"""
Tests for file parser tool
Author: @mangubee
Date: 2026-01-02

Tests cover:
- PDF parsing
- Excel parsing
- Word document parsing
- Text/CSV parsing
- Retry logic
- Error handling
"""

import pytest
from pathlib import Path
from unittest.mock import Mock, patch, MagicMock
from src.tools.file_parser import (
    parse_pdf,
    parse_excel,
    parse_word,
    parse_text,
    parse_file,
)

# ============================================================================
# Test Fixtures
# ============================================================================

FIXTURES_DIR = Path(__file__).parent / "fixtures"


@pytest.fixture
def sample_text_file():
    """Path to sample text file"""
    return str(FIXTURES_DIR / "sample.txt")


@pytest.fixture
def sample_csv_file():
    """Path to sample CSV file"""
    return str(FIXTURES_DIR / "sample.csv")


@pytest.fixture
def sample_excel_file():
    """Path to sample Excel file"""
    return str(FIXTURES_DIR / "sample.xlsx")


@pytest.fixture
def sample_word_file():
    """Path to sample Word file"""
    return str(FIXTURES_DIR / "sample.docx")


@pytest.fixture
def mock_pdf_reader():
    """Mock PyPDF2 PdfReader"""
    mock_page_1 = Mock()
    mock_page_1.extract_text.return_value = "Test PDF page 1 content"

    mock_page_2 = Mock()
    mock_page_2.extract_text.return_value = "Test PDF page 2 content"

    mock_reader = Mock()
    mock_reader.pages = [mock_page_1, mock_page_2]

    return mock_reader


# ============================================================================
# PDF Parser Tests
# ============================================================================

def test_parse_pdf_success(mock_pdf_reader):
    """Test successful PDF parsing"""
    with patch('PyPDF2.PdfReader') as mock_reader_class:
        with patch('src.tools.file_parser.Path') as mock_path_class:
            # Mock file exists
            mock_path = Mock()
            mock_path.exists.return_value = True
            mock_path_class.return_value = mock_path

            # Mock PdfReader
            mock_reader_class.return_value = mock_pdf_reader

            result = parse_pdf("test.pdf")

            assert result["file_type"] == "PDF"
            assert result["pages"] == 2
            assert "page 1 content" in result["content"].lower()
            assert "page 2 content" in result["content"].lower()


def test_parse_pdf_file_not_found():
    """Test PDF parsing with missing file"""
    with patch('src.tools.file_parser.Path') as mock_path_class:
        mock_path = Mock()
        mock_path.exists.return_value = False
        mock_path_class.return_value = mock_path

        with pytest.raises(FileNotFoundError):
            parse_pdf("nonexistent.pdf")


def test_parse_pdf_io_error_retry():
    """Test PDF parsing with IO error triggers retry"""
    with patch('PyPDF2.PdfReader') as mock_reader_class:
        with patch('src.tools.file_parser.Path') as mock_path_class:
            # Mock file exists
            mock_path = Mock()
            mock_path.exists.return_value = True
            mock_path_class.return_value = mock_path

            # Mock IO error
            mock_reader_class.side_effect = IOError("Disk error")

            with pytest.raises(IOError):
                parse_pdf("test.pdf")

            # Verify retry happened (should be called MAX_RETRIES times)
            assert mock_reader_class.call_count == 3


# ============================================================================
# Excel Parser Tests
# ============================================================================

def test_parse_excel_success(sample_excel_file):
    """Test successful Excel parsing with real file"""
    result = parse_excel(sample_excel_file)

    assert result["file_type"] == "Excel"
    assert len(result["sheets"]) == 2
    assert "Data" in result["sheets"]
    assert "Summary" in result["sheets"]
    assert "Apple" in result["content"]
    assert "Banana" in result["content"]


def test_parse_excel_file_not_found():
    """Test Excel parsing with missing file"""
    with pytest.raises(FileNotFoundError):
        parse_excel("nonexistent.xlsx")


def test_parse_excel_io_error_retry():
    """Test Excel parsing with IO error triggers retry"""
    with patch('openpyxl.load_workbook') as mock_load:
        with patch('src.tools.file_parser.Path') as mock_path_class:
            # Mock file exists
            mock_path = Mock()
            mock_path.exists.return_value = True
            mock_path_class.return_value = mock_path

            # Mock IO error
            mock_load.side_effect = IOError("Disk error")

            with pytest.raises(IOError):
                parse_excel("test.xlsx")

