app.py

import streamlit as st
import requests
import feedparser
from datetime import datetime
from openai import OpenAI # The OpenAI library is used, but configured for OpenRouter
from openai import APIStatusError, RateLimitError, AuthenticationError, APIConnectionError
from deep_translator import GoogleTranslator
from bs4 import BeautifulSoup
from dotenv import load_dotenv # Import for loading environment variables
import os # Import for accessing environment variables

# --- CONFIG ------------------------------------------------------------------

# Load environment variables from .env file
load_dotenv()

# --- IMPORTANT: HOW TO SET UP YOUR YOUR OPENROUTER API KEY ---
# 1. Create a file named `.env` in the same directory as your Python script.
# 2. Add the following line to the `.env` file:
#    OPENROUTER_API_KEY="YOUR_OPENROUTER_API_KEY_HERE"
# 3. Replace "YOUR_OPENROUTER_API_KEY_HERE" with your actual API key from OpenRouter.
# 4. Make sure to keep your `.env` file out of version control (e.g., add it to .gitignore).
# --------------------------------------------------------

LANGUAGES = {
    "en": {"en": "English", "hi": "Hindi", "te": "Telugu"},
    "hi": {"en": "अंग्रेज़ी", "hi": "हिंदी", "te": "तेలుగు"},
    "te": {"en": "ఆంగ్లం", "hi": "హిందీ", "te": "తెలుగు"},
}

translations = {
    "en": {
        "title": "🕰️ Timescope",
        "description": "Get today's headlines and explore history — all in one place.",
        "on_this_day": "📅 On This Day in History",
        "pick_date": "Pick a date",
        "language": "🌐 Language",
        "events": "Events:",
        "no_events": "No events found for this date.",
        "todays_headlines": "📢 Today's Headlines by Category",
        "couldnt_load_news": "❌ Couldn’t load news. Please check your internet.",
        "refresh_news": "🔄 Refresh News",
        "ask_ai": "🤖 Ask Timescope AI",
        "ask_placeholder": "Ask anything about history, world news, or events:",
        "answer": "**Answer:** ",
        "ai_error": "❌ AI Assistant Error:", # Changed to be more general for AI
        "unsupported_onthisday": "Sorry, 'On This Day' is not available in this language.",
        "read_more": "Read more"
    },
    "hi": {
        "title": "🕰️ टाइमस्कोप",
        "description": "आज की सुर्खियाँ और इतिहास एक ही स्थान पर देखें।",
        "on_this_day": "📅 आज के दिन का इतिहास",
        "pick_date": "तारीख चुनें",
        "language": "🌐 भाषा",
        "events": "घटनाएँ:",
        "no_events": "इस तारीख के लिए कोई घटना नहीं मिली।",
        "todays_headlines": "📢 आज की प्रमुख खबरें (श्रेणी अनुसार)",
        "couldnt_load_news": "❌ खबरें लोड नहीं हो सकीं। कृपया अपना इंटरनेट जांचें।",
        "refresh_news": "🔄 खबरें रीफ़्रेश करें",
        "ask_ai": "🤖 टाइमस्कोप एआई से पूछें",
        "ask_placeholder": "इतिहास, विश्व समाचार या घटनाओं के बारे में कुछ भी पूछें:",
        "answer": "**उत्तर:** ",
        "ai_error": "❌ AI सहायक त्रुटि:", # Changed
        "unsupported_onthisday": "क्षमा करें, 'आज के दिन' इस भाषा में उपलब्ध नहीं है।",
        "read_more": "और पढ़ें"
    },
    "te": {
        "title": "🕰️ టైమ్‌స్కోప్",
        "description": "ఈ రోజు ముఖ్యాంశాలు మరియు చరిత్రను ఒకే చోట అన్వేషించండి.",
        "on_this_day": "📅 ఈ రోజు చరిత్రలో",
        "pick_date": "తేదీ ఎంచుకోండి",
        "language": "🌐 భాష",
        "events": "ఈవెంట్స్:",
        "no_events": "ఈ తేదీకి ఈవెంట్స్ లభించలేదు.",
        "todays_headlines": "📢 ఈ రోజు ముఖ్యాంశాలు (వర్గం ద్వారా)",
        "couldnt_load_news": "❌ వార్తలు లోడ్ కాలేకపోయాయి. దయచేసి మీ ఇంటర్నెట్‌ను తనిఖీ చేయండి.",
        "refresh_news": "🔄 వార్తలను రీఫ్రెష్ చేయండి",
        "ask_ai": "🤖 టైమ్‌స్కోప్ AI ను అడగండి",
        "ask_placeholder": "చరిత్ర, ప్రపంచ వార్తలు లేదా ఈవెంట్స్ గురించి ఏదైనా అడగండి:",
        "answer": "**సమాధానం:** ",
        "ai_error": "❌ AI సహాయ లోపం:", # Changed
        "unsupported_onthisday": "క్షమించండి, 'ఈ రోజు చరిత్రలో' ఈ భాషలో అందుబాటులో లేదు.",
        "read_more": "ఇంకా చదవండి"
    }
}

