import csv
import time
from collections import defaultdict
from itertools import islice
from pathlib import Path


def _chunked(iterable, size):
    it = iter(iterable)
    while chunk := list(islice(it, size)):
        yield chunk


def delete_orders(
    table_client,
    csv_path: Path,
    batch_size: int,
    delay_ms: int,
) -> int:
    by_partition: dict[str, list[dict]] = defaultdict(list)

    with open(csv_path, newline="") as f:
        reader = csv.DictReader(f)
        for row in reader:
            pk = row["PartitionKey"]
            rk = row["RowKey"]
            by_partition[pk].append({"PartitionKey": pk, "RowKey": rk})

    total_deleted = 0
    for pk, entities in by_partition.items():
        for batch in _chunked(entities, batch_size):
            operations = [("delete", e) for e in batch]
            table_client.submit_transaction(operations)
            total_deleted += len(batch)
            if delay_ms > 0:
                time.sleep(delay_ms / 1000.0)

    print(f"Deleted {total_deleted} orders across {len(by_partition)} partitions")
    return total_deleted