#!/usr/bin/python3
""""
Entrypoint of a Woodpecker CI docker image plugin that permit to publish Debian
packages on a Aptly repository using its API
"""

import datetime
import os
import re
import sys

from requests import Session
from requests.adapters import HTTPAdapter
from urllib3.util import Retry

from debian_parser import PackagesParser


def from_env(name, default=None):
    """ Retrieve a parameter from environment """
    for var in (f'PLUGIN_{name}', f'APTLY_{name}'):
        if var in os.environ:
            return os.environ[var]
    return default


# Handle parameters from environment
API_URL = from_env('API_URL', None)
if not API_URL:
    print('API URL not provided')
    sys.exit(1)

API_USERNAME = from_env('API_USERNAME', None)
if not API_USERNAME:
    print('API username not provided')
    sys.exit(1)

API_PASSWORD = from_env('API_PASSWORD', None)
if not API_PASSWORD:
    print('API password not provided')
    sys.exit(1)

MAX_RETRY = from_env('MAX_RETRIES', None)

REPO_NAME = from_env('REPO_NAME', None)
PREFIX = from_env('PREFIX', '.')
REPO_COMPONENT = from_env('REPO_COMPONENT', 'main')
INPUT_PATH = from_env('PATH', 'dist')
SOURCE_NAME = from_env('SOURCE_PACKAGE_NAME', None)

# List changes files
changes_files_regex = (
    # pylint: disable=consider-using-f-string
    re.compile(r'^%s_.*\.changes$' % SOURCE_NAME)
    if SOURCE_NAME else
    re.compile(r'^.*\.changes$')
)
changes_files = []
try:
    for filename in os.listdir(INPUT_PATH):
        filepath = os.path.join(INPUT_PATH, filename)
        if not os.path.isfile(filepath):
            continue
        if changes_files_regex.match(filename):
            changes_files.append(filepath)
except FileNotFoundError:
    print(f'Specified directory path "{INPUT_PATH}" not found')
    sys.exit(1)
except NotADirectoryError:
    print(f'Specified path "{INPUT_PATH}" is not a directory')
    sys.exit(1)

if not changes_files:
    print(f'No changes file found in {INPUT_PATH}')
    sys.exit(1)


# Initialize Aptly API client
session = Session()
session.auth = (API_USERNAME, API_PASSWORD)
if MAX_RETRY:
    retries = Retry(
        total=int(MAX_RETRY),
        status_forcelist=list(range(500, 600))
    )
    session.mount(API_URL, HTTPAdapter(max_retries=retries))


def get_repo_name(dist):
    """ Compute and retreive repository name """
    if REPO_NAME:
        return REPO_NAME
    value = f'{dist}_{REPO_COMPONENT}'
    if PREFIX != ".":
        value = f'{PREFIX}_{value}'
    return value


def parse_changes_file(filepath):
    """ Parse changes file to detect distribution and included files """
    dirpath = os.path.dirname(filepath)
    with open(filepath, "r", encoding="utf-8") as file_desc:
        changes_file = file_desc.read()

    parser = PackagesParser(changes_file)
    package_name = None
    distribution = None
    files = []
    for infos in parser.parse():
        for info in infos:
            if info['tag'].lower() == 'files':
                for line in info['value'].split('  '):
                    if not line:
                        continue
                    files.append(os.path.join(dirpath, line.split()[-1]))
            if info['tag'].lower() == 'distribution':
                if distribution:
                    print(
                        'More than one distribution found in changes file'
                        f'{os.path.basename(filepath)}.')
                    sys.exit(1)
                distribution = info['value']
            if info['tag'].lower() == 'source':
                if package_name:
                    print(
                        'More than one source package name found in changes '
                        f'file {os.path.basename(filepath)}.')
                    sys.exit(1)
                package_name = info['value']

    if not package_name:
        print(
            'Fail to detect source package name from changes file '
            f'{os.path.basename(filepath)}.')
        sys.exit(1)

    if not distribution:
        print(
            'Fail to detect distribution from changes file '
            f'{os.path.basename(filepath)}.')
        sys.exit(1)

    if not files:
        print(
            'No included file found in changes file'
            f'{os.path.basename(filepath)}.')
        sys.exit(1)

    return (package_name, distribution, files)