CATEGORY_FEEDS = {
    "World": "http://feeds.bbci.co.uk/news/world/rss.xml",
    "Technology": "http://feeds.bbci.co.uk/news/technology/rss.xml",
    "Business": "http://feeds.bbci.co.uk/news/business/rss.xml",
    "Politics": "http://feeds.bbci.co.uk/news/politics/rss.xml",
    "Health": "http://feeds.bbci.co.uk/news/health/rss.xml",
    "Science": "http://feeds.bbci.co.uk/news/science_and_environment/rss.xml",
    "Entertainment": "http://feeds.bbci.co.uk/news/entertainment_and_arts/rss.xml",
    "Sports": "https://feeds.bbci.co.uk/sport/rss.xml"
}

# --- OpenAI/OpenRouter Client Setup ------------------------------------------

openrouter_api_key = "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" # Load from .env

DEFAULT_AI_MODEL = "mistralai/mistral-7b-instruct" # Recommended general-purpose model for OpenRouter

# --- Initialize OpenAI client for OpenRouter
if not openrouter_api_key:
    st.warning("OpenRouter API Key not found! AI Assistant functionality will be limited.")
    # Initialize with a dummy key and base_url so the app doesn't crash if key is missing.
    # The actual error for missing key will be caught in the try-except block for AI calls.
    client = OpenAI(
        base_url="https://openrouter.ai/api/v1",
        api_key="sk-dummy-key-for-no-ai"
    )
else:
    client = OpenAI(
        base_url="https://openrouter.ai/api/v1",
        api_key=openrouter_api_key
    )

# --- Streamlit Page Configuration --------------------------------------------

st.set_page_config("Timescope", layout="wide")

# Initialize session state for chat history and language
if 'chat_history' not in st.session_state:
    st.session_state['chat_history'] = []
if 'lang_code' not in st.session_state:
    st.session_state['lang_code'] = 'en'


# --- Custom CSS for fixed AI Assistant and general styling -------------------
st.markdown("""
    <style>
    body {
        background-color: #f4f8fc;
    }
    .main {
        color: #003366;
        font-family: 'Segoe UI', sans-serif;
    }
    .stSpinner > div > div {
        border-top-color: #003366;
    }

    /* Adjust padding for the main content to avoid overlap with fixed assistant */
    .st-emotion-cache-z5fcl4 { /* Common class for the main content block (may vary) */
        padding-top: 50px; /* Space from very top */
        padding-bottom: 250px; /* Increased padding for fixed bottom assistant */
    }

