app.py

import gradio as gr
from transformers import AutoTokenizer, T5ForConditionalGeneration
import torch
import os

# Set up device
device = torch.device("cuda" if torch.cuda.is_available() else "cpu")

#access_token = os.getenv["HF_TOKEN"]

# Load model and tokenizer
model_name = "AI-Mock-Interviewer/T5"
tokenizer = AutoTokenizer.from_pretrained(model_name)
model = T5ForConditionalGeneration.from_pretrained(model_name)


# System prompt to guide the interview generation
system_prompt = """
You are conducting a mock technical interview. Generate questions and follow-up questions based on the domain provided. Consider these aspects:
1. The question should be relevant to the domain (e.g., software engineering, machine learning).
2. For follow-up questions, analyze the candidate's last response and ask questions that probe deeper into their understanding, challenge their approach, or request clarification.
3. The follow-up question should aim to explore the candidate's depth of knowledge and ability to adapt.
4. Ensure each question is unique and does not repeat previously asked questions.
5. Ensure each question covers a different sub-topic within the domain, avoiding redundancy.
6. If no clear follow-up can be derived, generate a fresh, related question from a different aspect of the domain.
Important: Ensure that each question is clear, concise, and allows the candidate to demonstrate their technical and communicative abilities effectively.
"""

# Define sub-topic categories for different domains
subtopic_keywords = {
    "data analysis": ["data cleaning", "missing data", "outliers", "feature engineering", "EDA", "trend analysis", "data visualization"],
    "machine learning": ["supervised learning", "unsupervised learning", "model evaluation", "bias-variance tradeoff", "overfitting", "hyperparameter tuning"],
    "software engineering": ["agile methodology", "code optimization", "design patterns", "database design", "testing strategies"],
}

def identify_subtopic(question, domain):
    """Identify the sub-topic of a question using predefined keywords."""
    domain = domain.lower()
    if domain in subtopic_keywords:
        for subtopic in subtopic_keywords[domain]:
            if subtopic in question.lower():
                return subtopic
    return None

def generate_question(prompt, domain, state=None, max_attempts=10):
    """Generate a unique interview question while ensuring no repetition."""
    attempts = 0
    while attempts < max_attempts:
        attempts += 1
        full_prompt = f"{system_prompt.strip()}\n{prompt.strip()}"
        inputs = tokenizer(full_prompt, return_tensors="pt").to(device)
        outputs = model.generate(
            inputs["input_ids"],
            max_new_tokens=50,
            num_return_sequences=1,
            no_repeat_ngram_size=2,
            top_k=30,
            top_p=0.9,
            temperature=0.7,
            do_sample=True,
            pad_token_id=tokenizer.eos_token_id,
        )
        question = tokenizer.decode(outputs[0], skip_special_tokens=True).strip()
        if not question.endswith("?"):
            question = question.split("?")[0] + "?"
        
        subtopic = identify_subtopic(question, domain)

        # Ensure uniqueness within the session state
        if state:
            if question not in state["asked_questions"] and (subtopic is None or subtopic not in state["asked_subtopics"]):
                state["asked_questions"].add(question)
                if subtopic:
                    state["asked_subtopics"].add(subtopic)
                return question

    raise RuntimeError("Failed to generate a unique question after multiple attempts.")

def reset_state(domain, company):
    """Reset session state for a new interview."""
    return {
        "domain": domain,
        "company": company,
        "asked_questions": set(),
        "asked_subtopics": set(),
        "conversation": []  # List of tuples: (speaker, message)
    }

def start_interview(domain, company):
    """Start a new interview session."""
    state = reset_state(domain, company)
    prompt = f"Domain: {domain}. " + (f"Company: {company}. " if company else "") + "Generate the first question:"
    question = generate_question(prompt, domain, state)
    state["conversation"].append(("Interviewer", question))
    return state["conversation"], state

def submit_response(candidate_response, state):
    """Accept the candidate's response, update the conversation, and generate a follow-up question."""
    state["conversation"].append(("Candidate", candidate_response))
    prompt = f"Domain: {state['domain']}. Candidate's last response: {candidate_response}. Generate a follow-up question with a new perspective:"
    question = generate_question(prompt, state["domain"], state)
    state["conversation"].append(("Interviewer", question))
    return state["conversation"], state

# Build an interactive Gradio interface using Blocks
with gr.Blocks() as demo:
    gr.Markdown("# Interactive Mock Interview")
    
    with gr.Row():
        domain_input = gr.Textbox(label="Domain")
        company_input = gr.Textbox(label="Company (Optional)")
    
    start_button = gr.Button("Start Interview")
    chatbot = gr.Chatbot(label="Interview Conversation")
    
    with gr.Row():
        response_input = gr.Textbox(label="Your Response")
        submit_button = gr.Button("Submit")
    
    # Maintain session state across interactions
    state = gr.State({})  # Initialize state properly
    
    # Clicking start initializes the interview and shows the first question
    start_button.click(start_interview, inputs=[domain_input, company_input], outputs=[chatbot, state])
    
    # Submitting a response updates the conversation with a follow-up question
    submit_button.click(submit_response, inputs=[response_input, state], outputs=[chatbot, state]).then(
        lambda _: "", inputs=[response_input], outputs=[response_input]  # Clear response input after submission
    )

demo.launch()