#!/bin/bash
set +e
strip_yaml_comments() {
    local file=$1

    if [[ ! -f "$file" ]]; then
        echo "File not found: $file"
        return 1
    fi

    # Filter out lines that are either full-line comments or completely empty
    sed -i '/^\s*#/d;/^\s*$/d' "$file"

    if [ $? -eq 0 ]; then
        echo "Comments stripped successfully in $file"
    else
        echo "Failed to strip comments from the file."
        return 1
    fi
}

download_and_process_config() {
    local url="https://raw.githubusercontent.com/juanfont/headscale/main/config-example.yaml"
    local target_dir="/etc/headscale"
    local target_file="${target_dir}/config-example.yaml"

    # Create target directory if it does not exist
    mkdir -p "$target_dir"

    # Download the file using curl
    curl -o "$target_file" "$url"

    if [ $? -eq 0 ]; then
        echo "Config downloaded successfully to $target_file"
        # Process the downloaded file to strip comments
        strip_yaml_comments "$target_file"
    else
        echo "Failed to download the config file"
        return 1
    fi
}


insert_env_placeholders() {
    local config_file="/etc/headscale/config-example.yaml"

    if [[ ! -f "$config_file" ]]; then
        echo "Config file $config_file not found."
        return 1
    fi

    # Substitute only simple, single-line configuration options
    sed -i 's|^server_url:.*|server_url: ${SERVER_URL}|' "$config_file"
    sed -i 's|^listen_addr:.*|listen_addr: ${LISTEN_ADDR}|' "$config_file"
    sed -i 's|^metrics_listen_addr:.*|metrics_listen_addr: ${METRICS_LISTEN_ADDR}|' "$config_file"
    sed -i 's|^grpc_listen_addr:.*|grpc_listen_addr: ${GRPC_LISTEN_ADDR}|' "$config_file"
    sed -i 's|^grpc_allow_insecure:.*|grpc_allow_insecure: ${GRPC_ALLOW_INSECURE}|' "$config_file"
    sed -i 's|^db_type:.*|db_type: ${DB_TYPE}|' "$config_file"
    sed -i 's|^db_path:.*|db_path: ${DB_PATH}|' "$config_file"
    sed -i 's|^acme_url:.*|acme_url: ${ACME_URL}|' "$config_file"
    sed -i 's|^acme_email:.*|acme_email: ${ACME_EMAIL}|' "$config_file"
    sed -i 's|^tls_letsencrypt_hostname:.*|tls_letsencrypt_hostname: ${TLS_LETSENCRYPT_HOSTNAME}|' "$config_file"
    sed -i 's|^tls_letsencrypt_cache_dir:.*|tls_letsencrypt_cache_dir: ${TLS_LETSENCRYPT_CACHE_DIR}|' "$config_file"
    sed -i 's|^unix_socket:.*|unix_socket: ${UNIX_SOCKET}|' "$config_file"
    sed -i 's|^unix_socket_permission:.*|unix_socket_permission: ${UNIX_SOCKET_PERMISSION}|' "$config_file"

    echo "Environment variable placeholders inserted in $config_file"
}


download_and_process_config

insert_env_placeholders