// This program generates a minimal PDF with an annotation that references
// a non-existent object, which triggers a panic in pdfcpu split.
package main

import (
	"fmt"
	"os"
)

func main() {
	if len(os.Args) < 2 {
		fmt.Fprintf(os.Stderr, "usage: %s output.pdf\n", os.Args[0])
		os.Exit(1)
	}

	f, err := os.Create(os.Args[1])
	if err != nil {
		fmt.Fprintf(os.Stderr, "error: %v\n", err)
		os.Exit(1)
	}
	defer f.Close()

	offsets := make([]int64, 5) // objects 1-4, index 0 unused
	pos := int64(0)

	write := func(s string) {
		n, _ := f.WriteString(s)
		pos += int64(n)
	}

	// Header
	write("%PDF-1.4\n")

	// Object 1: Catalog
	offsets[1] = pos
	write("1 0 obj\n<< /Type /Catalog /Pages 2 0 R >>\nendobj\n")

	// Object 2: Pages
	offsets[2] = pos
	write("2 0 obj\n<< /Type /Pages /Kids [3 0 R] /Count 1 >>\nendobj\n")

	// Object 3: Page with annotation referencing non-existent object 99
	offsets[3] = pos
	write("3 0 obj\n<< /Type /Page /Parent 2 0 R /MediaBox [0 0 612 792] /Annots [99 0 R] >>\nendobj\n")

	// Object 4: a dummy so xref size is reasonable
	offsets[4] = pos
	write("4 0 obj\n<< /Length 0 >>\nstream\n\nendstream\nendobj\n")

	// Cross-reference table
	xrefPos := pos
	write("xref\n")
	write(fmt.Sprintf("0 %d\n", 5))
	write("0000000000 65535 f \n")
	for i := 1; i <= 4; i++ {
		write(fmt.Sprintf("%010d 00000 n \n", offsets[i]))
	}

	// Trailer
	write("trailer\n")
	write(fmt.Sprintf("<< /Size %d /Root 1 0 R >>\n", 5))
	write("startxref\n")
	write(fmt.Sprintf("%d\n", xrefPos))
	write("%%EOF\n")
}