#!/usr/bin/env python3

"""
Used as a tool by the Makefile to generate sources from the assets.toml file.
"""

import toml
from mako.template import Template

def update_file(fname, contents):
    """
    Updates the given file with the given contents unless .fname.hash matches
    hash(contents).
    """
    try:
        with open(f'.{fname}.hash', 'r') as fhash:
            if fhash.read() == str(contents):
                return
    except:
        pass

    with open(fname, 'w') as f:
        f.write(contents)

def main(infile, outdir):
    """
    Entry point: generates outputs based on data in input files.
    """
    with open(infile, 'r') as f:
        data = toml.load(infile)

    for template_name in data:
        template = Template(filename=template_name)

        for output_name in data[template_name]:
            result = template.render(**data[template_name][output_name])
            update_file(outdir + '/' + output_name, result)