#!/usr/bin/env bash
#
# Copyright (c) 2024 YunoHost Contributors
#
# This file is part of YunoHost (see https://yunohost.org)
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#

n_install_dir="/opt/node_n"
node_version_path="$n_install_dir/n/versions/node"

# Load the version of node for an app, and set variables.
#
# usage: ynh_use_nodejs
#
# `ynh_use_nodejs` has to be used in any app scripts before using node for the first time.
# This helper will provide alias and variables to use in your scripts.
#
# To use npm or node, use the alias `ynh_npm` and `ynh_node`.
#
# Those alias will use the correct version installed for the app.
# For example: use `ynh_npm install` instead of `npm install`
#
# With `sudo` or `ynh_exec_as`, use instead the fallback variables `$ynh_npm` and `$ynh_node`
# And propagate $PATH to sudo with $ynh_node_load_PATH
# Exemple: `ynh_exec_as $app $ynh_node_load_PATH $ynh_npm install`
#
# $PATH contains the path of the requested version of node.
# However, $PATH is duplicated into $node_PATH to outlast any manipulation of `$PATH`
# You can use the variable `$ynh_node_load_PATH` to quickly load your node version
# in $PATH for an usage into a separate script.
# Exemple: $ynh_node_load_PATH $final_path/script_that_use_npm.sh`
#
#
# Finally, to start a nodejs service with the correct version, 2 solutions
#  Either the app is dependent of node or npm, but does not called it directly.
#  In such situation, you need to load PATH :
# ```
# Environment="__NODE_ENV_PATH__"
# ExecStart=__FINALPATH__/my_app
# ```
# You will replace __NODE_ENV_PATH__ with $ynh_node_load_PATH.
#
#  Or node start the app directly, then you don't need to load the PATH variable
# ```
# ExecStart=__YNH_NODE__ my_app run
# ```
# You will replace __YNH_NODE__ with $ynh_node
#
#
# 2 other variables are also available
#   - $nodejs_path: The absolute path to node binaries for the chosen version.
#   - $nodejs_version: Just the version number of node for this app. Stored as 'nodejs_version' in settings.yml.
#
# Requires YunoHost version 2.7.12 or higher.
ynh_use_nodejs() {
    nodejs_version=$(ynh_app_setting_get --app=$app --key=nodejs_version)

    # Get the absolute path of this version of node
    nodejs_path="$node_version_path/$nodejs_version/bin"

    # Allow alias to be used into bash script
    shopt -s expand_aliases

    # Create an alias for the specific version of node and a variable as fallback
    ynh_node="$nodejs_path/node"
    alias ynh_node="$ynh_node"
    # And npm
    ynh_npm="$nodejs_path/npm"
    alias ynh_npm="$ynh_npm"

    # Load the path of this version of node in $PATH
    if [[ :$PATH: != *":$nodejs_path"* ]]; then
        PATH="$nodejs_path:$PATH"
    fi
    node_PATH="$PATH"
    # Create an alias to easily load the PATH
    ynh_node_load_PATH="PATH=$node_PATH"
    # Same var but in lower case to be compatible with ynh_replace_vars...
    ynh_node_load_path="PATH=$node_PATH"
    # Prevent yet another Node and Corepack madness, with Corepack wanting the user to confirm download of Yarn
    export COREPACK_ENABLE_DOWNLOAD_PROMPT=0
}

# Install a specific version of nodejs
#
# ynh_install_nodejs will install the version of node provided as argument by using n.
#
# usage: ynh_install_nodejs --nodejs_version=nodejs_version
# | arg: -n, --nodejs_version=      - Version of node to install. When possible, your should prefer to use major version number (e.g. 8 instead of 8.10.0).
#
# `n` (Node version management) uses the `PATH` variable to store the path of the version of node it is going to use.
# That's how it changes the version
#
# Refer to `ynh_use_nodejs` for more information about available commands and variables
#
# Requires YunoHost version 2.7.12 or higher.
ynh_install_nodejs() {
    # Use n, https://github.com/tj/n to manage the nodejs versions

    # Declare an array to define the options of this helper.
    local legacy_args=n
    local -A args_array=([n]=nodejs_version=)
    local nodejs_version
    # Manage arguments with getopts
    ynh_handle_getopts_args "$@"

    # Create $n_install_dir
    mkdir --parents "$n_install_dir"

    # Install the requested version of nodejs
    if [[ $YNH_ARCH == "arm64" ]]; then
        N_PREFIX=$n_install_dir "$YNH_HELPERS_DIR/vendor/n/n" $nodejs_version --arch=arm64
    else
        N_PREFIX=$n_install_dir "$YNH_HELPERS_DIR/vendor/n/n" $nodejs_version
    fi

    # Find the last "real" version for this major version of node.
    final_nodejs_version=$(find "$n_install_dir/n/versions/node/$nodejs_version"* -maxdepth 0 | sort --version-sort | tail --lines=1)
    final_nodejs_version=$(basename "$final_nodejs_version")

    # Store nodejs_version into the config of this app
    nodejs_version="$final_nodejs_version"
    ynh_app_setting_set --key=nodejs_version --value="$final_nodejs_version"

    ynh_use_nodejs
}

# Remove the version of node used by the app.
#
# usage: ynh_remove_nodejs
#
# This helper will check if another app uses the same version of node.
# - If not, this version of node will be removed.
# - If no other app uses node, n will be also removed.
#
# Requires YunoHost version 2.7.12 or higher.
ynh_remove_nodejs() {
    nodejs_version=$(ynh_app_setting_get --app=$app --key=nodejs_version)

    ynh_app_setting_delete --app=$app --key=nodejs_version

    # Garbage-collect unused versions
    local installed_versions="$(N_PREFIX=/opt/node_n "$YNH_HELPERS_DIR/vendor/n/n" ls | awk -F/ '{print $2}')"
    for version in $installed_versions; do
        if ! grep -qr "^nodejs_version: '$nodejs_version'" /etc/yunohost/apps/*/settings.yml; then
            N_PREFIX=$n_install_dir "$YNH_HELPERS_DIR/vendor/n/n" rm $nodejs_version
        fi
    done

    # If no other app uses n, remove n
    if ! grep -qr "^nodejs_version:" /etc/yunohost/apps/*/settings.yml; then
        ynh_safe_rm "$n_install_dir"
        sed --in-place "/N_PREFIX/d" /root/.bashrc
    fi
}