"""Smoke test: run_page_pair_diff merges formatting findings into pair_diffs."""

import pytest

from document_mode.diff_engine import run_page_pair_diff


def _page(page_num, raw_text, spans, image_path='/tmp/dummy.png'):
    return {
        'page_num': page_num,
        'raw_text': raw_text,
        'spans': spans,
        'image_path': image_path,
        'fonts_used': [],
    }


def _span(text, bold=False):
    return {'text': text, 'bold': bold, 'italic': False, 'font': 'Helvetica',
            'size': 10.0, 'color': '#000000', 'bbox': (0, 10, 100, 22)}


def test_formatting_findings_surface_when_llm_returns_identical(tmp_path):
    # Create real dummy PNGs since _diff_one_pair tries to open them via PIL.
    from PIL import Image as PILImage
    img_path = tmp_path / "dummy.png"
    PILImage.new('RGB', (10, 10)).save(img_path)

    old_pages = [_page(
        1,
        "Theft of personal belongings if your car is left unattended unless windows are closed.",
        [_span("Theft of personal belongings if your car is left unattended", bold=True)],
        image_path=str(img_path),
    )]
    new_pages = [_page(
        1,
        "Theft of personal belongings if your car is left unattended unless windows are closed.",
        [_span("Theft of personal belongings if your car is left unattended", bold=False)],
        image_path=str(img_path),
    )]

    # LLM says: no differences. We expect the deterministic layer to override.
    def fake_llm(prompt, old_img, new_img, model_version=None):
        return (
            '{"differences_found": false, "added": [], "removed": [], '
            '"modified": [], "moved": [], "style_changes": [], '
            '"severity": "none", "summary": "Identical."}',
            {'prompt_tokens': 100, 'completion_tokens': 20, 'total_tokens': 120},
        )

    result = run_page_pair_diff(
        old_ingest={'pages': old_pages},
        new_ingest={'pages': new_pages},
        call_gemini_vision_fn=fake_llm,
    )

    pair_diff = result['pair_diffs']['1->1']['diff']
    assert pair_diff['differences_found'] is True
    assert pair_diff['severity'] == 'medium'
    assert len(pair_diff['formatting_changes']) == 1
    assert pair_diff['formatting_changes'][0]['attribute'] == 'bold'
    assert result['totals']['severity_counts']['medium'] >= 1