added login cookie, added change pwd screen

auth.py

@@ -1,14 +1,82 @@
-from flask import Blueprint, render_template, request, redirect, url_for, flash
+from flask import Blueprint, render_template, request, redirect, url_for, flash, make_response
 from flask_login import login_user, logout_user, login_required, current_user
 from models import db
 from models import User
 from log import Log
+import pickle
+from cryptography.fernet import Fernet
+import datetime
+
 
 auth_bp = Blueprint("auth", __name__)
 
+# =====================================================
+# SECRET KEY (only your program has this)
+# =====================================================
+# Generate once using: Fernet.generate_key()
+_SECRET_KEY = b'YFK7QCyTzhyLO4vqrnRxvDAI5uu8mXEYrInEjbRoQgs='
+
+fernet = Fernet(_SECRET_KEY)
+
+# =====================================================
+# ENCRYPT
+# =====================================================
+def encrypt_object(obj) -> bytes:
+    """
+    Encrypt any Python object and return encrypted bytes.
+    """
+    serialized = pickle.dumps(obj)
+    encrypted = fernet.encrypt(serialized)
+    return encrypted
+
+# =====================================================
+# DECRYPT
+# =====================================================
+def decrypt_object(encrypted_data: bytes):
+    """
+    Decrypt bytes back into the original Python object.
+    """
+    decrypted = fernet.decrypt(encrypted_data)
+    obj = pickle.loads(decrypted)
+    return obj
+
+def create_cookie(userid):
+    cookie_data = {
+        "user": userid,
+        "datetime": datetime.datetime.now()
+    }
+    return encrypt_object(cookie_data).decode('utf-8')
+
+def is_cookie_ok_to_autologin(cookie_content):
+    user = 0
+    autologin = False
+    try:
+        cookie_data = decrypt_object(cookie_content)
+        user = cookie_data["user"]
+        dt = cookie_data["datetime"]
+        lastweek = datetime.datetime.now() - datetime.timedelta(days=7)
+        autologin = dt > lastweek
+    except:
+        Log.info("Cookie error")
+    if autologin:
+        return user
+    return 0
+
+
+
+
 #. @auth_bp.route("/", methods=["GET", "POST"])
 @auth_bp.route("/login", methods=["GET", "POST"])
 def login():
+    username = request.cookies.get('username')
+
+    userid = is_cookie_ok_to_autologin(username)
+    if userid>0:
+        user = User.query.filter_by(id=userid).first()
+        if user and user.is_approved:
+            login_user(user)
+            return redirect(url_for("lists.home"))
+    
     if request.method == "POST":
         user = User.query.filter_by(name=request.form["name"]).first()
         if user and user.check_password(request.form["password"]):
@@ -18,7 +86,12 @@ def login():
             return redirect(url_for("lists.home"))
         flash("Invalid credentials")
         Log.info(f"Authorization failure for user '{request.form["name"]}' ")
-    return render_template("login.html")
+
+    
+    resp = make_response(render_template("login.html"))
+    resp.set_cookie('username', '')
+    return resp
+    
 
 @auth_bp.route("/register", methods=["GET", "POST"])
 def register():
@@ -34,5 +107,27 @@ def register():
 @login_required
 def logout():
     logout_user()
-    return redirect(url_for("auth.login"))
+    resp = make_response(redirect(url_for("auth.login")))
+    resp.set_cookie('username', '')
+    return resp
 
+
+@auth_bp.route("/change_pwd", methods=["GET", "POST"])
+def change_pwd():
+    if request.method == "POST":
+        pwd_old = request.form["password_old"]
+        pwd_new1 = request.form["password_new1"]
+        pwd_new2 = request.form["password_new2"]
+        print(f" >>{pwd_old} {pwd_new1} {pwd_new2}")
+        print(f"cp: {current_user.name}")
+        if current_user.check_password(pwd_old):
+            if pwd_new1 == pwd_new2:
+                current_user.set_password(pwd_new2)
+                db.session.commit()
+                return redirect(url_for("lists.home"))
+            flash("New Passwords are not identical")
+        flash("Invalid credentials")
+        Log.info(f"Authorization failure for user '{request.form["name"]}' ")
+
+        return render_template(url_for("lists.home"))
+    return render_template("change_pwd.html")