from fastapi import FastAPI, Query
import csv
import os
from threading import Thread
import time
import pandas as pd
import tempfile
from google.cloud import storage

app = FastAPI()

data_location = None
reading_thread = None
stop_reading = False
counter = 0

gcs_bucket_name = "ow-stu-us-ce1-ai-platform"

# process of getting credentials
def get_credentials():
    creds_json_str = os.getenv("BOB") # get json credentials stored as a string
    if creds_json_str is None:
        raise ValueError("GOOGLE_APPLICATION_CREDENTIALS_JSON not found in environment")

    # create a temporary file
    with tempfile.NamedTemporaryFile(mode="w+", delete=False, suffix=".json") as temp:
        temp.write(creds_json_str) # write in json format
        temp_filename = temp.name 

    return temp_filename
    
# pass
os.environ["GOOGLE_APPLICATION_CREDENTIALS"]= get_credentials()

# Ensure the GCS bucket exists
gcs_client = storage.Client()
gcs_bucket = gcs_client.bucket(gcs_bucket_name)

# File path in GCS bucket
gcs_file_path = "deepak_6593/db.csv"


def read_csv(location="chennai"):
    global stop_reading
    global data_location
    global counter
    blob = gcs_bucket.blob(gcs_file_path)
    while not stop_reading:
        file_path = f"https://storage.googleapis.com/dev.openweaver.com/demo/ai/{location}.csv"
        data = pd.read_csv(file_path)
        csv_data = data[0:counter].to_csv(index=False).encode('utf-8')
        blob.upload_from_string(csv_data, content_type='text/csv')
        time.sleep(5)
        counter += 1


def start_reading(location):
    global reading_thread
    reading_thread = Thread(target=read_csv, args=(location,))
    reading_thread.start()

def stop_reading_thread():
    global stop_reading
    global reading_thread
    stop_reading = True
    if reading_thread is not None:
        reading_thread.join()

@app.get("/update_location/")
async def update_location(location: str = Query("tambaram")):
    global reading_thread
    global stop_reading

    if location not in ["tambaram", "velachery"]:
        return {"error": "Invalid location"}

    if reading_thread is not None and reading_thread.is_alive():
        stop_reading_thread()

    stop_reading = False
    start_reading(location)

    return {"message": f"Location updated to {location}"}

# if __name__ == "__main__":
#     import uvicorn

#     uvicorn.run(app, host="0.0.0.0", port=8080)