import os
import random
import threading

from flask import render_template, Blueprint, Response, after_this_request, request, send_file, stream_with_context

from ebayavgprice import UPLOAD_FOLDER, RESULTS_FOLDER, FILE_NAME_PREFIX
from ebayavgprice.forms import FileUploadForm
from ebayavgprice.functions import EbayAvgPrice

app_bp = Blueprint("app_bp", __name__, template_folder="templates")

exporting_threads = {}


@app_bp.route("/", methods=["GET", "POST"])
def index():
    global exporting_threads
    form = FileUploadForm()

    if form.validate_on_submit():
        document = form.document.data
        has_headers = form.has_headers.data
        delete_after_upload = form.delete_after_upload.data
        delete_after_download = form.delete_after_download.data
        filename = str(random.randint(100000, 999999)) + "_" + document.filename
        upload_location = os.path.join(UPLOAD_FOLDER, filename)
        document.save(upload_location)
        user_thread = EbayAvgPrice(upload_location, has_headers)
        thread_id = len(exporting_threads) + 1
        exporting_threads[thread_id] = user_thread
        threading.Thread(target=user_thread.get_avg_price).start()
        msg = f"{document.filename} uploaded successfully"
        if delete_after_upload:
            os.remove(upload_location)

        return render_template("index.html",
                               delete=delete_after_download,
                               form=form,
                               filename=FILE_NAME_PREFIX + filename,
                               message=msg,
                               thread_id=thread_id,
                               track=True)

    return render_template("index.html", form=form, errors=form.errors)


@app_bp.route("/progress/<int:thread_id>")
def progress(thread_id):
    global exporting_threads

    @after_this_request
    def delete_thread(response):
        del exporting_threads[thread_id]
        return response

    return Response(exporting_threads[thread_id].get_progress(), mimetype='text/event-stream')


@app_bp.route("/download")
def download():
    file = request.args.get("file")
    delete = bool(request.args.get("delete"))

    if delete:
        @after_this_request
        def remove_file(response):
            os.remove(os.path.join(RESULTS_FOLDER, file))
            return response

    response = send_file(os.path.join(RESULTS_FOLDER, file), attachment_filename=file, as_attachment=True)
    response.headers["x-filename"] = file
    response.headers["Access-Control-Expose-Headers"] = 'x-filename'
    return response