from fastapi import Depends, FastAPI, HTTPException, Query, Body
from contextlib import asynccontextmanager
import asyncio
from statistics import median

from db import *
from call2api import check_user_token, user_in_db, transfer_coins, get_stats, create_invoice, delete_invoice, \
	get_invoice


#------------------------------------------------------------
# INIT
#------------------------------------------------------------
@asynccontextmanager
async def lifespan(app: FastAPI):
	init_engine()
	await create_db_and_tables()
	yield

app = FastAPI(lifespan=lifespan)

CONFIG = asyncio.run(read())
SYSTEM_API_TOKEN = CONFIG['system_api_token']
#------------------------- END ------------------------------


#------------------------------------------------------------
# APIs (main code)
#------------------------------------------------------------
async def token_check(username, user_token):
	return await check_user_token(SYSTEM_API_TOKEN, username, user_token)

@app.post('/api/register_user_token/')
async def register_user_token_api(
	token: str = Body(),
	user_token: str = Body(),
	session: AsyncSession = Depends(get_session)
):
	if token != SYSTEM_API_TOKEN:
		raise HTTPException(status_code=401, detail='Invalid token')
	user_token_db = await user_token_in_db_func(session, user_token)
	if user_token_db:
		raise HTTPException(status_code=409, detail='Token already exist')
	new_user_token = UserToken(token=user_token)
	try:
		session.add(new_user_token)
		await session.commit()
		await session.refresh(new_user_token)
		return 'OK'
	except Exception as e:
		await session.rollback()
		raise HTTPException(status_code=500, detail=str(e))

@app.post('/api/unregister_user_token/')
async def unregister_user_token_api(
	token: str = Body(),
	user_token: str = Body(),
	session: AsyncSession = Depends(get_session)
):
	if token != SYSTEM_API_TOKEN:
		raise HTTPException(status_code=401, detail='Invalid token')
	user_token_db = await user_token_in_db_func(session, user_token)
	if not user_token_db:
		raise HTTPException(status_code=409, detail='Token not exist')
	try:
		await session.delete(user_token_db)
		await session.commit()
		return 'OK'
	except Exception as e:
		await session.rollback()
		raise HTTPException(status_code=500, detail=str(e))

@app.post('/api/get_user_token_info/')
async def get_user_token_info_api(
	username: str | None = Body(None),
	user_token: str = Body(),
	session: AsyncSession = Depends(get_session)
):
	if not token_check(username, user_token):
		raise HTTPException(status_code=401, detail='Invalid username or token')
	user_token_db = await user_token_in_db_func(session, user_token)
	if not user_token_db:
		raise HTTPException(status_code=409, detail='Token not exist')
	# Force data retrieval (DB can not load it properly, because it "lazy")
	issue_date = await session.run_sync(lambda sess: user_token_db.issue_date)
	logs = await session.run_sync(lambda sess: user_token_db.logs)
	return {'issue_date': issue_date, 'logs': logs}

@app.post('/api/user_in_db/')
async def user_in_db_api(
	username: str | None = Body(None),
	user_token: str = Body(),
	session: AsyncSession = Depends(get_session)
):
	if not token_check(username, user_token):
		raise HTTPException(status_code=401, detail='Invalid username or token')
	return await user_in_db(token=SYSTEM_API_TOKEN, username=username)

@app.post('/api/transfer_coins/')
async def transfer_coins_api(
	username: str = Body(),
	user_token: str = Body(),
	dst_username: str = Body(),
	amount: float = Body(),
	session: AsyncSession = Depends(get_session)
):
	if not token_check(username, user_token):
		raise HTTPException(status_code=401, detail='Invalid username or token')
	return await transfer_coins(token=SYSTEM_API_TOKEN, src_username=username
								, dst_username=dst_username, amount=amount)

@app.post('/api/get_stats/')
async def get_stats_api(
	username: str = Body(),
	user_token: str = Body()
):
	if not token_check(username, user_token):
		raise HTTPException(status_code=401, detail='Invalid username or token')
	return await get_stats(token=SYSTEM_API_TOKEN)

@app.post('/api/create_invoice/')
async def create_invoice_api(
	username: str = Body(),
	user_token: str = Body(),
	amount: float | None = Body(None)
):
	if not token_check(username, user_token):
		raise HTTPException(status_code=401, detail='Invalid username or token')
	return await create_invoice(token=SYSTEM_API_TOKEN, dst_username=username, amount=amount)

@app.post('/api/delete_invoice/')
async def delete_invoice_api(
	username: str = Body(),
	user_token: str = Body(),
	id: str = Body()
):
	if not token_check(username, user_token):
		raise HTTPException(status_code=401, detail='Invalid username or token')
	return await delete_invoice(token=SYSTEM_API_TOKEN, id=id)

@app.post('/api/get_invoice/')
async def get_invoice_api(
	username: str = Body(),
	user_token: str = Body(),
	id: str = Body()
):
	if not token_check(username, user_token):
		raise HTTPException(status_code=401, detail='Invalid username or token')
	return await get_invoice(token=SYSTEM_API_TOKEN, id=id)

#------------------------- END ------------------------------


#------------------------------------------------------------
# START
#------------------------------------------------------------
if __name__ == '__main__':
	import uvicorn
	uvicorn.run(app, host='0.0.0.0', port=8010)
#------------------------- END ------------------------------