import streamlit as st
from transformers import pipeline
from langdetect import detect

# Title of the app
st.title("Language Translator App")

# Available translation models
MODELS = {
    "English to German": "Helsinki-NLP/opus-mt-en-de",
    "German to English": "Helsinki-NLP/opus-mt-de-en",
    "English to French": "Helsinki-NLP/opus-mt-en-fr",
    "French to English": "Helsinki-NLP/opus-mt-fr-en",
    "English to Spanish": "Helsinki-NLP/opus-mt-en-es",
    "Spanish to English": "Helsinki-NLP/opus-mt-es-en",
    "English to Chinese": "Helsinki-NLP/opus-mt-en-zh",
    "Chinese to English": "Helsinki-NLP/opus-mt-zh-en",
    "English to Russian": "Helsinki-NLP/opus-mt-en-ru",
    "Russian to English": "Helsinki-NLP/opus-mt-ru-en",
    "English to Arabic": "Helsinki-NLP/opus-mt-en-ar",
    "Arabic to English": "Helsinki-NLP/opus-mt-ar-en",
    "English to Hindi": "Helsinki-NLP/opus-mt-en-hi",
    "Hindi to English": "Helsinki-NLP/opus-mt-hi-en",
}

# Sidebar for model selection
st.sidebar.header("Settings")
translation_direction = st.sidebar.selectbox(
    "Choose translation direction",
    list(MODELS.keys())
)

# Load the translation pipeline
@st.cache_resource
def load_translator(model_name):
    return pipeline("translation", model=model_name)

translator = load_translator(MODELS[translation_direction])

# Input text area
st.header("Enter Text to Translate")
input_text = st.text_area("Input Text", "Hello, how are you?")

# Detect language
if input_text.strip() != "":
    try:
        detected_lang = detect(input_text)
        st.subheader("Detected Language")
        st.write(f"The detected language is: **{detected_lang}**")
    except Exception as e:
        st.error(f"Language detection failed: {e}")

# Translate button
if st.button("Translate"):
    if input_text.strip() == "":
        st.warning("Please enter some text to translate.")
    else:
        with st.spinner("Translating..."):
            try:
                translation = translator(input_text)
                translated_text = translation[0]['translation_text']
                st.success("Translation Complete!")
                st.subheader("Translated Text")
                st.write(translated_text)
            except Exception as e:
                st.error(f"Translation failed: {e}")