import json
import pytest
from trace_aggpy import main

@pytest.fixture
def sample_read_data():
    return [
        {"corr_id": "c1", "timestamp": 1.0, "cpu": 0, "field_tag": "mult", "retry_free": True},
        {"corr_id": "c1", "timestamp": 1.5, "cpu": 1, "field_tag": "shift", "retry_free": False},
        {"corr_id": "c1", "timestamp": 2.0, "cpu": 0, "field_tag": "mult", "retry_free": True},
        {"corr_id": "c1", "timestamp": 3.5, "cpu": 1, "field_tag": "nsec_base", "retry_free": True}
    ]

@pytest.fixture
def retry_free_only_data():
    return [
        {"corr_id": "c2", "timestamp": 0.5, "cpu": 0, "field_tag": "mult", "retry_free": True},
        {"corr_id": "c2", "timestamp": 1.5, "cpu": 0, "field_tag": "shift", "retry_free": True}
    ]

def test_analyze_reads_basic(sample_read_data):
    result = main.analyze_reads("c1", sample_read_data)
    assert isinstance(result, main.ReadAnalysisResult)
    as_json = result.to_json()
    assert as_json["corr_id"] == "c1"
    assert isinstance(as_json["retry_free_count"], int)
    assert isinstance(as_json["duration_metrics"], dict)
    assert isinstance(as_json["summary_table"], list)

def test_retry_free_count(retry_free_only_data):
    result = main.analyze_reads("c2", retry_free_only_data)
    j = result.to_json()
    assert j["retry_free_count"] == 2
    assert len(j["summary_table"]) >= 1

def test_invalid_input_types():
    with pytest.raises(AssertionError):
        main.analyze_reads(123, [])
    with pytest.raises(AssertionError):
        main.analyze_reads("cid", "notalist")

@pytest.mark.parametrize("events", [[], [{"corr_id": "x", "timestamp": 1.0, "cpu": 0, "field_tag": "f", "retry_free": False}]])
def test_empty_and_single_event(events):
    result = main.analyze_reads("x", events)
    data = result.to_json()
    assert "corr_id" in data
    assert isinstance(data["duration_metrics"], dict)
    assert isinstance(data["summary_table"], list)

def test_to_json_structure(sample_read_data):
    result = main.analyze_reads("c1", sample_read_data)
    json_data = result.to_json()
    serialized = json.dumps(json_data)
    parsed = json.loads(serialized)
    assert parsed["corr_id"] == json_data["corr_id"]