homepage.py

from main import app
from flask import Flask,redirect,url_for,render_template,abort,request,abort,make_response,session,g,flash
import sqlite3
from werkzeug.utils import secure_filename
import os

@app.route('/add', methods=['POST'])
def add_product_to_cart():
    cursor = None

    _quantity = int(request.form['quantity']) #when the add to cart button is pressed it returns the quantity and the unique ISBN that are saved in _quantity and _code
    _code = str(request.form['ISBN'])

    all_total_price = 0
    all_total_quantity = 0
    
    if _quantity and _code and request.method == 'POST':
        #code for creating shopping cart is based on 5001CEM (2021), Teaching Materials
        con = sqlite3.connect('prime.db')
        cur = con.cursor();
        cur.execute("SELECT * FROM stock WHERE ISBN=?;", [_code])
        row = cur.fetchone()
        #session['book'] is a dictionary of dictionaries, which means that each isbn number inside it correlates to some data about a book, which we will later use when creating a shopping cart
        itemArray = { str(row[3]) : {'name' : row [0], 'code' : row[3], 'quantity' : _quantity, 'price' : row[6], 'image' : row[5], 'total_price' : _quantity * row[6]}}
        print('itemArray is', itemArray)
        
        code = str(row[3])
        session.modified = True
            
        if 'book' in session:
            print('in session')
            if code in session['book']: #if user already added to basket at least one copy of this book
                for key, value in session['book'].items(): #search trough the session untill we find the book that needs updating
                    if code == key: 
                        old_quantity = session['book'][key]['quantity']
                        total_quantity = old_quantity + _quantity
                        if total_quantity > row[8]: # if the quantity asked from the add to cart button is more than the stock we use a flash
                            flash('You cannot add more books than there are in stock same item') 
                            cur.close()
                            con.close()   
                            return redirect(url_for('homepage'))
                        session['book'][key]['quantity'] = total_quantity
                        session['book'][key]['total_price'] = total_quantity * row[6]
            else: #if the item is not the first item added and is different from the one allready added we merge the 2 dictionaries
                session['book'] = array_merge(session['book'], itemArray)            
            for key, value in session['book'].items(): # we update the all_total_quantity and all_total_price
                individual_quantity = int(session['book'][key]['quantity'])
                individual_price = float(session['book'][key]['total_price'])
                if individual_quantity > row[8] : # if the quantity asked from the add to cart button is more than the stock we use a flash
                    flash('You cannot add more books than there are in stock not same item') 
                    con.close()   
                    return redirect(url_for('homepage'))
                all_total_quantity = all_total_quantity + individual_quantity
                all_total_price = all_total_price + individual_price
        else: # if there is no book in the cart we add the first item and update all_total_price and all_total_quantity
            session['book'] = itemArray #add the fist instance of a book to the session
            all_total_quantity = all_total_quantity + _quantity
            all_total_price = all_total_price + _quantity * row[6]  
            if all_total_quantity > row[8] : # if the quantity asked from the add to cart button is more than the stock we use a flash
                flash('You cannot add more books than there are in stock first item')
                cur.close()
                con.close()   
                return redirect(url_for('homepage'))
            
            #update the sessions
        session['all_total_quantity'] = all_total_quantity 
        session['all_total_price'] = all_total_price

        cur.close()
        con.close()       
        return redirect(url_for('homepage'))
    #end of adapted code
    
@app.route('/homepage', methods=['GET', 'POST'])
def homepage():
    if request.method == 'POST':
        if request.form['Submit'] == 'STOCK LEVEL':
            return redirect(url_for('stock_level'))
        elif request.form['Submit'] == 'LOGOUT':
            session.clear() #clears everything from our session
            return redirect(url_for('login'))
        elif request.form['Submit'] == 'CART':
            return redirect(url_for('shopping_cart')) #this function is located in shopping_cart.py file
    else:
        con = sqlite3.connect('prime.db') # in order to show the books on our page, we first have to get them from our database
        cur = con.cursor()
        cur.execute("SELECT * FROM stock") #select everything from books table
        rows = cur.fetchall() #put it inside a variable
        return render_template('homepage.html',page=url_for('homepage'),rows=rows) #render a html file


@app.route('/delete/<string:code>')
def delete_product(code):
    #the code for deleting an item from the shopping cart is based on 5001CEM (2021), Teaching Materials
	try:
		all_total_price = 0
		all_total_quantity = 0
		session.modified = True
		
		for item in session['book'].items():#iterates trough session['book'] to find the item that needs to be deleted
			if item[0] == str(code):		
				session['book'].pop(item[0], None)
                #checks if there is still an item in the cart
				if 'book' in session:
                    #updates all_total_quantity and all_total_price
					for key, value in session['book'].items():
						individual_quantity = int(session['book'][key]['quantity'])
						individual_price = float(session['book'][key]['price'])
						all_total_quantity +=  individual_quantity
						all_total_price +=  individual_price
				break
		
		if all_total_quantity == 0: #clear session if all_total_quantity = 0
			session.clear()
		else:
			session['all_total_quantity'] = all_total_quantity #updates all_total_quantity
			session['all_total_price'] = all_total_price #updates all_total_price
		return redirect(url_for('shopping_cart'))
	except Exception as e:
		print(e)
    #end of adapted code

def array_merge( first_array , second_array ):
     #code for creating shopping cart is based on 5001CEM (2021), Teaching Materials
	if isinstance( first_array , list ) and isinstance( second_array , list ):
		return first_array + second_array
	elif isinstance( first_array , dict ) and isinstance( second_array , dict ):
		return dict( list( first_array.items() ) + list( second_array.items() ) )
	elif isinstance( first_array , set ) and isinstance( second_array , set ):
		return first_array.union( second_array )
	return False		
    #end of borrowed code

    
'''do_payment is not working yet'''
def do_payment():
    con = sqlite3.connect('prime.db') 
    cur = con.cursor()
    cur.execute("SELECT * FROM stock") #select everything from books table
    rows = cur.fetchall() #put it inside a variable
    return render_template('homepage.html',page=url_for('homepage'),rows=rows) #render a html file

    #for key, value in session['book'].items():
        #not implemented yet


if __name__ == "__main__":
    app.run()