Blizzard
77 lines
1.5 KiB
Go
77 lines
1.5 KiB
Go
package parser
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import (
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"fmt"
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"os"
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"strings"
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"github.com/ledongthuc/pdf"
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)
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// PDFParser extracts plain text from PDF files using ledongthuc/pdf (open source).
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type PDFParser struct{}
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func (p *PDFParser) SupportedExtensions() []string {
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return []string{".pdf"}
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}
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func (p *PDFParser) ParseToMarkdown(path string) (string, error) {
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f, r, err := pdf.Open(path)
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if err != nil {
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return "", fmt.Errorf("open pdf: %w", err)
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}
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defer f.Close()
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var sb strings.Builder
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totalPages := r.NumPage()
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for i := 1; i <= totalPages; i++ {
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page := r.Page(i)
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if page.V.IsNull() {
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continue
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}
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text, err := page.GetPlainText(nil)
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if err != nil {
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continue
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}
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content := strings.TrimSpace(text)
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if content != "" {
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sb.WriteString(fmt.Sprintf("## Page %d\n\n%s\n\n", i, content))
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}
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}
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if sb.Len() == 0 {
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// Fallback: try reading entire content at once
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content, err := readPDFPlainText(path)
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if err == nil && content != "" {
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return content, nil
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}
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return "", fmt.Errorf("no text content extracted from PDF")
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}
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return sb.String(), nil
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}
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func readPDFPlainText(path string) (string, error) {
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f, err := os.Open(path)
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if err != nil {
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return "", err
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}
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defer f.Close()
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stat, _ := f.Stat()
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reader, err := pdf.NewReader(f, stat.Size())
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if err != nil {
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return "", err
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}
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var sb strings.Builder
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for i := 1; i <= reader.NumPage(); i++ {
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page := reader.Page(i)
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if page.V.IsNull() {
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continue
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}
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text, _ := page.GetPlainText(nil)
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sb.WriteString(text)
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}
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return sb.String(), nil
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}
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