#!/usr/bin/env python3

# Copyright 2022-2023 Fairphone B.V.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#


"""Minimal Google Drive service account client.

Command line client for uploading files and folder to a Google Drive folder via
a Google service account. The client supports both regular personal drives ("My
Drive") as well as team drives. It is designed for scripting and automation,
thus working with a service account only. It is not intended to work as OAuth
client.

To use this client:
* Set up a Google Service account and give it access to required Drives.
* Create a service account key and download in JSON format.
* Point environment variable GOOGLE_APPLICATION_CREDENTIALS to this key file.

Refer to the Google Drive (Python) API reference for details:
* https://developers.google.com/resources/api-libraries/documentation/drive/v3/python/latest/index.html # noqa: E501 # pylint: disable=line-too-long
"""

import argparse
from io import FileIO
import json
import logging
import os
from pathlib import Path
import sys
from typing import Any, Dict, List, Optional, Union

import google.auth  # type: ignore
from googleapiclient.discovery import build, Resource  # type: ignore
from googleapiclient.errors import HttpError  # type: ignore
from googleapiclient.http import (  # type: ignore
    MediaUpload,
    MediaFileUpload,
    MediaIoBaseDownload,
)

import log

# See also https://developers.google.com/drive/api/guides/mime-types
MIMETYPE_GOOGLE_DRIVE_FOLDER = "application/vnd.google-apps.folder"

logger = logging.getLogger(__name__)


# https://stackoverflow.com/a/1094933
def sizeof_fmt(num: float, suffix: str = "B") -> str:
    """Pretty-print a file size."""
    for unit in ["", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei", "Zi"]:
        if abs(num) < 1024.0:
            return f"{num:3.1f}{unit}{suffix}"
        num /= 1024.0
    return f"{num:.1f}Yi{suffix}"


def list_drives(service: Resource) -> List[Dict[str, Any]]:
    """List accessible Google Drives.

    List both personal and team drives accessible with the current account.

    Returns:
        List of drives, each a dictionary of drive attributes.
    """
    drives = []
    page_token = None
    while True:
        response = (
            service.drives()
            .list(fields="nextPageToken,drives(id,name)", pageToken=page_token)
            .execute()
        )
        drives.extend(response.get("drives", []))
        page_token = response.get("nextPageToken", None)
        if not page_token:
            break

    return drives


def list_files(
    service: Resource,
    drive_id: Optional[str] = None,
    query: Optional[str] = None,
    max_entries: Optional[int] = None,
    order_by: str = "recency",
) -> List[Dict[str, str]]:
    """List files in a Google Drive folder.

    Arguments:
        service: Google Drive service resource object
        drive_id: Optional. ID of the Google drive to query. Default to the
            accounts own drive, "My Drive".
        query: Optional. A query for filtering the file results. See Drive API
            reference for details.
        max_entries: Optional. Restrict number of files returned.
        order_by: Choose ordering for returned results.

    Returns:
        List of files, for each list a mapping of fileId, name and mimeType.
    """
    files: List[Dict[str, Any]] = []
    page_token = None
    drive_params = {}
    page_size = 100
    if drive_id:
        drive_params = {
            "driveId": drive_id,
            # Below three MUST be set when using parameter 'driveId'
            "corpora": "drive",  # list files contained in driveId
            "includeItemsFromAllDrives": True,
            "supportsAllDrives": True,
        }
    while True:
        if max_entries and max_entries >= 0:
            remaining = max(0, max_entries - len(files))
            if remaining <= 0:
                break
            if remaining < page_size:
                page_size = remaining
        response = (
            service.files()
            .list(
                orderBy=order_by,
                pageSize=page_size,
                q=query,
                fields="nextPageToken,files(id,name,mimeType)",
                **drive_params,
                pageToken=page_token,
            )
            .execute()
        )
        files.extend(response.get("files", []))
        page_token = response.get("nextPageToken", None)
        if page_token is None:
            break
    return files


def list_files_strict(  # pylint: disable=too-many-arguments
    service: Resource,
    filename_match: Union[str, List[str]],
    drive_id: Optional[str] = None,
    query: Optional[str] = None,
    max_entries: Optional[int] = None,
    order_by: str = "recency",
) -> List[Dict[str, str]]:
    """List files, strictly filtered after fuzzy Google Drive search.

    Exactly one of filename or filename_contains must be set.

    Arguments:
        (All arguments of list_files())
        filename_match: Either of two: Full filename that result files must
            match; or list of filename components that must all be included in
            all result file name.

