import argparse
import csv
import datetime
import logging
import sys

from app import app
from app.extensions import db
from app.models import Group, Origin, Proxy, BridgeConf, Alarm

models = {
    "group": Group,
    "origin": Origin,
    "proxy": Proxy,
    "bridge": BridgeConf,
    "alarm": Alarm
}


def export(model: db.Model):
    out = csv.writer(sys.stdout)
    out.writerow(model.csv_header())
    for r in model.query.all():
        out.writerow(r.csv_row())


def impot(model: db.Model):
    first = True
    header = model.csv_header()
    try:
        for line in csv.reader(sys.stdin):
            if first:
                if line != header:
                    logging.error("CSV header mismatch")
                    sys.exit(1)
                first = False
                continue
            x = model()
            for i in range(len(header)):
                if header[i] in ["added", "updated", "destroyed", "deprecated", "last_updated", "terraform_updated"]:
                    if line[i] == "":
                        line[i] = None
                    else:
                        line[i] = datetime.datetime.strptime(line[i], "%Y-%m-%d %H:%M:%S.%f")
                setattr(x, header[i], line[i])
            db.session.add(x)
        db.session.commit()
        logging.info("Import completed successfully")
    except Exception as e:
        logging.exception(e)
        db.session.rollback()


class DbCliHandler:
    @classmethod
    def add_subparser_to(cls, subparsers: argparse._SubParsersAction) -> None:
        parser = subparsers.add_parser("db", help="database operations")
        parser.add_argument("--export", choices=["group", "origin", "proxy", "bridge"],
                            help="export data to CSV format")
        parser.add_argument("--import", choices=["group", "origin", "proxy", "bridge"],
                            help="import data from CSV format", dest="impot")
        parser.set_defaults(cls=cls)

    def __init__(self, args):
        self.args = args

    def run(self):
        with app.app_context():
            if self.args.export:
                export(models[self.args.export])
            elif self.args.impot:
                impot(models[self.args.impot])
            else:
                logging.error("No action requested")