from flask import Blueprint, render_template, request, redirect, url_for, flash, jsonify
from flask_login import login_required, current_user
from models import db, Product, Node, NodeImage, User, SiteConfig
from functools import wraps
import json
import os
from werkzeug.utils import secure_filename

admin_bp = Blueprint('admin', __name__)

# Add these configurations to your app
UPLOAD_FOLDER = 'static/uploads'
ALLOWED_EXTENSIONS = {'png', 'jpg', 'jpeg', 'gif'}

def admin_required(f):
    @wraps(f)
    def decorated_function(*args, **kwargs):
        if not current_user.is_authenticated or not current_user.is_admin:
            flash('You need admin privileges to access this page.', 'danger')
            return redirect(url_for('auth.login'))
        return f(*args, **kwargs)
    return decorated_function

@admin_bp.route('/')
@login_required
@admin_required
def admin_dashboard():
    products = Product.query.all()
    return render_template('admin/admin_dashboard.html', products=products)

@admin_bp.route('/create_product', methods=['GET', 'POST'])
@login_required
@admin_required
def create_product():
    if request.method == 'POST':
        title = request.form.get('title')
        thumbnail = request.form.get('thumbnail')
        description = request.form.get('description', '')
        
        # Get the root question and content from the form
        root_question = request.form.get('root_question', 'How can we help you?')
        root_content = request.form.get('root_content', 'Welcome to the decision tree.')
        
        # Create a default root node for the decision tree
        root_node = Node(question=root_question, content=root_content)
        db.session.add(root_node)
        db.session.commit()
        
        # Create the product with the root node
        product = Product(
            title=title, 
            thumbnail=thumbnail, 
            description=description,
            root_node_id=root_node.id
        )
        db.session.add(product)
        db.session.commit()
        
        flash("Product created successfully! Now you can build the decision tree.", "success")
        return redirect(url_for('admin.edit_decision_tree', product_id=product.id))
    
    return render_template('admin/create_product.html')

@admin_bp.route('/edit_product/<int:product_id>', methods=['GET', 'POST'])
@login_required
@admin_required
def edit_product(product_id):
    product = Product.query.get_or_404(product_id)
    
    if request.method == 'POST':
        product.title = request.form.get('title')
        product.thumbnail = request.form.get('thumbnail')
        product.description = request.form.get('description', '')
        
        db.session.commit()
        flash("Product updated successfully!", "success")
        return redirect(url_for('admin.admin_dashboard'))
    
    return render_template('admin/edit_product.html', product=product)

@admin_bp.route('/delete_product/<int:product_id>')
@login_required
@admin_required
def delete_product(product_id):
    product = Product.query.get_or_404(product_id)
    
    # Delete the root node and all associated nodes (this would need a more sophisticated
    # implementation to delete the entire tree)
    if product.root_node:
        db.session.delete(product.root_node)
    
    db.session.delete(product)
    db.session.commit()
    
    flash("Product deleted successfully!", "success")
    return redirect(url_for('admin.admin_dashboard'))

@admin_bp.route('/edit_decision_tree/<int:product_id>')
@login_required
@admin_required
def edit_decision_tree(product_id):
    product = Product.query.get_or_404(product_id)
    
    # Generate tree data for visualization
    tree_data = generate_tree_data(product.root_node, current_node_id=None)
    tree_json = json.dumps(tree_data)
    
    return render_template('admin/edit_decision_tree.html', product=product, tree_json=tree_json)

@admin_bp.route('/node/<int:node_id>', methods=['GET', 'POST'])
@login_required
@admin_required
def edit_node(node_id):
    node = Node.query.get_or_404(node_id)
    
    # Find which product this node belongs to
    product = find_product_for_node(node)
    
    if request.method == 'POST':
        node.question = request.form.get('question')
        node.content = request.form.get('content')
        node.is_terminal = 'is_terminal' in request.form
        
        # Handle YouTube URL
        youtube_url = request.form.get('youtube_url')
        if youtube_url:
            node.youtube_url = youtube_url
        elif node.youtube_url and not youtube_url:
            # Clear the YouTube URL if the field is empty
            node.youtube_url = None
        
        # Handle image upload
        if 'image_upload' in request.files:
            file = request.files['image_upload']
            if file and file.filename and allowed_file(file.filename):
                # Create upload directory if it doesn't exist
                os.makedirs(UPLOAD_FOLDER, exist_ok=True)
                
                # Generate a secure filename with node ID to avoid conflicts
                filename = secure_filename(f"node_{node.id}_{file.filename}")
                filepath = os.path.join(UPLOAD_FOLDER, filename)
                
