"""extract_usage: разбор форматов usage разных провайдеров."""
import sys
import os

sys.path.insert(0, os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), "app"))

from usage_utils import extract_usage

EMPTY = {"input_tokens": None, "output_tokens": None, "total_tokens": None, "usage_json": None}


def test_openai_shape():
    u = extract_usage({"choices": [], "usage": {"prompt_tokens": 10, "completion_tokens": 5, "total_tokens": 15}})
    assert u["input_tokens"] == 10
    assert u["output_tokens"] == 5
    assert u["total_tokens"] == 15
    assert u["usage_json"] == '{"completion_tokens": 5, "prompt_tokens": 10, "total_tokens": 15}'


def test_anthropic_shape_total_computed():
    u = extract_usage({"usage": {"input_tokens": 7, "output_tokens": 3}})
    assert u["input_tokens"] == 7
    assert u["output_tokens"] == 3
    assert u["total_tokens"] == 10  # точная сумма отчётных значений, не оценка


def test_camel_case_shape():
    u = extract_usage({"usage": {"promptTokens": 4, "completionTokens": 2, "totalTokens": 6}})
    assert (u["input_tokens"], u["output_tokens"], u["total_tokens"]) == (4, 2, 6)


def test_missing_usage_all_none():
    assert extract_usage({"choices": []}) == EMPTY
    assert extract_usage({"usage": None}) == EMPTY
    assert extract_usage({}) == EMPTY


def test_non_dict_resp():
    assert extract_usage(None) == EMPTY
    assert extract_usage("error") == EMPTY


def test_zero_usage_treated_as_unknown():
    # полностью нулевой usage = провайдер не отдал данные → NULL, не нули
    u = extract_usage({"usage": {"prompt_tokens": 0, "completion_tokens": 0, "total_tokens": 0}})
    assert u == EMPTY


def test_string_encoded_usage():
    u = extract_usage({"usage": '{"prompt_tokens": 8, "completion_tokens": 1, "total_tokens": 9}'})
    assert (u["input_tokens"], u["output_tokens"], u["total_tokens"]) == (8, 1, 9)


def test_partial_total_only():
    u = extract_usage({"usage": {"total_tokens": 42}})
    assert u["input_tokens"] is None
    assert u["output_tokens"] is None
    assert u["total_tokens"] == 42


def test_garbage_values_ignored():
    u = extract_usage({"usage": {"prompt_tokens": "много", "completion_tokens": True, "total_tokens": None}})
    assert u == EMPTY


def test_usage_json_roundtrip():
    raw = {"prompt_tokens": 10, "completion_tokens": 5, "total_tokens": 15, "extra": {"x": 1}}
    u = extract_usage({"usage": raw})
    import json
    assert json.loads(u["usage_json"]) == raw