from typing import List, Tuple
import cv2
import numpy as np


class Preprocessing:
    """Preprocessing class.

    Parameters
    ----------
    clipLimit: float
        default = 5.0
    tileGridSize: Tuple[int, int]
        default = (15, 15)
    thresh1: int
        default = 0
    thresh2: int
        default = 255
    """

    def __init__(
        self,
        tileGridSize: Tuple[int, int] = (15, 15),
        clipLimit: float = 5.0,
        thresh1: int = 0,
        thresh2: int = 255,
    ) -> None:
        self.tileGridSize = tileGridSize
        self.clipLimit = clipLimit
        self.thresh1 = thresh1
        self.thresh2 = thresh2


    def gray(self, image: np.ndarray) -> np.ndarray:
        """Convert to GRAY for a given image.

        Parameters
        ----------
        image : np.ndarray
            image of chessboard

        Returns
        -------
        np.ndarray
            image of chessboard converted to GRAY
        """
        gray = cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
        return gray
    
    def clahe(self, image: np.ndarray) -> np.ndarray:
        """Apply Clahe to GRAY Shimage.

        Parameters
        ----------
        image : np.ndarray
            image of chessboard

        Returns
        -------
        np.ndarray
            image of chessboard converted to GRAY and applied CLAHE
        """
        clahe = cv2.createCLAHE(clipLimit = self.clipLimit, tileGridSize = self.tileGridSize)
        clahed = clahe.apply(self.gray(image))
        return clahed
    
    def threshold(self, image: np.ndarray) -> np.ndarray:
        """Apply Clahe to GRAY Shimage.

        Parameters
        ----------
        image : np.ndarray
            image of chessboard

        Returns
        -------
        np.ndarray
            image of chessboard converted to GRAY applied CLAHE and applied THRESHOLD
        """
        criteria = cv2.THRESH_BINARY + cv2.THRESH_OTSU+1
        ret, threshold  = cv2.threshold(self.clahe(image), self.thresh1, self.thresh2, criteria)
        return threshold