added login and logout

login.py

@@ -0,0 +1,69 @@
+import streamlit as st
+from home import Home
+
+def login():
+
+    st.set_page_config(
+        page_title="Login Page",
+        layout="centered",
+        initial_sidebar_state="collapsed"
+    )
+    col1, col2, col3 = st.columns(spec=[1, 3, 1])
+
+    with col2:
+        st.title("Login")
+        username = st.text_input("Email Address", value='johndoe@hr.company.com')
+        password = st.text_input("Password", type="password")
+
+
+        col1, col2 = st.columns(spec=[1,1])
+
+        with col1:
+            if st.button(
+                label="Forgot Password?", 
+                use_container_width=True,
+                type="secondary"
+                ):
+
+                st.info("Please contact your manager or the IT department for a password reset.")
+
+        with col2:
+            if st.button(
+                label="Login", 
+                use_container_width=True,
+                type="primary"
+                ):
+
+                class UnregisteredUser(Exception):
+                    """
+                    Represents an exception when the user is not registered.
+                    """
+
+                    def __init__(self, message="User not registered"):
+                        self.message = message
+                        super().__init__(self.message)
+
+                class IncompleteDetails(Exception):
+                    """
+                    Represents an exception when the user's details are incomplete.
+                    """
+
+                    def __init__(self, message="Incomplete details"):
+                        self.message = message
+                        super().__init__(self.message)
+
+                #imaginary db calls for existing user, if user is in imaginary db, user is logged in
+                try:
+                    if username == "johndoe@hr.company.com" and password == "password":
+                        st.session_state.LOGGED_IN = True
+                        st.switch_page(st.Page(Home, title="Home", icon=":material/home:"))
+
+                    if username == "" or password == "":
+                        raise IncompleteDetails
+
+                    raise UnregisteredUser
+
+                except UnregisteredUser as e:
+                    st.error(e)
+                except IncompleteDetails as e:
+                    st.error(e)