prime-select

#!/bin/bash

function GetAlternative() {
    if [ "$(ls /var/lib/pacman/local/mesa-libgl* 2> /dev/null)" ]; then
        echo "intel"
    elif [ "$(ls /var/lib/pacman/local/nvidia-libgl* 2> /dev/null)" ]; then
        echo "nvidia"
    fi
}

# Install the desired LibGL
function SetAlternative() {
    desired=$1
    currentalternative=$(GetAlternative)
    if [ "$desired" = "$currentalternative" ]; then
        echo "LibGL already is $currentalternative, nothing to do"
    else
        if [ "$desired" = "nvidia" ]; then
            #pacman --noconfirm -Rdd mesa lib32-mesa xf86-video-intel
            pacman --noconfirm -S nvidia-utils lib32-nvidia-utils xf86-video-intel
        elif [ "$desired" = "intel" ]; then
            pacman --noconfirm -Rdd nvidia-utils lib32-nvidia-utils
            pacman --noconfirm -S mesa lib32-mesa
            pacman --noconfirm -S xf86-video-intel
        fi
    fi
}

# Write discrete card desired state in a file to be used later by another script
function WriteDesiredConfig() {
    discretestate=$1
    file="/etc/prime/state"
    if [ "$discretestate" = "nvidia" ]; then
        echo "ON" > "$file"
        cp /etc/prime/xorg.conf /etc/X11/
        if [ -f /etc/X11/xorg.conf.d/20-intel.conf ]; then
            rm /etc/X11/xorg.conf.d/20-intel.conf
        fi
        cp /etc/prime/Xsetup /usr/share/sddm/scripts/
        chmod +x /usr/share/sddm/scripts/Xsetup
        if ! lsmod | grep "bbswitch" &> /dev/null ; then
            modprobe bbswitch
        fi
        echo "ON" >> /proc/acpi/bbswitch
    elif [ "$discretestate" = "intel" ]; then
        echo "OFF" > "$file"
        cp /etc/prime/20-intel.conf /etc/X11/xorg.conf.d/
        if [ -f /etc/X11/xorg.conf ]; then
            rm /etc/X11/xorg.conf
        fi
        cp /etc/prime/Xsetup_intel /usr/share/sddm/scripts/Xsetup
        chmod +x /usr/share/sddm/scripts/Xsetup
    fi
}

argument=$1

# Checks if argument is valid and if not already active will attempt to do so.
if [ "$argument" = "intel" ] || [ "$argument" = "nvidia" ]; then
    if [[ $EUID -ne 0 ]]; then
        echo "This script must be run as root"
        exit 1
    fi
    SetAlternative "$argument"
    WriteDesiredConfig "$argument"
else
    if [ "$argument" = "query" ]; then
        currentalternative=$(GetAlternative)
        echo "$currentalternative"
    else
        echo "Usage prime.sh intel|nvidia|query"
    fi
fi