Update app.py

app.py

@@ -1,7 +1,81 @@
+import os
 import gradio as gr
+from openai import OpenAI
 
-def greet(name):
-    return "Hello " + name + "!!"
+# Read your key from env (set this in HF Spaces -> Settings -> Secrets)
+OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
+if not OPENAI_API_KEY:
+    raise RuntimeError("Missing OPENAI_API_KEY environment variable.")
 
-demo = gr.Interface(fn=greet, inputs="text", outputs="text")
-demo.launch()
+client = OpenAI(api_key=OPENAI_API_KEY)
+
+DEFAULT_SYS_PROMPT = "You are a helpful assistant. Be concise and accurate."
+
+def chat_fn(message, history, system_prompt, temperature, model_name):
+    """
+    message: latest user text (str)
+    history: list[dict] like [{'role':'user'|'assistant','content': '...'}, ...]
+    system_prompt: system instructions (str)
+    temperature: float
+    model_name: str (e.g., 'gpt-4o-mini' or 'gpt-5')
+    """
+    # Build messages for the Chat Completions API
+    messages = []
+    if system_prompt and system_prompt.strip():
+        messages.append({"role": "system", "content": system_prompt.strip()})
+    # Append prior turns
+    messages.extend(history or [])
+    # Add the latest user turn
+    messages.append({"role": "user", "content": message})
+
+    # Stream tokens and yield partials for Gradio
+    completion = client.chat.completions.create(
+        model=model_name,
+        messages=messages,
+        temperature=float(temperature),
+        stream=True,
+    )
+
+    partial = ""
+    for chunk in completion:
+        delta = chunk.choices[0].delta
+        if delta and delta.content:
+            partial += delta.content
+            # Yield the *current* partial answer (Gradio replaces the prior one)
+            yield partial
+
+with gr.Blocks(title="OpenAI x Gradio Chat") as demo:
+    gr.Markdown("## OpenAI × Gradio Chat\nA lightweight, streaming chat app.")
+
+    with gr.Row():
+        system_prompt = gr.Textbox(
+            value=DEFAULT_SYS_PROMPT,
+            label="System prompt",
+            lines=2
+        )
+    with gr.Row():
+        model_name = gr.Dropdown(
+            choices=["gpt-4o-mini", "gpt-4o", "gpt-5"],
+            value="gpt-4o-mini",
+            label="Model"
+        )
+        temperature = gr.Slider(0.0, 1.2, value=0.7, step=0.1, label="Temperature")
+
+    chat = gr.ChatInterface(
+        fn=chat_fn,
+        type="messages",                 # use OpenAI-style message dicts
+        additional_inputs=[system_prompt, temperature, model_name],
+        textbox=gr.Textbox(placeholder="Ask me anything…"),
+        examples=["Explain transformers in one paragraph", "Write a dad joke about databases"],
+        cache_examples=False,
+        theme="soft",
+        retry_btn="Regenerate",
+        undo_btn="Remove last",
+        clear_btn="Clear",
+        save_history=True,               # saves chat logs (CSV) in Space filesystem
+        flagging_mode="manual",
+        flagging_options=["👍 Useful", "👎 Not good", "⚠ Inaccurate"],
+    )
+
+if __name__ == "__main__":
+    demo.launch()