from flask import Blueprint, render_template, request, flash, redirect, url_for, jsonify, current_app
from flask_login import login_required, current_user
from functools import wraps
from datetime import datetime, timedelta
from sqlalchemy import func, desc
from app.extensions import db
from app.models import User, Post, PostImage, GPXFile, Comment, Like, PageView

admin = Blueprint('admin', __name__, url_prefix='/admin')

def admin_required(f):
    """Decorator to require admin access"""
    @wraps(f)
    def decorated_function(*args, **kwargs):
        if not current_user.is_authenticated or not current_user.is_admin:
            flash('Admin access required.', 'error')
            return redirect(url_for('auth.login'))
        return f(*args, **kwargs)
    return decorated_function

@admin.route('/')
@login_required
@admin_required
def dashboard():
    """Admin dashboard with site statistics"""
    # Get basic statistics
    total_users = User.query.count()
    total_posts = Post.query.count()
    published_posts = Post.query.filter_by(published=True).count()
    pending_posts = Post.query.filter_by(published=False).count()
    total_comments = Comment.query.count()
    total_likes = Like.query.count()
    
    # Active users (users who created posts or comments in the last 30 days)
    thirty_days_ago = datetime.utcnow() - timedelta(days=30)
    active_users = db.session.query(User.id).filter(
        db.or_(
            User.posts.any(Post.created_at >= thirty_days_ago),
            User.comments.any(Comment.created_at >= thirty_days_ago)
        )
    ).distinct().count()
    
    # Recent activity
    recent_posts = Post.query.order_by(Post.created_at.desc()).limit(5).all()
    recent_users = User.query.order_by(User.created_at.desc()).limit(5).all()
    
    # Page views statistics
    today = datetime.utcnow().date()
    yesterday = today - timedelta(days=1)
    week_ago = today - timedelta(days=7)
    
    views_today = PageView.query.filter(
        func.date(PageView.created_at) == today
    ).count()
    
    views_yesterday = PageView.query.filter(
        func.date(PageView.created_at) == yesterday
    ).count()
    
    views_this_week = PageView.query.filter(
        PageView.created_at >= week_ago
    ).count()
    
    # Most viewed posts
    most_viewed_posts = db.session.query(
        Post.id, Post.title, func.count(PageView.id).label('view_count')
    ).join(PageView, Post.id == PageView.post_id)\
     .group_by(Post.id, Post.title)\
     .order_by(desc('view_count'))\
     .limit(10).all()
    
    # Most viewed pages
    most_viewed_pages = db.session.query(
        PageView.path, func.count(PageView.id).label('view_count')
    ).group_by(PageView.path)\
     .order_by(desc('view_count'))\
     .limit(10).all()
    
    return render_template('admin/dashboard.html',
                         total_users=total_users,
                         total_posts=total_posts,
                         published_posts=published_posts,
                         pending_posts=pending_posts,
                         total_comments=total_comments,
                         total_likes=total_likes,
                         active_users=active_users,
                         recent_posts=recent_posts,
                         recent_users=recent_users,
                         views_today=views_today,
                         views_yesterday=views_yesterday,
                         views_this_week=views_this_week,
                         most_viewed_posts=most_viewed_posts,
                         most_viewed_pages=most_viewed_pages)

@admin.route('/posts')
@login_required
@admin_required
def posts():
    """Admin post management - review posts"""
    page = request.args.get('page', 1, type=int)
    status = request.args.get('status', 'pending')  # pending, published, all
    
    query = Post.query
    
    if status == 'pending':
        query = query.filter_by(published=False)
    elif status == 'published':
        query = query.filter_by(published=True)
    # 'all' shows all posts
    
    posts = query.order_by(Post.created_at.desc()).paginate(
        page=page, per_page=20, error_out=False
    )
    
    return render_template('admin/posts.html', posts=posts, status=status)

@admin.route('/posts/<int:post_id>')
@login_required
@admin_required
def post_detail(post_id):
    """View post details for review"""
    post = Post.query.get_or_404(post_id)
    return render_template('admin/post_detail.html', post=post)

@admin.route('/posts/<int:post_id>/publish', methods=['POST'])
@login_required
@admin_required
def publish_post(post_id):
    """Publish a post and create map routes if GPX files exist"""
    post = Post.query.get_or_404(post_id)
    post.published = True
    post.updated_at = datetime.utcnow()
    
    try:
        db.session.commit()
        
        # Create map routes for GPX files when post is published
        from app.utils.gpx_processor import process_post_approval
        success = process_post_approval(post_id)
        
        if success:
            flash(f'Post "{post.title}" has been published and map routes created.', 'success')
        else:
            flash(f'Post "{post.title}" has been published. No GPX files found or error creating map routes.', 'warning')
        
    except Exception as e:
        db.session.rollback()
        current_app.logger.error(f'Error publishing post {post_id}: {str(e)}')
        flash(f'Error publishing post: {str(e)}', 'error')
    
    return redirect(url_for('admin.posts'))

