"""Training rows: `lycaon-debug decide export` output, pw-decide-row/1.

row.schema.json beside this file describes the shape. A row is one turn
decision: the state the engine read, the candidates the turn offered, what
the engine answered, and what the session then did. Every consumer reads
option sets from the row's `offered` candidates and option texts from the
corpus, so a label is always read against the options the host had.
"""

import json

SCHEMA = "pw-decide-row/1"


def load(path):
    """Every row of a JSON-lines file, refusing any row of another shape."""
    rows = []
    with open(path, encoding="utf-8") as fh:
        for n, line in enumerate(fh, 1):
            if not line.strip():
                continue
            row = json.loads(line)
            if row.get("schema") != SCHEMA:
                raise ValueError("%s:%d: schema %r, want %r" % (path, n, row.get("schema"), SCHEMA))
            rows.append(row)
    return rows


def engine_answered(row):
    """The engine chose what this turn carried, so a tool it preloaded and the session
    then called is not an independent label."""
    return row["engine"]["state"] == "answered"


def truth_tools(row):
    """The loadable tools the turn needed: the ones it called or asked for by name."""
    return set(row["labels"]["tools"]) | set(row["labels"]["requested_names"])