app.py

# Standardbibliotheken
import os          # Umgebungsvariablen (z.B. HF_TOKEN)
import time        # Timing / Performance-Messung
import random      # Zufallswerte (z.B. Beispiel-Reviews)
import html        # HTML-Escaping für sichere Ausgabe in Gradio
import types       # Monkeypatching von Instanzen (fastText .predict)
import numpy as np # Numerische Arrays und Wahrscheinlichkeiten

# Machine Learning / NLP
import torch       # PyTorch: Modelle, Tensoren, Devices
import fasttext    # Sprach-ID-Modell (lid.176)
# Folgende sind notwendig, auch wenn sie nicht explizit genutzt werden:
import sentencepiece  # Pflicht für SentencePiece-basierte Tokenizer (z.B. DeBERTa v3)
import tiktoken       # Optionaler Converter (verhindert Fallback-Fehler bei Tokenizer)
from langid.langid import LanguageIdentifier, model  # Alternative Sprach-ID

# Hugging Face Ökosystem
import spaces                                     # HF Spaces-Dekoratoren (@spaces.GPU)
from transformers import AutoTokenizer            # Tokenizer laden (use_fast=False für DeBERTa v3)
from huggingface_hub import hf_hub_download       # Download von Dateien/Weights aus dem HF Hub
from safetensors.torch import load_file           # Sicheres & schnelles Laden von Weights (.safetensors)

# Übersetzung
import deepl  # DeepL API für automatische Übersetzung

# UI / Serving
import gradio as gr  # Web-UI für Demo/Spaces

# Projektspezifische Module
from lib.bert_regressor import BertMultiHeadRegressor
from lib.bert_regressor_utils import (
    predict_flavours,  # Hauptfunktion: Vorhersage der 8 Aromenachsen
)
from lib.wheel import build_svg_with_values       # SVG-Rendering für Flavour Wheel
from lib.examples import EXAMPLES                 # Beispiel-Reviews (vordefiniert)

### Stettings ####################################################################

MODEL_BASE = "microsoft/deberta-v3-base"
REPO_ID    = "ziem-io/deberta_flavour_regressor_multi_head"

# (optional) falls das Model-Repo privat ist:
HF_TOKEN = os.getenv("HF_TOKEN")  # in Space-Secrets hinterlegen
MODEL_FILE = os.getenv("MODEL_FILE")  # in Space-Secrets hinterlegen
DEEPL_API_KEY = os.getenv("DEEPL_API_KEY")  # in Space-Secrets hinterlegen

##################################################################################

# --- Download Weights ---
weights_path = hf_hub_download(
    repo_id=REPO_ID, 
    filename=MODEL_FILE, 
    token=HF_TOKEN
)

# --- Tokenizer (SentencePiece!) ---
tokenizer_flavours = AutoTokenizer.from_pretrained(
    MODEL_BASE, 
    use_fast=False
)

model_flavours = BertMultiHeadRegressor(
    pretrained_model_name=MODEL_BASE
)
state = load_file(weights_path)                          # safetensors -> dict[str, Tensor]
_ = model_flavours.load_state_dict(state, strict=False)  # strict=True wenn Keys exakt passen

device = "cuda" if torch.cuda.is_available() else "cpu"
model_flavours.to(device).eval()

### Check if lang is english #####################################################

ID = LanguageIdentifier.from_modelstring(model, norm_probs=True)

def _is_eng(text: str, min_chars: int = 6, threshold: float = 0.1):
    t = (text or "").strip()
    if len(t) < min_chars:
        return True, 0.0
    lang, prob = ID.classify(t)  # prob ∈ [0,1]
    return (lang == "en" and prob >= threshold), float(prob)

def _translate_en(text: str, target_lang: str = "EN-GB"):
    deepl_client = deepl.Translator(DEEPL_API_KEY)
    result = deepl_client.translate_text(text, target_lang=target_lang)
    return result.text

### Do actual prediction #########################################################
@spaces.GPU(duration=10)  # Sekunden GPU-Zeit pro Call
def predict(review: str):

    review = (review or "").strip()
    is_translated = False
    html_info_out = ""