    /* Top right controls (language, refresh) */
    .top-right-controls {
        display: flex;
        align-items: center;
        gap: 10px; /* Space between controls */
        justify-content: flex-end; /* Align to the right */
        margin-top: -30px; /* Pull up to align with title */
        margin-right: 20px; /* Padding from right edge */
    }
    .top-right-controls .stButton button {
        background-color: #0056b3;
        color: white;
        border-radius: 50%; /* Make it round */
        width: 40px; /* Fixed width */
        height: 40px; /* Fixed height */
        display: flex;
        align-items: center;
        justify-content: center;
        padding: 0; /* Remove internal padding */
        font-size: 1.2em; /* Icon size */
        box-shadow: 0 2px 5px rgba(0,0,0,0.2);
    }
    .top-right-controls .stButton button:hover {
        background-color: #003366;
    }
    /* Style for language selectbox to appear like a button/icon */
    .top-right-controls .stSelectbox [data-testid="stSelectbox"] {
        width: 60px; /* Adjust width as needed for icon */
    }
    .top-right-controls .stSelectbox [data-testid="stSelectbox"] > div > div {
        background-color: #0056b3;
        color: white;
        border-radius: 50%;
        width: 40px;
        height: 40px;
        display: flex;
        align-items: center;
        justify-content: center;
        padding: 0;
        font-size: 1.2em;
        box-shadow: 0 2px 5px rgba(0,0,0,0.2);
        cursor: pointer;
    }
     .top-right-controls .stSelectbox [data-testid="stSelectbox"] > div > div:hover {
        background-color: #003366;
    }
    .top-right-controls .stSelectbox [data-testid="stSelectbox"] .st-bh { /* Target the displayed value */
        color: white !important; /* Ensure text is white */
        font-size: 1.2em; /* Size for language symbol */
        text-align: center;
        flex-grow: 1; /* Make it take full space */
    }
    .top-right-controls .stSelectbox [data-testid="stSelectbox"] .st-cg { /* Target dropdown arrow */
        color: white !important;
    }

    /* Category Tabs Styling */
    .stTabs [data-testid="stTab"] {
        font-size: 1.1em;
        font-weight: bold;
        color: #003366;
        background-color: #e9f2fb;
        border-radius: 8px 8px 0 0;
        margin-right: 5px;
        padding: 10px 15px;
        border-bottom: 3px solid transparent;
        transition: all 0.2s ease-in-out;
    }
    .stTabs [data-testid="stTab"]:hover {
        background-color: #d6e8f8;
        border-bottom-color: #0056b3;
    }
    .stTabs [data-testid="stTab"][aria-selected="true"] {
        background-color: #0056b3;
        color: white;
        border-bottom-color: #003366;
        box-shadow: 0 -2px 8px rgba(0,0,0,0.1);
    }
    .stTabs [data-testid="stTabGrid"] {
        background-color: #f0f8ff; /* Background for the tab content area */
        border-radius: 0 8px 8px 8px;
        padding: 20px;
        box-shadow: 0 4px 10px rgba(0,0,0,0.05);
    }


    /* Custom CSS for news cards */
    .news-card {
        padding: 15px;
        margin-bottom: 15px; /* Spacing between rows of cards */
        border-radius: 8px;
        /* Gradient background for cards */
        background-image: linear-gradient(to bottom right, #e9f2fb, #d6e8f8);
        border: 1px solid #a7d0f7; /* Subtle border */
        box-shadow: 0 4px 8px rgba(0,0,0,0.1); /* More prominent shadow for cards */
        height: 100%; /* Ensure cards in a row have same height */
        display: flex;
        flex-direction: column;
        justify-content: space-between; /* Pushes content to top, buttons to bottom */
        overflow: hidden; /* Ensures content stays within the card */
    }
    .news-card h4 {
        color: #003366; /* Dark blue title */
        margin-top: 0;
        margin-bottom: 10px;
        font-size: 1.2em; /* Slightly larger title */
    }
    .news-card p {
        color: #333333; /* Darker gray text */
        font-size: 0.9em;
        line-height: 1.5;
        margin-bottom: 15px; /* Space between text and buttons */
        flex-grow: 1; /* Allows text to take available space */
    }
    /* Styling for Streamlit link buttons within cards */
    .news-card a[data-testid="stLinkButton"] { /* Target the Streamlit link button wrapper */
        width: 100%; /* Make link button full width */
        margin-top: 5px; /* Space between elements */
        margin-bottom: 5px; /* Space from bottom of card */
        display: block; /* Ensure it behaves as a block */
    }
    .news-card a[data-testid="stLinkButton"] > div { /* Target the internal div/content of st.link_button */
        width: 100%;
        background-color: #6c757d !important; /* Grey for link button */
        color: white !important;
        border-radius: 5px;
        padding: 8px 12px;
        border: none;
        cursor: pointer;
        text-align: center;
        text-decoration: none !important;
        display: inline-block; /* Keep as inline-block or block as per preference */
    }
    .news-card a[data-testid="stLinkButton"] > div:hover {
        background-color: #5a6268 !important;
    }


