"""
匯出模組單元測試

對應 TDD.md - UT-EXP-01: PDF 輸出完整性
驗證重點：
- 字型嵌入與 DPI 驗證
- 各種格式的輸出品質

Version: 1.0.0
DocID: TDD-UT-EXP-001
Related: SDD-API-003 (POST /export)
"""

import pytest
import os
from pathlib import Path
from datetime import datetime
from backend.schemas import ExportOptions, ExportFormat, Event, TimelineConfig
from backend.export import (
    FileNameSanitizer, ExportEngine, TimelineExporter,
    ExportError, create_metadata
)
from backend.renderer import TimelineRenderer

# 測試輸出目錄
TEST_OUTPUT_DIR = Path(__file__).parent.parent / "temp_output"


@pytest.fixture
def setup_output_dir():
    """建立測試輸出目錄"""
    TEST_OUTPUT_DIR.mkdir(parents=True, exist_ok=True)
    yield TEST_OUTPUT_DIR
    # 清理測試檔案
    if TEST_OUTPUT_DIR.exists():
        for file in TEST_OUTPUT_DIR.glob("*"):
            try:
                file.unlink()
            except:
                pass


@pytest.fixture
def sample_figure():
    """建立範例 Plotly 圖表"""
    events = [
        Event(id="1", title="Event 1", start=datetime(2024, 1, 1)),
        Event(id="2", title="Event 2", start=datetime(2024, 1, 5)),
        Event(id="3", title="Event 3", start=datetime(2024, 1, 10))
    ]
    renderer = TimelineRenderer()
    result = renderer.render(events, TimelineConfig())

    import plotly.graph_objects as go
    fig = go.Figure(data=result.data.get('data', []), layout=result.layout)
    return fig


class TestFileNameSanitizer:
    """檔名淨化器測試"""

    def test_sanitize_normal_name(self):
        """測試正常檔名"""
        result = FileNameSanitizer.sanitize("my_timeline_2024")
        assert result == "my_timeline_2024"

    def test_sanitize_illegal_chars(self):
        """測試移除非法字元"""
        result = FileNameSanitizer.sanitize("my<timeline>2024:test")
        assert '<' not in result
        assert '>' not in result
        assert ':' not in result

    def test_sanitize_reserved_name(self):
        """測試保留字處理"""
        result = FileNameSanitizer.sanitize("CON")
        assert result == "_CON"

    def test_sanitize_long_name(self):
        """測試過長檔名"""
        long_name = "a" * 300
        result = FileNameSanitizer.sanitize(long_name)
        assert len(result) <= FileNameSanitizer.MAX_LENGTH

    def test_sanitize_empty_name(self):
        """測試空檔名"""
        result = FileNameSanitizer.sanitize("")
        assert result == "timeline"

    def test_sanitize_trailing_spaces(self):
        """測試移除尾部空格和點"""
        result = FileNameSanitizer.sanitize("test.  ")
        assert not result.endswith('.')
        assert not result.endswith(' ')


class TestExportEngine:
    """匯出引擎測試"""

    def test_export_engine_initialization(self):
        """測試匯出引擎初始化"""
        engine = ExportEngine()
        assert engine is not None
        assert engine.filename_sanitizer is not None

    def test_export_pdf_basic(self, sample_figure, setup_output_dir):
        """測試基本 PDF 匯出"""
        engine = ExportEngine()
        output_path = setup_output_dir / "test.pdf"
        options = ExportOptions(fmt=ExportFormat.PDF, dpi=300)

        result = engine.export(sample_figure, output_path, options)

        assert result.exists()
        assert result.suffix == '.pdf'
        assert result.stat().st_size > 0

    def test_export_png_basic(self, sample_figure, setup_output_dir):
        """測試基本 PNG 匯出"""
        engine = ExportEngine()
        output_path = setup_output_dir / "test.png"
        options = ExportOptions(fmt=ExportFormat.PNG, dpi=300)

        result = engine.export(sample_figure, output_path, options)

        assert result.exists()
        assert result.suffix == '.png'
        assert result.stat().st_size > 0

    def test_export_svg_basic(self, sample_figure, setup_output_dir):
        """測試基本 SVG 匯出"""
        engine = ExportEngine()
        output_path = setup_output_dir / "test.svg"
        options = ExportOptions(fmt=ExportFormat.SVG)

        result = engine.export(sample_figure, output_path, options)

        assert result.exists()
        assert result.suffix == '.svg'
        assert result.stat().st_size > 0

    def test_export_png_with_transparency(self, sample_figure, setup_output_dir):
        """測試 PNG 透明背景"""
        engine = ExportEngine()
        output_path = setup_output_dir / "transparent.png"
        options = ExportOptions(
            fmt=ExportFormat.PNG,
            transparent_background=True
        )