    Returns:
        Same results as list_files(), except for applying stricter filename
        matching.
    """
    files = list_files(
        service=service,
        drive_id=drive_id,
        query=query,
        max_entries=max_entries,
        order_by=order_by,
    )

    filtered_files = []
    if isinstance(filename_match, str):
        for file_entry in files:
            # Match full filenames
            if filename_match == file_entry["name"]:
                filtered_files.append(file_entry)
            else:
                logger.debug(
                    "Skipping mismatching fuzzy file match %s", file_entry
                )
    else:
        assert isinstance(filename_match, list)
        for file_entry in files:
            # Ensure all components are included in all result filename.
            if all(part in file_entry["name"] for part in filename_match):
                filtered_files.append(file_entry)
            else:
                logger.debug(
                    "Skipping mismatching fuzzy file match %s", file_entry
                )

    return filtered_files


def create_file(
    service: Resource,
    name: str,
    mime_type: Optional[str] = None,
    parent: Optional[str] = None,
    media_body: Optional[Union[str, MediaUpload]] = None,
) -> str:
    """Create a file in a Google Drive.

    Arguments:
        service: Google Drive service resource object
        name: User-visible name of the new Drive folder
        mime_type: Optional. MIME_TYPE of the created file. By default Google
            Drive will guess the type; see API reference for details.
        parent: Optional. ID of the parent folder. By default, the new file
            will be put into the root folder of the account's "My Drive".
        media_body: Optional. The filename of the media request body, or an
            instance of a MediaUpload object. If this is None, an empty file
            will be created. See API reference for details.

    Returns:
        ID of the created file in the Google Drive.
    """
    file_metadata: Dict[str, Any] = {
        "name": name,
    }
    if mime_type:
        file_metadata["mimeType"] = mime_type
    if parent:
        file_metadata["parents"] = [parent]

    fields: Dict[str, str] = (
        service.files()
        .create(
            body=file_metadata,
            media_body=media_body,
            fields="id",
            supportsAllDrives=True,
        )
        .execute()
    )
    return fields["id"]


def create_folder(
    service: Resource, name: str, parent: Optional[str] = None
) -> str:
    """Create a folder in a Google Drive.

    Arguments:
        service: Google Drive service resource object
        name: User-visible name of the new Drive folder
        parent: Optional. ID of the parent folder. By default, the new folder
            will be put into the root folder of the account's "My Drive".

    Returns:
        ID of the created folder in the Google Drive.
    """
    return create_file(
        service,
        name=name,
        mime_type=MIMETYPE_GOOGLE_DRIVE_FOLDER,
        parent=parent,
    )


def upload_file(
    service: Resource,
    file_path: Path,
    upload_name: Optional[str] = None,
    parent: Optional[str] = None,
) -> str:
    """Create a file with contents to a Google Drive folder.

    Arguments:
        service: Google Drive service resource object
        file_path: Path of the local source file to upload.
        upload_name: Optional. User-visible name of the uploaded file. Defaults
            to the name of the source file.
        parent: Optional. ID of the parent folder. By default, the new file
            will be put into the root folder of the account's "My Drive".

    Returns:
        ID of the created folder in the Google Drive.
    """
    if not file_path.exists():
        raise RuntimeError(f"Source file does not exist: {str(file_path)}")
    if not file_path.is_file():
        raise RuntimeError(f"Source is not a file: {str(file_path)}")

    media = MediaFileUpload(
        filename=str(file_path),
        mimetype=None,  # let the lib or GDrive guess the mime type
        chunksize=-1,  # upload in one go if possible
        resumable=True,  # resume might be needed for big files
    )
    logger.info(
        "Starting upload of %s (%s)",
        file_path,
        sizeof_fmt(file_path.stat().st_size),
    )

    uploaded_id = create_file(
        service=service,
        name=upload_name if upload_name else file_path.name,
        parent=parent,
        media_body=media,
    )

    logger.info("Uploaded file %s as fileId=%s", str(file_path), uploaded_id)
    return uploaded_id


def upload_folder_recursively(
    service: Resource, folder_path: Path, parent: Optional[str] = None
) -> str:
    """Upload a local folder into a Google Drive parent folder.

    Upload a local folder recursively into a Google Drive parent folder. Ignore
    all symlinks and special files.

    Arguments:
        service: Google Drive service resource object
        folder_path: Local folder path to upload.
        parent: Parent Google drive folder id (fileID) to upload into. If None,
            upload to My Drive's root folder.

    Returns:
        fileId of root of the uploaded folder structure.

