#!/bin/bash
set -e

# Author            : Eshan Roy <eshan@snigdhaos.or>
# Author URL        : https://eshanized.github.io/

echo
echo "--->> Start snigdhaos-fixes <<---"
echo

# Function to get a kernel parameter value, with a default if the parameter is not found
get_kernel_param() {
    local param=$1
    local default=$2
    local value

    # Extract the kernel parameter value, or use default if not found
    value=$(cat /proc/cmdline | tr ' ' '\n' | grep "^${param}=" | cut -d '=' -f 2-)
    echo "${value:-${default}}"
}

# Function to get the driver selection from the kernel parameters
get_driver() {
    get_kernel_param driver
}

# Function to wait for pacman to become available if locked
wait_for_pacman() {
    local timeout=30
    local interval=5

    # Wait for pacman to finish operations if the database lock file exists
    while [ -e "/var/lib/pacman/db.lck" ]; do
        echo "Pacman is not ready yet. Trying in ${interval} seconds..."
        sleep ${interval}
        ((timeout -= interval))
        if ((timeout <= 0)); then
            echo "[WARNING] Pacman is still locked after waiting ${timeout}s. Attempting to remove db.lck..."
            rm /var/lib/pacman/db.lck || { echo "[ERROR] Failed to remove db.lck. Exiting."; exit 1; }
        fi
    done
}

# Get the kernel parameter 'driver' to determine which selection to use
selection=$(get_driver)

echo
echo "Your Selection: ${selection}"
echo

# Handle different driver selection cases
case ${selection} in
    free)
        echo "Removing NVIDIA DKMS and related packages..."
        wait_for_pacman
        pacman -Rns --noconfirm nvidia-dkms nvidia-utils nvidia-settings egl-wayland || { echo "[ERROR] Failed to remove NVIDIA packages."; exit 1; }
        cp /etc/calamares/settings-advanced-no-nvidia.conf /etc/calamares/settings-advanced.conf || { echo "[ERROR] Failed to copy Calamares settings."; exit 1; }
        echo "NVIDIA packages removed, and settings updated."
        ;;
    freenonouveau)
        echo "Removing NVIDIA DKMS, NVIDIA utilities, and Nouveau..."
        wait_for_pacman
        pacman -Rns --noconfirm nvidia-dkms nvidia-utils nvidia-settings egl-wayland xf86-video-nouveau || { echo "[ERROR] Failed to remove NVIDIA and Nouveau packages."; exit 1; }
        cp /etc/calamares/settings-advanced-no-nvidia.conf /etc/calamares/settings-advanced.conf || { echo "[ERROR] Failed to copy Calamares settings."; exit 1; }
        echo "NVIDIA and Nouveau packages removed, and settings updated."
        ;;
    nonfree)
        echo "Keeping NVIDIA and Nouveau packages."
        ;;
    nonfreenonouveau)
        echo "Keeping NVIDIA DKMS; removing Nouveau."
        wait_for_pacman
        pacman -Rns --noconfirm xf86-video-nouveau || { echo "[ERROR] Failed to remove Nouveau package."; exit 1; }
        echo "Nouveau package removed."
        ;;
    *)
        echo "[ERROR] Invalid selection: ${selection}. Exiting."
        exit 1
        ;;
esac

echo
echo "--->> End snigdhaos-fixes <<---"
echo