import pytest
from agent_service.llm.tool_validator import ToolCallValidator, AgentConfigError

SAMPLE_TOOLS = [
    {'name': 'get_invoices', 'parameters': {
        'state': {'type': 'string', 'optional': True},
        'limit': {'type': 'integer', 'optional': True},
        'partner_id': {'type': 'integer'},
    }},
    {'name': 'send_reminder', 'parameters': {
        'invoice_id': {'type': 'integer'},
        'message': {'type': 'string', 'optional': True},
    }},
]


def test_validator_init():
    v = ToolCallValidator(SAMPLE_TOOLS)
    assert 'get_invoices' in v._tool_map


def test_raises_on_too_many_tools():
    many_tools = [{'name': f'tool_{i}', 'parameters': {}} for i in range(9)]
    with pytest.raises(AgentConfigError, match='MAX_TOOLS_PER_AGENT'):
        ToolCallValidator(many_tools)


def test_valid_tool_call():
    v = ToolCallValidator(SAMPLE_TOOLS)
    result = v.validate({'name': 'get_invoices', 'arguments': {'partner_id': 42}})
    assert result.name == 'get_invoices'
    assert result.arguments['partner_id'] == 42


def test_strips_hallucinated_params():
    v = ToolCallValidator(SAMPLE_TOOLS)
    result = v.validate({'name': 'get_invoices', 'arguments': {
        'partner_id': 1, 'nonexistent_param': 'bad',
    }})
    assert 'nonexistent_param' not in result.arguments


def test_missing_required_param_raises():
    v = ToolCallValidator(SAMPLE_TOOLS)
    with pytest.raises(ValueError, match='partner_id'):
        v.validate({'name': 'get_invoices', 'arguments': {}})


def test_type_coercion_int():
    v = ToolCallValidator(SAMPLE_TOOLS)
    result = v.validate({'name': 'get_invoices', 'arguments': {'partner_id': '42'}})
    assert result.arguments['partner_id'] == 42


def test_unknown_tool_raises():
    v = ToolCallValidator(SAMPLE_TOOLS)
    with pytest.raises(ValueError, match='Unknown tool'):
        v.validate({'name': 'nonexistent_tool', 'arguments': {}})


def test_parse_or_fallback_returns_none_on_bad_json():
    v = ToolCallValidator(SAMPLE_TOOLS)
    result = v.parse_or_fallback('not json at all', context='test')
    assert result is None


def test_parse_or_fallback_valid_json():
    v = ToolCallValidator(SAMPLE_TOOLS)
    import json
    raw = json.dumps({'name': 'send_reminder', 'arguments': {'invoice_id': 5}})
    result = v.parse_or_fallback(raw, context='test')
    assert result is not None
    assert result.name == 'send_reminder'