"""
Shared append-only ingest harness for a ziplime PIT dataset.

Reads `recipe.fetch(since)`, stamps `ingested_at`, drops byte-identical duplicates of
existing (entity_id, event_date, knowledge_date) rows, and **appends** to the Delta table.
It never issues UPDATE/DELETE/MERGE — append-only is the PIT invariant the linter enforces.
"""
from __future__ import annotations
import argparse, hashlib
from datetime import datetime, timezone
from pathlib import Path

import polars as pl
from deltalake import DeltaTable, write_deltalake

import recipe

TABLE_URI = str(Path(__file__).parent / "data" / "data_bundle" /
                "yahoo_finance_daily_data" / "1784755946" / "data.delta")


def _row_hash(df: pl.DataFrame) -> pl.Series:
    cols = [c for c in df.columns if c != "ingested_at"]
    return df.select(cols).hash_rows().cast(pl.Utf8)


async def main(since: datetime) -> None:
    fresh = await recipe.fetch(since)
    if fresh.is_empty():
        print("recipe returned no rows; nothing to append")
        return

    fresh = fresh.with_columns(
        pl.lit(datetime.now(timezone.utc)).alias("ingested_at"),
    )

    try:
        existing = pl.from_arrow(DeltaTable(TABLE_URI).to_pyarrow_table())
        seen = set(_row_hash(existing).to_list())
        fresh = fresh.filter(~_row_hash(fresh).is_in(seen))
    except Exception:
        pass  # first ingest / fresh table

    if fresh.is_empty():
        print("no new or revised rows after dedup")
        return

    write_deltalake(TABLE_URI, fresh.to_arrow(), mode="append")
    print(f"appended {len(fresh)} rows to {TABLE_URI}")


if __name__ == "__main__":
    ap = argparse.ArgumentParser()
    ap.add_argument("--since", default="2025-01-01")
    args = ap.parse_args()
    import asyncio
    asyncio.run(main(datetime.fromisoformat(args.since).replace(tzinfo=timezone.utc)))