import gradio as gr
from collections import deque, Counter

# =====================
# STATE
# =====================
history = deque(maxlen=200)
last10 = deque(maxlen=10)

# =====================
# HELPERS
# =====================
def bs(n):
    return "S" if n <= 4 else "B"

def run_length(data):
    if len(data) < 2:
        return 1
    r = 1
    for i in range(len(data)-1, 0, -1):
        if data[i] == data[i-1]:
            r += 1
        else:
            break
    return r

def bias_ratio(data):
    if not data:
        return 0.5
    c = Counter(data)
    return c["B"] / len(data)

# =====================
# PREDICTION ENGINE
# =====================
def predict():
    if len(history) < 15:
        return "WAIT", 0.50, "Not enough data"

    data = list(history)

    w5 = data[-5:]
    w8 = data[-8:]
    w13 = data[-13:]

    b5 = bias_ratio(w5)
    b8 = bias_ratio(w8)
    b13 = bias_ratio(w13)

    avg_bias = (b5 + b8 + b13) / 3
    run = run_length(data)

    pred = "BIG" if avg_bias >= 0.5 else "SMALL"

    # confidence (PDF-inspired)
    conf = 0.55

    if run <= 2:
        conf += 0.08
    elif run == 3:
        conf += 0.03
    else:
        conf -= 0.15

    if abs(b5 - b13) < 0.15:
        conf += 0.05
    else:
        conf -= 0.05

    conf = max(0.35, min(conf, 0.75))

    status = "GO" if conf >= 0.60 else "WARN"
    return pred, round(conf, 2), status

# =====================
# INPUT HANDLER
# =====================
def add_number(n):
    n = int(n)
    history.append(bs(n))
    last10.append(str(n))

    pred, conf, status = predict()

    hist_view = "  ".join(last10)
    out = f"""
Prediction : {pred}
Confidence : {conf}
Status     : {status}
"""

    return hist_view, out

# =====================
# UI
# =====================
with gr.Blocks(theme=gr.themes.Soft()) as demo:
    gr.Markdown("## 🧠 Big / Small Engine (Rule + Short Memory)")

    hist_box = gr.Textbox(label="Last 10 Inputs", interactive=False)
    out_box = gr.Textbox(label="Engine Output", lines=5)

    with gr.Row():
        for i in range(10):
            btn = gr.Button(str(i))
            btn.click(
                fn=add_number,
                inputs=gr.Number(value=i, visible=False),
                outputs=[hist_box, out_box]
            )

demo.launch()