import argparse
from pathlib import Path

import psycopg


def fetch_emails(pg_host, pg_port, pg_db, pg_user, pg_password, table_name, domain):
    conn = psycopg.connect(
        host=pg_host,
        port=pg_port,
        dbname=pg_db,
        user=pg_user,
        password=pg_password,
        connect_timeout=10,
    )
    try:
        with conn, conn.cursor() as cur:
            cur.execute(
                f"select distinct lower(email) from {table_name} where lower(email) like %s order by lower(email)",
                (f"%@{domain.lower()}",),
            )
            return [row[0] for row in cur.fetchall()]
    finally:
        conn.close()


def write_sql(output_path, emails, source_meta):
    lines = []
    for email in emails:
        safe = email.replace("'", "''")
        source = source_meta.replace("'", "''")
        lines.append(
            f"INSERT OR IGNORE INTO address(name, source_meta) VALUES('{safe}', '{source}');"
        )
    Path(output_path).write_text("\n".join(lines), encoding="utf-8")


def main():
    parser = argparse.ArgumentParser(description="Export domain mailboxes from PostgreSQL into Cloudflare D1 import SQL.")
    parser.add_argument("--pg-host", required=True)
    parser.add_argument("--pg-port", type=int, required=True)
    parser.add_argument("--pg-db", required=True)
    parser.add_argument("--pg-user", required=True)
    parser.add_argument("--pg-password", required=True)
    parser.add_argument("--table", default="registered_accounts")
    parser.add_argument("--domain", required=True)
    parser.add_argument("--source-meta", default="pg_import")
    parser.add_argument("--output", required=True)
    args = parser.parse_args()

    emails = fetch_emails(
        args.pg_host,
        args.pg_port,
        args.pg_db,
        args.pg_user,
        args.pg_password,
        args.table,
        args.domain,
    )
    write_sql(args.output, emails, args.source_meta)
    print(f"exported={len(emails)} output={args.output}")


if __name__ == "__main__":
    main()