def get_published_distribution_other_components_sources(distribution):
    """ Retreive current published distribution using Aptly API """
    url = f'{API_URL}/publish'
    result = session.get(url)
    if result.status_code != 200:
        print(
            'Fail to retreive current published distribution '
            f'{distribution} using Aptly API (HTTP code: {result.status_code})'
        )
        sys.exit(1)
    for data in result.json():
        if data['Prefix'] != PREFIX:
            continue
        if data['Distribution'] != distribution:
            continue
        if data['SourceKind'] != 'snapshot':
            print(
                f'The distribution {distribution} currently published on '
                f'prefix "{PREFIX}" do not sourcing packages from snapshot(s) '
                f'but from {data["SourceKind"]}.'
            )
            sys.exit(1)
        return [
            source for source in data['Sources']
            if source['Component'] != REPO_COMPONENT
        ]
    print(
        f'Distribution {distribution} seem not currently published on prefix '
        f'"{PREFIX}". Please manually publish it a first time before using '
        f'{os.path.basename(sys.argv[0])}.'
    )
    sys.exit(1)
    return False


def upload_file(package_name, filepath):
    """ Upload a file using Aptly API """
    url = f'{API_URL}/files/{package_name}'
    with open(filepath, 'rb') as file_desc:
        result = session.post(url, files={'file': file_desc})
    return (
        result.status_code == 200 and
        f'{package_name}/{os.path.basename(filepath)}' in result.json()
    )


def include_file(repo_name, package_name, changes_file):
    """ Include a changes file using Aptly API """
    url = (
        f'{API_URL}/repos/{repo_name}/include/{package_name}/'
        f'{os.path.basename(changes_file)}'
    )
    result = session.post(url)
    data = result.json()
    if data.get('FailedFiles'):
        print()
        print(f'Some error occurred including {changes_file}:')
        print('Failed files:')
        for failed_file in data['FailedFiles']:
            print(f'  - {os.path.basename(failed_file)}')
        if data.get('Report', {}).get('Warnings'):
            print('Warnings:')
            print('  - %s' % '\n  - '.join(data['Report']['Warnings']))
        print()
        return False
    if not (
        result.status_code == 200 and
        data.get('Report', {}).get('Added')
    ):
        print(
            f'Unknown error occurred including {changes_file}'
            'See APTLY API logs for details.')
        return False
    return True


for changes_file in changes_files:
    print(f'Handle changes file {changes_file}:')
    package_name, distribution, filepaths = parse_changes_file(changes_file)
    filepaths += [changes_file]
    repo_name = get_repo_name(distribution)

    other_components_sources = \
        get_published_distribution_other_components_sources(distribution)

    print(' - Upload files:')
    for filepath in filepaths:
        if not upload_file(package_name, filepath):
            print(
                f'    - {filepath}: fail to upload file. See APTLY API logs '
                'for details.')
            sys.exit(1)
        else:
            print(f'    - {filepath}')

    print(f' - Include changes file {changes_file}:')
    if include_file(repo_name, package_name, changes_file):
        print('    - Changes file included')
    else:
        sys.exit(1)

    # Create a snapshot of the repository
    snap_name = datetime.datetime.now().strftime(f'%Y%m%d-%H%M%S_{repo_name}')
    print(f'Create new snapshot "{snap_name}" of repository "{repo_name}"')

    url = f'{API_URL}/repos/{repo_name}/snapshots'
    payload = {'Name': snap_name}
    result = session.post(url, json=payload)
    try:
        data = result.json()
    except Exception:  # pylint: disable=broad-except
        data = {}
    error = (
        result.status_code < 200 or
        result.status_code > 299 or
        data.get('Name') != snap_name or
        not data.get('CreatedAt')
    )
    if error:
        print(
            f'Fail to create snapshot "{snap_name}" of repository '
            f'"{repo_name}". See APTLY API logs for details.')
        sys.exit(1)

    # Update published snapshot of the distribution
    print(
        f'Update published snapshot of distribution "{distribution}" to '
        f'"{snap_name}" (prefix: {PREFIX}, component: {REPO_COMPONENT})')
    if other_components_sources:
        print('Note: keep other currently published components:')
        for source in other_components_sources:
            print(f'- {source["Component"]}: {source["Name"]}')
    url = f'{API_URL}/publish/:{PREFIX}/{distribution}'
    payload = {
        'Snapshots': other_components_sources + [
            {
                'Component': REPO_COMPONENT,
                'Name': snap_name
            }
        ]
    }
    result = session.put(url, json=payload)
    if (
        result.status_code < 200 or
        result.status_code > 299
    ):
        print(
            'Fail to update published snapshot of distribution '
            f'"{distribution}" to "{snap_name}" (prefix: {PREFIX}, '
            f'component: {REPO_COMPONENT}). See APTLY API logs for details.')
        sys.exit(1)

print("Done.")