfs subvolume show "$SWAP_SUBVOLUME" &>/dev/null; then
  echo "Creating Btrfs subvolume"
  sudo btrfs subvolume create "$SWAP_SUBVOLUME"
  sudo chattr +C "$SWAP_SUBVOLUME"
fi

# Create swapfile
if ! sudo swaplabel "$SWAP_FILE" &>/dev/null; then
  echo "Creating swapfile in Btrfs subvolume"
  MEM_TOTAL_KB="$(awk '/MemTotal/ {print $2}' /proc/meminfo)k"
  sudo btrfs filesystem mkswapfile -s "$MEM_TOTAL_KB" "$SWAP_FILE"
fi

# Add swapfile to fstab
if ! grep -Fq "$SWAP_FILE" /etc/fstab; then
  echo "Adding swapfile to /etc/fstab"
  sudo cp -a /etc/fstab "/etc/fstab.$(date +%Y%m%d%H%M%S).back"
  printf "\n# Btrfs swapfile for system hibernation\n%s none swap defaults,pri=0 0 0\n" "$SWAP_FILE" | sudo tee -a /etc/fstab >/dev/null
fi

# Enable swap
if ! swapon --show | grep -q "$SWAP_FILE"; then
  echo "Enabling swap on $SWAP_FILE"
  sudo swapon -p 0 "$SWAP_FILE"
fi

# Add resume hook to mkinitcpio
sudo mkdir -p /etc/mkinitcpio.conf.d
echo "Adding resume hook to $MKINITCPIO_CONF"
echo "HOOKS+=(resume)" | sudo tee "$MKINITCPIO_CONF" >/dev/null

# Configure suspend-then-hibernate
echo "Configuring suspend-then-hibernate"
sudo mkdir -p /etc/systemd/logind.conf.d /etc/systemd/sleep.conf.d
sudo cp "$OMARCHY_PATH/default/systemd/lid.conf" /etc/systemd/logind.conf.d/
sudo cp "$OMARCHY_PATH/default/systemd/hibernate.conf" /etc/systemd/sleep.conf.d/

# Regenerate initramfs
echo "Regenerating initramfs..."
sudo limine-mkinitcpio

echo

if gum confirm "Reboot to enable hiberation?"; then
  omarchy-cmd-reboot
fi