app.py

import os, sys, time, json, sqlite3, textwrap, requests
import gradio as gr

# -------------------------------------------------
# 1. CONFIGURATION
# -------------------------------------------------
MODEL_ID = "gpt2"                                   # always exists; later swap for sqlcoder
API_URL  = f"https://api-inference.huggingface.co/models/{MODEL_ID}"

HF_TOKEN = os.getenv("HF_TOKEN")
if not HF_TOKEN:
    raise RuntimeError(
        "HF_TOKEN not found. Go to Space → Settings → Secrets and add it."
    )

HEADERS = {"Authorization": f"Bearer {HF_TOKEN}"}

DB_PATH     = "company.db"
SCHEMA_FILE = "schema.sql"

# -------------------------------------------------
# 2. UTIL: BUILD DB IF NEEDED
# -------------------------------------------------
def create_db_if_needed():
    if os.path.exists(DB_PATH):
        return
    with open(SCHEMA_FILE) as f, sqlite3.connect(DB_PATH) as conn:
        conn.executescript(f.read())

# -------------------------------------------------
# 3. UTIL: CALL HF MODEL (with token debug)
# -------------------------------------------------
def nlp_to_sql(question: str, schema_ddl: str) -> str:
    prompt = textwrap.dedent(f"""
        Translate the following natural language question into a single valid SQLite SQL query.

        ### Schema
        {schema_ddl}

        ### Question
        {question}

        ### SQL
    """)
    payload = {"inputs": prompt, "parameters": {"max_new_tokens": 64}}

    # ---------- DEBUG ----------
    print("=" * 60, file=sys.stderr)
    print("DEBUG URL:", API_URL, file=sys.stderr)
    print("DEBUG token starts with:", HF_TOKEN[:8], file=sys.stderr)
    # ---------------------------

    try:
        r = requests.post(API_URL, headers=HEADERS, json=payload, timeout=60)
    except Exception as e:
        return f"[ConnErr] {e}"

    # ---------- MORE DEBUG ----------
    print("DEBUG status:", r.status_code, file=sys.stderr)
    print("DEBUG first 200 bytes:", r.text[:200], file=sys.stderr)
    print("=" * 60, file=sys.stderr)
    # -------------------------------

    if r.status_code != 200:
        return f"[API {r.status_code}] {r.text[:100]}"

    try:
        generated = r.json()[0]["generated_text"]
    except Exception as e:
        return f"[JSONErr] {e}"

    return generated.split("### SQL")[-1].strip() or "[Empty SQL]"

# -------------------------------------------------
# 4. PIPELINE
# -------------------------------------------------
def run_pipeline(query: str):
    t0, trace = time.time(), []
    create_db_if_needed()

    with open(SCHEMA_FILE) as f:
        schema = f.read()
    trace.append(("Schema", "loaded"))

    sql = nlp_to_sql(query, schema)
    trace.append(("LLM", sql))

    try:
        with sqlite3.connect(DB_PATH) as conn:
            cur = conn.execute(sql)
            rows = cur.fetchall()
            cols = [d[0] for d in cur.description] if cur.description else []
        result = {"columns": cols, "rows": rows}
        trace.append(("Exec", f"{len(rows)} rows"))
    except Exception as e:
        result = {"error": str(e)}
        trace.append(("Exec error", str(e)))

    trace.append(("Time", f"{time.time() - t0:.2f}s"))
    return sql, json.dumps(result, indent=2), "\n".join(f"{s}: {m}" for s, m in trace)

# -------------------------------------------------
# 5. UI
# -------------------------------------------------
with gr.Blocks(title="Debug HF Token & API") as demo:
    gr.Markdown("### Debugging HF TOKEN → API (uses GPT-2)")
    q = gr.Textbox(label="Question", placeholder="e.g., How many employees?")
    with gr.Row():
        sql_box = gr.Code(label="SQL / debug output")
        res_box = gr.Code(label="Result / error")
    trace_box = gr.Textbox(label="Trace")
    btn = gr.Button("Run")
    btn.click(run_pipeline, q, [sql_box, res_box, trace_box])

if __name__ == "__main__":
    demo.launch()