import pytest
from unittest.mock import AsyncMock, MagicMock

from app.core.exceptions import LLMParseError, StorageError, UnsupportedFileTypeError
from app.models.text_models import TextExtractRequest


SAMPLE_TRIPLES_JSON = '''[
  {
    "subject": "变压器",
    "predicate": "额定电压",
    "object": "110kV",
    "source_snippet": "该变压器额定电压为110kV",
    "source_offset": {"start": 0, "end": 12}
  }
]'''


@pytest.fixture
def req_txt():
    return TextExtractRequest(file_path="text/test.txt", file_name="test.txt")


@pytest.fixture
def req_pdf():
    return TextExtractRequest(file_path="text/test.pdf", file_name="report.pdf")


@pytest.fixture
def req_docx():
    return TextExtractRequest(file_path="text/test.docx", file_name="doc.docx")


@pytest.fixture
def llm(mock_llm):
    mock_llm.chat = AsyncMock(return_value=SAMPLE_TRIPLES_JSON)
    return mock_llm


@pytest.mark.asyncio
async def test_txt_extraction_returns_triples(llm, mock_storage):
    mock_storage.download_bytes = AsyncMock(return_value=b"test content")
    from app.services.text_service import extract_triples
    req = TextExtractRequest(file_path="text/test.txt", file_name="test.txt")
    result = await extract_triples(req, llm, mock_storage)
    assert len(result.items) == 1
    assert result.items[0].subject == "变压器"
    assert result.items[0].predicate == "额定电压"
    assert result.items[0].object == "110kV"
    assert result.items[0].source_offset.start == 0
    assert result.items[0].source_offset.end == 12


@pytest.mark.asyncio
async def test_pdf_extraction(llm, mock_storage, tmp_path):
    import pdfplumber, io
    # We mock download_bytes to return a minimal PDF-like response
    # and mock pdfplumber.open to return pages with text
    mock_storage.download_bytes = AsyncMock(return_value=b"%PDF fake")

    with pytest.MonkeyPatch().context() as mp:
        mock_page = MagicMock()
        mock_page.extract_text.return_value = "PDF content here"
        mock_pdf = MagicMock()
        mock_pdf.__enter__ = lambda s: s
        mock_pdf.__exit__ = MagicMock(return_value=False)
        mock_pdf.pages = [mock_page]
        mp.setattr("pdfplumber.open", lambda f: mock_pdf)

        from app.services import text_service
        import importlib
        importlib.reload(text_service)
        req = TextExtractRequest(file_path="text/test.pdf", file_name="doc.pdf")
        result = await text_service.extract_triples(req, llm, mock_storage)
    assert len(result.items) == 1


@pytest.mark.asyncio
async def test_docx_extraction(llm, mock_storage):
    mock_storage.download_bytes = AsyncMock(return_value=b"PK fake docx bytes")

    with pytest.MonkeyPatch().context() as mp:
        mock_para = MagicMock()
        mock_para.text = "Word paragraph content"
        mock_doc = MagicMock()
        mock_doc.paragraphs = [mock_para]
        mp.setattr("docx.Document", lambda f: mock_doc)

        from app.services import text_service
        import importlib
        importlib.reload(text_service)
        req = TextExtractRequest(file_path="text/test.docx", file_name="doc.docx")
        result = await text_service.extract_triples(req, llm, mock_storage)
    assert len(result.items) == 1


@pytest.mark.asyncio
async def test_unsupported_format_raises_error(llm, mock_storage):
    mock_storage.download_bytes = AsyncMock(return_value=b"data")
    from app.services.text_service import extract_triples
    req = TextExtractRequest(file_path="text/test.xlsx", file_name="data.xlsx")
    with pytest.raises(UnsupportedFileTypeError):
        await extract_triples(req, llm, mock_storage)


@pytest.mark.asyncio
async def test_storage_error_propagates(llm, mock_storage):
    mock_storage.download_bytes = AsyncMock(side_effect=StorageError("not found"))
    from app.services.text_service import extract_triples
    req = TextExtractRequest(file_path="text/test.txt", file_name="test.txt")
    with pytest.raises(StorageError):
        await extract_triples(req, llm, mock_storage)


@pytest.mark.asyncio
async def test_llm_parse_error_propagates(mock_llm, mock_storage):
    mock_storage.download_bytes = AsyncMock(return_value=b"content")
    mock_llm.chat = AsyncMock(return_value="not json {{")
    from app.services.text_service import extract_triples
    req = TextExtractRequest(file_path="text/test.txt", file_name="test.txt")
    with pytest.raises(LLMParseError):
        await extract_triples(req, mock_llm, mock_storage)