    /* CSS for the fixed assistant container (at the bottom) */
    #fixed-assistant-container {
        position: fixed;
        bottom: 0px; /* Position at the bottom */
        left: 0; /* Align with the left edge of the viewport */
        width: 100%;
        background-color: #f4f8fc; /* Match body background */
        /* Fixed padding-left to account for sidebar width (approx 270px for default Streamlit sidebar) */
        padding: 15px 15px 15px 270px;
        box-shadow: 0 -2px 10px rgba(0,0,0,0.1); /* Shadow at the top */
        z-index: 9999;
        box-sizing: border-box; /* Include padding in width calculation */
    }
    /* Style for chat history display within the fixed container */
    #fixed-assistant-container .chat-history-display {
        height: 120px; /* Fixed height for scrollable chat */
        overflow-y: auto; /* Enable scrolling */
        background-color: #e9f2fb;
        border: 1px solid #a7d0f7;
        border-radius: 8px;
        padding: 10px;
        margin-bottom: 10px;
        font-size: 0.9em;
        line-height: 1.4;
    }
    #fixed-assistant-container .chat-history-display p {
        margin-bottom: 5px; /* Space between chat lines */
    }
    #fixed-assistant-container .stTextInput > div > div {
        width: 100%; /* Make the input field take full width of its parent */
    }
    </style>
""", unsafe_allow_html=True)


# --- Language selection in sidebar ---
lang_code = st.session_state.get('lang_code', 'en')  # Ensure lang_code is defined before use
lang_options = [LANGUAGES[lang_code][code] for code in LANGUAGES[lang_code]]
lang_codes = list(LANGUAGES[lang_code].keys())
t = translations[lang_code]  # Define t before using it
selected_lang_display = st.sidebar.selectbox(
    t['language'], # Use translated label
    lang_options,
    index=lang_codes.index(lang_code),
    key="language_select"
)
selected_lang_code = lang_codes[lang_options.index(selected_lang_display)]
if selected_lang_code != lang_code:
    st.session_state['lang_code'] = selected_lang_code
    st.rerun()
lang_code = st.session_state['lang_code']
t = translations[lang_code] # Update translator after potential language change

# --- On This Day Feature -----------------------------------------------------

st.sidebar.header(t['on_this_day'])
selected_date = st.sidebar.date_input(t['pick_date'], datetime.today())

@st.cache_data(ttl=3600) # Cache for 1 hour
def fetch_on_this_day(month, day, lang_code_for_wiki):
    url = f"https://{lang_code_for_wiki}.wikipedia.org/api/rest_v1/feed/onthisday/events/{month}/{day}"
    try:
        res = requests.get(url, timeout=5)
        if res.status_code == 404: # Wikipedia API returns 404 if language is not supported for OnThisDay
            return None
        res.raise_for_status()
        return res.json().get("events", [])
    except requests.exceptions.RequestException as e:
        st.sidebar.error(f"Error fetching historical events: {e}")
        return []
    except Exception as e:
        st.sidebar.error(f"An unexpected error occurred while fetching historical events: {e}")
        return []

supported_onthisday_langs = ['en', 'es', 'fr', 'de', 'ru', 'pt'] # Common languages with OTD pages

if lang_code in supported_onthisday_langs:
    events = fetch_on_this_day(selected_date.month, selected_date.day, lang_code)
else:
    st.sidebar.info(t['unsupported_onthisday'])
    events = fetch_on_this_day(selected_date.month, selected_date.day, 'en') # Fallback to English

