from fastapi import FastAPI
from fastapi.staticfiles import StaticFiles
from fastapi.responses import FileResponse


from time import time
from statistics import mean

from modules.details import rand_details
from modules.inference import generate_image

app = FastAPI()

app.mount("/static", StaticFiles(directory="static"), name="static")


tasks = {}


def get_place_in_queue(task_id):

    pending_tasks = list(task for task in tasks.values()
                         if task["status"] == "pending")

    try:
        return pending_tasks.index(task_id) + 1
    except:
        return 0


def calculate_eta(task_id):
    total_durations = list(task["completed_at"] - task["created_at"]
                           for task in tasks.values() if "completed_at" in task)

    place = tasks[task_id]["initial_place_in_queue"] or 1

    if len(total_durations):
        return mean(total_durations) * place
    else:
        return 40 * place


@app.get('/')
def index():
    return FileResponse(path="static/index.html", media_type="text/html")


@app.get('/task/create')
def create_task(prompt: str = "покемон"):
    created_at = time()

    task_id = f"{str(created_at)}_{prompt}"

    tasks[task_id] = {
        "task_id": task_id,
        "created_at": created_at,
        "prompt": prompt,
        "initial_place_in_queue": get_place_in_queue(task_id),
        "status": "pending",
        "poll_count": 0,
    }

    print("Place in queue: ", get_place_in_queue(task_id))
    print("ETA: ", calculate_eta(task_id))

    return tasks[task_id]


@app.get('/task/queue')
def queue_task(task_id: str):
    try:
        tasks[task_id]["value"] = generate_image(tasks[task_id]["prompt"])
    except Exception as ex:
        tasks[task_id]["status"] = "failed"
        tasks[task_id]["error"] = repr(ex)
    else:
        tasks[task_id]["status"] = "completed"
    finally:
        tasks[task_id]["completed_at"] = time()

    return tasks[task_id]


@app.get('/task/poll')
def poll_task(task_id: str):
    pending_tasks = []
    completed_durations = []

    for task in tasks.values():
        if task["status"] == "pending":
            pending_tasks.append(task["task_id"])
        elif task["status"] == "completed":
            completed_durations.append(
                task["completed_at"] - task["created_at"])

    try:
        place_in_queue = pending_tasks.index(task_id) + 1
    except:
        place_in_queue = 0

    if (len(completed_durations)):
        eta = sum(completed_durations) / \
            len(completed_durations) * (place_in_queue or 1)
    else:
        eta = 40 * (place_in_queue or 1)

    tasks[task_id]["place_in_queue"] = place_in_queue
    tasks[task_id]["eta"] = round(eta, 1)
    tasks[task_id]["poll_count"] += 1

    return tasks[task_id]


# @app.route('/details')
@app.get('/details')
async def generate_details():
    return rand_details()


@app.get('/duck/quack')
async def test(query: str = "quack"):
    print(query)
    return {"duck": query}


@app.get('/test')
async def test(query: str = "test"):
    print(query)
    return {"query": query}