app.py

import streamlit as st
import cohere
import os

st.set_page_config(page_title="Cohere Chat", layout="wide")

AI_PFP = "media/pfps/cohere-pfp.png"
USER_PFP = "media/pfps/user-pfp.jpg"
BANNER = "media/banner.png"

if not os.path.exists(AI_PFP) or not os.path.exists(USER_PFP):
    st.error("Missing profile pictures in media/pfps directory")
    st.stop()

model_info = {
    "c4ai-aya-expanse-8b": {
        "description": "Aya Expanse is a highly performant 8B multilingual model, designed to rival monolingual performance through innovations in instruction tuning with data arbitrage, preference training, and model merging. Serves 23 languages.",
        "context": "4K",
        "output": "4K"
    },
    "c4ai-aya-expanse-32b": {
        "description": "Aya Expanse is a highly performant 32B multilingual model, designed to rival monolingual performance through innovations in instruction tuning with data arbitrage, preference training, and model merging. Serves 23 languages.",
        "context": "128K",
        "output": "4K"
    },
    "command-a-03-2025": {
        "description": "Command A is our most performant model to date, excelling at tool use, agents, retrieval augmented generation (RAG), and multilingual use cases. Command A has a context length of 256K, only requires two GPUs to run, and has 150% higher throughput compared to Command R+ 08-2024.",
        "context": "256K",
        "output": "8K"
    },
    "command-r7b-12-2024": {
        "description": "command-r7b-12-2024 is a small, fast update delivered in December 2024. It excels at RAG, tool use, agents, and similar tasks requiring complex reasoning and multiple steps.",
        "context": "128K",
        "output": "4K"
    },
    "command-r-plus-04-2024": {
        "description": "Command R+ is an instruction-following conversational model that performs language tasks at a higher quality, more reliably, and with a longer context than previous models. It is best suited for complex RAG workflows and multi-step tool use.",
        "context": "128K",
        "output": "4K"
    },
    "command-r-plus": {
        "description": "command-r-plus is an alias for command-r-plus-04-2024, so if you use command-r-plus in the API, that's the model you're pointing to.",
        "context": "128K",
        "output": "4K"
    },
    "command-r-08-2024": {
        "description": "Updated Command R model from August 2024.",
        "context": "128K",
        "output": "4K"
    },
    "command-r-03-2024": {
        "description": "Instruction-following model for code generation, RAG, and agents.",
        "context": "128K",
        "output": "4K"
    },
    "command-r": {
        "description": "Alias for command-r-03-2024.",
        "context": "128K",
        "output": "4K"
    },
    "command": {
        "description": "Conversational model with long context capabilities.",
        "context": "4K",
        "output": "4K"
    },
    "command-nightly": {
        "description": "Experimental nightly build (not for production).",
        "context": "128K",
        "output": "4K"
    },
    "command-light": {
        "description": "Faster lightweight version of command.",
        "context": "4K",
        "output": "4K"
    },
    "command-light-nightly": {
        "description": "Experimental nightly build of command-light.",
        "context": "128K",
        "output": "4K"
    },
}

with st.sidebar:
    st.image(BANNER, use_container_width=True)
    st.markdown("Hugging Face 🤗 Community UI (Vision Model support coming soon)")
    st.title("Settings")
    api_key = st.text_input("Cohere API Key", type="password")
    selected_model = st.selectbox("Model", options=list(model_info.keys()))
    
    if st.button("Clear Chat"):
        st.session_state.messages = []
        st.session_state.first_message_sent = False
        st.rerun()
        
    st.divider()
    st.image(AI_PFP, width=60)
    st.subheader(selected_model)
    st.markdown(model_info[selected_model]["description"])
    st.caption(f"Context: {model_info[selected_model]['context']}")
    st.caption(f"Output: {model_info[selected_model]['output']}")
    st.markdown("Powered by Cohere's API")

if "messages" not in st.session_state:
    st.session_state.messages = []
    
if "first_message_sent" not in st.session_state:
    st.session_state.first_message_sent = False

if not st.session_state.first_message_sent:
    st.markdown("<h1 style='text-align: center; color: #4a4a4a; margin-top: 100px;'>How can Cohere help you today?</h1>", unsafe_allow_html=True)

for msg in st.session_state.messages:
    with st.chat_message(msg["role"], avatar=USER_PFP if msg["role"] == "user" else AI_PFP):
        st.markdown(msg["content"])

if prompt := st.chat_input("Message..."):
    if not api_key:
        st.error("API key required")
        st.stop()

    st.session_state.first_message_sent = True
    
    st.session_state.messages.append({"role": "user", "content": prompt})
    with st.chat_message("user", avatar=USER_PFP):
        st.markdown(prompt)

    try:
        co = cohere.ClientV2(api_key)
        with st.chat_message("assistant", avatar=AI_PFP):
            response = co.chat(
                model=selected_model,
                messages=st.session_state.messages
            )
            if hasattr(response, "message") and hasattr(response.message, "content"):
                content_items = response.message.content
                reply = "".join(getattr(item, 'text', '') for item in content_items)
            else:
                st.write(response)
                reply = "❗️Couldn't extract reply from the Cohere response."
            st.markdown(reply)

        st.session_state.messages.append({"role": "assistant", "content": reply})

    except Exception as e:
        st.error(f"Error: {str(e)}")