"""Surya OCR engine wrapper — transformer-based, handles typewritten and modern Latin handwriting."""

import logging

logger = logging.getLogger(__name__)

# Lazy-loaded at startup via load_models()
_recognition_model = None
_recognition_processor = None
_detection_model = None
_detection_processor = None


def load_models():
    """Eagerly load Surya models into memory. Called once at container startup."""
    global _recognition_model, _recognition_processor, _detection_model, _detection_processor

    logger.info("Loading Surya models...")

    from surya.model.detection.model import load_model as load_det_model
    from surya.model.detection.model import load_processor as load_det_processor
    from surya.model.recognition.model import load_model as load_rec_model
    from surya.model.recognition.processor import load_processor as load_rec_processor

    _detection_model = load_det_model()
    _detection_processor = load_det_processor()
    _recognition_model = load_rec_model()
    _recognition_processor = load_rec_processor()

    logger.info("Surya models loaded successfully")


def extract_blocks(images: list, language: str = "de") -> list[dict]:
    """Run Surya OCR on a list of PIL images (one per page).

    Returns a flat list of block dicts with pageNumber, x, y, width, height, text.
    Coordinates are normalized to [0, 1] relative to page dimensions.
    """
    from surya.detection import batch_text_detection
    from surya.recognition import batch_recognition

    all_blocks = []

    for page_idx, image in enumerate(images):
        page_w, page_h = image.size

        det_predictions = batch_text_detection([image], _detection_model, _detection_processor)
        rec_predictions = batch_recognition(
            [image], det_predictions, _recognition_model, _recognition_processor, [language]
        )

        for line in rec_predictions[0].text_lines:
            bbox = line.bbox  # [x1, y1, x2, y2] in pixel coordinates
            x1, y1, x2, y2 = bbox

            all_blocks.append({
                "pageNumber": page_idx,
                "x": x1 / page_w,
                "y": y1 / page_h,
                "width": (x2 - x1) / page_w,
                "height": (y2 - y1) / page_h,
                "polygon": None,
                "text": line.text,
            })

    return all_blocks