#!/usr/bin/env python

"""
A simple script that removes big JPEG blobs from the contact cards on your
Nextcloud db.

:author: Fabio Manganiello <info@fabiomanganiello.com>
"""

import re
import sqlalchemy as sa
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker

Base = declarative_base()

db_url = "mysql+pymysql://user:pwd@dbhost/nextclouddb"


class Card(Base):
    __tablename__ = "oc_cards"

    id = sa.Column(sa.BigInteger, primary_key=True)
    addressbookid = sa.Column(sa.BigInteger)
    carddata = sa.Column(sa.LargeBinary)
    uri = sa.Column(sa.String)
    lastmodified = sa.Column(sa.BigInteger)
    etag = sa.Column(sa.String)
    size = sa.Column(sa.BigInteger)
    uid = sa.Column(sa.String)


def remove_photo_attributes(vcard_data):
    # Convert binary to string
    if isinstance(vcard_data, bytes):
        vcard_data = vcard_data.decode("utf-8", errors="replace")

    # Split into lines
    lines = vcard_data.split("\n")
    result_lines = []

    i = 0
    while i < len(lines):
        line = lines[i]

        # Check if this is a PHOTO attribute
        if line.startswith("PHOTO;"):
            # Skip this line and any continuation lines (starting with space)
            i += 1
            while i < len(lines) and (
                lines[i].startswith(" ") or lines[i].startswith("\t")
            ):
                i += 1
        else:
            # Keep this line
            result_lines.append(line)
            i += 1

    # Join back into a string
    return "\n".join(result_lines).encode("utf-8")


def update_cards():
    engine = sa.create_engine(db_url)
    Session = sessionmaker(bind=engine, autocommit=False)
    session = Session()

    try:
        # Process in batches to avoid memory issues
        batch_size = 100
        offset = 0

        while True:
            cards = (
                session.query(Card)
                .order_by(Card.id)
                .offset(offset)
                .limit(batch_size)
                .all()
            )
            if not cards:
                break

            for card in cards:
                new_carddata = remove_photo_attributes(card.carddata)
                if new_carddata != card.carddata:
                    card.carddata = new_carddata
                    # Update size field to reflect new size
                    print(
                        f"Card: id={card.id} old_size={card.size / 1000}KB new_size={len(new_carddata) / 1000}KB"
                    )
                    card.size = len(new_carddata)
                    # Update etag (optional, depends on how Nextcloud generates etags)
                    # card.etag = generate_new_etag()

            session.commit()
            offset += batch_size
            print(f"Processed {offset} records")

    except Exception as e:
        session.rollback()
        print(f"Error: {e}")
    finally:
        session.close()


if __name__ == "__main__":
    update_cards()