check_health.py

#!/usr/bin/env python3

import argparse
import os
import re
import sys

from PIL import Image

from _utils import get_attribut_names, get_attribute

HELP = """
For each given file, check the following conditions. Exit with exit-code 1, if at least one is not met.
"""


checks = []


def check(description):
    def inner(func):
        checks.append((description, func))

    return inner


def required_attribute(attr):
    @check(f"Attribute {attr} must be present")
    def has_attr(text, path):
        try:
            if not get_attribute(text, attr):
                yield f"attribute {attr} empty"
        except KeyError:
            yield f"attribute {attr} missing"


def _get_attr_path(text, path, attr):
    attr_path = get_attribute(text, attr)
    songdir = os.path.dirname(path)
    attr_path = os.path.join(songdir, attr_path)
    return attr_path


def file_exists(attr):
    @check(f"File referenced in {attr} must exist, if present")
    def file_exists(text, path):
        try:
            attr_path = _get_attr_path(text, path, attr)
        except KeyError:
            return

        if not os.path.isfile(attr_path):
            yield f"file referenced in attribute {attr} not found: {attr_path}"


def is_image_file(attr):
    @check(f"{attr} is an image file")
    def is_image_file(text, path):
        try:
            attr_path = _get_attr_path(text, path, attr)
        except KeyError:
            return

        try:
            Image.open(attr_path)
        except Exception as ex:
            if "cannot identify" in str(ex):
                yield f"file referenced in attribute {attr} is not an image"


required_attribute("MP3")
required_attribute("TITLE")
required_attribute("ARTIST")
required_attribute("LANGUAGE")

file_exists("MP3")
file_exists("COVER")
file_exists("VIDEO")
file_exists("BACKGROUND")

is_image_file("COVER")
is_image_file("BACKGROUND")


@check(f"Must have BACKGROUND or VIDEO")
def has_background_or_video(text, path):
    attrs = get_attribut_names(text)

    if "BACKGROUND" not in attrs and "VIDEO" not in attrs:
        yield f"has neither BACKGROUND nor VIDEO"


@check("All attribute names must be UPPERCASE")
def lower_case_attribute(text, path):
    for attr in get_attribut_names(text):
        if any(c.islower() for c in attr):
            yield f"attribute {attr} is lower case"


@check("There is an E line")
def lower_case_attribute(text, path):
    if not re.search("\nE\s*\n", text):
        yield "there is no E line"


def check_health(path, only_check):

    try:
        with open(path) as f:
            text = f.read()
    except UnicodeDecodeError:
        return ["not utf-8/ascii encoded."]

    problems = []

    for description, check in checks:
        if only_check and description not in only_check:
            continue
        problems.extend(check(text, path))

    return problems


def main(argv):
    found_problems = False

    description = HELP.strip() + "\n\n"
    description += " File is utf-8/ascii"
    description += "\n" + "\n".join(" " + c[0] for c in checks)

    parser = argparse.ArgumentParser(
        description=description, formatter_class=argparse.RawTextHelpFormatter
    )
    parser.add_argument(
        "--only-check",
        action="append",
        help="restrict checking to the given ones. encoding is always checked.",
    )
    parser.add_argument("files", nargs="+")

    args = parser.parse_args(argv)

    for path in args.files:
        problems = check_health(path, args.only_check)
        if problems:
            print(path)
            print("\n".join("  " + p for p in problems))
            found_problems = True

    return 0 if not found_problems else 1


if __name__ == "__main__":
    sys.exit(main(sys.argv[1:]))