import argparse
import os

import numpy as np


def iter_transitions(data_dir: str):
    shard_files = sorted(
        f for f in os.listdir(data_dir) if f.startswith("shard_") and f.endswith(".npz")
    )
    for name in shard_files:
        path = os.path.join(data_dir, name)
        data = np.load(path, allow_pickle=True)
        frames_list = data["frames"]
        w_list = data["w"]
        h_list = data["h"]

        for i in range(len(frames_list)):
            frames = frames_list[i]
            w = int(w_list[i])
            h = int(h_list[i])
            for t in range(frames.shape[0] - 1):
                yield w, h, frames[t], frames[t + 1]


def main() -> None:
    parser = argparse.ArgumentParser()
    parser.add_argument("--data", default="./nca_dataset_set2/data")
    parser.add_argument("--limit", type=int, default=5)
    args = parser.parse_args()

    for i, (w, h, frame_t, frame_t1) in enumerate(iter_transitions(args.data), start=1):
        print(f"sample={i} w={w} h={h} unique_t={np.unique(frame_t).size}")
        if i >= args.limit:
            break


if __name__ == "__main__":
    main()