manjaro2archcachy/attempt_2.sh

RED="\e[31m"
GREEN="\e[32m"

DEFAULT_MIRRORLIST="/etc/pacman.d/mirrorlist"
DEFAULT_KERNEL="linux-cachyos"
PROPAGATE_MANJARO="Keep all currently installed Manjaro kernels"

# yes, they're hard-coded. For now at least.
KNOWN_KERNELS=(
    "$PROPAGATE_MANJARO",
    "linux",
    "linux-lts",
    "linux-hardened",
    "linux-rt",
    "linux-cachyos",
    "linux-cachyos-lts",
    "linux-cachyos-hardened",
    "linux-cachyos-bore",
    "linux-cachyos-eevdf",
    "linux-cachyos-bmq",
    "linux-cachyos-deckify",
    "linux-cachyos-rc",
    "linux-cachyos-rt-bore",
    "linux-cachyos-server",
    "linux-zen"
    #"linux-cachyos-cacule",
    #"linux-cachyos-debug",
    #"linux-cachyos-gcc",
)

assert() {
    if ! $1; then
        echo "Script depends on $2 to function, please resolve manually."
    fi

    # Yes, this is always true, but anyway.
    return $1
}

is_installed() {
    return ! which "$1" > /dev/null
}

run_unprivileged() {
    sudo -u "$USERNAME" "$@"
}

log() {
    if "$1"; then
        echo -e "$2...${GREEN}yes $3"
    else
        echo -e "$2...${RED}no"
    fi
}

# Credit to NaN on StackOverflow for this solution.
# https://stackoverflow.com/questions/29436275/how-to-prompt-for-yes-or-no-in-bash
prompt_bool() {
    if $2; then
        options="[Y/n]"
        default="y"
    else
        options="[y/N]"
        default="n"
    fi

    echo -n "$1 $options"
    read -r tmp
    tmp=${tmp:-${default}}

    if [[ "$tmp" =~ ^[yY]$ ]]; then
        return true
    else
        return false
    fi
}

# CHECKS
if ! $?; then
    echo "Script must be run with elevated permissions."
    exit 1
fi

refresh_checks() {
    [ $(id -u) = 0 ]
    ROOT_PERMS=$?
    log $ROOT_PERMS "root_perms"

    LSPCI=$(is_installed lspci)
    log $LSPCI "lspci"

    PACMAN=$(is_installed pacman)
    log $PACMAN "pacman"

    MHWD_KERNEL=$(is_installed mhwd-kernel)
    log $MHWD_KERNEL "mhwd-kernel"

    SUDO=$(is_installed sudo)
    log $SUDO "sudo"

    CURL=$(is_installed curl)
    log $CURL "curl"

    REFLECTOR=$(is_installed reflector)
    log $REFLECTOR "reflector"

    YAY=$(is_installed yay)
    log $YAY "yay"

    USERNAME=$(logname)
    log $? "unprivileged_user" $USERNAME

    # Identify installed Manjaro kernels
    re="linux\d+"
    mhwd_dump=$(mhwd-kernel -li | grep "linux")

    ACTIVE_KERNEL=$(echo "$mhwd_dump" | grep "running" | grep -Po "$re" )
    [ ${#ACTIVE_KERNEL} > 0 ]
    log $? "active_kernel" $ACTIVE_KERNEL

    ALTERNATE_KERNELS=$(echo "$mhwd_dump" | grep -Po "$re" | grep -v "$ACTIVE_KERNEL")
    [ ${#ALTERNATE_KERNELS} > 0 ]
    log $? "alternate_kernels"
}

refresh_checks

assert $ROOT_PERMS "elevated permissions"
assert $LSPCI "lspci"
assert $PACMAN "pacman"
assert $MHWD_KERNEL "mhwd-kernel"
assert $SUDO "sudo"

# Attempt to recover from failing checks
deps=()

if ! $YAY; then
    deps+=("yay")
fi

if ! $CURL; then
    deps+=("curl")
fi

if [[ ${#deps} > 0 ]]; then
    pacman -Syy "${deps[@]}"
fi

if ! $REFLECTOR; then
    run_unprivileged yay -Syy "${deps[@]}"
fi

refresh_checks

assert $CURL "curl"
assert $REFLECTOR "reflector"

# OPTIONAL OPERATIONS
prompt_bool "Remove all kernels (excepting active)?" true
if $?; then
    # Remove alternate kernels
    # mhwd?
fi

# REPOS
# Install CachyOS Repos
# See: https://wiki.cachyos.org/features/optimized_repos/#adding-our-repositories-to-an-existing-arch-linux-install
cd $(mktemp -d)
curl https://mirror.cachyos.org/cachyos-repo.tar.xz -o cachyos-repo.tar.xz
tar xvf cachyos-repo.tar.xz
cd cachyos-repo

# Just in case, ensure the script can be executed.
if [[ ! -x "cachyos-repo.sh" ]]; then
    chmod +x cachyos-repo.sh
fi

./cachyos-repo.sh

# Backup Manjaro Repos
mv "$DEFAULT_MIRRORLIST" "$DEFAULT_MIRRORLIST.bak"

# Install Arch Repos
curl -o "$DEFAULT_MIRRORLIST" "https://archlinux.org/mirrorlist/all/"
reflector\
    --fastest "32"\
    --protocol "https"\
    --sort "rate"\
    --country "CA,NZ,DE,NL,PL,SE"\
    --save "$DEFAULT_MIRRORLIST"
pacman -Syy

if ! is_installed chwd; then
    pacman -S chwd
    assert $(is_installed chwd) "chwd"
fi

# INSTALL NEW KERNEL(S)

# List available kernels
for idx in "${!KNOWN_KERNELS[@]}"; do
    printf "%s\t%s\n" "$idx" "${KNOWN_KERNELS[$idx]}"
done

echo -n "Kernel(s): "
read -r tmp

if [[ ${#tmp} > 0 ]]; then
    # Credit to bgoldst on StackOverflow for this solution.
    # https://stackoverflow.com/questions/10586153/how-to-split-a-string-into-an-array-in-bash
    kernels=$(readarray -td, a <<< "$tmp,"; unset 'a[-1]'; declare -p a)
else
    kernels="$DEFAULT_KERNEL"
fi

# TODO: Install kernels

# Handle propagations
#   DKMS propagations
#   Nvidia drivers migration from DKMS to -nvidia-open
#       Arch and Zen kernels?
chwd --autoconfigure

# Kill Orphans
#   DKMS && !PROPAGATE_DKMS, but maybe CHWD will remove the need for this???
#   MHWD
#   Pamac