if events:
    st.sidebar.subheader(t['events'])
    for ev in events[:6]: # Limit to 6 events for brevity
        event_text = ev['text']
        # Only translate if the fetched language was English and target is different or if fallback to English occurred
        if lang_code != 'en' and (lang_code not in supported_onthisday_langs or lang_code == 'en'):
            try:
                event_text = GoogleTranslator(source='en', target=lang_code).translate(event_text)
            except Exception as e:
                pass # Fallback to original text on error
        st.sidebar.markdown(f"**{ev['year']}** — {event_text}")
        if ev.get("pages"):
            p = ev["pages"][0]
            title = p["titles"]["normalized"]
            url = p["content_urls"]["desktop"]["page"]
            # Only translate if the fetched language was English and target is different or if fallback to English occurred
            if lang_code != 'en' and (lang_code not in supported_onthisday_langs or lang_code == 'en'):
                try:
                    title = GoogleTranslator(source='en', target=lang_code).translate(title)
                except Exception as e:
                    pass # Fallback to original title on error
            st.sidebar.markdown(f"[🔗 {title}]({url})")
else:
    if lang_code in supported_onthisday_langs: # Only show 'no events' if the language is supported
        st.sidebar.info(t['no_events'])


# --- Main App Title and Description ------------------------------------------

st.title(t['title'])
st.markdown(t['description'])
st.markdown("---")

# --- News Fetching and Display Functions -------------------------------------

@st.cache_data(ttl=600) # Cache for 10 minutes
def fetch_rss_entries(url):
    headers = {'User-Agent': 'Mozilla/5.0'}
    try:
        resp = requests.get(url, headers=headers, timeout=10)
        resp.raise_for_status()
        feed = feedparser.parse(resp.content)
        return feed.entries if feed.entries else None
    except Exception as e:
        print("RSS error:", e) # For debugging in console
        return None

def translate_text(text, target_lang):
    if target_lang == 'en':
        return text
    try:
        return GoogleTranslator(source='auto', target=target_lang).translate(text) # Auto-detect source language
    except Exception:
        return text

def get_image_from_entry(entry):
    # Try media:content first
    if hasattr(entry, "media_content"):
        for media in entry.media_content:
            if "url" in media:
                return media["url"]
    # Fallback to looking in links with image type
    if hasattr(entry, "links"):
        for link in entry.links:
            if hasattr(link, "type") and "image" in link.type:
                return link.href
    return None

def clean_html(raw_html):
    if not raw_html:
        return ""
    soup = BeautifulSoup(raw_html, "html.parser")
    return soup.get_text(separator=" ", strip=True)

def display_news_cards_in_two_columns(news_items):
    col1, col2 = st.columns(2)
    card_style = (
        "background-color: #add8e6; border-radius: 10px; padding: 10px; "
        "margin-bottom: 10px; color: #002244; font-family: sans-serif;"
    )
    for i, item in enumerate(news_items):
        with col1 if i % 2 == 0 else col2:
            content = ""
            if item["image"]:
                content += f'<img src="{item["image"]}" style="width:100%; border-radius: 8px; margin-bottom: 0.5em;" />'
            content += f"""<h4 style="margin-bottom: 0.5em;">{item['title']}</h4>"""
            if item["summary"]:
                content += f"""<div style="margin-bottom: 0.5em;">{item["summary"]}</div>"""
            st.markdown(
                f"<div style='{card_style}'>{content}</div>",
                unsafe_allow_html=True
            )
            st.markdown(
                f"[{t['read_more']}]({item['url']})",
                unsafe_allow_html=False
            )

# --- News Display Section ----------------------------------------------------

st.header(t['todays_headlines'])
tabs = st.tabs(list(CATEGORY_FEEDS.keys()))
for tab, (cat, feed_url) in zip(tabs, CATEGORY_FEEDS.items()):
    with tab:
        st.subheader(cat)
        entries = fetch_rss_entries(feed_url)
        if not entries:
            st.error(t['couldnt_load_news'])
        else:
            news_items = []
            for e in entries[:8]: # Limit to 8 articles per category
                title = translate_text(e.title, lang_code)
                summary = getattr(e, "summary", getattr(e, "description", ""))
                summary = clean_html(summary)
                summary = translate_text(summary, lang_code) if summary else ""
                image_url = get_image_from_entry(e)
                news_items.append({
                    "title": title,
                    "summary": summary,
                    "image": image_url,
                    "url": e.link
                })
            display_news_cards_in_two_columns(news_items)

