prereqs-installer

#!/bin/bash
#
# Install the packages and dependencies required for Mewdeko to run on Linux.
#
########################################################################################
#### [ Functions ]


########
# Install the packages and dependencies required by Mewdeko, on all compatible
# Linux distributions.
#
# Arguments:
# 	$1 - required
#       Distribution name.
# 	$2 - required
#       Distribution version.
#   $3 - required
#       OpenJDK version.
#   $4 - optional
#       True if .NET preferences must be set.
########
install_prereqs() {
    echo "Installing .NET Core..."
    ## Microsoft package signing key.
    curl -O https://packages.microsoft.com/config/"$1"/"$2"/packages-microsoft-prod.deb
    sudo dpkg -i packages-microsoft-prod.deb
    sudo rm -f packages-microsoft-prod.deb

    ## Ensure that .NET SDK is correctly installed on specific versions of Linux.
    if [[ $4 = true ]]; then
        if (hash dotnet &>/dev/null && [[ ! $(dotnet --version) ]]) &>/dev/null; then
            echo "${_YELLOW}While the .NET runtime is installed, the .NET SDK is not${_NC}"
            echo "Uninstalling existing .NET Core installation..."
            sudo apt remove -y dotnet-sdk-6.0
            sudo apt autoremove -y
        fi

        if [[ ! -f /etc/apt/preferences.d/custom-dotnet.pref ]]; then
            echo "Upating prefered .NET Core install method..."
            echo -e "Explanation: https://github.com/dotnet/core/issues/7699" \
                "\nPackage: *" \
                "\nPin: origin \"packages.microsoft.com\"" \
                "\nPin-Priority: 1001" | sudo tee /etc/apt/preferences.d/custom-dotnet.pref \
                || _STDERR "Failed to create '/etc/apt/preferences.d/custom-dotnet.pref'" "1"
            echo "Reinstalling .NET Core..."
        fi
    fi

    ## Install the SDK.
    sudo apt update && sudo apt install -y dotnet-sdk-6.0

    ## Install Java.
    echo "Installing '$3'..."
    sudo apt install -y "$3"

    ## Other prerequisites.
    echo "Installing other prerequisites..."
    sudo apt install -y redis-server git ccze apt-transport-https
}

########
# Inform the end-user that their system is not supported by the automatic installation
# of the prerequisites.
#
# Arguments:
#   None
########
unsupported() {
    echo "${_RED}The installer does not support the automatic installation and setup" \
        "of Mewdeko's prerequisites for your OS: $_DISTRO $_VER ${_ARCH}${_NC}"
    read -rp "Press [Enter] to return to the installer menu"
    exit 3
}


#### End of [ Functions ]
########################################################################################
#### [ Main ]


read -rp "We will now install Mewdeko's prerequisites. Press [Enter] to continue."

if [[ $_DISTRO = "ubuntu" ]]; then
    case "$_VER" in
        22.04)       install_prereqs "ubuntu" "$_VER" "openjdk-17-jdk" "true" ;;
        20.04|18.04) install_prereqs "ubuntu" "$_VER" "openjdk-17-jdk" ;;
        *)           unsupported ;;
    esac
elif [[ $_DISTRO = "debian" ]]; then
    case "$_SVER" in
        11) install_prereqs "debian" "$_SVER" "openjdk-17-jdk" ;;
        10) install_prereqs "debian" "$_SVER" "openjdk-11-jdk" ;;
        *)  unsupported ;;
    esac
elif [[ $_DISTRO = "linuxmint" ]]; then
    case "$_SVER" in
        21) install_prereqs "ubuntu" "22.04" "openjdk-17-jdk" "true" ;;
        20) install_prereqs "ubuntu" "20.04" "openjdk-17-jdk" ;;
        *)  unsupported ;;
    esac
fi

echo -e "\n${_GREEN}Finished installing prerequisites${_NC}"
read -rp "Press [Enter] to return to the installer menu"


#### End of [ Main ]
########################################################################################