import streamlit as st
import boto3
import time
from datetime import datetime
import os

# DynamoDB configuration
DYNAMODB_REGION = os.getenv("DYNAMODB_REGION", "ap-south-1") 
SESSION_TABLE = os.getenv("SESSION_TABLE", "SessionTracking")
COURSE_TABLE = os.getenv("COURSE_TABLE", "CourseTracking")

# AWS Configuration
AWS_ACCESS_KEY_ID = os.getenv("AWS_ACCESS_KEY_ID")
AWS_SECRET_ACCESS_KEY = os.getenv("AWS_SECRET_ACCESS_KEY")

def fetch_courses():
    """Fetch all courses from DynamoDB"""
    try:
        dynamodb = boto3.client(
            "dynamodb",
            region_name=DYNAMODB_REGION,
            aws_access_key_id=AWS_ACCESS_KEY_ID,
            aws_secret_access_key=AWS_SECRET_ACCESS_KEY,
        )
        
        response = dynamodb.scan(TableName=COURSE_TABLE)
        items = response.get("Items", [])
        courses = []
        for item in items:
            course_detail = item.get("course_detail", {}).get("M", {})
            courses.append({
                "course_id": item.get("course_id", {}).get("N"),
                "course_name": item.get("course_name", {}).get("S"),
                "total_videos": item.get("total_videos", {}).get("N", "0"),
                "created_at": item.get("created_at", {}).get("S", "-"),
                "topic_id": course_detail.get("topic_id", {}).get("N", "-"),
                "chapter_id": course_detail.get("chapter_id", {}).get("N", "-"),
            })
        return courses
    except Exception as e:
        st.error(f"⚠️ Error fetching courses: {e}")
        return []

def fetch_sessions():
    """Fetch all sessions from DynamoDB"""
    try:
        dynamodb = boto3.client(
            "dynamodb",
            region_name=DYNAMODB_REGION,
            aws_access_key_id=AWS_ACCESS_KEY_ID,
            aws_secret_access_key=AWS_SECRET_ACCESS_KEY,
        )
        
        response = dynamodb.scan(TableName=SESSION_TABLE)
        items = response.get("Items", [])
        sessions = []
        for item in items:
            sessions.append({
                "session_id": item.get("session_id", {}).get("S"),
                "course_id": item.get("course_id", {}).get("N"),
                "topic_id": item.get("topic_id", {}).get("N"),
                "topic_title": item.get("topic_title", {}).get("S", "-"),
                "status": item.get("status", {}).get("S", "unknown"),
                "node": item.get("node", {}).get("S", "-"),
                "created_at": item.get("created_at", {}).get("S", "-"),
                "updated_at": item.get("updated_at", {}).get("S", "-"),
                "video_url": item.get("video_url", {}).get("S", None),
            })
        return sessions
    except Exception as e:
        st.error(f"⚠️ Error fetching sessions: {e}")
        return []

def get_sessions_by_course(course_id):
    """Get sessions for a specific course"""
    all_sessions = fetch_sessions()
    return [session for session in all_sessions if session['course_id'] == str(course_id)]

def render_admin_dashboard():
    """Render the admin dashboard page"""
    st.markdown("<h1 style='color:#4F97FF;text-align:center;'>📊 Admin Dashboard</h1>", unsafe_allow_html=True)
    
    # Auto-refresh controls
    col1, col2, col3 = st.columns([1, 1, 2])
    with col1:
        if st.button("🔄 Refresh Now", key="manual_refresh"):
            st.rerun()
    
    with col2:
        auto_refresh = st.toggle("Auto Refresh (30s)", value=False)
    
    # Tabs for different views
    tab1, tab2, tab3 = st.tabs(["📚 Courses Overview", "🎬 Sessions Overview", "📈 Course Details"])
    
    with tab1:
        render_courses_overview()
    
    with tab2:
        render_sessions_overview()
        
    with tab3:
        render_course_details()
    
    # Auto-refresh mechanism
    if auto_refresh:
        time.sleep(30)
        st.rerun()

def render_courses_overview():
    """Render courses overview tab"""
    st.markdown("### 📚 All Courses")
    
    courses = fetch_courses()
    
    if not courses:
        st.warning("No courses found yet.")
        st.info("Courses will appear here once you create them from the Course Generation page.")
        return
    
