app.py

import torch
from transformers import ViTImageProcessor, ViTForImageClassification
from fastai.learner import load_learner
from fastai.vision.core import PILImage
from PIL import Image
import matplotlib.pyplot as plt
import numpy as np
import gradio as gr
import io
import base64
import os
import zipfile
import tensorflow as tf

# --- Extraer y cargar modelo TensorFlow desde zip ---
zip_path = "saved_model.zip"
extract_dir = "saved_model"
if not os.path.exists(extract_dir):
    os.makedirs(extract_dir)
    with zipfile.ZipFile(zip_path, 'r') as zip_ref:
        zip_ref.extractall(extract_dir)

model_tf = tf.saved_model.load(extract_dir)
TF_NUM_CLASSES = 7  # asumimos que son las mismas que CLASSES

# Función helper para inferencia TensorFlow
def predict_tf(img: Image.Image):
    try:
        img_resized = img.resize((224,224))
        img_np = np.array(img_resized) / 255.0
        if img_np.shape[-1] == 4:
            img_np = img_np[..., :3]
        img_tf = tf.convert_to_tensor(img_np, dtype=tf.float32)
        img_tf = tf.expand_dims(img_tf, axis=0)

        infer = model_tf.signatures["serving_default"]
        output = infer(img_tf)
        pred = list(output.values())[0].numpy()[0]
        probs = tf.nn.softmax(pred[:TF_NUM_CLASSES]).numpy()
        return probs
    except Exception as e:
        print(f"Error en predict_tf: {e}")
        return np.zeros(TF_NUM_CLASSES)

# --- Cargar modelos ---
MODEL_NAME = "ahishamm/vit-base-HAM-10000-sharpened-patch-32"
feature_extractor = ViTImageProcessor.from_pretrained(MODEL_NAME)
model_vit = ViTForImageClassification.from_pretrained(MODEL_NAME)
model_vit.eval()
model_malignancy = load_learner("ada_learn_malben.pkl")
model_norm2000 = load_learner("ada_learn_skin_norm2000.pkl")

CLASSES = [
    "Queratosis actínica / Bowen", "Carcinoma células basales",
    "Lesión queratósica benigna", "Dermatofibroma",
    "Melanoma maligno", "Nevus melanocítico", "Lesión vascular"
]
RISK_LEVELS = {
    0: {'level': 'Moderado', 'color': '#ffaa00', 'weight': 0.6},
    1: {'level': 'Alto', 'color': '#ff4444', 'weight': 0.8},
    2: {'level': 'Bajo', 'color': '#44ff44', 'weight': 0.1},
    3: {'level': 'Bajo', 'color': '#44ff44', 'weight': 0.1},
    4: {'level': 'Crítico', 'color': '#cc0000', 'weight': 1.0},
    5: {'level': 'Bajo', 'color': '#44ff44', 'weight': 0.1},
    6: {'level': 'Bajo', 'color': '#44ff44', 'weight': 0.1}
}

MALIGNANT_INDICES = [0, 1, 4]  # clases de riesgo alto/crítico

def analizar_lesion_combined(img):
    try:
        img_fastai = PILImage.create(img)
        inputs = feature_extractor(img, return_tensors="pt")
        with torch.no_grad():
            outputs = model_vit(**inputs)
            probs_vit = outputs.logits.softmax(dim=-1).cpu().numpy()[0]
        pred_idx_vit = int(np.argmax(probs_vit))
        pred_class_vit = CLASSES[pred_idx_vit]
        confidence_vit = probs_vit[pred_idx_vit]
    except Exception as e:
        pred_class_vit = "Error"
        confidence_vit = 0.0
        probs_vit = np.zeros(len(CLASSES))

    try:
        pred_fast_malignant, _, probs_fast_mal = model_malignancy.predict(img_fastai)
        prob_malignant = float(probs_fast_mal[1])
    except:
        prob_malignant = 0.0