    Raises:
        RuntimeError: If folder_path is not a directory.
    """
    if not folder_path.is_dir():
        raise RuntimeError(
            f"upload_folder_recursively must be called on directories only. "
            f'Called on "{str(folder_path)}"',
        )

    logger.info("Uploading folder recursively: %s", str(folder_path))

    # Google Drive calls the identifier "fileId" no matter if it's actually a
    # directory or file, so stick with it.
    current_dir_file_id = create_folder(
        service=service,
        # For ".", name would be empty without resolving absolute path first.
        name=folder_path.absolute().name,
        parent=parent,
    )

    files = []
    sub_dirs = []
    for entry in folder_path.iterdir():
        # Sort out file and subfolders, and make sure we ignore anything odd.
        if entry.is_symlink():
            logger.warning("Ignoring symbolic link: %s", str(entry))
        elif entry.is_dir():
            sub_dirs.append(entry)
        elif entry.is_file():
            files.append(entry)
        else:
            logger.warning(
                "Ignoring special file: %s (Could be device, FIFO, etc.)", entry
            )

    for file in files:
        upload_file(service=service, file_path=file, parent=current_dir_file_id)

    for sub_dir in sub_dirs:
        upload_folder_recursively(
            service=service, folder_path=sub_dir, parent=current_dir_file_id
        )

    logger.info(
        "Folder upload done: %s to id=%s", str(folder_path), current_dir_file_id
    )

    return current_dir_file_id


def debug_list_all_drive_contents(
    service: Resource,
    max_entries: int = 10,
    folders_only: bool = False,
    order_by: str = "recency",
) -> None:
    """Print quick overview of accessible Drives and files.

    Query all accessible Google Drives, both personal and team drives, and list
    some files in them. This is not meant as a complete content listing, but
    just to give a quick overview of what an account has access to.

    Arguments:
        service: Google Drive service resource object
        max_entries: Maximum number of files to list per Drive.
        folders_only: List folders only, skip files.
        order_by: Set ordering for files in Drives.
    """
    # "My Drive" needs special handling
    drives = [{"id": None, "name": "(My Drive)"}]
    # Add all other (team) Drives to the list
    drives.extend(list_drives(service))
    for drive in drives:
        drive_name = drive["name"]
        drive_id = drive["id"]
        print(f'Drive: "{drive_name}" (id: {drive_id})')
        if max_entries > 0:
            print(f"Files (maximum {max_entries} most recent):")
        else:
            print("Files:")
        # Search includes trashed files by default.
        search_query = "trashed = false"
        if folders_only:
            search_query += f" and mimeType='{MIMETYPE_GOOGLE_DRIVE_FOLDER}'"
        files = list_files(
            service,
            drive_id,
            max_entries=max_entries,
            query=search_query,
            order_by=order_by,
        )
        for file in files:
            file_name = file["name"]
            file_id = file["id"]
            file_mime = file["mimeType"]
            if folders_only:
                print(f"* {file_name} (id: {file_id})")
            else:
                print(f"* {file_name} (mime: {file_mime} id: {file_id})")
        print()


def cmd_overview_drives(args: argparse.Namespace, service: Resource) -> None:
    """Command entry point for "overview_drives"."""
    debug_list_all_drive_contents(
        service,
        max_entries=args.max_entries,
        folders_only=args.folders_only,
        order_by=args.order_by,
    )


def cmd_upload_file(args: argparse.Namespace, service: Resource) -> None:
    """Command entry point for "upload_file"."""
    uploaded_id = upload_file(
        service=service,
        file_path=Path(args.file),
        upload_name=args.name,
        parent=args.parent,
    )
    print(uploaded_id)


def cmd_create_folder(args: argparse.Namespace, service: Resource) -> None:
    """Command entry point for "create_folder"."""
    file_id = create_folder(service=service, name=args.name, parent=args.parent)
    logger.debug("Created folder %s with parent %s", args.name, args.parent)
    print(file_id)


def cmd_upload(args: argparse.Namespace, service: Resource) -> None:
    """Command entry point for "upload"."""
    # Validate args before uploading anything.
    if not args.recursive:
        for source in args.source_paths:
            if source.is_dir():
                args.parser.error(
                    'Source path is a directory but "--recursive" argument was '
                    "not set: %s",
                    str(source),
                )
            if source.is_symlink():
                args.parser.error(
                    "Source path is a symbolic link, not supported: %s",
                    str(source),
                )
            if not source.is_dir() and not source.is_file():
                args.parser.error(
                    "Source is a special file, not supported (Could be device, "
                    " FIFO, etc): %s",
                    str(source),
                )

