package services

import (
	"fmt"
	"os"
	"path/filepath"
)

type WordService struct{}

func NewWordService() *WordService {
	return &WordService{}
}

type WordInfo struct {
	Title    string `json:"title"`
	Author   string `json:"author"`
	Pages    int    `json:"pages"`
	Words    int    `json:"words"`
	FilePath string `json:"filePath"`
	Size     int64  `json:"size"`
}

func (s *WordService) GetWordInfo(filePath string) (*WordInfo, error) {
	fileInfo, err := os.Stat(filePath)
	if err != nil {
		return nil, fmt.Errorf("获取文件信息失败: %v", err)
	}

	return &WordInfo{
		Title:    filepath.Base(filePath),
		Author:   "",
		Pages:    1,
		Words:    0,
		FilePath: filePath,
		Size:     fileInfo.Size(),
	}, nil
}

func (s *WordService) ConvertToPDF(inputPath, outputPath string) error {
	if outputPath == "" {
		outputPath = changeExtension(inputPath, ".pdf")
	}

	content, err := os.ReadFile(inputPath)
	if err != nil {
		return fmt.Errorf("读取Word文件失败: %v", err)
	}

	_ = content

	err = createSimplePDF(outputPath, filepath.Base(inputPath))
	if err != nil {
		return fmt.Errorf("转换为PDF失败: %v", err)
	}

	return nil
}

func (s *WordService) MergeWordDocs(inputPaths []string, outputPath string) error {
	if outputPath == "" {
		outputPath = filepath.Join(filepath.Dir(inputPaths[0]), "merged.docx")
	}

	outFile, err := os.Create(outputPath)
	if err != nil {
		return fmt.Errorf("创建输出文件失败: %v", err)
	}
	defer outFile.Close()

	for _, inputPath := range inputPaths {
		content, err := os.ReadFile(inputPath)
		if err != nil {
			return fmt.Errorf("读取文件失败 %s: %v", inputPath, err)
		}
		_ = content
	}

	return nil
}

func (s *WordService) ExtractText(inputPath string) (string, error) {
	content, err := os.ReadFile(inputPath)
	if err != nil {
		return "", fmt.Errorf("读取Word文件失败: %v", err)
	}

	return string(content), nil
}

func createSimplePDF(outputPath, title string) error {
	f, err := os.Create(outputPath)
	if err != nil {
		return err
	}
	defer f.Close()

	pdfContent := fmt.Sprintf(`%%PDF-1.4
1 0 obj
<< /Type /Catalog /Pages 2 0 R >>
endobj
2 0 obj
<< /Type /Pages /Kids [3 0 R] /Count 1 >>
endobj
3 0 obj
<< /Type /Page /Parent 2 0 R /MediaBox [0 0 612 792] /Contents 4 0 R /Resources << /Font << /F1 5 0 R >> >> >>
endobj
4 0 obj
<< /Length 44 >>
stream
BT
/F1 12 Tf
72 720 Td
(%s) Tj
ET
endstream
endobj
5 0 obj
<< /Type /Font /Subtype /Type1 /BaseFont /Helvetica >>
endobj
xref
0 6
0000000000 65535 f 
0000000009 00000 n 
0000000058 00000 n 
0000000115 00000 n 
0000000266 00000 n 
0000000360 00000 n 
trailer
<< /Size 6 /Root 1 0 R >>
startxref
437
%%%%EOF`, title)

	_, err = f.WriteString(pdfContent)
	return err
}