# image_import_worker.py
import time
import os
from sqlalchemy.exc import OperationalError
from app import create_app
from app.utils.image_importer import import_images_task

THUMBNAIL_FLAG = "/import/thumbnail.flag"
TRIGGER_FLAG = "/import/trigger.flag"
SOURCE_DIR = "/import"
DEST_DIR = "/images"
CHECK_INTERVAL = 10  # seconds

app = create_app()

from sqlalchemy.exc import OperationalError
import time

def monitor_and_import():
    with app.app_context():
        print("[Image Importer] Monitoring for trigger flag...")

        while True:
            if os.path.exists(TRIGGER_FLAG):
                print("[Image Importer] Trigger flag found. Starting import...")
                max_retries = 3
                attempt = 0

                while attempt < max_retries:
                    try:
                        result = import_images_task(SOURCE_DIR, DEST_DIR)
                        print(f"[Image Importer] {result}")
                        break  # Exit retry loop if successful
                    except OperationalError as e:
                        attempt += 1
                        print(f"[Image Importer] Database error during import (attempt {attempt}): {e}")
                        if attempt >= max_retries:
                            print("[Image Importer] Max retries reached. Import failed.")
                        else:
                            sleep_time = 2 ** attempt
                            print(f"[Image Importer] Retrying in {sleep_time} seconds...")
                            time.sleep(sleep_time)
                    except Exception as e:
                        print(f"[Image Importer] Unexpected error during import: {e}")
                        break
                    finally:
                        try:
                            os.remove(TRIGGER_FLAG)
                            print("[Image Importer] Trigger flag cleared.")
                        except Exception as e:
                            print(f"[Image Importer] Failed to remove trigger flag: {e}")

            if os.path.exists(THUMBNAIL_FLAG):
                print("[Image Importer] Thumbnail regeneration triggered.")
                max_retries = 3
                attempt = 0

                while attempt < max_retries:
                    try:
                        from app.models import ImageRecord
                        from app.utils.image_importer import generate_thumbnail

                        for img in ImageRecord.query.all():
                            try:
                                generate_thumbnail(img.filepath, overwrite=True)
                                print(f"[Thumbnail] Regenerated for {img.filename}")
                            except Exception as e:
                                print(f"[Thumbnail] Failed for {img.filename}: {e}")
                        break  # Success
                    except OperationalError as e:
                        attempt += 1
                        print(f"[Image Importer] Database error during thumbnail regen (attempt {attempt}): {e}")
                        if attempt >= max_retries:
                            print("[Image Importer] Max retries reached. Thumbnail regeneration failed.")
                        else:
                            sleep_time = 2 ** attempt
                            print(f"[Image Importer] Retrying in {sleep_time} seconds...")
                            time.sleep(sleep_time)
                    except Exception as e:
                        print(f"[Image Importer] Unexpected error during thumbnail regen: {e}")
                        break
                    finally:
                        try:
                            os.remove(THUMBNAIL_FLAG)
                            print("[Image Importer] Thumbnail flag cleared.")
                        except Exception as e:
                            print(f"[Image Importer] Failed to remove thumbnail flag: {e}")


if __name__ == '__main__':
    monitor_and_import()