project.py

from textblob import TextBlob
import sys
import random
from termcolor import colored
import json
from datetime import datetime

def analyze_sentiment(text):

    # Analyze the sentiment of input text.
    # Returns a dictionary containing polarity, subjectivity, and category.

    if not isinstance(text, str) or not text.strip():
        raise ValueError("Input must be a non-empty string")
    
    analysis = TextBlob(text)
    polarity = analysis.sentiment.polarity
    subjectivity = analysis.sentiment.subjectivity
    
    # Determine sentiment category
    if polarity > 0.3:
        category = "very positive"
    elif polarity > 0:
        category = "positive"
    elif polarity == 0:
        category = "neutral"
    elif polarity > -0.3:
        category = "negative"
    else:
        category = "very negative"
        
    return {
        "polarity": polarity,
        "subjectivity": subjectivity,
        "category": category
    }

def get_response(sentiment_category):
    
    # Generate appropriate response based on sentiment category.
    # Returns a string containing the chatbot's response.
    
    if not isinstance(sentiment_category, str):
        raise ValueError("Sentiment category must be a string")
    
    responses = {
        "very positive": [
            "That's wonderful to hear! Your positive energy is contagious!",
            "Wow, you seem to be having a great day! Tell me more!",
            "Your enthusiasm is inspiring! Keep that amazing attitude!"
        ],
        "positive": [
            "I'm glad you're feeling good! Keep that positive spirit!",
            "Nice to hear something positive! What's making you happy?",
            "Sounds like things are going well for you!"
        ],
        "neutral": [
            "I understand. Would you like to tell me more about that?",
            "Interesting. Can you elaborate on your thoughts?",
            "Sometimes neutral feelings can be complex. What's on your mind?"
        ],
        "negative": [
            "I'm sorry you're feeling down. Would you like to talk about it?",
            "That sounds challenging. How can I help you through this?",
            "It seems like you're going through a tough time. I'm here to listen."
        ],
        "very negative": [
            "I hear that you're going through a very difficult time. I'm here to listen and support you.",
            "This sounds incredibly tough. Would you like to share more about what's troubling you?",
            "I'm truly sorry you're experiencing such intense negative emotions. Can I help in any way?"
        ]
    }
    
    
    sentiment_category = sentiment_category.lower()
    if sentiment_category not in responses:
        raise ValueError("Invalid sentiment category")
        
    return random.choice(responses[sentiment_category])

def save_conversation(conversation_history, filename="chat_history.json"):
    
    # Save the conversation history to a JSON file.
    # Returns True if successful, raises an exception if not.
    
    if not isinstance(conversation_history, list):
        raise ValueError("Conversation history must be a list")
    
    try:
        with open(filename, 'w') as f:
            json.dump(conversation_history, f, indent=4)
        return True
    except Exception as e:
        raise IOError(f"Error saving conversation: {str(e)}")

def format_message(speaker, message, sentiment=None):
    
    # Format a chat message with timestamp and optional sentiment.
    # Returns a dictionary containing the formatted message.
    
    if not isinstance(speaker, str) or not isinstance(message, str):
        raise ValueError("Speaker and message must be strings")
    
    timestamp = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
    
    if sentiment:
        return {
            "timestamp": timestamp,
            "speaker": speaker,
            "message": message,
            "sentiment": sentiment
        }
    return {
        "timestamp": timestamp,
        "speaker": speaker,
        "message": message
    }

def main():
    conversation_history = []
    
    # Welcome message
    print(colored("Welcome to Sentiment Analysis Chatbot!", "cyan"))
    name = input(colored("What's your name? ", "cyan")).strip()
    
    if not name:
        name = "User"
    
    print(colored(f"\nHello {name}! Type 'quit' or 'exit' or 'bye' or 'goodbye' to end the conversation.", "cyan"))
    print(colored("\nBot: How are you feeling today?", "green"))
    
    while True:
        try:
            # Get user input
            user_input = input(colored(f"\n{name}: ", "yellow")).strip()
            
            # Check for exit command
            if user_input.lower() in ['quit', 'exit', 'bye', 'goodbye']:
                print(colored("\nBot: Goodbye! Take care!", "green"))
                save_conversation(conversation_history)
                print(colored("\nConversation saved to chat_history.json!", "cyan"))
                break
            
            # Analyze sentiment
            sentiment = analyze_sentiment(user_input)
            
            # Store user message
            user_message = format_message(name, user_input, sentiment)
            conversation_history.append(user_message)
            
            # Generate and display bot response
            bot_response = get_response(sentiment["category"])
            print(colored(f"\nBot: {bot_response}", "green"))
            
            # Store bot message
            bot_message = format_message("Bot", bot_response)
            conversation_history.append(bot_message)
            
            # Display sentiment analysis
            print(colored(
                f"\nSentiment Analysis: {sentiment['category'].title()} "
                f"(Polarity: {sentiment['polarity']:.2f}, "
                f"Subjectivity: {sentiment['subjectivity']:.2f})",
                "magenta"
            ))
            
        except KeyboardInterrupt:
            print(colored("\n\nChatbot terminated by user.", "red"))
            break
        except Exception as e:
            print(colored(f"\nAn error occurred: {str(e)}", "red"))
            continue

if __name__ == "__main__":
    main()