import argparse
import os
import tempfile
from typing import Any

from django.conf import settings
from django.core.management.base import CommandError, CommandParser
from typing_extensions import override

from zerver.data_import.slack import do_convert_directory, do_convert_zipfile
from zerver.lib.management import ZulipBaseCommand


class Command(ZulipBaseCommand):
    help = """Convert the Slack data into Zulip data format."""

    @override
    def add_arguments(self, parser: CommandParser) -> None:
        parser.add_argument(
            "slack_data_path",
            nargs="+",
            metavar="<Slack data path>",
            help="Zipped Slack data or directory",
        )

        parser.add_argument(
            "--token", metavar="<slack_token>", help="Bot user OAuth token, starting xoxb-"
        )

        parser.add_argument(
            "--output", dest="output_dir", help="Directory to write exported data to."
        )

        parser.add_argument(
            "--processes",
            default=settings.DEFAULT_DATA_EXPORT_IMPORT_PARALLELISM,
            help="Processes to use in exporting UserMessage objects in parallel",
        )

        parser.add_argument(
            "--no-convert-slack-threads",
            action="store_true",
            help="If specified, do not convert Slack threads to separate Zulip topics",
        )

        parser.formatter_class = argparse.RawTextHelpFormatter

    @override
    def handle(self, *args: Any, **options: Any) -> None:
        output_dir = options["output_dir"]
        if output_dir is None:
            output_dir = tempfile.mkdtemp(prefix="converted-slack-data-")
        else:
            output_dir = os.path.realpath(output_dir)

        token = options["token"]
        if token is None:
            raise CommandError("Enter Slack legacy token!")

        num_processes = int(options["processes"])
        if num_processes < 1:
            raise CommandError("You must have at least one process.")

        for path in options["slack_data_path"]:
            if not os.path.exists(path):
                raise CommandError(f"Slack data file or directory not found: '{path}'")

            print("Converting data ...")
            convert_slack_threads = not options["no_convert_slack_threads"]
            if os.path.isdir(path):
                do_convert_directory(
                    path,
                    output_dir,
                    token,
                    processes=num_processes,
                    convert_slack_threads=convert_slack_threads,
                )
            elif os.path.isfile(path) and path.endswith(".zip"):
                do_convert_zipfile(
                    path,
                    output_dir,
                    token,
                    processes=num_processes,
                    convert_slack_threads=convert_slack_threads,
                )
            else:
                raise ValueError(f"Don't know how to import Slack data from {path}")