# Refresh button
if st.button(t['refresh_news']):
    st.cache_data.clear() # Clear all caches including RSS feeds
    st.session_state['chat_history'] = [] # Clear AI chat history too
    st.rerun()

# --- AI Assistant Section ----------------------------------------------------

# Fixed position container for the AI assistant
st.markdown("<div id='fixed-assistant-container'>", unsafe_allow_html=True)

st.header(t['ask_ai'])

# Display chat history
with st.container():
    st.markdown("<div class='chat-history-display'>", unsafe_allow_html=True)
    if not st.session_state.chat_history:
        st.markdown("Say hello! I'm your Timescope Assistant, ready to help you explore news and history.")
    for msg in st.session_state.chat_history:
        role_label = "🧑‍💻 You" if msg["role"] == "user" else "🤖 Assistant"
        st.markdown(f"**{role_label}:** {translate_text(msg['content'], lang_code)}") # Translate history too
    st.markdown("</div>", unsafe_allow_html=True)

# Input form for the AI assistant
with st.form("chat_form", clear_on_submit=True):
    user_input = st.text_input(t['ask_placeholder'], 
                               key="assistant_input", 
                               label_visibility="collapsed",
                               placeholder=t['ask_placeholder']) # Use translated placeholder
    send_button = st.form_submit_button("Send")

if send_button and user_input:
    # Add user message to history
    st.session_state.chat_history.append({"role": "user", "content": user_input})
    
    with st.spinner("Thinking..."):
        try:
            # Check if API key is truly available before making the call
            if not openrouter_api_key or openrouter_api_key == "sk-dummy-key-for-no-ai":
                st.error(f"{t['ai_error']} OpenRouter API Key is not set. Please add it to your `.env` file.")
            else:
                # Build the messages list first
                messages = [
                    {"role": "system", "content": translate_text('You are a helpful assistant about world news and history.', lang_code)}
                ] + [
                    {"role": m["role"], "content": m["content"]} for m in st.session_state.chat_history
                ]
                resp = client.chat.completions.create(
                    model=DEFAULT_AI_MODEL, # Use the OpenRouter model
                    messages=messages,
                    max_tokens=1000, # Max tokens to control response length and cost
                )
                assistant_response = resp.choices[0].message.content.strip()
                st.session_state.chat_history.append({"role": "assistant", "content": assistant_response}) # Store original response
                # No need to display directly here, it will be rerendered by st.markdown in history display
            st.rerun() # Rerun to update chat history display
        except Exception as e:
            if isinstance(e, RateLimitError):
                st.error(f"{t['ai_error']} You've hit a rate limit. Please wait a moment and try again.")
                st.error(f"{t['ai_error']} You've hit a rate limit. Please wait a moment and try again.")
            elif isinstance(e, AuthenticationError):
                st.error(f"{t['ai_error']} Authentication failed. Please check your OpenRouter API key in your `.env` file.")
            elif isinstance(e, APIConnectionError):
                st.error(f"{t['ai_error']} Could not connect to the AI service. Please check your internet connection or the OpenRouter API status.")
            elif isinstance(e, APIStatusError):
                # This handles the 402 error for credits as well as other API errors
                st.error(f"{t['ai_error']} An API error occurred: {e.status_code} - {e.response.text if hasattr(e.response, 'text') else str(e)}")
            else:
                st.error(f"{t['ai_error']} An unexpected error occurred: {e}")
            st.session_state.chat_history.append({"role": "assistant", "content": f"Error: {e}"}) # Add error to history
            st.rerun() # Rerun to display error in history

st.markdown("</div>", unsafe_allow_html=True) # Close fixed-assistant-container