Local Encrypted Chat Record Manager

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import tkinter as tk
from tkinter import ttk, scrolledtext, messagebox, simpledialog
import json
import os
from datetime import datetime
from cryptography.fernet import Fernet
import hashlib
import base64
from pathlib import Path
import threading
import time

class SecureChatManager:
    def __init__(self):
        self.data_dir = Path("secure_chats")
        self.data_dir.mkdir(exist_ok=True)
        self.key_file = self.data_dir / "master.key"
        self.chats_file = self.data_dir / "encrypted_chats.enc"
        self.master_key = self.load_or_create_master_key()
        self.cipher = Fernet(self.master_key)
        self.chats = self.load_chats()
        self.current_chat_id = None
        self.root = None
        
    def load_or_create_master_key(self):
        if self.key_file.exists():
            with open(self.key_file, 'rb') as f:
                return f.read()
        else:
            key = Fernet.generate_key()
            with open(self.key_file, 'wb') as f:
                f.write(key)
            # Set restrictive permissions
            os.chmod(self.key_file, 0o600)
            return key
    
    def encrypt_data(self, data):
        return self.cipher.encrypt(json.dumps(data).encode())
    
    def decrypt_data(self, encrypted_data):
        try:
            decrypted = self.cipher.decrypt(encrypted_data)
            return json.loads(decrypted.decode())
        except Exception:
            messagebox.showerror("Error", "Failed to decrypt data. Wrong key or corrupted file.")
            return {}
    
    def load_chats(self):
        if self.chats_file.exists():
            try:
                with open(self.chats_file, 'rb') as f:
                    encrypted = f.read()
                return self.decrypt_data(encrypted)
            except Exception:
                return {}
        return {}
    
    def save_chats(self):
        try:
            encrypted = self.encrypt_data(self.chats)
            with open(self.chats_file, 'wb') as f:
                f.write(encrypted)
            os.chmod(self.chats_file, 0o600)
        except Exception as e:
            messagebox.showerror("Error", f"Failed to save chats: {str(e)}")
    
    def create_chat(self, title):
        chat_id = hashlib.md5(f"{title}{datetime.now()}".encode()).hexdigest()[:12]
        self.chats[chat_id] = {
            "title": title,
            "messages": [],
            "created_at": datetime.now().isoformat(),
            "last_updated": datetime.now().isoformat()
        }
        self.save_chats()
        return chat_id
    
    def add_message(self, chat_id, sender, content):
        if chat_id not in self.chats:
            return False
        self.chats[chat_id]["messages"].append({
            "sender": sender,
            "content": content,
            "timestamp": datetime.now().isoformat()
        })
        self.chats[chat_id]["last_updated"] = datetime.now().isoformat()
        self.save_chats()
        return True
    
    def get_chat_list(self):
        return sorted(
            [(cid, data["title"], data["last_updated"]) for cid, data in self.chats.items()],
            key=lambda x: x[2],
            reverse=True
        )
    
    def get_chat(self, chat_id):
        return self.chats.get(chat_id, None)
    
    def delete_chat(self, chat_id):
        if chat_id in self.chats:
            del self.chats[chat_id]
            self.save_chats()
            return True
        return False

class ChatGUI:
    def __init__(self):
        self.manager = SecureChatManager()
        self.setup_ui()
        self.refresh_chat_list()
        
    def setup_ui(self):
        self.root = tk.Tk()
        self.root.title("SecureChat • Local • Encrypted")
        self.root.geometry("1000x700")
        self.root.configure(bg="#f0f4f8")
        
        # Soft color palette
        self.colors = {
            "bg": "#f0f4f8",
            "sidebar": "#e6edf5",
            "accent": "#7c9cb8",
            "text": "#2c3e50",
            "message_user": "#a8d5ba",
            "message_other": "#d4e0f0",
            "input_bg": "#ffffff"
        }
        
        self.root.configure(bg=self.colors["bg"])
        
        # Main container
        main_frame = tk.Frame(self.root, bg=self.colors["bg"])
        main_frame.pack(fill=tk.BOTH, expand=True, padx=10, pady=10)
        
