# wikiget - CLI tool for downloading files from Wikimedia sites
# Copyright (C) 2018-2021 Cody Logan and contributors
# SPDX-License-Identifier: GPL-3.0-or-later
#
# Wikiget is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Wikiget is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Wikiget. If not, see <https://www.gnu.org/licenses/>.

import argparse
import logging
import sys

from . import DEFAULT_SITE, DEFAULT_PATH, wikiget_version
from .dl import download


def main():
    """
    Main entry point for console script. Automatically compiled by setuptools
    when installed with `pip install` or `python setup.py install`.
    """

    parser = argparse.ArgumentParser(description="""
                                     A tool for downloading files from
                                     MediaWiki sites using the file name or
                                     description page URL
                                     """,
                                     epilog="""
                                     Copyright (C) 2018-2021 Cody Logan
                                     and contributors.
                                     License GPLv3+: GNU GPL version 3 or later
                                     <http://www.gnu.org/licenses/gpl.html>.
                                     This is free software; you are free to
                                     change and redistribute it under certain
                                     conditions. There is NO WARRANTY, to the
                                     extent permitted by law.
                                     """)
    parser.add_argument("FILE", help="""
                        name of the file to download with the File:
                        prefix, or the URL of its file description page
                        """)
    parser.add_argument("-V", "--version", action="version",
                        version=f"%(prog)s {wikiget_version}")
    message_options = parser.add_mutually_exclusive_group()
    message_options.add_argument("-q", "--quiet",
                                 help="suppress warning messages",
                                 action="store_true")
    message_options.add_argument("-v", "--verbose",
                                 help="print detailed information; "
                                 "use -vv for even more detail",
                                 action="count", default=0)
    parser.add_argument("-f", "--force",
                        help="force overwriting existing files",
                        action="store_true")
    parser.add_argument("-s", "--site", default=DEFAULT_SITE,
                        help="MediaWiki site to download from "
                        "(default: %(default)s)")
    parser.add_argument("-p", "--path", default=DEFAULT_PATH,
                        help="MediaWiki site path, where api.php is located "
                        "(default: %(default)s)")
    parser.add_argument("--username", default="",
                        help="MediaWiki site username, for private wikis")
    parser.add_argument("--password", default="",
                        help="MediaWiki site password, for private wikis")
    output_options = parser.add_mutually_exclusive_group()
    output_options.add_argument("-o", "--output",
                                help="write download to OUTPUT")
    output_options.add_argument("-a", "--batch",
                                help="treat FILE as a textfile containing "
                                "multiple files to download, one URL or "
                                "filename per line", action="store_true")
    parser.add_argument("-l", "--logfile", default="",
                        help="save log output to LOGFILE")

    args = parser.parse_args()

    loglevel = logging.WARNING
    if args.verbose >= 2:
        # this includes API and library messages
        loglevel = logging.DEBUG
    elif args.verbose >= 1:
        loglevel = logging.INFO
    elif args.quiet:
        loglevel = logging.ERROR

    # configure logging:
    # console log level is set via -v, -vv, and -q options
    # file log level is always info (TODO: add debug option)
    if args.logfile:
        # log to console and file
        logging.basicConfig(
            level=logging.INFO,
            format="%(asctime)s [%(levelname)-7s] %(message)s",
            filename=args.logfile
        )

        console = logging.StreamHandler()
        # TODO: even when loglevel is set to logging.DEBUG,
        # debug messages aren't printing to console
        console.setLevel(loglevel)
        console.setFormatter(
            logging.Formatter("[%(levelname)s] %(message)s")
        )
        logging.getLogger("").addHandler(console)
    else:
        # log only to console
        logging.basicConfig(
            level=loglevel,
            format="[%(levelname)s] %(message)s"
        )

    # log events are appended to the file if it already exists,
    # so note the start of a new download session
    logging.info(f"Starting download session using wikiget {wikiget_version}")
    # logging.info(f"Log level is set to {loglevel}")

    if args.batch:
        # batch download mode
        input_file = args.FILE
        dl_list = []

        logging.info(f"Using batch file '{input_file}'.")

        try:
            fd = open(input_file, "r")
        except IOError as e:
            logging.error("File could not be read. "
                          "The following error was encountered:")
            logging.error(e)
            sys.exit(1)
        else:
            with fd:
                # store file contents in memory in case something
                # happens to the file while we're downloading
                for _, line in enumerate(fd):
                    dl_list.append(line)

        # TODO: validate file contents before download process starts
        for line_num, url in enumerate(dl_list, start=1):
            url = url.strip()
            # keep track of batch file line numbers for
            # debugging/logging purposes
            logging.info(f"Downloading '{url}' at line {line_num}:")
            download(url, args)
    else:
        # single download mode
        dl = args.FILE
        download(dl, args)