#!/usr/bin/env python
#
# This python file contains utility scripts to manage Python docs Polish translation.
# It has to be run inside the python-docs-pl git root directory.
#
# Inspired by django-docs-translations script by claudep.
#
# The following commands are available:
#
# * fetch: fetch translations from transifex.com and strip source lines from the
#          files.
# * recreate_tx_config: recreate configuration for all resources.
# * warn_about_files_to_delete: lists files that are not available upstream
# * generate_commit_msg: generates commit message with co-authors

from argparse import ArgumentParser
import os
from contextlib import chdir
from dataclasses import dataclass
from pathlib import Path
from subprocess import call, run, CalledProcessError
import sys
from tempfile import TemporaryDirectory
from typing import Self, Iterable
from warnings import warn

from polib import pofile, POFile
from transifex.api import transifex_api

LANGUAGE = 'pl'
PROJECT_SLUG = 'python-newest'
VERSION = '3.14'


def fetch():
    """
    Fetch translations from Transifex, remove source lines.
    """
    if (code := call('tx --version', shell=True)) != 0:
        sys.stderr.write('The Transifex client app is required.\n')
        exit(code)
    lang = LANGUAGE
    _call(f'tx pull -l {lang} --minimum-perc=1 --force --skip')
    for file in Path().rglob('*.po'):
        _call(f'msgcat --no-location -o {file} {file}')


def _call(command: str):
    if (return_code := call(command, shell=True)) != 0:
        exit(return_code)


def recreate_tx_config():
    """
    Regenerate Transifex client config for all resources.
    """
    with TemporaryDirectory() as directory:
        with chdir(directory):
            _clone_cpython_repo(VERSION)
            _build_gettext()
            with chdir(Path(directory) / 'cpython/Doc/build'):
                _create_txconfig()
                _update_txconfig_resources()
                with open('.tx/config', 'r') as file:
                    contents = file.read()
        contents = contents.replace('.//LC_MESSAGES/', '')
        with open('.tx/config', 'w') as file:
            file.write(contents)
    warn_about_files_to_delete()


def warn_about_files_to_delete():
    files = list(_get_files_to_delete())
    if not files:
        return
    warn(f'Found {len(files)} file(s) to delete: {", ".join(files)}.')


def _get_files_to_delete():
    with open('.tx/config') as config_file:
        config = config_file.read()
    for file in Path().rglob('*.po'):
        if os.fsdecode(file) not in config:
            yield os.fsdecode(file)


def _clone_cpython_repo(version: str):
    _call(
        f'git clone -b {version} --single-branch https://github.com/python/cpython.git --depth 1'
    )


def _build_gettext():
    _call('make -C cpython/Doc/ gettext')


def _create_txconfig():
    _call('sphinx-intl create-txconfig')


def _update_txconfig_resources():
    _call(
        f'sphinx-intl update-txconfig-resources --transifex-organization-name python-doc '
        f'--transifex-project-name={PROJECT_SLUG} --locale-dir . --pot-dir gettext'
    )


@dataclass
class ResourceLanguageStatistics:
    name: str
    total_words: int
    translated_words: int
    total_strings: int
    translated_strings: int

    @classmethod
    def from_api_entry(cls, data: transifex_api.ResourceLanguageStats) -> Self:
        return cls(
            name=data.id.removeprefix(f'o:python-doc:p:{PROJECT_SLUG}:r:').removesuffix(
                f':l:{LANGUAGE}'
            ),
            total_words=data.attributes['total_words'],
            translated_words=data.attributes['translated_words'],
            total_strings=data.attributes['total_strings'],
            translated_strings=data.attributes['translated_strings'],
        )


def _get_tx_token() -> str:
    if os.path.exists('.tx/api-key'):
        with open('.tx/api-key') as f:
            transifex_api_key = f.read()
    else:
        transifex_api_key = os.getenv('TX_TOKEN', '')
    return transifex_api_key


def _get_resources() -> list[transifex_api.Resource]:
    transifex_api.setup(auth=_get_tx_token())
    return transifex_api.Resource.filter(project=f'o:python-doc:p:{PROJECT_SLUG}').all()


def get_resource_language_stats() -> list[ResourceLanguageStatistics]:
    transifex_api.setup(auth=_get_tx_token())
    resources = transifex_api.ResourceLanguageStats.filter(
        project=f'o:python-doc:p:{PROJECT_SLUG}', language=f'l:{LANGUAGE}'
    ).all()
    return [ResourceLanguageStatistics.from_api_entry(entry) for entry in resources]


def progress_from_resources(
    resources: Iterable[ResourceLanguageStatistics],
) -> tuple[float, float]:
    word_pairs = ((e.translated_words, e.total_words) for e in resources)
    string_pairs = ((e.translated_strings, e.total_strings) for e in resources)
    translated_total_words, total_words = (sum(counts) for counts in zip(*word_pairs))
    translated_total_strs, total_strs = (sum(counts) for counts in zip(*string_pairs))
    return (
        translated_total_words / total_words * 100,
        translated_total_strs / total_strs * 100,
    )


def language_switcher(entry: ResourceLanguageStatistics) -> bool:
    language_switcher_resources_prefixes = ('bugs', 'tutorial', 'library--functions')
    return any(
        entry.name.startswith(prefix) for prefix in language_switcher_resources_prefixes
    )


def generate_commit_msg():
    """Generate a commit message
    Parses staged files and generates a commit message with Last-Translator's as
    co-authors.
    """
    translators: set[str] = set()

    result = run(
        ['git', 'diff', '--cached', '--name-only', '--diff-filter=ACM'],
        capture_output=True,
        text=True,
        check=True,
    )
    staged = [
        filename for filename in result.stdout.splitlines() if filename.endswith('.po')
    ]

    for file in staged:
        staged_file = run(
            ['git', 'show', f':{file}'], capture_output=True, text=True, check=True
        ).stdout
        try:
            old_file = run(
                ['git', 'show', f'HEAD:{file}'],
                capture_output=True,
                text=True,
                check=True,
            ).stdout
        except CalledProcessError:
            old_file = ''

        new_po = pofile(staged_file)
        old_po = pofile(old_file) if old_file else POFile()
        old_entries = {entry.msgid: entry.msgstr for entry in old_po}

        for entry in new_po:
            if entry.msgstr and (
                entry.msgid not in old_entries
                or old_entries[entry.msgid] != entry.msgstr
            ):
                translator = new_po.metadata.get('Last-Translator')
                translator = translator.split(',')[0].strip()
                if translator:
                    translators.add(f'Co-Authored-By: {translator}')
                break

    print('Update translation from Transifex\n\n' + '\n'.join(translators))


if __name__ == '__main__':
    RUNNABLE_SCRIPTS = (
        'fetch',
        'recreate_tx_config',
        'warn_about_files_to_delete',
        'generate_commit_msg',
    )

    parser = ArgumentParser()
    parser.add_argument('cmd', choices=RUNNABLE_SCRIPTS)
    options = parser.parse_args()

    eval(options.cmd)()