app.py

import streamlit as st
from groq import Groq
import requests

# =======================
# API Clients
# =======================
client = Groq(api_key=st.secrets["GROQ_API_KEY"])
HF_API_KEY = st.secrets["HF_API_KEY"]

# =======================
# Sidebar Settings
# =======================
st.sidebar.title("⚙️ Settings")
provider_choice = st.sidebar.radio(
    "Choose Provider",
    ["Groq", "Hugging Face"]
)

if provider_choice == "Groq":
    model_choice = st.sidebar.selectbox(
        "Choose Groq Model",
        ["llama-3.1-8b-instant", "llama-3.1-70b-versatile", "mixtral-8x7b-32768"]
    )
else:
    model_choice = st.sidebar.selectbox(
        "Choose HF Model",
        ["mistralai/Mixtral-8x7B-Instruct-v0.1", "tiiuae/falcon-7b-instruct"]
    )

st.title("🤖 CodeCraft AI - Mini Copilot (Chat Edition)")

# =======================
# Session state for chats
# =======================
if "generate_chat" not in st.session_state:
    st.session_state.generate_chat = []
if "debug_chat" not in st.session_state:
    st.session_state.debug_chat = []
if "explain_chat" not in st.session_state:
    st.session_state.explain_chat = []


# =======================
# Helper functions
# =======================
def call_groq(chat_history, system_prompt):
    response = client.chat.completions.create(
        model=model_choice,
        messages=[{"role": "system", "content": system_prompt}]
                 + [{"role": role, "content": msg} for role, msg in chat_history],
        temperature=0.4
    )
    return response.choices[0].message.content


def call_hf(prompt):
    headers = {"Authorization": f"Bearer {HF_API_KEY}"}
    payload = {"inputs": prompt}
    response = requests.post(
        f"https://api-inference.huggingface.co/models/{model_choice}",
        headers=headers,
        json=payload,
        timeout=60
    )
    if response.status_code == 200:
        result = response.json()
        if isinstance(result, list) and "generated_text" in result[0]:
            return result[0]["generated_text"]
        else:
            return str(result)
    return f"⚠️ HF Error: {response.text}"


def get_ai_response(chat_history, system_prompt):
    if provider_choice == "Groq":
        return call_groq(chat_history, system_prompt)
    else:
        # Convert history into plain text prompt for Hugging Face
        prompt = system_prompt + "\n\n"
        for role, msg in chat_history:
            prompt += f"{role.upper()}: {msg}\n"
        return call_hf(prompt)


# =======================
# Chat UI
# =======================
def chat_ui(tab_name, chat_history, system_prompt, input_key):
    st.subheader(tab_name)

    # --- Chat history display ---
    with st.container():
        for role, msg in chat_history:
            if role == "user":
                with st.chat_message("user"):
                    st.write(msg)
            else:
                with st.chat_message("assistant"):
                    if "```" in msg:  # detect code blocks
                        parts = msg.split("```")
                        for i, part in enumerate(parts):
                            if i % 2 == 1:  # inside code block
                                lang, *code_lines = part.split("\n")
                                code = "\n".join(code_lines)
                                st.code(code, language=lang if lang else "python")
                            else:
                                st.write(part)
                    else:
                        st.write(msg)

    # --- Input bar + send button in one row ---
    col1, col2 = st.columns([10, 1])
    with col1:
        user_input = st.text_input(
            "Type your message...",
            key=input_key,
            label_visibility="collapsed"
        )
    with col2:
        send_btn = st.button("➤", key=input_key + "_send")

    # --- Handle input ---
    if send_btn and user_input.strip():
        chat_history.append(("user", user_input.strip()))

        with st.spinner("Thinking..."):
            ai_msg = get_ai_response(chat_history, system_prompt)

        chat_history.append(("assistant", ai_msg))
        st.session_state[input_key] = ""  # clear input
        st.rerun()


# =======================
# Tabs
# =======================
tab1, tab2, tab3 = st.tabs(["💡 Generate Code", "🛠 Debug Code", "📘 Explain Code"])

with tab1:
    chat_ui(
        "💡 Generate Code",
        st.session_state.generate_chat,
        "You are a helpful coding assistant. Generate correct code first, then a short simple explanation.",
        input_key="generate_input"
    )

with tab2:
    chat_ui(
        "🛠 Debug Code",
        st.session_state.debug_chat,
        "You are an expert code debugger. Fix errors and give corrected code, then explain what changed and why in simple terms.",
        input_key="debug_input"
    )

with tab3:
    chat_ui(
        "📘 Explain Code",
        st.session_state.explain_chat,
        "You are a teacher that explains code in simple words. The user pastes code, and you explain step by step.",
        input_key="explain_input"
    )

# =======================
# Footer
# =======================
st.markdown("---")
st.caption("🚀 Built for Hackathons using Streamlit + Hugging Face + Groq")