#!/usr/bin/env bash

# This script serves as the NLTK build step of the
# [**Python Buildpack**](https://github.com/heroku/heroku-buildpack-python)
# compiler.
#
# A [buildpack](https://devcenter.heroku.com/articles/buildpacks) is an
# adapter between a Python application and Heroku's runtime.
#
# This script is invoked by [`bin/compile`](/).

# Syntax sugar.
source $BIN_DIR/utils

bpwatch start nltk_download

# Check that nltk was installed by pip, otherwise obviously not needed
python -m nltk.downloader -h >/dev/null 2>&1
if [ $? -eq 0 ]; then
    puts-step "Downloading NLTK corpora..."
    nltk_packages_definition="$BUILD_DIR/nltk.txt"
    if [ -f "$nltk_packages_definition" ]; then
        nltk_packages=$(tr "\n" " " < "$nltk_packages_definition")
        puts-step "Downloading NLTK packages: $nltk_packages"
        python -m nltk.downloader -d $BUILD_DIR/.heroku/python/nltk_data $nltk_packages  | indent
        set-env NLTK_DATA "/app/.heroku/python/nltk_data"
    else
        puts-warn "nltk.txt not found, not downloading any corpora"
    fi
fi


bpwatch stop nltk_download