"""Tests for structural drift detection (FR-700)."""

from __future__ import annotations

from markidocx.differ import compare


class TestCompare:
    def test_identical_text_no_drift(self) -> None:
        md = "# Heading\n\nParagraph.\n\n- item one\n- item two"
        report = compare(md, md)
        assert not report.has_drift
        assert report.preserved
        assert not report.broken
        assert not report.degraded

    def test_missing_heading_detected(self) -> None:
        original = "# Heading One\n\n## Heading Two\n\nText."
        reimported = "# Heading One\n\nText."
        report = compare(original, reimported)
        assert report.has_drift
        assert any("Heading Two" in b for b in report.broken)

    def test_missing_list_item_detected(self) -> None:
        original = "- alpha\n- beta\n- gamma"
        reimported = "- alpha\n- gamma"
        report = compare(original, reimported)
        assert report.has_drift
        assert any("beta" in b for b in report.broken)

    def test_preserved_links_tracked(self) -> None:
        md = "See [example](https://example.com) for details."
        report = compare(md, md)
        assert any("link" in p for p in report.preserved)

    def test_empty_strings_no_drift(self) -> None:
        report = compare("", "")
        assert not report.has_drift

    def test_table_presence_checked(self) -> None:
        original = "| A | B |\n|---|---|\n| 1 | 2 |"
        reimported = "No table here."
        report = compare(original, reimported)
        assert report.has_drift