    for source in args.source_paths:
        if source.is_dir():
            upload_folder_recursively(
                service=service, folder_path=source, parent=args.parent
            )
        else:
            upload_file(service=service, file_path=source, parent=args.parent)


def cmd_download_file_by_name(
    args: argparse.Namespace, service: Resource
) -> None:
    """Command entry point for "download_file_by_name"."""
    # Search includes trashed files by default.
    query_base = (
        f"mimeType != '{MIMETYPE_GOOGLE_DRIVE_FOLDER}' and trashed = false"
    )
    if args.filename:
        query_filename = f"name = '{args.filename}'"
    else:
        query_filename = " and ".join(
            f"name contains '{part}'" for part in args.filename_contains
        )
    query = f"{query_base} and {query_filename}"

    # Google Drive search is fuzzy. Filter by actual search queries.
    files = list_files_strict(
        service=service,
        drive_id=args.drive_id,
        query=query,
        filename_match=args.filename
        if args.filename
        else args.filename_contains,
    )

    if not files:
        logger.error("No matching file found.")
        sys.exit(1)
    if len(files) != 1:
        logger.error("Multiple matching files found: %s", files)
        sys.exit(1)

    file_name = files[0]["name"]
    file_id = files[0]["id"]
    logger.info(
        'Downloading file "%s" with id=%s to %s',
        file_name,
        file_id,
        args.out_filepath,
    )

    request = service.files().get_media(fileId=file_id)
    file = FileIO(args.out_filepath, mode="wb")
    downloader = MediaIoBaseDownload(file, request)
    done = False
    while done is False:
        status, done = downloader.next_chunk()
        logger.debug("Downloaded %s%%.", int(status.progress() * 100))
    logger.info("Download done.")


def cmd_find_file(args: argparse.Namespace, service: Resource) -> None:
    """Command entry point for "find"."""
    # Search includes trashed files by default.
    query_base = (
        f"mimeType != '{MIMETYPE_GOOGLE_DRIVE_FOLDER}' and trashed = false"
    )
    if args.filename:
        query_filename = f"name = '{args.filename}'"
    else:
        query_filename = " and ".join(
            f"name contains '{part}'" for part in args.filename_contains
        )
    query = f"{query_base} and {query_filename}"

    # Google Drive search is fuzzy. Filter by actual search queries.
    files = list_files_strict(
        service=service,
        drive_id=args.drive_id,
        query=query,
        filename_match=args.filename
        if args.filename
        else args.filename_contains,
    )

    print(json.dumps(files, ensure_ascii=False, indent=2))


def parse_cmdline_arguments() -> argparse.Namespace:
    """Parse the command line arguments.

    Returns:
        argparse Namespace containing the parsed command line arguments of this
        script.

    """
    parser = argparse.ArgumentParser(
        description=__doc__,
        formatter_class=argparse.RawDescriptionHelpFormatter,
    )
    log.add_logging_arguments(parser)

    subparsers = parser.add_subparsers(required=True)

    parser_overview_drives = subparsers.add_parser(
        "overview_drives",
        help="Print brief overview of accessible Google Drives.",
    )
    parser_overview_drives.set_defaults(func=cmd_overview_drives)
    parser_overview_drives.add_argument(
        "-m",
        "--max-entries",
        help=(
            "Maximum number of entries to query. Defaults to 10. Set to "
            "negative number to list without limit."
        ),
        default=10,
        type=int,
    )
    parser_overview_drives.add_argument(
        "--order-by",
        help='Choose ordering of the outputs. Defaults to "recency"',
        default="recency",
        choices=[
            "createdTime",
            "folder",
            "modifiedByMeTime",
            "modifiedTime",
            "name",
            "name_natural",
            "quotaBytesUsed",
            "recency",
            "sharedWithMeTime",
            "starred",
            "viewedByMeTime",
        ],
    )
    parser_overview_drives.add_argument(
        "--folders-only",
        help=f'List mime type "{MIMETYPE_GOOGLE_DRIVE_FOLDER}" only.',
        default=False,
        action="store_true",
    )

    parser_upload_file = subparsers.add_parser(
        "upload_file",
        help="Upload a single file and output uploaded fileId.",
    )
    parser_upload_file.set_defaults(func=cmd_upload_file)
    parser_upload_file.add_argument(
        "-f",
        "--file",
        help="Local file to upload to Google Drive.",
        type=str,
        required=True,
    )
    parser_upload_file.add_argument(
        "-p",
        "--parent",
        help=(
            "Parent folder to put the file into. Leave empty to put to My "
            "Drive's root."
        ),
        type=str,
    )
    parser_upload_file.add_argument(
        "-n",
        "--name",
        help=(
            "Name of the uploaded file in Google Drive. Leave empty to take "
            "over source file name."
        ),
        type=str,
    )

