# -*- coding: utf-8 -*-
# ------------------------------------------------------------------------------
# File Name: paddleocr_service.py
# Original Author: Clark Lin
# Email: clark_lin@outlook.com
#
# Change History
# Version   Date        By          Description
# 0.01      2024-04-24  Clark Lin   Initial version
# 
# Main features summary:
# - Implementation of PaddleOCR Invocation
# 
# Copyright Information:
# Copyright © 2024 Oasis
# Licensed TBD
# ------------------------------------------------------------------------------
from paddleocr import PaddleOCR
from io import BytesIO
from PIL import Image
import numpy as np
import base64
import fastapi_security_util
from pydantic import BaseModel
from jose import JWTError, jwt
from fastapi import HTTPException, status

# Import your custom logging manager
import os
import logging
from common.script.logging_manager import LoggingManager

# Initialize logging manager
curr_module = os.path.basename(__file__)
# lm = LoggingManager()
lm = LoggingManager.get_instance()


# ------------------------------------------------
# Model Definition
# ------------------------------------------------
class RawImage(BaseModel):
    image_b64_string: str


# ------------------------------------------------
# Sub Function - Verify Access Token
# ------------------------------------------------
def verify_token(token: str):

    secret_key, client_db = fastapi_security_util.get_credentials(fastapi_security_util.credential_file)

    try:
        payload = jwt.decode(token, secret_key, algorithms=[fastapi_security_util.algorithm])
        username: str = payload.get("sub")
        if username is None:
            return False
        return True
    except JWTError:
        lm.log(logging.ERROR, curr_module, 'JWTError: ', str(JWTError))
        return False


# ------------------------------------------------
# Sub Function - Read Image
# ------------------------------------------------
def read_image(token: str, image: RawImage):

    if not verify_token(token = token):
        raise HTTPException(
            status_code = status.HTTP_401_UNAUTHORIZED,
            detail = "Authentication Failed",
            headers={"WWW-Authenticate": "Bearer"},
        )

    l_text = []
    try:
        ocr = PaddleOCR(use_angle_cls=True, lang="ch") 

        # Convert the base64 string to a byte array
        image_data = base64.b64decode(image.image_b64_string)

        # 将解码后的二进制数据转换为 PIL Image 对象
        image_buffer = BytesIO(image_data)
        pil_image = Image.open(image_buffer)
        
        # 将 PIL Image 对象转换为 numpy 数组
        image_array = np.array(pil_image)
        
        # 初始化 PaddleOCR 并加载图像数组
        result = ocr.ocr(image_array, det=True, rec=True)

        for idx in range(len(result)):
            res = result[idx]
            for line in res:
                l_text.append(line[1][0])
        
        lm.log(logging.INFO, curr_module, 'read_image completed with normal')
    
    except Exception as e:
        lm.log(logging.ERROR, curr_module, 'Exception: ', str(e))

    return l_text