import sys
import os

sys.path.append(os.path.join(os.path.dirname(__file__), 'gateway'))

try:
    import pdfengine
except ImportError as e:
    print(f"Failed to import pdfengine: {e}")
    sys.exit(1)

def main():
    corpus_dir = os.path.join(os.path.dirname(__file__), 'corpus', 'basic')
    source_pdf = os.path.join(corpus_dir, 'hello_world.pdf')
    dest_pdf = os.path.join(corpus_dir, 'hello_world_python.pdf')
    
    print(f"Testing StreamEditor on {source_pdf}")
    editor = pdfengine.StreamEditor(source_pdf)
    
    objects = editor.extract_text_objects(0)
    print(f"Extracted {len(objects)} text objects.")
    
    hello_idx = -1
    for i, obj in enumerate(objects):
        print(f"[{i}]: {obj['text']} (Font: {obj['fontName']} {obj['fontSize']}, Tm: {obj['tm']})")
        if obj['text'] == "Hello, world!":
            hello_idx = i
            
    if hello_idx == -1:
        print("Failed to find 'Hello, world!'")
        sys.exit(1)
        
    new_text = "Hello from Python pybind11!"
    print(f"\nReplacing object {hello_idx} with '{new_text}'...")
    
    success = editor.replace_text_object(0, hello_idx, new_text, dest_pdf)
    if not success:
        print("Failed to replace text object")
        sys.exit(1)
        
    print(f"Successfully saved modified PDF to {dest_pdf}")
    
    print("\nVerifying modification...")
    verify_editor = pdfengine.StreamEditor(dest_pdf)
    verify_objects = verify_editor.extract_text_objects(0)
    
    found = False
    for obj in verify_objects:
        if obj['text'] == new_text:
            found = True
            break
            
    if found:
        print("SUCCESS! Modified text was perfectly preserved.")
        if os.path.exists(dest_pdf):
            os.remove(dest_pdf)
    else:
        print("FAILURE! Modified text was not found in the output PDF.")
        sys.exit(1)

if __name__ == "__main__":
    main()