import os
from pathlib import Path

from flask import Flask, redirect, render_template, url_for
from flask_wtf import FlaskForm
from flask_wtf.csrf import CSRFProtect
from flask_wtf.file import FileAllowed, FileField, FileRequired
from werkzeug.utils import secure_filename
from wtforms import StringField
from wtforms.validators import DataRequired

app = Flask(__name__)
app.config["SECRET_KEY"] = "foo"
app.config["WTF_CSRF_SECRET_KEY"] = "bar"


CWD = Path().resolve()


class UploadForm(FlaskForm):
    pdf = FileField(validators=[FileAllowed(["pdf"], "PDFs only!"), FileRequired()])


@app.route("/")
def home():
    form = UploadForm()
    return render_template("index.html", form=form)


@app.route("/upload", methods=["POST"])
def upload():
    form = UploadForm()
    if form.validate_on_submit():
        f = form.pdf.data
        filename = secure_filename(f.filename)
        f.save(os.path.join(CWD, "pdfs", filename))
        return redirect(url_for("home"))
    return render_template("index.html", form=form)