app.py

# app.py
import cv2
import gradio as gr
from ultralytics import YOLO

# ── Config ─────────────────────────────────────────────
MODEL_PATH = "yolov8n.pt"     # modelo pre-entrenado (COCO, clase “person”)
CONF_THRES = 0.3              # confianza mínima
LINE_RATIO = 0.5              # línea virtual en mitad de la altura
# ───────────────────────────────────────────────────────

model = YOLO(MODEL_PATH)

# Estado global para entradas/salidas
memory = {}      # {track_id: previous_cy}
in_count = 0
out_count = 0

def count_people(frame):
    global memory, in_count, out_count

    h, w = frame.shape[:2]
    line_y = int(h * LINE_RATIO)

    # detección + tracking interno (ByteTrack)
    results = model.track(
        frame,
        classes=[0],        # solo “person”
        conf=CONF_THRES,
        persist=True,
        verbose=False
    )

    annotated = frame.copy()
    cv2.line(annotated, (0, line_y), (w, line_y), (0, 255, 255), 2)

    if results:
        for box in results[0].boxes:
            x1, y1, x2, y2 = map(int, box.xyxy[0])
            cx, cy = int((x1 + x2) / 2), int((y1 + y2) / 2)
            tid = int(box.id[0]) if box.id is not None else -1

            # lógica de cruce
            prev_cy = memory.get(tid, cy)
            if prev_cy < line_y <= cy:        # entra
                in_count += 1
            elif prev_cy > line_y >= cy:      # sale
                out_count += 1
            memory[tid] = cy

            # dibujo
            cv2.rectangle(annotated, (x1, y1), (x2, y2), (0, 255, 0), 1)
            cv2.circle(annotated, (cx, cy), 3, (0, 0, 255), -1)
            cv2.putText(annotated, str(tid), (x1, y1 - 5),
                        cv2.FONT_HERSHEY_SIMPLEX, 0.5, (255, 0, 0), 1)

    total = in_count - out_count
    cv2.putText(
        annotated,
        f"In: {in_count}  Out: {out_count}  Ocupación: {total}",
        (10, 30),
        cv2.FONT_HERSHEY_SIMPLEX,
        1,
        (255, 255, 255),
        2
    )

    return annotated, f"In: {in_count} | Out: {out_count} | Ocupación: {total}"

demo = gr.Interface(
    fn=count_people,
    inputs=gr.Image(sources=["webcam"], streaming=True),  # 👈 parámetro correcto
    outputs=[gr.Image(label="Video"), gr.Text(label="Contador")],
    live=True,
    title="Contador de personas (entrada única)"
)

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