    # Display course count
    st.markdown(f"**Total Courses: {len(courses)}**")
    
    # Sort courses by created_at (newest first)
    try:
        courses.sort(key=lambda x: x['created_at'] if x['created_at'] != '-' else '1970-01-01', reverse=True)
    except:
        pass
    
    # Display courses in cards
    for i, course in enumerate(courses):
        with st.container():
            st.markdown(f"""
            <div style="background:#2D2D2D;padding:1.5rem;border-radius:12px;margin-bottom:1rem;border:1px solid #444;">
                <div style="display:flex;justify-content:space-between;align-items:center;margin-bottom:1rem;">
                    <h4 style="color:#4F97FF;margin:0;">📚 {course['course_name']}</h4>
                    <span style="background:#10B981;color:black;padding:0.3rem 0.8rem;border-radius:15px;font-size:0.8rem;font-weight:bold;">COURSE ID: {course['course_id']}</span>
                </div>
                <div style="display:grid;grid-template-columns:1fr 1fr 1fr;gap:1rem;">
                    <div>
                        <b>📹 Total Videos:</b><br><span style="color:#E0E0E0;">{course['total_videos']}</span>
                    </div>
                    <div>
                        <b>🎯 Topic ID:</b><br><span style="color:#E0E0E0;">{course['topic_id']}</span>
                    </div>
                    <div>
                        <b>📖 Chapter ID:</b><br><span style="color:#E0E0E0;">{course['chapter_id']}</span>
                    </div>
                </div>
                <div style="margin-top:1rem;">
                    <b>📅 Created:</b> <span style="color:#888;">{course['created_at'][:19] if course['created_at'] != '-' else '-'}</span>
                </div>
            </div>
            """, unsafe_allow_html=True)

def render_sessions_overview():
    """Render sessions overview tab"""
    st.markdown("### 🎬 All Sessions")
    
    sessions = fetch_sessions()
    
    if not sessions:
        st.warning("No sessions found yet.")
        st.info("Sessions will appear here once you start generating courses.")
        return
    
    # Display session count and status summary
    col1, col2, col3, col4 = st.columns(4)
    
    status_counts = {}
    for session in sessions:
        status = session['status'].lower()
        status_counts[status] = status_counts.get(status, 0) + 1
    
    with col1:
        st.metric("📊 Total Sessions", len(sessions))
    with col2:
        completed = status_counts.get('completed', 0)
        st.metric("✅ Completed", completed)
    with col3:
        processing = status_counts.get('processing', 0) + status_counts.get('in_progress', 0) + status_counts.get('running', 0)
        st.metric("⏳ Processing", processing)
    with col4:
        failed = status_counts.get('failed', 0) + status_counts.get('error', 0)
        st.metric("❌ Failed", failed)
    
    # Sort sessions by updated_at (newest first)
    try:
        sessions.sort(key=lambda x: x['updated_at'] if x['updated_at'] != '-' else '1970-01-01', reverse=True)
    except:
        pass
    
    # Display sessions
    for i, session in enumerate(sessions):
        status_color = {
            'completed': '#10B981',
            'processing': '#F59E0B',
            'in_progress': '#F59E0B', 
            'running': '#F59E0B',
            'failed': '#EF4444',
            'error': '#EF4444'
        }.get(session['status'].lower(), '#6B7280')
        
        with st.container():
            st.markdown(f"""
            <div style="background:#2D2D2D;padding:1.5rem;border-radius:12px;margin-bottom:1rem;border:1px solid #444;">
                <div style="display:flex;justify-content:space-between;align-items:center;margin-bottom:1rem;">
                    <h4 style="color:#4F97FF;margin:0;">🎬 {session['topic_title']}</h4>
                    <span style="background:{status_color};color:white;padding:0.3rem 0.8rem;border-radius:15px;font-size:0.8rem;font-weight:bold;">{session['status'].upper()}</span>
                </div>
                <div style="display:grid;grid-template-columns:1fr 1fr 1fr;gap:1rem;">
                    <div>
                        <b>🆔 Session ID:</b><br><code style="background:#1A1A1A;padding:0.2rem;border-radius:4px;font-size:0.8rem;">{session['session_id'][:20]}...</code>
                    </div>
                    <div>
                        <b>📚 Course ID:</b><br><span style="color:#E0E0E0;">{session['course_id']}</span>
                    </div>
                    <div>
                        <b>🎯 Topic ID:</b><br><span style="color:#E0E0E0;">{session['topic_id']}</span>
                    </div>
                </div>
                <div style="margin-top:1rem;display:flex;justify-content:space-between;">
                    <div><b>🔧 Current Node:</b> <span style="color:#E0E0E0;">{session['node']}</span></div>
                    <div><b>⏱️ Updated:</b> <span style="color:#888;">{session['updated_at'][:19] if session['updated_at'] != '-' else '-'}</span></div>
                </div>
                {f"<div style='margin-top:1rem;'><b>🎥 Video:</b> <a href='{session['video_url']}' target='_blank' style='color:#4F97FF;'>📺 Watch Video</a></div>" if session['video_url'] else ""}
            </div>
            """, unsafe_allow_html=True)

