import streamlit as st
import importlib
from io import BytesIO
import time

st.set_page_config(page_title="Multilingual Translator", page_icon="🌐", layout="centered")

def main():
    translation = importlib.import_module("translation")
    lang_detect = importlib.import_module("lang_detect")
    audio_processor = importlib.import_module("audio_processor")

    st.markdown("<h1 style='text-align: center; color: #2E86C1;'>Multilingual Translator</h1>", unsafe_allow_html=True)
    st.markdown("<p style='text-align: center; color: #666;'>Translate text like Google Translate</p>", unsafe_allow_html=True)

    col1, col2 = st.columns([1, 1])
    with col1:
        st.markdown("<div style='margin-bottom: 10px;'></div>", unsafe_allow_html=True)
        input_type = st.radio("Input", ["Text", "File Upload"], horizontal=True, label_visibility="collapsed", key="input_type")
        user_text = st.text_area("Enter or paste text", height=200, key="text_input").strip() if input_type == "Text" else ""
        if input_type == "File Upload":
            doc_file = st.file_uploader("Upload TXT File", type=["txt"], key="doc_input", accept_multiple_files=False, label_visibility="collapsed")
            user_text = doc_file.read().decode("utf-8").strip() if doc_file else ""

        if user_text:
            start_time = time.time()
            detected_options = lang_detect.detect_language(user_text) if len(user_text) >= 10 else [("English", 1.0, "English")]
            source_lang = detected_options[0][0] if detected_options else "English"

            native_lang_map = {
                "English": "English", "French": "Français", "Spanish": "Español",
                "German": "Deutsch", "Hindi": "हिन्दी", "Chinese": "中文",
                "Arabic": "العربية", "Russian": "Русский", "Japanese": "日本語"
            }
            source_options = ["Detect"] + [native_lang_map.get(lang, lang) for lang, _, _ in detected_options] + list(native_lang_map.values())
            target_options = list(native_lang_map.values())

            source_lang_display = st.selectbox("From", source_options, index=0, key="source_lang").replace("Detect", native_lang_map.get(source_lang, source_lang))
            source_lang = next((k for k, v in native_lang_map.items() if v == source_lang_display), source_lang)

            target_lang_display = st.selectbox("To", target_options, index=target_options.index("हिन्दी") if "हिन्दी" in target_options else 0, key="target_lang")
            target_lang = next((k for k, v in native_lang_map.items() if v == target_lang_display), "Hindi")

            if st.button("Translate", key="translate_btn"):
                with st.spinner("Translating..."):
                    try:
                        translated_text = translation.translate(user_text, source_lang, target_lang)
                        st.session_state.translated_text = translated_text
                        st.session_state.translation_time = time.time() - start_time
                    except Exception as e:
                        st.session_state.translated_text = user_text  # Fallback to input
                        st.session_state.translation_time = time.time() - start_time
                        st.warning(f"Translation error: {str(e)}. Using input as fallback.")

    with col2:
        st.markdown("<div style='margin-bottom: 10px;'></div>", unsafe_allow_html=True)
        if "translated_text" in st.session_state and st.session_state.translated_text:
            st.text_area("Translation:", value=st.session_state.translated_text, height=200, key="output_area")
            st.write(f"Translation time: {st.session_state.translation_time:.2f} seconds")
            output_option = st.radio("Output", ["Text", "Audio"], horizontal=True, label_visibility="collapsed", key="output_option")
            if output_option == "Audio":
                audio = audio_processor.text_to_speech(st.session_state.translated_text, target_lang)
                if audio and audio.getbuffer().nbytes > 0:
                    st.audio(audio, format="audio/mp3")
                    st.success("Audio playing.")
                else:
                    st.error("Audio generation failed. Retrying with English...")
                    audio_fallback = audio_processor.text_to_speech(st.session_state.translated_text, "English")
                    if audio_fallback and audio_fallback.getbuffer().nbytes > 0:
                        st.audio(audio_fallback, format="audio/mp3")
                        st.success("Fallback audio in English playing.")
                    else:
                        st.error("Audio generation failed. Try again later.")

    st.markdown("""
        <p style='font-size: small; color: grey; text-align: center; margin-top: 20px;'>
            Developed by: Krishna Prakash <a href='https://www.linkedin.com/in/krishnaprakash-profile/' target='_blank'>
                <img src='https://img.icons8.com/ios-filled/30/0077b5/linkedin.png' alt='LinkedIn' style='vertical-align: middle; margin: 0 5px;'/>
            </a>
        </p>
    """, unsafe_allow_html=True)

if __name__ == "__main__":
    main()