    # Abort if no text if given
    if not review:
        # immer drei Outputs zurückgeben
        return "Please enter a review.", "", {}
    
    # Check for lang of text
    review_is_eng, review_lang_prob = _is_eng(review)

    # Abort if text is not english
    if not review_is_eng:
        review = _translate_en(review)
        html_info_out = f"""<strong style='margin-bottom: 0.5em'>Your text has been automatically translated:</strong>
        <p>{review}</p>
        """
        is_translated = True
    
    prediction_flavours = {}
    prediction_flavours_list = [0, 0, 0, 0, 0, 0, 0, 0]

    # Do actual predictions if is english and whisky note
    t_start_flavours = time.time()
    prediction_flavours = predict_flavours(review, model_flavours, tokenizer_flavours, device)
    prediction_flavours_list = list(prediction_flavours.values())
    t_end_flavours = time.time()

    html_wheel_out = build_svg_with_values(prediction_flavours_list)

    json_out = {
        "result": dict(prediction_flavours.items()),
        "review": review,
        "model": MODEL_FILE,
        "device": device,
        "translated": is_translated,
        "duration": round((t_end_flavours - t_start_flavours), 3),
    }

    return html_info_out, html_wheel_out, json_out

##################################################################################

def random_text():
    return random.choice(EXAMPLES)

def _start_text():
    return EXAMPLES[20]

def _get_device_info():
    if torch.cuda.is_available():
        return f"◉ Runs on GPU: {torch.cuda.get_device_name(0)}"
    else:
        return "◎ Runs on CPU (May be slower)"

### Create Form interface with Gradio Framework ##################################
custom_css = """
@media (prefers-color-scheme: dark) {
    svg#wheel > text {
        fill: rgb(200, 200, 200);
    }
}
"""

with gr.Blocks(css=custom_css) as demo:
    gr.HTML("<h2>Multi-Axis Regression of Whisky Tasting Notes</h2>")
    gr.HTML("""
    <h3>Automatically turns Whisky Tasting Notes into Flavour Wheels.</h3>
    <p>This model is a fine-tuned version of <a href='https://huggingface.co/microsoft/deberta-v3-base'>microsoft/deberta-v3-base</a> designed to analyze English whisky tasting notes. It predicts the intensity of eight sensory categories — <strong>grainy</strong>, <strong>grassy</strong>, <strong>fragrant</strong>, <strong>fruity</strong>, <strong>peated</strong>, <strong>woody</strong>, <strong>winey</strong> and <strong>off-notes</strong> — on a continuous scale from 0 (none) to 4 (extreme).</p>
""")

    gr.HTML("""
    <p style='color: var(--block-title-text-color)'>Learn more about use cases and get in touch at <a href='https://www.whisky-wheel.com'>www.whisky-wheel.com</a></p>
""")
    
    #gr.HTML(f"<span style='color: var(--block-title-text-color)'>{_get_device_info()}</span>")

    with gr.Row():  # alles nebeneinander
        with gr.Column(scale=1):  # linke Seite: Input
            review_box = gr.Textbox(
                label="Whisky Review",
                lines=8,
                placeholder="Enter whisky review",
                value=_start_text(),
            )
            gr.HTML("<div style='color: gray; font-size: 0.9em;'>Note: Non-English texts will be automatically translated.</div>")
            
            with gr.Row():
                replace_btn = gr.Button("Load Example", variant="secondary", scale=1)
                submit_btn  = gr.Button("Submit", variant="primary", scale=1)

        with gr.Column(scale=1):  # rechte Seite: Output
            html_info_out = gr.HTML(label="Info")
            html_wheel_out = gr.HTML(label="Flavour Wheel")
            json_out = gr.JSON(label="JSON")

    # Events
    submit_btn.click(predict, inputs=review_box, outputs=[html_info_out, html_wheel_out, json_out])
    replace_btn.click(random_text, outputs=review_box)

demo.launch(show_api=False)