#! /usr/bin/env python3

import sys
import argparse
import traceback

from xenu_nntp.config    import Config
from xenu_nntp.db        import Database
from xenu_nntp.newsgroup import Newsgroup
from xenu_nntp.mbox      import MBoxReader

class ImportException(Exception):
    def __init__(self, path: str, line: int, error: str):
        self.path  = path
        self.line  = line
        self.error = error

    def __str__(self):
        return "Error importing %s at line %d: %s" % (
            self.path, self.line, self.error
        )

class Importer():
    def __init__(self, db: Database, newsgroup: Newsgroup, args):
        self.db        = db
        self.newsgroup = newsgroup
        self.args      = args

    def import_mbox_file(db: Database, newsgroup: Newsgroup, mboxfile: str):
        reader = MBoxReader(mboxfile)

        try:
            for message in reader.messages():
                if self.args.verbose and not self.args.quiet:
                    print(f"Importing message {message.id}")
                    
                db.add(message)

                db.execute(f'insert into newsgroup_message values (%s, %s)',
                    (newsgroup.id, message.id))
        except Exception as e:
            raise ImportException(mboxfile, reader.line, str(e))

parser = argparse.ArgumentParser(description='Create new account')
parser.add_argument('--dry-run',           action='store_true', help='Do not commit to database')
parser.add_argument('--quiet',             action='store_true', help='Do not print errors')
parser.add_argument('--verbose',           action='store_true', help='Print messages when importing files and messages')
parser.add_argument('--ignore-errors',     action='store_true', help='Do not exit on encountering errors')
parser.add_argument('--config-file', '-f', type=str,            help='Specify a configuration file location')
parser.add_argument('newsgroup',           type=str,            help='Name of newsgroup to ingest articles into')
parser.add_argument('mboxfile',            type=str, nargs='+', help='mbox file to ingest')

args = parser.parse_args()

config    = Config.load(args.config_file)
db        = Database.from_config(config)
newsgroup = db.get(Newsgroup, {'name': args.newsgroup})

db.execute("begin transaction")

for mboxfile in args.mboxfile:
    if args.verbose and not args.quiet:
        print(f"Importing mbox file {mboxfile}")

    try:
        import_mbox_file(db, newsgroup, mboxfile)
    except ImportException as e:
        if not args.quiet:
            print(str(e), file=sys.stderr)

        if not args.ignore_errors:
            exit(1)

if not args.dry_run:
    db.commit()