@admin.route('/posts/<int:post_id>/unpublish', methods=['POST'])
@login_required
@admin_required
def unpublish_post(post_id):
    """Unpublish a post and remove from map"""
    post = Post.query.get_or_404(post_id)
    post.published = False
    post.updated_at = datetime.utcnow()
    
    try:
        # Note: We keep the MapRoute data for potential re-publishing
        # Only the API will filter by published status
        db.session.commit()
        flash(f'Post "{post.title}" has been unpublished.', 'success')
        
    except Exception as e:
        db.session.rollback()
        current_app.logger.error(f'Error unpublishing post {post_id}: {str(e)}')
        flash(f'Error unpublishing post: {str(e)}', 'error')
    
    return redirect(url_for('admin.posts'))

@admin.route('/posts/<int:post_id>/delete', methods=['POST'])
@login_required
@admin_required
def delete_post(post_id):
    """Delete a post"""
    current_app.logger.info(f'Admin {current_user.id} attempting to delete post {post_id}')
    
    # Get all posts before deletion for debugging
    all_posts_before = Post.query.all()
    current_app.logger.info(f'Posts before deletion: {[p.id for p in all_posts_before]}')
    
    post = Post.query.get_or_404(post_id)
    title = post.title
    
    current_app.logger.info(f'Found post to delete: ID={post.id}, Title="{title}"')
    
    try:
        # Delete associated files and records
        db.session.delete(post)
        db.session.commit()

        # Clean up orphaned media folders
        from app.utils.clean_orphan_media import clean_orphan_post_media
        clean_orphan_post_media()

        # Check posts after deletion
        all_posts_after = Post.query.all()
        current_app.logger.info(f'Posts after deletion: {[p.id for p in all_posts_after]}')

        current_app.logger.info(f'Successfully deleted post {post_id}: "{title}"')
        flash(f'Post "{title}" has been deleted.', 'success')

    except Exception as e:
        db.session.rollback()
        current_app.logger.error(f'Error deleting post {post_id}: {str(e)}')
        flash(f'Error deleting post: {str(e)}', 'error')

    return redirect(url_for('admin.posts'))

@admin.route('/users')
@login_required
@admin_required
def users():
    """Admin user management"""
    page = request.args.get('page', 1, type=int)
    
    users = User.query.order_by(User.created_at.desc()).paginate(
        page=page, per_page=50, error_out=False
    )
    
    return render_template('admin/users.html', users=users)

@admin.route('/users/<int:user_id>')
@login_required
@admin_required
def user_detail(user_id):
    """View user details"""
    user = User.query.get_or_404(user_id)
    user_posts = Post.query.filter_by(author_id=user_id).order_by(Post.created_at.desc()).all()
    user_comments = Comment.query.filter_by(author_id=user_id).order_by(Comment.created_at.desc()).all()
    
    return render_template('admin/user_detail.html', 
                         user=user, 
                         user_posts=user_posts, 
                         user_comments=user_comments)

@admin.route('/users/<int:user_id>/toggle-status', methods=['POST'])
@login_required
@admin_required
def toggle_user_status(user_id):
    """Toggle user active/inactive status"""
    user = User.query.get_or_404(user_id)
    
    # Prevent self-modification if current user is admin
    if user.is_admin and user.id == current_user.id:
        return jsonify({'success': False, 'error': 'Cannot deactivate your own admin account'})
    
    # Toggle status
    user.is_active = not user.is_active
    status = "activated" if user.is_active else "deactivated"
    
    try:
        db.session.commit()
        return jsonify({
            'success': True, 
            'message': f'User {user.nickname} has been {status}',
            'is_active': user.is_active
        })
    except Exception as e:
        db.session.rollback()
        return jsonify({'success': False, 'error': f'Failed to update user status: {str(e)}'})

@admin.route('/users/<int:user_id>/delete', methods=['DELETE', 'POST'])
@login_required
@admin_required
def delete_user(user_id):
    """Delete user and transfer their posts to admin"""
    user = User.query.get_or_404(user_id)
    
    # Prevent self-deletion
    if user.id == current_user.id:
        return jsonify({'success': False, 'error': 'Cannot delete your own account'})
    
    # Prevent deletion of other admins
    if user.is_admin:
        return jsonify({'success': False, 'error': 'Cannot delete admin accounts'})
    
    try:
        # Transfer all user's posts to current admin
        user_posts = Post.query.filter_by(author_id=user.id).all()
        for post in user_posts:
            post.author_id = current_user.id
        
