#!/usr/bin/env sh

# This script installs the default things for having a stylish zsh
user_shell=`getent passwd $USER | cut -f7 -d:`

info() {
    echo -e '\033[1m'info:'\033[0m' $@
}

info_n() {
    echo -en '\033[1m'info:'\033[0m' $@
}

warn() {
    echo -e '\033[33;1m'warning:'\033[0m' $@
}

warn_n() {
    echo -en '\033[33;1m'warning:'\033[0m' $@
}

error() {
    echo -e '\033[31;1m'error:'\033[0m' $@
}

error_n() {
    echo -en '\033[31;1m'error:'\033[0m' $@
}

echo_green() {
    echo -e '\033[32;1m'$@'\033[0m'
}

test_command() {
    command -v $1 > /dev/null 2>&1
}

yes_no_ask_required() {
    yes_no_ask $@ "(required)"
    if [ $? -ne 0 ]; then
        error "refused to perform required task, can't continue"
        exit 1
    fi
}

yes_no_ask() {
    info_n $@ "[Y/n]"
    read answer
    if ! [[ "$answer" == "N" ]] && ! [[ "$answer" == "n" ]]; then
        return 0
    else
        return 1
    fi
}

install() {
    test_command apt
    if [ $? -eq 0 ]; then
        sudo apt install -yqq $1
        return
    fi

    test_command pacman
    if [ $? -eq 0 ]; then
        sudo pacman -S $1
        return
    fi

    error "distribution not recognized, can't install $1."
}

install_python3() {
    test_command apt
    if [ $? -eq 0 ]; then
        sudo apt install -yqq python3 python3-pip
        return
    fi

    test_command pacman
    if [ $? -eq 0 ]; then
        sudo pacman -S python python-pip
        return
    fi

    error "distribution not recognized, can't install python3."
}

install_python_neovim() {
    test_command pip3
    if [ $? -eq 0 ]; then
        sudo pip3 install neovim
        return
    fi

    test_command pip
    if [ $? -eq 0 ]; then
        sudo pip install neovim
        return
    fi

    error "couldn't find pip, can't install python-neovim."
}

install_neovim() {
    test_command apt
    if [ $? -eq 0 ]; then
        test_command add-apt-repository

        if [ $? -ne 0 ]; then
            sudo apt update -qq && sudo apt install -yqq software-properties-common
        fi

        sudo add-apt-repository -y ppa:neovim-ppa/stable
        sudo apt update -yqq
        sudo apt install -yqq neovim
        return
    fi

    test_command pacman
    if [ $? -eq 0 ]; then
        sudo pacman -S neovim
        return
    fi

    error "distribution not recognized, can't install neovim."
}

git_clone() {
    info_n "cloning $1..."
    git clone $1 $2 > /dev/null 2>&1
    if [ $? -eq 0 ]; then
        echo " OK!"
    else
        echo
        error "clone failed!"
    fi
}

clone_dotfiles() {
    if [ ! -d $HOME/.config/dotfiles ]; then

        test_command git
        if [ $? -ne 0 ]; then
            if [ $sudo_available -ne 0 ]; then
                error "git is needed, but you don't have git neither sudo"
                return 1
            else
                yes_no_ask_required "you'll need git for this, do you wish to install git ?"
                install git
            fi
        fi

        git_clone https://gitea.tforgione.fr/tforgione/dotfiles/ $HOME/.config/dotfiles
    fi
}

configure_dotfiles() {
    yes_no_ask "do you wish to configure the dotfiles ?"
    if [ $? -ne 0 ]; then
        return
    fi

    clone_dotfiles
}

configure_shell() {

    yes_no_ask "do you wish to install and configure zsh ?"
    if [ $? -ne 0 ]; then
        yes_no_ask "you don't want zsh ? Ok... but can I at least give you a nice bashrc ?"

