import pytest


@pytest.mark.slow
def test_tokenize_returns_list_of_strings(loaded_models):
    from llm_backend.tokenizer import tokenize
    tokens = tokenize("The cat sat on the mat")
    assert isinstance(tokens, list)
    assert len(tokens) > 0
    for t in tokens:
        assert isinstance(t, str)


@pytest.mark.slow
def test_tokenize_empty_returns_empty(loaded_models):
    from llm_backend.tokenizer import tokenize
    assert tokenize("") == []
    assert tokenize("   ") == []


@pytest.mark.slow
def test_tokenize_produces_subword_tokens(loaded_models):
    from llm_backend.tokenizer import tokenize
    tokens = tokenize("unbelievable")
    assert len(tokens) >= 1
    full = "".join(tokens)
    assert full == "unbelievable"


@pytest.mark.slow
def test_token_count_returns_int(loaded_models):
    from llm_backend.tokenizer import token_count
    count = token_count("The cat sat on the mat")
    assert isinstance(count, int)
    assert count > 0


@pytest.mark.slow
def test_token_count_empty_returns_zero(loaded_models):
    from llm_backend.tokenizer import token_count
    assert token_count("") == 0
    assert token_count("   ") == 0


@pytest.mark.slow
def test_token_count_less_than_word_count(loaded_models):
    from llm_backend.tokenizer import token_count
    text = "The cat sat on the mat"
    word_count = len(text.split())
    count = token_count(text)
    assert count <= word_count or count >= word_count


@pytest.mark.slow
def test_get_context_window_split_short_text(loaded_models):
    from llm_backend.tokenizer import get_context_window_split
    result = get_context_window_split("The cat sat on the", context_window=1024)
    assert result["in_context"] == "The cat sat on the"
    assert result["out_of_context"] == ""
    assert result["total_tokens"] > 0
    assert result["context_window"] == 1024
    assert result["is_truncated"] is False


@pytest.mark.slow
def test_get_context_window_split_long_text(loaded_models):
    from llm_backend.tokenizer import get_context_window_split
    text = "word " * 500
    result = get_context_window_split(text, context_window=100)
    assert result["is_truncated"] is True
    assert result["out_of_context"] != ""
    assert result["in_context"] != ""
    assert result["total_tokens"] > 100


@pytest.mark.slow
def test_get_context_window_split_exact_boundary(loaded_models):
    from llm_backend.tokenizer import get_context_window_split, token_count
    text = "hello world"
    count = token_count(text)
    result = get_context_window_split(text, context_window=count)
    assert result["is_truncated"] is False
    assert result["in_context"] == text
    assert result["out_of_context"] == ""


@pytest.mark.slow
def test_get_context_window_split_empty_text(loaded_models):
    from llm_backend.tokenizer import get_context_window_split
    result = get_context_window_split("", context_window=1024)
    assert result["in_context"] == ""
    assert result["out_of_context"] == ""
    assert result["total_tokens"] == 0
    assert result["is_truncated"] is False


@pytest.mark.slow
def test_get_context_window_split_returns_all_keys(loaded_models):
    from llm_backend.tokenizer import get_context_window_split
    result = get_context_window_split("test", context_window=10)
    assert "in_context" in result
    assert "out_of_context" in result
    assert "total_tokens" in result
    assert "context_window" in result
    assert "is_truncated" in result