def render_course_details():
    """Render detailed course view with sessions"""
    st.markdown("### 📈 Detailed Course View")
    
    courses = fetch_courses()
    
    if not courses:
        st.warning("No courses found.")
        return
    
    # Course selection
    course_options = {f"{course['course_name']} (ID: {course['course_id']})": course['course_id'] for course in courses}
    
    if course_options:
        selected_course_display = st.selectbox(
            "Select a course to view details:",
            options=list(course_options.keys()),
            key="course_detail_selector"
        )
        
        selected_course_id = course_options[selected_course_display]
        selected_course = next(course for course in courses if course['course_id'] == str(selected_course_id))
        
        # Display course information
        st.markdown(f"""
        <div style="background:#2D2D2D;padding:2rem;border-radius:12px;margin-bottom:2rem;border:1px solid #444;">
            <h3 style="color:#4F97FF;margin-bottom:1rem;">📚 {selected_course['course_name']}</h3>
            <div style="display:grid;grid-template-columns:1fr 1fr 1fr;gap:1rem;">
                <div><b>🆔 Course ID:</b> {selected_course['course_id']}</div>
                <div><b>📹 Total Videos:</b> {selected_course['total_videos']}</div>
                <div><b>📅 Created:</b> {selected_course['created_at'][:19] if selected_course['created_at'] != '-' else '-'}</div>
            </div>
        </div>
        """, unsafe_allow_html=True)
        
        # Get sessions for this course
        course_sessions = get_sessions_by_course(selected_course_id)
        
        if course_sessions:
            st.markdown(f"#### 🎬 Sessions for this Course ({len(course_sessions)} sessions)")
            
            # Session status summary for this course
            col1, col2, col3 = st.columns(3)
            course_status_counts = {}
            for session in course_sessions:
                status = session['status'].lower()
                course_status_counts[status] = course_status_counts.get(status, 0) + 1
            
            with col1:
                completed = course_status_counts.get('completed', 0)
                st.metric("✅ Completed", completed)
            with col2:
                processing = course_status_counts.get('processing', 0) + course_status_counts.get('in_progress', 0) + course_status_counts.get('running', 0)
                st.metric("⏳ Processing", processing)
            with col3:
                failed = course_status_counts.get('failed', 0) + course_status_counts.get('error', 0)
                st.metric("❌ Failed", failed)
            
            # Display sessions in a table format
            for session in course_sessions:
                status_color = {
                    'completed': '#10B981',
                    'processing': '#F59E0B',
                    'in_progress': '#F59E0B', 
                    'running': '#F59E0B',
                    'failed': '#EF4444',
                    'error': '#EF4444'
                }.get(session['status'].lower(), '#6B7280')
                
                st.markdown(f"""
                <div style="background:#1E1E1E;padding:1rem;border-radius:8px;margin-bottom:0.5rem;border-left:4px solid {status_color};">
                    <div style="display:flex;justify-content:between;align-items:center;">
                        <div style="flex:2;"><b>{session['topic_title']}</b></div>
                        <div style="flex:1;text-align:center;"><span style="background:{status_color};color:white;padding:0.2rem 0.6rem;border-radius:10px;font-size:0.75rem;">{session['status'].upper()}</span></div>
                        <div style="flex:1;text-align:right;color:#888;font-size:0.8rem;">{session['node']}</div>
                    </div>
                    {f"<div style='margin-top:0.5rem;'><a href='{session['video_url']}' target='_blank' style='color:#4F97FF;font-size:0.8rem;'>🎥 Watch Video</a></div>" if session['video_url'] else ""}
                </div>
                """, unsafe_allow_html=True)
        else:
            st.info("No sessions found for this course yet.")