        result = engine.export(sample_figure, output_path, options)

        assert result.exists()
        assert result.suffix == '.png'

    def test_export_custom_dimensions(self, sample_figure, setup_output_dir):
        """測試自訂尺寸"""
        engine = ExportEngine()
        output_path = setup_output_dir / "custom_size.png"
        options = ExportOptions(
            fmt=ExportFormat.PNG,
            width=1280,
            height=720
        )

        result = engine.export(sample_figure, output_path, options)

        assert result.exists()

    def test_export_high_dpi(self, sample_figure, setup_output_dir):
        """測試高 DPI 匯出"""
        engine = ExportEngine()
        output_path = setup_output_dir / "high_dpi.png"
        options = ExportOptions(fmt=ExportFormat.PNG, dpi=600)

        result = engine.export(sample_figure, output_path, options)

        assert result.exists()
        # 高 DPI 檔案應該較大
        assert result.stat().st_size > 0

    def test_export_creates_directory(self, sample_figure, setup_output_dir):
        """測試自動建立目錄"""
        engine = ExportEngine()
        nested_path = setup_output_dir / "subdir" / "test.pdf"
        options = ExportOptions(fmt=ExportFormat.PDF)

        result = engine.export(sample_figure, nested_path, options)

        assert result.exists()
        assert result.parent.exists()

    def test_export_filename_sanitization(self, sample_figure, setup_output_dir):
        """測試檔名淨化"""
        engine = ExportEngine()
        output_path = setup_output_dir / "test<invalid>name.pdf"
        options = ExportOptions(fmt=ExportFormat.PDF)

        result = engine.export(sample_figure, output_path, options)

        assert result.exists()
        assert '<' not in result.name
        assert '>' not in result.name


class TestTimelineExporter:
    """時間軸匯出器測試"""

    def test_exporter_initialization(self):
        """測試匯出器初始化"""
        exporter = TimelineExporter()
        assert exporter is not None
        assert exporter.export_engine is not None

    def test_export_from_plotly_json(self, setup_output_dir):
        """測試從 Plotly JSON 匯出"""
        # 先渲染出 Plotly JSON
        events = [Event(id="1", title="Test", start=datetime(2024, 1, 1))]
        renderer = TimelineRenderer()
        result = renderer.render(events, TimelineConfig())

        exporter = TimelineExporter()
        output_path = setup_output_dir / "from_json.pdf"
        options = ExportOptions(fmt=ExportFormat.PDF)

        exported = exporter.export_from_plotly_json(
            result.data,
            result.layout,
            output_path,
            options
        )

        assert exported.exists()
        assert exported.suffix == '.pdf'

    def test_export_to_directory_with_default_name(self, setup_output_dir):
        """測試匯出至目錄並自動命名"""
        events = [Event(id="1", title="Test", start=datetime(2024, 1, 1))]
        renderer = TimelineRenderer()
        result = renderer.render(events, TimelineConfig())

        exporter = TimelineExporter()
        options = ExportOptions(fmt=ExportFormat.PNG)

        exported = exporter.export_from_plotly_json(
            result.data,
            result.layout,
            setup_output_dir,
            options,
            filename_prefix="my_timeline"
        )

        assert exported.exists()
        assert "my_timeline" in exported.name
        assert exported.suffix == '.png'

    def test_generate_default_filename(self):
        """測試生成預設檔名"""
        exporter = TimelineExporter()

        filename = exporter.generate_default_filename(ExportFormat.PDF)

        assert "timeline_" in filename
        assert filename.endswith('.pdf')

    def test_generate_default_filename_format(self):
        """測試預設檔名格式"""
        exporter = TimelineExporter()

        for fmt in [ExportFormat.PDF, ExportFormat.PNG, ExportFormat.SVG]:
            filename = exporter.generate_default_filename(fmt)
            assert filename.endswith(f'.{fmt.value}')
            assert filename.startswith('timeline_')


class TestExportErrorHandling:
    """匯出錯誤處理測試"""

    def test_export_to_readonly_location(self, sample_figure, tmp_path):
        """測試寫入唯讀位置"""
        # 建立唯讀目錄（在 Windows 上這個測試可能需要調整）
        readonly_dir = tmp_path / "readonly"
        readonly_dir.mkdir()

