"""Focused coverage-helper tests for titan-iac quality modules."""

from __future__ import annotations

import textwrap
from pathlib import Path

import pytest

from testing.quality_coverage import compute_workspace_line_coverage, run_check


def test_compute_workspace_line_coverage_handles_missing_xml(tmp_path: Path) -> None:
    """Missing coverage XML should produce a zero workspace coverage score."""

    contract = {"coverage": {"tracked_files": ["managed.py"]}}
    assert (
        compute_workspace_line_coverage(contract, tmp_path, tmp_path / "missing.xml")
        == 0.0
    )


def test_compute_workspace_line_coverage_averages_present_tracked_files(
    tmp_path: Path,
) -> None:
    """Workspace coverage should average only tracked files that appear in the report."""

    coverage_xml = tmp_path / "coverage.xml"
    coverage_xml.write_text(
        textwrap.dedent(
            """\
            <coverage>
              <packages>
                <package>
                  <classes>
                    <class filename="alpha.py" line-rate="1.0" branch-rate="1.0" />
                    <class filename="beta.py" line-rate="0.5" branch-rate="1.0" />
                  </classes>
                </package>
              </packages>
            </coverage>
            """
        ),
        encoding="utf-8",
    )

    contract = {"coverage": {"tracked_files": ["alpha.py", "beta.py", "missing.py"]}}
    assert compute_workspace_line_coverage(contract, tmp_path, coverage_xml) == 75.0


def test_run_check_keeps_relative_names_when_source_roots_do_not_match(
    tmp_path: Path,
) -> None:
    """Relative filenames should remain relative when no declared source root contains them."""

    coverage_xml = tmp_path / "coverage.xml"
    unmatched_root = tmp_path / "other-root"
    unmatched_root.mkdir()
    coverage_xml.write_text(
        textwrap.dedent(
            f"""\
            <coverage>
              <sources>
                <source>{unmatched_root}</source>
              </sources>
              <packages>
                <package>
                  <classes>
                    <class filename="relative.py" line-rate="0.80" branch-rate="1.0" />
                  </classes>
                </package>
              </packages>
            </coverage>
            """
        ),
        encoding="utf-8",
    )

    issues = run_check(
        {"coverage": {"minimum_percent": 95.0, "tracked_files": ["relative.py"]}},
        tmp_path,
        coverage_xml,
    )

    assert issues == ["line coverage below 95.0%: relative.py (80.0%)"]


@pytest.mark.parametrize("branch_rate", [None, "nan", "inf", "-0.1", "1.1", "broken"])
def test_run_check_rejects_missing_or_invalid_branch_rates(
    tmp_path: Path,
    branch_rate: str | None,
) -> None:
    """Tracked files must carry finite Cobertura branch evidence."""
    attribute = "" if branch_rate is None else f' branch-rate="{branch_rate}"'
    coverage_xml = tmp_path / "coverage.xml"
    coverage_xml.write_text(
        f'<coverage><class filename="managed.py" line-rate="1"{attribute}/></coverage>',
        encoding="utf-8",
    )

    issues = run_check(
        {"coverage": {"tracked_files": ["managed.py"]}},
        tmp_path,
        coverage_xml,
    )

    assert len(issues) == 1
    assert issues[0].startswith("coverage xml invalid:")
    assert (
        compute_workspace_line_coverage(
            {"coverage": {"tracked_files": ["managed.py"]}},
            tmp_path,
            coverage_xml,
        )
        == 0.0
    )


def test_run_check_enforces_line_and_branch_rates_independently(tmp_path: Path) -> None:
    """A strong line score must not hide weak branch coverage."""
    coverage_xml = tmp_path / "coverage.xml"
    coverage_xml.write_text(
        '<coverage><class filename="managed.py" line-rate="1" branch-rate="0.5"/></coverage>',
        encoding="utf-8",
    )

    assert run_check(
        {"coverage": {"minimum_percent": 95, "tracked_files": ["managed.py"]}},
        tmp_path,
        coverage_xml,
    ) == ["branch coverage below 95.0%: managed.py (50.0%)"]


def test_run_check_accepts_cobertura_branchless_file_semantics(tmp_path: Path) -> None:
    """Coverage.py reports branchless files with branch-rate one."""
    coverage_xml = tmp_path / "coverage.xml"
    coverage_xml.write_text(
        '<coverage><class filename="managed.py" line-rate="1" branch-rate="1"/></coverage>',
        encoding="utf-8",
    )

    assert (
        run_check(
            {"coverage": {"minimum_percent": 95, "tracked_files": ["managed.py"]}},
            tmp_path,
            coverage_xml,
        )
        == []
    )