#!/usr/bin/env python3

from pathlib import Path
import fitz

BASE_DIR = Path(__file__).resolve().parents[1]
INPUT = BASE_DIR / "input" / "okular_test.pdf"
OUTPUT = BASE_DIR / "output" / "okular_test_updated.pdf"

OLD_TEXT = "TITLE TEXT HERE"
NEW_TEXT = "UPDATED TITLE TEXT\nLINE 2 UPDATED\nLINE 3 UPDATED"

doc = fitz.open(INPUT)

changed = 0

for page in doc:
    for annot in page.annots() or []:
        info = annot.info or {}
        content = info.get("content", "")

        if OLD_TEXT in content:
            info["content"] = NEW_TEXT
            annot.set_info(info)

            # FreeText annotations need appearance regenerated
            if annot.type[1] == "FreeText":
                annot.update()

            changed += 1

doc.save(OUTPUT, garbage=4, deflate=True)
doc.close()

print(f"Updated {changed} annotation(s)")
print(f"Wrote {OUTPUT}")