        # 在某些系統上可能無法真正設定唯讀，所以這個測試可能會跳過
        # 這裡主要測試錯誤處理機制存在
        engine = ExportEngine()
        output_path = readonly_dir / "test.pdf"
        options = ExportOptions(fmt=ExportFormat.PDF)

        try:
            # 嘗試匯出
            result = engine.export(sample_figure, output_path, options)
            # 如果成功，清理檔案
            if result.exists():
                result.unlink()
        except ExportError:
            # 預期的錯誤
            pass

    def test_export_empty_timeline(self, setup_output_dir):
        """測試匯出空白時間軸"""
        # 建立空白時間軸
        renderer = TimelineRenderer()
        result = renderer.render([], TimelineConfig())

        exporter = TimelineExporter()
        output_path = setup_output_dir / "empty.pdf"
        options = ExportOptions(fmt=ExportFormat.PDF)

        # 應該不會崩潰，能生成空白圖檔
        exported = exporter.export_from_plotly_json(
            result.data,
            result.layout,
            output_path,
            options
        )

        assert exported.exists()


class TestExportMetadata:
    """匯出元資料測試"""

    def test_create_metadata_default(self):
        """測試建立預設元資料"""
        metadata = create_metadata()

        assert 'Title' in metadata
        assert 'Creator' in metadata
        assert 'Producer' in metadata
        assert 'CreationDate' in metadata
        assert 'TimeLine Designer' in metadata['Title']

    def test_create_metadata_custom_title(self):
        """測試自訂標題元資料"""
        metadata = create_metadata(title="My Project Timeline")

        assert metadata['Title'] == "My Project Timeline"
        assert 'TimeLine Designer' in metadata['Creator']


class TestExportFileFormats:
    """匯出檔案格式測試"""

    def test_pdf_file_format(self, sample_figure, setup_output_dir):
        """測試 PDF 檔案格式正確"""
        engine = ExportEngine()
        output_path = setup_output_dir / "test.pdf"
        options = ExportOptions(fmt=ExportFormat.PDF)

        result = engine.export(sample_figure, output_path, options)

        # 檢查檔案開頭是否為 PDF 標記
        with open(result, 'rb') as f:
            header = f.read(5)
            assert header == b'%PDF-'

    def test_png_file_format(self, sample_figure, setup_output_dir):
        """測試 PNG 檔案格式正確"""
        engine = ExportEngine()
        output_path = setup_output_dir / "test.png"
        options = ExportOptions(fmt=ExportFormat.PNG)

        result = engine.export(sample_figure, output_path, options)

        # 檢查 PNG 檔案簽名
        with open(result, 'rb') as f:
            header = f.read(8)
            assert header == b'\x89PNG\r\n\x1a\n'

    def test_svg_file_format(self, sample_figure, setup_output_dir):
        """測試 SVG 檔案格式正確"""
        engine = ExportEngine()
        output_path = setup_output_dir / "test.svg"
        options = ExportOptions(fmt=ExportFormat.SVG)

        result = engine.export(sample_figure, output_path, options)

        # 檢查 SVG 內容
        with open(result, 'r', encoding='utf-8') as f:
            content = f.read()
            assert '<svg' in content or '<?xml' in content


class TestExportIntegration:
    """匯出整合測試"""

    def test_full_workflow_pdf(self, setup_output_dir):
        """測試完整 PDF 匯出流程"""
        # 1. 建立事件
        events = [
            Event(id="1", title="專案啟動", start=datetime(2024, 1, 1)),
            Event(id="2", title="需求分析", start=datetime(2024, 1, 5)),
            Event(id="3", title="開發階段", start=datetime(2024, 1, 10))
        ]

        # 2. 渲染時間軸
        renderer = TimelineRenderer()
        config = TimelineConfig(direction='horizontal', theme='modern')
        result = renderer.render(events, config)

        # 3. 匯出為 PDF
        exporter = TimelineExporter()
        options = ExportOptions(fmt=ExportFormat.PDF, dpi=300)
        exported = exporter.export_from_plotly_json(
            result.data,
            result.layout,
            setup_output_dir / "workflow_test.pdf",
            options
        )

        # 4. 驗證結果
        assert exported.exists()
        assert exported.stat().st_size > 1000  # 至少 1KB

    def test_full_workflow_all_formats(self, setup_output_dir):
        """測試所有格式的完整流程"""
        events = [Event(id="1", title="Test", start=datetime(2024, 1, 1))]

        renderer = TimelineRenderer()
        result = renderer.render(events, TimelineConfig())

        exporter = TimelineExporter()

        for fmt in [ExportFormat.PDF, ExportFormat.PNG, ExportFormat.SVG]:
            options = ExportOptions(fmt=fmt)
            exported = exporter.export_from_plotly_json(
                result.data,
                result.layout,
                setup_output_dir / f"all_formats.{fmt.value}",
                options
            )

            assert exported.exists()
            assert exported.suffix == f'.{fmt.value}'


if __name__ == "__main__":
    pytest.main([__file__, "-v"])