#!/usr/bin/env python3
"""Read and validate the SPARC DROID JSONL + HDF5 release."""

from __future__ import annotations

import argparse
from contextlib import ExitStack
import json
from pathlib import Path
from typing import Iterable, Iterator, Mapping, Sequence

import h5py
import numpy as np


VIEW_DIRS = {
    "left": "droid_lerobot_left",
    "right": "droid_lerobot_right",
}


def view_root(repo_root: str | Path, view: str) -> Path:
    try:
        dirname = VIEW_DIRS[view]
    except KeyError as exc:
        raise ValueError(f"view must be one of {sorted(VIEW_DIRS)}, got {view!r}") from exc
    root = Path(repo_root) / "data" / dirname
    if not root.is_dir():
        raise FileNotFoundError(root)
    return root


def manifest_paths(repo_root: str | Path, view: str) -> list[Path]:
    """Return a non-duplicating manifest list for a camera view."""
    root = view_root(repo_root, view)
    consolidated = root / "annotations.jsonl"
    if consolidated.is_file():
        return [consolidated]
    nodes = sorted(root.glob("annotations_node*.jsonl"))
    if not nodes:
        raise FileNotFoundError(f"No annotation manifests found under {root}")
    return nodes


def iter_annotations(repo_root: str | Path, view: str) -> Iterator[dict]:
    for manifest in manifest_paths(repo_root, view):
        with manifest.open("r", encoding="utf-8") as stream:
            for line_number, line in enumerate(stream, 1):
                if not line.strip():
                    continue
                try:
                    yield json.loads(line)
                except json.JSONDecodeError as exc:
                    raise ValueError(f"Invalid JSON at {manifest}:{line_number}") from exc


def storage_reference(repo_root: str | Path, annotation: Mapping, view: str) -> tuple[Path, str]:
    arrays = annotation.get("arrays") or {}
    storage = arrays.get("storage") or {}
    if "path" not in storage or "group" not in storage:
        raise KeyError(f"Annotation {annotation.get('annotation_id')} has no HDF5 storage reference")
    shard = view_root(repo_root, view) / storage["path"]
    return shard, storage["group"]


def load_arrays(
    repo_root: str | Path,
    annotation: Mapping,
    view: str,
    keys: Sequence[str] | None = None,
) -> dict[str, np.ndarray]:
    """Load selected arrays, copying them out before closing the HDF5 file."""
    shard, group_name = storage_reference(repo_root, annotation, view)
    with h5py.File(shard, "r") as handle:
        if group_name not in handle:
            raise KeyError(f"Missing group {group_name!r} in {shard}")
        group = handle[group_name]
        selected = list(group.keys()) if keys is None else list(keys)
        missing = [key for key in selected if key not in group]
        if missing:
            raise KeyError(f"Arrays absent from {group_name}: {missing}")
        return {key: np.asarray(group[key]) for key in selected}


def verify(repo_root: str | Path, views: Iterable[str] = ("left", "right")) -> dict:
    """Validate IDs and every JSON-to-HDF5 path/group reference."""
    result = {}
    for view in views:
        annotation_ids: set[str] = set()
        trajectory_ids: set[str] = set()
        rows = 0
        with ExitStack() as stack:
            handles: dict[Path, h5py.File] = {}
            for annotation in iter_annotations(repo_root, view):
                rows += 1
                annotation_id = str(annotation["annotation_id"])
                if annotation_id in annotation_ids:
                    raise ValueError(f"Duplicate annotation_id in {view}: {annotation_id}")
                annotation_ids.add(annotation_id)
                trajectory_ids.add(str(annotation["source"]["trajectory_id"]))
                shard, group_name = storage_reference(repo_root, annotation, view)
                if not shard.is_file():
                    raise FileNotFoundError(shard)
                if shard not in handles:
                    handles[shard] = stack.enter_context(h5py.File(shard, "r"))
                if group_name not in handles[shard]:
                    raise KeyError(f"Missing group {group_name!r} in {shard}")
        result[view] = {
            "annotation_rows": rows,
            "unique_annotation_ids": len(annotation_ids),
            "unique_trajectories": len(trajectory_ids),
        }
    return result


def main() -> None:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("repo_root", type=Path)
    parser.add_argument("--view", choices=sorted(VIEW_DIRS), default="right")
    parser.add_argument("--limit", type=int, default=3)
    parser.add_argument("--show-arrays", action="store_true")
    parser.add_argument("--verify", action="store_true")
    args = parser.parse_args()

    if args.verify:
        print(json.dumps(verify(args.repo_root), indent=2, sort_keys=True))
        return

    for index, annotation in enumerate(iter_annotations(args.repo_root, args.view)):
        if index >= args.limit:
            break
        summary = {
            "annotation_id": annotation["annotation_id"],
            "trajectory_id": annotation["source"]["trajectory_id"],
            "source_uuid": annotation["source"].get("source_uuid"),
            "subtask_index": annotation["source"]["subtask_index"],
            "instruction": annotation["task"]["instruction"],
            "selection_score": annotation["selection"]["score"],
        }
        print(json.dumps(summary, indent=2, ensure_ascii=False))
        if args.show_arrays:
            arrays = load_arrays(args.repo_root, annotation, args.view)
            print({key: {"shape": value.shape, "dtype": str(value.dtype)} for key, value in arrays.items()})


if __name__ == "__main__":
    main()