import json
from pathlib import Path

import pyarrow.parquet as pq

from ._state import fingerprint
from ._vectors import validate_vectors
from .config import PRETRAINED_DIMENSION, PRETRAINED_MODEL, TARGETS


def load_vectors(graph, targets, directory, batch_size, limit):
    root = Path(directory)
    manifest = json.loads((root / 'manifest.json').read_text())
    source = fingerprint({'release': manifest['source_id'], 'model': PRETRAINED_MODEL, 'dimension': PRETRAINED_DIMENSION, 'storage': 'float16'})
    counts = {}
    for name in targets:
        target = TARGETS[name]
        graph.check_source(target, target.property, source)
        paths = sorted((root / 'parquet').glob(target.files))
        if not paths:
            raise FileNotFoundError(target.files)
        written = 0
        for path in paths:
            for batch in pq.ParquetFile(path).iter_batches(batch_size=batch_size, columns=[target.key, target.column]):
                items = [row for row in batch.to_pylist() if row[target.column] is not None]
                missing = graph.missing(target, [row[target.key] for row in items], target.property)
                pending = [row for row in items if row[target.key] in missing]
                if limit:
                    pending = pending[:limit - written]
                if pending:
                    vectors = validate_vectors([row[target.column] for row in pending], PRETRAINED_DIMENSION)
                    graph.write(target, target.property, source, [{'key': row[target.key], 'vector': vector} for row, vector in zip(pending, vectors)])
                    written += len(pending)
                if limit and written >= limit:
                    break
            if limit and written >= limit:
                break
        counts[name] = written
        print(json.dumps({'target': name, 'vectors_added': written}), flush=True)
    return counts