        # Sidebar
        sidebar = tk.Frame(main_frame, bg=self.colors["sidebar"], width=280, relief=tk.RAISED, bd=1)
        sidebar.pack(side=tk.LEFT, fill=tk.Y, padx=(0, 8))
        sidebar.pack_propagate(False)
        
        # Header
        header = tk.Frame(sidebar, bg=self.colors["accent"], height=60)
        header.pack(fill=tk.X)
        header.pack_propagate(False)
        
        tk.Label(header, text="🔒 SecureChat", font=("Helvetica", 18, "bold"), 
                fg="white", bg=self.colors["accent"]).pack(pady=15)
        
        # New chat button
        new_btn = tk.Button(sidebar, text="+ New Conversation", font=("Helvetica", 11, "bold"),
                          bg="#5a8a9e", fg="white", relief=tk.FLAT, height=2,
                          command=self.new_chat)
        new_btn.pack(pady=15, padx=15, fill=tk.X)
        
        # Chat list
        tk.Label(sidebar, text="Conversations", font=("Helvetica", 10, "bold"),
                bg=self.colors["sidebar"], fg=self.colors["text"], anchor="w").pack(padx=15, pady=(10,5))
        
        self.chat_listbox = tk.Listbox(sidebar, bg="white", font=("Helvetica", 10),
                                     selectbackground=self.colors["accent"], relief=tk.FLAT,
                                     highlightthickness=0)
        self.chat_listbox.pack(fill=tk.BOTH, expand=True, padx=15, pady=(0,15))
        self.chat_listbox.bind('<<ListboxSelect>>', self.on_chat_select)
        
        # Main chat area
        chat_area = tk.Frame(main_frame, bg=self.colors["bg"])
        chat_area.pack(side=tk.RIGHT, fill=tk.BOTH, expand=True)
        
        # Chat header
        self.chat_header = tk.Frame(chat_area, bg=self.colors["accent"], height=55)
        self.chat_header.pack(fill=tk.X)
        self.chat_header.pack_propagate(False)
        
        self.title_label = tk.Label(self.chat_header, text="Select or create a conversation", 
                                  font=("Helvetica", 14, "bold"), fg="white", 
                                  bg=self.colors["accent"], anchor="w")
        self.title_label.pack(side=tk.LEFT, padx=20, pady=15)
        
        # Messages area
        self.messages_area = scrolledtext.ScrolledText(chat_area, wrap=tk.WORD, font=("Helvetica", 11),
                                                      bg="#f8fafc", fg=self.colors["text"], 
                                                      relief=tk.FLAT, padx=15, pady=15)
        self.messages_area.pack(fill=tk.BOTH, expand=True, padx=10, pady=10)
        self.messages_area.config(state=tk.DISABLED)
        
        # Input area
        input_frame = tk.Frame(chat_area, bg=self.colors["bg"])
        input_frame.pack(fill=tk.X, padx=10, pady=(0,10))
        
        self.input_text = tk.Text(input_frame, height=4, font=("Helvetica", 11),
                                bg=self.colors["input_bg"], relief=tk.SOLID, bd=1)
        self.input_text.pack(side=tk.LEFT, fill=tk.BOTH, expand=True, padx=(0,8))
        
        send_btn = tk.Button(input_frame, text="Send", font=("Helvetica", 11, "bold"),
                           bg=self.colors["accent"], fg="white", width=10, height=2,
                           command=self.send_message)
        send_btn.pack(side=tk.RIGHT)
        
        # Status bar
        self.status = tk.Label(self.root, text="All conversations encrypted locally • Never leaves your device", 
                             bg="#e6edf5", fg="#546e7a", font=("Helvetica", 9), anchor="w")
        self.status.pack(side=tk.BOTTOM, fill=tk.X, ipady=4, padx=10)
        
