"""test utils for tests of examples

A module to test must have:

- main(): a method
- EXPOUT: string which contains expected output
- EXPERR: string which contains expected error output
"""

__all__ = ['TestUtil']

import io
import logging
import os
import sys

import cssutils


class OutReplacement:
    "io.StringIO does not work somehow?!"

    def __init__(self):
        self.t = ''

    def write(self, t):
        if t.startswith('b') and t.endswith("'"):
            t = t[2:-1]

        self.t += t

    def getvalue(self):
        self.t = self.t.replace('\\n', '\n').replace('\\\\', '\\')
        return self.t


class TestUtil:
    def __init__(self):
        "init out and err to catch both"
        self._out = OutReplacement()  # StringIO()
        sys.stdout = self._out

        self._err = io.StringIO()
        hdlr = logging.StreamHandler(self._err)
        cssutils.log._log.addHandler(hdlr)

    def end(self, expo, expe):
        "return out, err"
        sys.stdout = sys.__stdout__

        out = self._out.getvalue()
        err = self._err.getvalue()

        ok = out == expo and err == expe
        if not ok:
            print()
            if out != expo:
                print(f'### out:\n{out!r}\n### != expout:\n{expo!r}\n')
            else:
                print(f'### err:\n{err!r}\n### != experr:\n{expe!r}\n')
        return ok


modules = 0
errors = 0


def mod(module):
    global modules, errors
    modules += 1
    t = TestUtil()
    module.main()
    ok = t.end(module.EXPOUT, module.EXPERR)
    if not ok:
        errors += 1
    print('---', ok, ':', os.path.basename(module.__file__))
    print()


def main():
    global modules, errors

    import build

    mod(build)
    import customlog

    mod(customlog)
    import imports

    mod(imports)
    import parse

    mod(parse)
    import selectors_tolower

    mod(selectors_tolower)

    import cssencodings

    mod(cssencodings)

    import minify

    mod(minify)

    print()
    print(80 * '-')
    print('Ran %i tests (%i errors).' % (modules, errors))
    print('doctests do not work in Python 3 (yet?)!')


if __name__ == '__main__':
    main()