        # Transfer all user's comments to current admin
        user_comments = Comment.query.filter_by(author_id=user.id).all()
        for comment in user_comments:
            comment.author_id = current_user.id
        
        # Delete user's likes (they will be orphaned)
        Like.query.filter_by(user_id=user.id).delete()
        
        # Delete user's page views
        PageView.query.filter_by(user_id=user.id).delete()
        
        username = user.nickname
        user_posts_count = len(user_posts)
        
        # Delete the user
        db.session.delete(user)
        db.session.commit()
        
        return jsonify({
            'success': True, 
            'message': f'User {username} has been deleted. {user_posts_count} posts transferred to {current_user.nickname}.'
        })
        
    except Exception as e:
        db.session.rollback()
        return jsonify({'success': False, 'error': f'Failed to delete user: {str(e)}'})

@admin.route('/analytics')
@login_required
@admin_required
def analytics():
    """Detailed analytics page"""
    # Get date range from query params
    days = request.args.get('days', 30, type=int)
    end_date = datetime.utcnow().date()
    start_date = end_date - timedelta(days=days)
    
    # Daily views for the chart
    daily_views = db.session.query(
        func.date(PageView.created_at).label('date'),
        func.count(PageView.id).label('views')
    ).filter(
        func.date(PageView.created_at) >= start_date
    ).group_by(func.date(PageView.created_at))\
     .order_by('date').all()
    
    # Top posts by views
    top_posts = db.session.query(
        Post.id, Post.title, Post.author, func.count(PageView.id).label('view_count')
    ).join(PageView, Post.id == PageView.post_id)\
     .filter(PageView.created_at >= start_date)\
     .group_by(Post.id, Post.title)\
     .order_by(desc('view_count'))\
     .limit(20).all()
    
    # User activity - separate queries to avoid cartesian product
    user_posts = db.session.query(
        User.id,
        User.nickname, 
        func.count(Post.id).label('post_count')
    ).outerjoin(Post, User.id == Post.author_id)\
     .group_by(User.id, User.nickname).subquery()
    
    user_comments = db.session.query(
        User.id,
        func.count(Comment.id).label('comment_count')
    ).outerjoin(Comment, User.id == Comment.author_id)\
     .group_by(User.id).subquery()
    
    user_activity = db.session.query(
        user_posts.c.nickname,
        user_posts.c.post_count,
        func.coalesce(user_comments.c.comment_count, 0).label('comment_count')
    ).outerjoin(user_comments, user_posts.c.id == user_comments.c.id)\
     .order_by(desc(user_posts.c.post_count))\
     .limit(20).all()
    
    # Get overall statistics
    total_views = PageView.query.count()
    unique_visitors = db.session.query(PageView.ip_address).distinct().count()
    today_views = PageView.query.filter(
        func.date(PageView.created_at) == datetime.utcnow().date()
    ).count()
    week_start = datetime.utcnow().date() - timedelta(days=7)
    week_views = PageView.query.filter(
        func.date(PageView.created_at) >= week_start
    ).count()
    
    # Popular pages
    popular_pages = db.session.query(
        PageView.path,
        func.count(PageView.id).label('view_count')
    ).group_by(PageView.path)\
     .order_by(desc('view_count'))\
     .limit(10).all()
    
    # Recent activity
    recent_views = PageView.query.join(User, PageView.user_id == User.id, isouter=True)\
                         .order_by(desc(PageView.created_at))\
                         .limit(20).all()
    
    # Browser statistics (extract from user agent)
    browser_stats = db.session.query(
        func.substr(PageView.user_agent, 1, 50).label('browser'),
        func.count(PageView.id).label('view_count')
    ).filter(PageView.user_agent.isnot(None))\
     .group_by(func.substr(PageView.user_agent, 1, 50))\
     .order_by(desc('view_count'))\
     .limit(10).all()
    
    return render_template('admin/analytics.html',
                         total_views=total_views,
                         unique_visitors=unique_visitors,
                         today_views=today_views,
                         week_views=week_views,
                         popular_pages=popular_pages,
                         recent_views=recent_views,
                         browser_stats=browser_stats,
                         daily_views=daily_views,
                         top_posts=top_posts,
                         user_activity=user_activity,
                         days=days)

# API endpoints for AJAX requests
@admin.route('/api/quick-stats')
@login_required
@admin_required
def api_quick_stats():
    """Quick stats for dashboard widgets"""
    pending_count = Post.query.filter_by(published=False).count()
    today_views = PageView.query.filter(
        func.date(PageView.created_at) == datetime.utcnow().date()
    ).count()
    
    return jsonify({
        'pending_posts': pending_count,
        'today_views': today_views
    })