src/streamlit_app.py

import os
import tempfile
import logging
import urllib.parse

import requests
import streamlit as st
from gtts import gTTS
from dotenv import load_dotenv
from translatepy import Translator

# -------------------- Load Environment --------------------
load_dotenv()

# -------------------- Configuration --------------------
WIKIPEDIA_API_BASE_URL_PREFIX = ".wikipedia.org/w/api.php"
ENGLISH_SUMMARY_SENTENCES = 5
WIKIMEDIA_HEADERS = {
    'User-Agent': 'WikiHealthNavigator/1.0 (contact@example.com)'
}
REQUEST_TIMEOUT = 30
translator = Translator()

logger = logging.getLogger(__name__)
logger.setLevel(logging.DEBUG)

# -------------------- Wikipedia Summary Fetch --------------------
@st.cache_data(ttl=3600)
def fetch_wikipedia_content(query, lang="en", is_fallback=False):
    if not query:
        return None, None, lang

    title = query.strip()
    encoded_title = urllib.parse.quote(title, safe="")

    rest_url = f"https://{lang}.wikipedia.org/api/rest_v1/page/summary/{encoded_title}"
    try:
        resp = requests.get(rest_url, headers=WIKIMEDIA_HEADERS, timeout=REQUEST_TIMEOUT)
        resp.raise_for_status()
        j = resp.json()
        summary = j.get("extract") or j.get("description")
        full_url = j.get("content_urls", {}).get("desktop", {}).get("page")
        if summary:
            return summary, full_url, lang
    except Exception as e:
        logger.debug("REST failed: %s", e)

    try:
        api = f"https://{lang}{WIKIPEDIA_API_BASE_URL_PREFIX}"
        params = {
            "action": "query",
            "format": "json",
            "formatversion": 2,
            "prop": "extracts|info",
            "inprop": "url",
            "titles": title,
            "redirects": 1,
            "explaintext": True,
            **({"exsentences": ENGLISH_SUMMARY_SENTENCES} if lang == "en" else {})
        }
        res = requests.get(api, params=params, headers=WIKIMEDIA_HEADERS, timeout=REQUEST_TIMEOUT)
        res.raise_for_status()
        pages = res.json().get("query", {}).get("pages", [])
        if pages and not pages[0].get("missing"):
            return pages[0].get("extract"), pages[0].get("fullurl"), lang
    except Exception as e:
        logger.debug("Query API failed: %s", e)

    if not is_fallback and lang != "en":
        return fetch_wikipedia_content(query, lang="en", is_fallback=True)

    return None, None, lang

# -------------------- Wikipedia Image Fetch --------------------
@st.cache_data(ttl=3600)
def fetch_wikipedia_images(query, lang="en", max_images=3):
    if not query:
        return []

    api = f"https://{lang}.wikipedia.org/w/api.php"
    params = {
        "action": "query",
        "format": "json",
        "prop": "pageimages",
        "piprop": "original",
        "titles": query,
        "redirects": 1
    }

    try:
        res = requests.get(api, params=params, headers=WIKIMEDIA_HEADERS, timeout=REQUEST_TIMEOUT)
        res.raise_for_status()
        pages = res.json().get("query", {}).get("pages", {})
        images = []

        for page in pages.values():
            if "original" in page:
                images.append(page["original"]["source"])

        return images[:max_images]
    except Exception as e:
        logger.debug("Image fetch failed: %s", e)
        return []

# -------------------- Narration --------------------
def narrate_text(text, lang_code):
    try:
        clean = text.strip().replace("\n", " ")
        if not clean:
            st.warning("Nothing to narrate.")
            return

        tts = gTTS(text=clean, lang=lang_code)
        with tempfile.NamedTemporaryFile(delete=False, suffix=".mp3") as fp:
            tts.save(fp.name)
            audio_path = fp.name

        st.audio(audio_path, format="audio/mp3")
    except Exception as e:
        st.error(f"Narration error: {e}")

# -------------------- Translation --------------------
def translate_summary(text, target_lang):
    try:
        return translator.translate(text, target_lang).result
    except Exception:
        return text

# -------------------- Streamlit UI --------------------
st.set_page_config(page_title="WikiHealth Navigator", layout="centered")
st.title("🩺 WikiHealth Navigator")
st.markdown("Search health topics using Wikipedia (with images & audio)")

languages = {
    "English": "en",
    "हिन्दी": "hi",
    "తెలుగు": "te",
    "தமிழ்": "ta"
}

col1, col2 = st.columns([2, 3])
with col1:
    selected = st.selectbox("Select Language:", list(languages.keys()))
    lang_code = languages[selected]
with col2:
    query = st.text_input("Enter a health topic:")

if st.button("🔍 Search") and query:
    with st.spinner("Searching Wikipedia..."):
        summary, url, actual_lang = fetch_wikipedia_content(query, lang_code)

        if summary:
            if actual_lang != lang_code:
                summary = translate_summary(summary, lang_code)

            st.subheader("📝 Summary")
            st.write(summary)

            st.subheader("🖼️ Related Images")
            images = fetch_wikipedia_images(query, lang_code)

            if images:
                cols = st.columns(len(images))
                for col, img in zip(cols, images):
                    col.image(img, use_container_width=True)
            else:
                st.info("No images found.")

            if st.button("🔊 Narrate Summary"):
                narrate_text(summary, lang_code)

            if url:
                st.markdown(f"[Read full article on Wikipedia]({url})")
        else:
            st.warning("No information found.")