    try:
        pred_fast_type, _, _ = model_norm2000.predict(img_fastai)
    except:
        pred_fast_type = "Error"

    try:
        probs_tf = predict_tf(img)
        pred_idx_tf = int(np.argmax(probs_tf))
        confidence_tf = probs_tf[pred_idx_tf]
        if pred_idx_tf < len(CLASSES):
            pred_class_tf = "Maligno" if pred_idx_tf in MALIGNANT_INDICES else "Benigno"
        else:
            pred_class_tf = f"Desconocido"
    except:
        pred_class_tf = "Error"
        confidence_tf = 0.0

    colors_bars = [RISK_LEVELS[i]['color'] for i in range(7)]
    fig, ax = plt.subplots(figsize=(8, 3))
    ax.bar(CLASSES, probs_vit*100, color=colors_bars)
    ax.set_title("Probabilidad ViT por tipo de lesión")
    ax.set_ylabel("Probabilidad (%)")
    ax.set_xticks(np.arange(len(CLASSES)))
    ax.set_xticklabels(CLASSES, rotation=45, ha='right')
    ax.grid(axis='y', alpha=0.2)
    plt.tight_layout()
    buf = io.BytesIO()
    plt.savefig(buf, format="png")
    plt.close(fig)
    img_b64 = base64.b64encode(buf.getvalue()).decode("utf-8")
    html_chart = f'<img src="data:image/png;base64,{img_b64}" style="max-width:100%"/>'

    informe = f"""
    <div style="font-family:sans-serif; max-width:800px; margin:auto">
    <h2>🧪 Diagnóstico por 4 modelos de IA</h2>
    <table style="border-collapse: collapse; width:100%; font-size:16px">
        <tr><th style="text-align:left">🔍 Modelo</th><th>Resultado</th><th>Confianza</th></tr>
        <tr><td>🧠 ViT (transformer)</td><td><b>{pred_class_vit}</b></td><td>{confidence_vit:.1%}</td></tr>
        <tr><td>🧬 Fast.ai (clasificación)</td><td><b>{pred_fast_type}</b></td><td>N/A</td></tr>
        <tr><td>⚠️ Fast.ai (malignidad)</td><td><b>{"Maligno" if prob_malignant > 0.5 else "Benigno"}</b></td><td>{prob_malignant:.1%}</td></tr>
        <tr><td>🔬 TensorFlow (saved_model)</td><td><b>{pred_class_tf}</b></td><td>{confidence_tf:.1%}</td></tr>
    </table>
    <br>
    <b>🧪 Recomendación automática:</b><br>
    """

    cancer_risk_score = sum(probs_vit[i] * RISK_LEVELS[i]['weight'] for i in range(7))
    if prob_malignant > 0.7 or cancer_risk_score > 0.6:
        informe += "🚨 <b>CRÍTICO</b> – Derivación urgente a oncología dermatológica"
    elif prob_malignant > 0.4 or cancer_risk_score > 0.4:
        informe += "⚠️ <b>ALTO RIESGO</b> – Consulta con dermatólogo en 7 días"
    elif cancer_risk_score > 0.2:
        informe += "📋 <b>RIESGO MODERADO</b> – Evaluación programada (2-4 semanas)"
    else:
        informe += "✅ <b>BAJO RIESGO</b> – Seguimiento de rutina (3-6 meses)"

    informe += "</div>"
    return informe, html_chart

# Interfaz Gradio
demo = gr.Interface(
    fn=analizar_lesion_combined,
    inputs=gr.Image(type="pil", label="Sube una imagen de la lesión"),
    outputs=[gr.HTML(label="Informe combinado"), gr.HTML(label="Gráfico ViT")],
    title="Detector de Lesiones Cutáneas (ViT + Fast.ai + TensorFlow)",
    description="Comparación entre ViT transformer (HAM10000), dos modelos Fast.ai y un modelo TensorFlow.",
    flagging_mode="never"
)

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