        # Keyboard binding
        self.root.bind('<Control-Return>', lambda e: self.send_message())
        
        self.current_chat_id = None
    
    def refresh_chat_list(self):
        self.chat_listbox.delete(0, tk.END)
        for chat_id, title, last_updated in self.manager.get_chat_list():
            dt = datetime.fromisoformat(last_updated)
            time_str = dt.strftime("%b %d, %H:%M")
            self.chat_listbox.insert(tk.END, f"{title}  •  {time_str}")
            self.chat_listbox.itemconfig(tk.END, {'fg': '#2c3e50'})
    
    def new_chat(self):
        title = simpledialog.askstring("New Conversation", "Conversation title:", 
                                     initialvalue=f"Chat {datetime.now().strftime('%b %d')}")
        if title and title.strip():
            chat_id = self.manager.create_chat(title.strip())
            self.refresh_chat_list()
            self.load_chat(chat_id)
    
    def on_chat_select(self, event):
        selection = self.chat_listbox.curselection()
        if not selection:
            return
        index = selection[0]
        chat_list = self.manager.get_chat_list()
        if index < len(chat_list):
            chat_id = chat_list[index][0]
            self.load_chat(chat_id)
    
    def load_chat(self, chat_id):
        self.current_chat_id = chat_id
        chat = self.manager.get_chat(chat_id)
        if not chat:
            return
        
        self.title_label.config(text=chat["title"])
        
        self.messages_area.config(state=tk.NORMAL)
        self.messages_area.delete(1.0, tk.END)
        
        for msg in chat["messages"]:
            timestamp = datetime.fromisoformat(msg["timestamp"]).strftime("%H:%M")
            if msg["sender"] == "You":
                prefix = "You"
                color = "#2e7d32"
                align = "right"
            else:
                prefix = "Assistant"
                color = "#1565c0"
                align = "left"
            
            self.messages_area.insert(tk.END, f"{prefix} • {timestamp}\n", "header")
            self.messages_area.insert(tk.END, f"{msg['content']}\n\n", "message")
        
        self.messages_area.tag_config("header", font=("Helvetica", 9, "bold"), foreground=color)
        self.messages_area.tag_config("message", font=("Helvetica", 11), lmargin1=20, lmargin2=20)
        self.messages_area.config(state=tk.DISABLED)
        self.messages_area.see(tk.END)
    
    def send_message(self):
        if not self.current_chat_id:
            messagebox.showinfo("Info", "Please create or select a conversation first.")
            return
        
        content = self.input_text.get("1.0", tk.END).strip()
        if not content:
            return
        
        # Add user message
        self.manager.add_message(self.current_chat_id, "You", content)
        
        # Display immediately
        self.messages_area.config(state=tk.NORMAL)
        timestamp = datetime.now().strftime("%H:%M")
        self.messages_area.insert(tk.END, f"You • {timestamp}\n", "header")
        self.messages_area.insert(tk.END, f"{content}\n\n", "message")
        self.messages_area.tag_config("header", font=("Helvetica", 9, "bold"), foreground="#2e7d32")
        self.messages_area.tag_config("message", font=("Helvetica", 11), lmargin1=20, lmargin2=20)
        self.messages_area.config(state=tk.DISABLED)
        self.messages_area.see(tk.END)
        
        self.input_text.delete("1.0", tk.END)
        
        # Simulate assistant reply (you can replace with real LLM if desired)
        self.root.after(800, self.simulate_reply)
        
        self.refresh_chat_list()
    
    def simulate_reply(self):
        if not self.current_chat_id:
            return
        reply = "Message received and stored securely on your device. All data is encrypted with AES-256."
        self.manager.add_message(self.current_chat_id, "Assistant", reply)
        
        self.messages_area.config(state=tk.NORMAL)
        timestamp = datetime.now().strftime("%H:%M")
        self.messages_area.insert(tk.END, f"Assistant • {timestamp}\n", "header")
        self.messages_area.insert(tk.END, f"{reply}\n\n", "message")
        self.messages_area.tag_config("header", font=("Helvetica", 9, "bold"), foreground="#1565c0")
        self.messages_area.config(state=tk.DISABLED)
        self.messages_area.see(tk.END)
        self.refresh_chat_list()
    
    def run(self):
        self.root.mainloop()

if __name__ == "__main__":
    print("Starting SecureChat - All conversations are encrypted locally")
    print("Data is stored in ./secure_chats/ directory")
    print("Master encryption key is automatically generated and stored securely\n")
    
    app = ChatGUI()
    app.run()