import os
import re
import requests
import urllib.parse

from bs4 import BeautifulSoup
from flask import flash, redirect, render_template, request, session
from functools import wraps


# Display apology message in case of an error
def apology(message, code=400):
    def escape(s):
        """
        Escape special characters.

        https://github.com/jacebrowning/memegen#special-characters
        """
        for old, new in [("-", "--"), (" ", "-"), ("_", "__"), ("?", "~q"),
                         ("%", "~p"), ("#", "~h"), ("/", "~s"), ("\"", "''")]:
            s = s.replace(old, new)
        return s
    flash("Apologies, something went wrong...")
    return render_template("apology.html", top=code, bottom=escape(message)), code


def deal_finder(item):
    """ Scraping best deals on ebay for the user-specified item """

    # https://www.networkinghowtos.com/howto/common-user-agent-list/
    header = {'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36'}
    # https://stackoverflow.com/questions/1549641/how-can-i-capitalize-the-first-letter-of-each-word-in-a-string
    item_spelling = " ".join(word[0].upper() + word[1:] for word in item.split())

    # Setup for displaying ebay results with the filter option "Price + Shipping: lowest first"
    search_term = item.replace(" ", "+")
    url = f"https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313&_nkw={search_term}&_sacat=0&_sop=15"
    webpage = requests.get(url, headers=header).text
    soup = BeautifulSoup(webpage, "lxml")

    offers = {}
    # getting a list of all divs that contain the info on each individual offer
    all_offers = soup.find_all("div", class_="s-item__info clearfix")
    for item in all_offers:
        # checking for matches in all caps too
        if item.find(text=re.compile(item_spelling)) != None and item.find(text=re.compile(item_spelling.upper())) == None:
            name = item.find(text=re.compile(item_spelling))
        elif item.find(text=re.compile(item_spelling)) == None and item.find(text=re.compile(item_spelling.upper())) != None:
            name = item.find(text=re.compile(item_spelling.upper()))
        else:
            continue

        # getting the price of each item
        if item.find("span", class_="s-item__price").string == None:
            continue
        price = item.find("span", class_="s-item__price").string.replace("$", "")

        # getting the link to the page of each item
        if item.a["href"] == None:
            continue
        link = item.a["href"]

        # the following code for "offers" & "best_deals" is based on: https://www.youtube.com/watch?v=zAEfWiC_KBU&t=1232s
        offers[name] = {"price": float(price.replace(",", "")), "link": link}

    best_deals = sorted(offers.items(), key=lambda x: x[1]["price"])
    return(best_deals)


def login_required(f):
    """
    Decorate routes to require login.

    https://flask.palletsprojects.com/en/1.1.x/patterns/viewdecorators/
    """
    @wraps(f)
    def decorated_function(*args, **kwargs):
        if session.get("user_id") is None:
            return redirect("/login")
        return f(*args, **kwargs)
    return decorated_function


def passw_requirements(password):
    """ Password requirements for registrating an account """

    pw_length = len(password)
    if pw_length in range(6,25) and password.isalpha() == False and password.isnumeric() == False:
        return "valid"
    else:
        return "invalid"


# Display a float as US-Dollar
def usd(value):
    return f"${value:,.2f}"