        if [ $? -ne 0 ]; then
            info "ok :'( I guess I'm not doing anything then"
            return
        fi

        clone_dotfiles
        rm -f ~/.bashrc
        ln -s `realpath ~/.config/dotfiles/bashrc` `realpath ~/.bashrc`

        info "bashrc configured successfully"

        return
    fi

    clone_dotfiles

    test_command zsh
    if [ $? -ne 0 ]; then
        if [ $sudo_available -ne 0 ]; then
            error "zsh is needed, but you don't have zsh neither sudo"
            return 1
        else
            yes_no_ask_required "this magnificent prompt is based on zsh, do you wish to install zsh ?"
            install zsh
        fi
    fi

    mkdir -p $HOME/.config
    if [ ! -d $HOME/.config/oh-my-zsh ]; then
        git_clone https://github.com/robbyrussell/oh-my-zsh/ $HOME/.config/oh-my-zsh
    fi

    if [ -f $HOME/.zshrc ]; then
        path1=`realpath $HOME/.zshrc`
        path2=`realpath $HOME/.config/dotfiles/zshrc`
        if [ "$path1" == "$path2" ]; then
            info "it seems that your zshrc is already a good link."
        else
            if `realpath $HOME/.zshrc`; then
                warn "you already have a zshrc, it will be moved to ~/.zshrc.bak"
                mv $HOME/.zshrc $HOME/.zshrc.bak
            fi
            info "linking zshrc"
            ln -s $HOME/.config/dotfiles/zshrc $HOME/.zshrc
        fi
    else
        info "linking zshrc"
        ln -s $HOME/.config/dotfiles/zshrc $HOME/.zshrc
    fi

    if [ "$user_shell" == "/bin/zsh" ]; then
        info "it seems that you already use zsh."
    else
        info "it seems your shell is not zsh..."

        if [ $sudo_available -eq 0 ]; then
            # Sudo is available, run chsh
            yes_no_ask "do you want to change your shell ?"
            if [ $? -eq 0 ]; then
                info "changing your shell"
                sudo chsh $user -s /bin/zsh
            else
                info "not doing anything"
            fi
        else
            info "you don't have root, but you can run 'exec zsh' at the end of your bashrc"
            yes_no_ask "do you wish to do that ?"
            if [ $? -eq 0 ]; then
                echo >> $HOME/.bashrc
                echo "exec zsh" >> $HOME/.bashrc
                echo >> $HOME/.bashrc
            else
                info "not doing anything"
            fi
        fi
    fi
}

configure_neovim() {
    test_command nvim
    if [ $? -ne 0 ] && [ $sudo_available -ne 0 ]; then
        warn "you don't have neither sudo nor neovim, skipping neovim configuration"
        return
    fi

    yes_no_ask "do you wish to install and configure neovim ?"

    if [ $? -ne 0 ]; then
        info "not installing neovim"
        return
    fi

    clone_dotfiles

    test_command nvim
    if [ $? -ne 0 ]; then
        info "installing neovim"
        install_neovim
    fi

    # Try and install python3 and python-neovim
    test_command python3
    if [ $? -ne 0 ]; then
        install_python3
    fi

    install_python_neovim

    # Create config files an directories
    mkdir -p $HOME/.config/nvim $HOME/.nvim/backups $HOME/.nvim/swp $HOME/.nvim/undo
    rm -f $HOME/.config/nvim/init.vim
    ln -s $HOME/.config/dotfiles/init.vim $HOME/.config/nvim/init.vim

    # Install vim plug
    curl -fLo ~/.local/share/nvim/site/autoload/plug.vim --create-dirs \
        https://raw.githubusercontent.com/junegunn/vim-plug/master/plug.vim

    # Install plugins
    nvim +PlugInstall +qa
}

main() {
    echo_green "=== WELCOME TO TFORGIONE'S CONFIG INSTALLER ==="

    info "before anything, i need to know if your user can use sudo"
    yes_no_ask "can your user use sudo ?"
    sudo_available=$?

    configure_dotfiles
    configure_shell
    configure_neovim
}

main < /dev/tty