from app.pipeline.text_format import format_ocr_to_html, ocr_has_math


def test_empty_returns_empty_markup():
    assert str(format_ocr_to_html("")) == ""
    assert str(format_ocr_to_html(None)) == ""


def test_single_paragraph():
    out = str(format_ocr_to_html("Hello world"))
    assert out == "<p>Hello world</p>"


def test_multi_line_paragraph_uses_br():
    out = str(format_ocr_to_html("Line one\nLine two"))
    assert out == "<p>Line one<br>Line two</p>"


def test_blank_line_separates_paragraphs():
    out = str(format_ocr_to_html("First\n\nSecond"))
    assert out == "<p>First</p><p>Second</p>"


def test_html_special_chars_are_escaped():
    out = str(format_ocr_to_html("a < b & c > d"))
    assert "&lt;" in out and "&amp;" in out and "&gt;" in out


def test_bullet_list_unordered():
    text = "• First point\n• Second point\n• Third"
    out = str(format_ocr_to_html(text))
    assert out.startswith("<ul>")
    assert out.endswith("</ul>")
    assert out.count("<li>") == 3


def test_dash_bullets_recognized():
    text = "- alpha\n- beta"
    out = str(format_ocr_to_html(text))
    assert out == "<ul><li>alpha</li><li>beta</li></ul>"


def test_numbered_list_ordered():
    text = "1. step one\n2. step two\n3. step three"
    out = str(format_ocr_to_html(text))
    assert out.startswith("<ol>")
    assert out.count("<li>") == 3


def test_continuation_line_joins_previous_item():
    text = "• first item\n  with continuation\n• second"
    out = str(format_ocr_to_html(text))
    assert "first item with continuation" in out
    assert out.count("<li>") == 2


def test_equation_line_wrapped_in_mathjax():
    out = str(format_ocr_to_html("E = mc²"))
    assert "\\(" in out and "\\)" in out
    assert "^2" in out
    assert 'class="ocr-equation"' in out


def test_equation_normalizes_greek_and_operators():
    out = str(format_ocr_to_html("α × β = γ"))
    assert r"\alpha" in out
    assert r"\times" in out
    assert r"\beta" in out
    assert r"\gamma" in out


def test_long_prose_with_equals_is_not_treated_as_equation():
    text = (
        "If we set the value of x equal to zero, then the function evaluates "
        "to a constant of one as expected."
    )
    out = str(format_ocr_to_html(text))
    assert "\\(" not in out
    assert out.startswith("<p>")


def test_mixed_blocks():
    text = "Slide title\n\n• point one\n• point two\n\nx = 5"
    out = str(format_ocr_to_html(text))
    assert "<p>Slide title</p>" in out
    assert "<ul><li>point one</li><li>point two</li></ul>" in out
    assert "\\(x = 5\\)" in out


def test_ocr_has_math_detects_equation():
    assert ocr_has_math("Title\n\nE = mc²") is True
    assert ocr_has_math("∑ x_i") is True


def test_ocr_has_math_false_on_prose():
    assert ocr_has_math("Just a regular sentence about photosynthesis.") is False
    assert ocr_has_math("") is False
    assert ocr_has_math(None) is False