import datetime
import uuid
import asyncio
from pathlib import Path

from fastapi import FastAPI, Depends, UploadFile, Form, File, HTTPException, BackgroundTasks
from starlette.responses import HTMLResponse, FileResponse
from starlette.staticfiles import StaticFiles

from sqlalchemy import select, update
from sqlalchemy.ext.asyncio.session import AsyncSession

import settings
from utils import delete_expire_files, storage, get_code
from database import get_session, Codes, init_models
from depends import admin_required, IPRateLimit

app = FastAPI(debug=settings.DEBUG)

DATA_ROOT = Path(settings.DATA_ROOT)
if not DATA_ROOT.exists():
    DATA_ROOT.mkdir(parents=True)

STATIC_URL = settings.STATIC_URL
app.mount(STATIC_URL, StaticFiles(directory=DATA_ROOT), name="static")


@app.on_event('startup')
async def startup():
    await init_models()
    asyncio.create_task(delete_expire_files())


index_html = open('templates/index.html', 'r', encoding='utf-8').read() \
    .replace('{{title}}', settings.TITLE) \
    .replace('{{description}}', settings.DESCRIPTION) \
    .replace('{{keywords}}', settings.KEYWORDS)
admin_html = open('templates/admin.html', 'r', encoding='utf-8').read() \
    .replace('{{title}}', settings.TITLE) \
    .replace('{{description}}', settings.DESCRIPTION) \
    .replace('{{keywords}}', settings.KEYWORDS)

ip_limit = IPRateLimit()


@app.get(f'/{settings.ADMIN_ADDRESS}')
async def admin():
    return HTMLResponse(admin_html)


@app.post(f'/{settings.ADMIN_ADDRESS}', dependencies=[Depends(admin_required)])
async def admin_post(s: AsyncSession = Depends(get_session)):
    query = select(Codes)
    codes = (await s.execute(query)).scalars().all()
    return {'detail': '查询成功', 'data': codes}


@app.delete(f'/{settings.ADMIN_ADDRESS}', dependencies=[Depends(admin_required)])
async def admin_delete(code: str, s: AsyncSession = Depends(get_session)):
    query = select(Codes).where(Codes.code == code)
    file = (await s.execute(query)).scalars().first()
    if file:
        if file.type != 'text':
            await storage.delete_file(file.text)
        await s.delete(file)
        await s.commit()
    return {'detail': '删除成功'}


@app.get('/')
async def index():
    return HTMLResponse(index_html)


@app.get('/select')
async def get_file(code: str, s: AsyncSession = Depends(get_session)):
    query = select(Codes).where(Codes.code == code)
    info = (await s.execute(query)).scalars().first()
    if not info:
        raise HTTPException(status_code=404, detail="口令不存在")
    if info.type == 'text':
        return {'detail': '查询成功', 'data': info.text}
    else:
        filepath = await storage.get_filepath(info.text)
        return FileResponse(filepath, filename=info.name)


@app.post('/')
async def index(code: str, ip: str = Depends(ip_limit), s: AsyncSession = Depends(get_session)):
    query = select(Codes).where(Codes.code == code)
    info = (await s.execute(query)).scalars().first()
    if not info:
        error_count = settings.ERROR_COUNT - ip_limit.add_ip(ip)
        raise HTTPException(status_code=404, detail=f"取件码错误，错误{error_count}次将被禁止10分钟")
    if info.exp_time < datetime.datetime.now() or info.count == 0:
        if info.type != "text":
            await storage.delete_file(info.text)
        await s.delete(info)
        await s.commit()
        raise HTTPException(status_code=404, detail="取件码已过期，请联系寄件人")
    await s.execute(update(Codes).where(Codes.id == info.id).values(count=info.count - 1))
    await s.commit()
    if info.type != 'text':
        info.text = f'/select?code={code}'
    return {
        'detail': '取件成功，请点击"取"查看',
        'data': {'type': info.type, 'text': info.text, 'name': info.name, 'code': info.code}
    }


@app.post('/share')
async def share(background_tasks: BackgroundTasks, text: str = Form(default=None), style: str = Form(default='2'),
                value: int = Form(default=1), file: UploadFile = File(default=None),
                s: AsyncSession = Depends(get_session)):
    code = await get_code(s)
    if style == '2':
        if value > 7:
            raise HTTPException(status_code=400, detail="最大有效天数为7天")
        exp_time = datetime.datetime.now() + datetime.timedelta(days=value)
        exp_count = -1
    elif style == '1':
        if value < 1:
            raise HTTPException(status_code=400, detail="最小有效次数为1次")
        exp_time = datetime.datetime.now() + datetime.timedelta(days=1)
        exp_count = value
    else:
        exp_time = datetime.datetime.now() + datetime.timedelta(days=1)
        exp_count = -1
    key = uuid.uuid4().hex
    if file:
        size = await storage.get_size(file)
        if size > settings.FILE_SIZE_LIMIT:
            raise HTTPException(status_code=400, detail="文件过大")
        _text, _type, name = await storage.get_text(file, key), file.content_type, file.filename
        background_tasks.add_task(storage.save_file, file, _text)
    else:
        size, _text, _type, name = len(text), text, 'text', '文本分享'
    info = Codes(code=code, text=_text, size=size, type=_type, name=name, count=exp_count, exp_time=exp_time, key=key)
    s.add(info)
    await s.commit()
    return {
        'detail': '分享成功，请点击取件码按钮查看上传列表',
        'data': {'code': code, 'key': key, 'name': name, 'text': _text}
    }


if __name__ == '__main__':
    import uvicorn

    uvicorn.run('main:app', host='0.0.0.0', port=settings.PORT, debug=settings.DEBUG)