main.py

import datetime
import json
import random

from fastapi import FastAPI, HTTPException
from fastapi.responses import FileResponse

app = FastAPI()

# Currently the "/" has to be removed locally
images_dir = "/sources"


@app.get("/endpoints")
@app.get("/endpunkte")
async def get_endpoints():
    available_endpoints = read_endpoints()
    return {"message": f"Endpoints: {available_endpoints}"}


@app.get("/endpoints/{endpoint}")
@app.get("/endpunkte/{endpoint}")
async def get_image(endpoint: str):
    images = read_endpoint(endpoint).get("images")
    if images is None:
        raise HTTPException(status_code=404, detail="No images found")

    possible_images = list(filter((lambda image: image.get("file_name") is not None), images))

    importance_first_images = list(filter((lambda image: image.get("importance") == "first"), possible_images))
    if len(importance_first_images) > 0:
        return FileResponse(f"{images_dir}/{random.choice(importance_first_images)["file_name"]}")

    specific_date_and_time_range = list(
        filter((lambda image: is_today_in_specific_date_range(image) and is_now_in_time_range(image)), possible_images))
    if len(specific_date_and_time_range) > 0:
        return FileResponse(f"{images_dir}/{random.choice(specific_date_and_time_range)["file_name"]}")

    specific_date_range = list(filter((lambda image: is_today_in_specific_date_range(image)), possible_images))
    if len(specific_date_range) > 0:
        return FileResponse(f"{images_dir}/{random.choice(specific_date_range)["file_name"]}")
    possible_images = list(filter(lambda image: image.get("dateRange") is None, possible_images))

    general_date_and_time_range = list(
        filter((lambda image: is_today_in_general_date_range(image) and is_now_in_time_range(image)), possible_images))
    if len(general_date_and_time_range) > 0:
        return FileResponse(f"{images_dir}/{random.choice(general_date_and_time_range)["file_name"]}")

    general_date_range = list(filter((lambda image: is_today_in_general_date_range(image)), possible_images))
    if len(general_date_range) > 0:
        return FileResponse(f"{images_dir}/{random.choice(general_date_range)["file_name"]}")
    possible_images = list(filter(lambda image: image.get("annualDateRange") is None, possible_images))

    time_range = list(filter((lambda image: is_now_in_time_range(image)), possible_images))
    if len(time_range) > 0:
        return FileResponse(f"{images_dir}/{random.choice(time_range)["file_name"]}")
    possible_images = list(filter(lambda image: image.get("timeRange") is None, possible_images))

    if len(possible_images) == 0:
        raise HTTPException(status_code=404, detail="No valid images found")
    return FileResponse(f"{images_dir}/{random.choice(possible_images)["file_name"]}")


def read_endpoints():
    with open(f"{images_dir}/configuration.json") as config_reader:
        config = json.load(config_reader)
        endpoints = map((lambda endpoint: endpoint["name"]), config["endpoints"])
        return ", ".join(endpoints)


def read_endpoint(name: str):
    with open(f"{images_dir}/configuration.json") as config_reader:
        config = json.load(config_reader)
        return next(endpoint for endpoint in config["endpoints"] if endpoint["name"] == name)


def is_today_in_specific_date_range(image):
    date_range_object = image.get("dateRange")
    if date_range_object is None:
        return False
    current_date = datetime.datetime.now()
    specific_date_start = datetime.datetime.strptime(image.get("dateRange").get("from"), "%d.%m.%Y")
    specific_date_end = datetime.datetime.strptime(image.get("dateRange").get("to"), "%d.%m.%Y")
    return specific_date_start <= current_date <= specific_date_end


def is_today_in_general_date_range(image):
    date_range_object = image.get("annualDateRange")
    if date_range_object is None:
        return False
    current_date = datetime.datetime.now()
    date_start = datetime.datetime.strptime(image.get("annualDateRange").get("from"), "%d.%m.").replace(year=current_date.year)
    date_end = datetime.datetime.strptime(image.get("annualDateRange").get("to"), "%d.%m.").replace(year=current_date.year)
    if date_end < date_start:
        return date_start <= current_date <= date_end.replace(year=current_date.year+1) or date_start.replace(year=current_date.year-1) == date_end
    return date_start <= current_date <= date_end


def is_now_in_time_range(image):
    time_range_object = image.get("timeRange")
    if time_range_object is None:
        return False
    current_time = datetime.datetime.now().time()
    time_start = datetime.time(image.get("timeRange").get("from"), 0, 0)
    time_end = datetime.time(image.get("timeRange").get("to"), 0, 0)
    return time_start <= current_time <= time_end