            # Verify retry happened
            assert mock_load.call_count == 3


# ============================================================================
# Word Document Parser Tests
# ============================================================================

def test_parse_word_success(sample_word_file):
    """Test successful Word document parsing with real file"""
    result = parse_word(sample_word_file)

    assert result["file_type"] == "Word"
    assert result["paragraphs"] > 0
    assert "Test Word Document" in result["content"]
    assert "first paragraph" in result["content"]


def test_parse_word_file_not_found():
    """Test Word parsing with missing file"""
    with pytest.raises(FileNotFoundError):
        parse_word("nonexistent.docx")


def test_parse_word_io_error_retry():
    """Test Word parsing with IO error triggers retry"""
    with patch('docx.Document') as mock_doc_class:
        with patch('src.tools.file_parser.Path') as mock_path_class:
            # Mock file exists
            mock_path = Mock()
            mock_path.exists.return_value = True
            mock_path_class.return_value = mock_path

            # Mock IO error
            mock_doc_class.side_effect = IOError("Disk error")

            with pytest.raises(IOError):
                parse_word("test.docx")

            # Verify retry happened
            assert mock_doc_class.call_count == 3


# ============================================================================
# Text/CSV Parser Tests
# ============================================================================

def test_parse_text_success(sample_text_file):
    """Test successful text file parsing with real file"""
    result = parse_text(sample_text_file)

    assert result["file_type"] == "Text"
    assert result["lines"] > 0
    assert "test text file" in result["content"].lower()


def test_parse_csv_success(sample_csv_file):
    """Test successful CSV file parsing with real file"""
    result = parse_text(sample_csv_file)

    assert result["file_type"] == "CSV"
    assert result["lines"] > 0
    assert "Name,Age,City" in result["content"]
    assert "Alice" in result["content"]


def test_parse_text_file_not_found():
    """Test text parsing with missing file"""
    with pytest.raises(FileNotFoundError):
        parse_text("nonexistent.txt")


def test_parse_text_io_error_retry():
    """Test text parsing with IO error triggers retry"""
    with patch('builtins.open') as mock_open:
        with patch('src.tools.file_parser.Path') as mock_path_class:
            # Mock file exists
            mock_path = Mock()
            mock_path.exists.return_value = True
            mock_path.suffix = '.txt'
            mock_path_class.return_value = mock_path

            # Mock IO error
            mock_open.side_effect = IOError("Disk error")

            with pytest.raises(IOError):
                parse_text("test.txt")

            # Verify retry happened
            assert mock_open.call_count == 3


# ============================================================================
# Unified Parser Tests
# ============================================================================

def test_parse_file_pdf():
    """Test unified parser dispatches to PDF parser"""
    with patch('src.tools.file_parser.parse_pdf') as mock_parse_pdf:
        mock_parse_pdf.return_value = {"file_type": "PDF"}

        result = parse_file("test.pdf")

        assert result["file_type"] == "PDF"
        mock_parse_pdf.assert_called_once()


def test_parse_file_excel():
    """Test unified parser dispatches to Excel parser"""
    with patch('src.tools.file_parser.parse_excel') as mock_parse_excel:
        mock_parse_excel.return_value = {"file_type": "Excel"}

        result = parse_file("test.xlsx")

        assert result["file_type"] == "Excel"
        mock_parse_excel.assert_called_once()


def test_parse_file_word():
    """Test unified parser dispatches to Word parser"""
    with patch('src.tools.file_parser.parse_word') as mock_parse_word:
        mock_parse_word.return_value = {"file_type": "Word"}

        result = parse_file("test.docx")

        assert result["file_type"] == "Word"
        mock_parse_word.assert_called_once()


def test_parse_file_text():
    """Test unified parser dispatches to text parser"""
    with patch('src.tools.file_parser.parse_text') as mock_parse_text:
        mock_parse_text.return_value = {"file_type": "Text"}

        result = parse_file("test.txt")

        assert result["file_type"] == "Text"
        mock_parse_text.assert_called_once()


def test_parse_file_unsupported_extension():
    """Test unified parser rejects unsupported file type"""
    with pytest.raises(ValueError, match="Unsupported file type"):
        parse_file("test.mp4")


def test_parse_file_xls_extension():
    """Test unified parser handles .xls extension"""
    with patch('src.tools.file_parser.parse_excel') as mock_parse_excel:
        mock_parse_excel.return_value = {"file_type": "Excel"}

        result = parse_file("test.xls")

        assert result["file_type"] == "Excel"
        mock_parse_excel.assert_called_once()