# Import FastAPI Libs
from pydantic import BaseModel

# Import Other Common Libs
import json
import base64
import os

import requests

# ------------------------------------------------
# Define constants
# ------------------------------------------------
c_ret_code_success = 0
c_ret_code_error = 1

credential_file = '/home/oracle/python/apex/credential/credential.json'
# env = 'aliyun_ecs'
env = 'ctyun_ecs'

# ------------------------------------------------
# Define OCR Request Service Request and Response
# ------------------------------------------------
class ocr_req_basemodel(BaseModel):
    ocr_tool: str # Q: Qcloud, LP: Local PaddleOCR
    dir: str
    file_name: str

class ocr_res_basemodel(BaseModel):
    result: int
    result_message: str
    detected_text: list


# ------------------------------------------------
# Get credentials
# ------------------------------------------------
def get_credentials(file: str, env: str) -> tuple:

    try:
        # Open and read the JSON file
        with open(file, "r") as credential_file:
            data = json.load(credential_file)

        # Access data from the JSON
        base_url = data['paddle'][env]['base_url']
        client_id = data['paddle'][env]['client_id']
        client_secret = data['paddle'][env]['client_secret']

        return base_url, client_id, client_secret

    except Exception as e:

        print(e)
        return None, None, None

# ------------------------------------------------
# Function of OCR request to Paddle OCR
# ------------------------------------------------
def get_detected_text(ocr_req: ocr_req_basemodel) -> tuple:

    ret_code = c_ret_code_success
    err_msg = ""

    # ------------------------------------------------
    # Get URL and credential
    # ------------------------------------------------
    base_url, client_id, client_secret = get_credentials(credential_file, env);

    if base_url == None or client_id == None or client_secret == None:

        ret_code = c_ret_code_error
        err_msg = "Failed to get credential from file [" + credential_file + "] and env [" + env + "]"

        ocr_res = ocr_res_basemodel(
            result          = ret_code,
            result_message  = err_msg,
            detected_text   = []
        )

        return ocr_res

    # ------------------------------------------------
    # Get Token
    # ------------------------------------------------
    url = base_url + "/token"
    access_token = ""

    headers = {
        "Authorization": "Bearer " + access_token,
        "Content-type": "application/x-www-form-urlencoded"
    }

    req_body = "grant_type=&username={0}&password={1}".format(client_id, client_secret)

    try:
        response = requests.post(
            url = url,
            headers = headers,
            data = req_body,
            verify = False)
        
        response.raise_for_status
        response_dict = response.json()
        print(response.text)

        access_token = response_dict["access_token"]
        print(access_token)

    except requests.exceptions.HTTPError as httpError:
        print("httpError")
        print(httpError)
        ret_code = c_ret_code_error
        err_msg = "HTTP Error: Failed to get access token: " + str(httpError)

        ocr_res = ocr_res_basemodel(
            result          = ret_code,
            result_message  = err_msg,
            detected_text   = []
        )

        return ocr_res

    except Exception as err:
        print("err")
        print(err)
        ret_code = c_ret_code_error
        err_msg = "Unexpected Error: Failed to get access token: " + str(err)

        ocr_res = ocr_res_basemodel(
            result          = ret_code,
            result_message  = err_msg,
            detected_text   = []
        )

        return ocr_res


    # ------------------------------------------------
    # Get Detected Text
    # ------------------------------------------------
    url = base_url + "/paddleocr/read-image"

    # 打开文件
    with open(os.path.normpath(os.path.join(ocr_req.dir, ocr_req.file_name)), "rb") as image_file:
        encoded_string = base64.b64encode(image_file.read()).decode('utf-8')
        # print(encoded_string)

    headers = {
        "accept": "application/json",
        "Authorization": "Bearer " + access_token,
        "Content-Type": "application/json"
    }

    data = {
        "image_b64_string": encoded_string
    }

    json_data = json.dumps(data)

    try:
        response = requests.post(
            url = url,
            headers = headers,
            data = json_data,
            verify = False)

        response.raise_for_status
        response_dict = response.json()

        ocr_res = ocr_res_basemodel(
            result          = ret_code,
            result_message  = err_msg,
            detected_text   = response_dict
        )

        return ocr_res

    except requests.exceptions.HTTPError as httpError:
        ret_code = c_ret_code_error
        err_msg = "HTTP Error: Failed to get detected text: " + str(httpError)

        ocr_res = ocr_res_basemodel(
            result          = ret_code,
            result_message  = err_msg,
            detected_text   = []
        )

        return ocr_res

    except Exception as err:
        ret_code = c_ret_code_error
        if (response.text):
            err_msg = "Unexpected Error: Failed to get detected text: " + str(err) + ", " + response.text
        else:
            err_msg = "Unexpected Error: Failed to get detected text: " + str(err)

        ocr_res = ocr_res_basemodel(
            result          = ret_code,
            result_message  = err_msg,
            detected_text   = []
        )

        return ocr_res