    parser_upload = subparsers.add_parser(
        "upload",
        help="Upload files and folders to a Google Drive folder.",
    )
    parser_upload.set_defaults(func=cmd_upload)
    parser_upload.add_argument(
        "source_paths",
        metavar="SOURCE_PATH",
        help=(
            "Local file or folder to upload to Google Drive. Multiple files "
            "and folders can be uploaded in one run. When uploading folders, "
            "-r must be set as well. Symbolic links and special files are not "
            "supported."
        ),
        type=Path,
        nargs="+",
    )
    parser_upload.add_argument(
        "-r",
        "--recursive",
        help="Upload directories recursively.",
        default=False,
        action="store_true",
    )
    parser_upload.add_argument(
        "-p",
        "--parent",
        help=(
            "Parent folder to upload into. Leave empty to put to My Drive's "
            "root folder."
        ),
        type=str,
    )

    parser_create_folder = subparsers.add_parser(
        "create_folder",
        help="Create a new empty folder and print its fileId.",
    )
    parser_create_folder.set_defaults(func=cmd_create_folder)
    parser_create_folder.add_argument(
        "-n",
        "--name",
        help="Name of the folder to create.",
        type=str,
        required=True,
    )
    parser_create_folder.add_argument(
        "-p",
        "--parent",
        help=(
            "Parent folder to put the new folder into. Leave empty to put to "
            "My Drive's root."
        ),
        type=str,
    )

    parser_download_file_by_name = subparsers.add_parser(
        "download_file_by_name",
        help="Download a file by name, assuming it is unique under a parent.",
    )
    parser_download_file_by_name.set_defaults(func=cmd_download_file_by_name)
    parser_download_file_by_name_filename_args = (
        parser_download_file_by_name.add_mutually_exclusive_group(required=True)
    )
    parser_download_file_by_name_filename_args.add_argument(
        "-n",
        "--filename",
        help=("Find files by unique filename."),
        type=str,
    )
    parser_download_file_by_name_filename_args.add_argument(
        "-c",
        "--filename-contains",
        help=(
            "Find file with containing a string. If set multiple times, all of "
            'the "contains" parameters must match.'
        ),
        type=str,
        action="append",
    )
    parser_download_file_by_name.add_argument(
        "-d",
        "--drive-id",
        help=(
            'ID of the Google Drive to search within. Defaults to "My Drive".'
        ),
        type=str,
    )
    parser_download_file_by_name.add_argument(
        "-o",
        "--out-filepath",
        help="Output filename or path to download the file to.",
        type=str,
        required=True,
    )

    parser_find_file = subparsers.add_parser(
        "find_file",
        help=(
            "Find files by name on a Drive. Print attributes of matching files "
            "as json."
        ),
    )
    parser_find_file.set_defaults(func=cmd_find_file)
    parser_find_file_filename_args = (
        parser_find_file.add_mutually_exclusive_group(required=True)
    )
    parser_find_file_filename_args.add_argument(
        "-n",
        "--filename",
        help="Find files by unique filename.",
        type=str,
    )
    parser_find_file_filename_args.add_argument(
        "-c",
        "--filename-contains",
        help=(
            "Find file with containing a string. If set multiple times, all of "
            'the "contains" parameters must match.'
        ),
        type=str,
        action="append",
    )
    parser_find_file.add_argument(
        "-d",
        "--drive-id",
        help=(
            'ID of the Google Drive to search within. Defaults to "My Drive".'
        ),
        type=str,
    )

    args = parser.parse_args()
    # Pass-through the parser object to sub commands for error handling.
    args.parser = parser
    log.configure_logger("", args.log, args.verbose, args.quiet)
    return args


def main() -> None:
    """Entry point into this command line tool."""
    args = parse_cmdline_arguments()

    creds, _ = google.auth.load_credentials_from_file(
        filename=os.environ[google.auth.environment_vars.CREDENTIALS]
    )
    try:
        # create drive api client
        service = build(
            "drive",
            "v3",
            credentials=creds,
            cache_discovery=False,  # can't work for file credentials
        )
        args.func(args, service)

    except HttpError as error:
        logger.error(error)
        raise


if __name__ == "__main__":
    main()