                # Save the file
                file.save(filepath)
                
                # Create a new NodeImage
                caption = request.form.get('image_caption', '')
                
                # Get the highest display order
                max_order = db.session.query(db.func.max(NodeImage.display_order)).filter(NodeImage.node_id == node.id).scalar() or 0
                
                # Create new image with next order
                new_image = NodeImage(
                    node_id=node.id,
                    image_url=f"/{filepath}",
                    caption=caption,
                    display_order=max_order + 1
                )
                db.session.add(new_image)
        
        # Handle image removal
        for key in request.form:
            if key.startswith('remove_image_'):
                try:
                    image_id = int(key.split('_')[-1])
                    image = NodeImage.query.get(image_id)
                    if image and image.node_id == node.id:
                        # Delete the file if it exists
                        if image.image_url and os.path.exists(image.image_url.lstrip('/')):
                            os.remove(image.image_url.lstrip('/'))
                        
                        # Delete the database record
                        db.session.delete(image)
                except (ValueError, AttributeError):
                    pass
        
        # Handle image reordering
        for key in request.form:
            if key.startswith('image_order_'):
                try:
                    image_id = int(key.split('_')[-1])
                    new_order = int(request.form[key])
                    image = NodeImage.query.get(image_id)
                    if image and image.node_id == node.id:
                        image.display_order = new_order
                except (ValueError, AttributeError):
                    pass
        
        db.session.commit()
        flash("Node updated successfully!", "success")
        
        return redirect(url_for('admin.edit_node', node_id=node.id))
    
    # Generate tree data for visualization
    if product:
        tree_data = generate_tree_data(product.root_node, current_node_id=node.id)
        tree_json = json.dumps(tree_data)
    else:
        tree_json = '{}'
    
    return render_template('admin/edit_node.html', node=node, product=product, tree_json=tree_json)

# Helper function to find which product a node belongs to
def find_product_for_node(node):
    # First check if this is a root node
    product = Product.query.filter_by(root_node_id=node.id).first()
    
    if not product:
        # Try to find the product by traversing up the tree
        for p in Product.query.all():
            root_node = p.root_node
            if root_node:
                # Check if node is in the tree
                if is_node_in_tree(root_node, node.id):
                    product = p
                    break
    
    return product

# Helper function to check if a node is in a tree
def is_node_in_tree(root, node_id):
    if not root:
        return False
    
    if root.id == node_id:
        return True
    
    # Check yes branch
    if root.yes_node_id and is_node_in_tree(root.yes_node, node_id):
        return True
    
    # Check no branch
    if root.no_node_id and is_node_in_tree(root.no_node, node_id):
        return True
    
    return False

# Helper function to generate tree data for D3.js visualization
def generate_tree_data(node, current_node_id=None):
    if not node:
        return None
    
    # Create the node data
    node_data = {
        'name': node.question[:30] + ('...' if len(node.question) > 30 else ''),
        'id': node.id,
        'current': node.id == current_node_id,
        'type': 'root',  # Default type
        'is_terminal': node.is_terminal,  # Make sure this property is included
        'children': []
    }
    
    # Add yes branch
    if node.yes_node:
        yes_data = generate_tree_data(node.yes_node, current_node_id)
        yes_data['type'] = 'yes'
        node_data['children'].append(yes_data)
    
    # Add no branch
    if node.no_node:
        no_data = generate_tree_data(node.no_node, current_node_id)
        no_data['type'] = 'no'
        node_data['children'].append(no_data)
    
    return node_data

@admin_bp.route('/add_child_node/<int:parent_id>/<string:direction>', methods=['POST'])
@login_required
@admin_required
def add_child_node(parent_id, direction):
    parent = Node.query.get_or_404(parent_id)
    
    # Create a new node
    new_node = Node(
        question=request.form.get('question', 'New Question'),
        content=request.form.get('content', 'New Content')
    )
    db.session.add(new_node)
    db.session.commit()
    
    # Link the new node to the parent
    if direction == 'yes':
        parent.yes_node_id = new_node.id
    else:
        parent.no_node_id = new_node.id
    
    db.session.commit()
    
    # Find which product this node belongs to
    product = None
    # First check if this is a root node
    product = Product.query.filter_by(root_node_id=parent.id).first()
    
    if not product:
        # Try to find the product by traversing up the tree
        # This is a simplified approach and might not work for complex trees
        for p in Product.query.all():
            root_node = p.root_node
            if root_node:
                # Check if parent is in the yes branch
                current = root_node
                while current and current.yes_node_id:
                    if current.yes_node_id == parent.id:
                        product = p
                        break
                    current = current.yes_node
                
                # Check if parent is in the no branch
                current = root_node
                while current and current.no_node_id:
                    if current.no_node_id == parent.id:
                        product = p
                        break
                    current = current.no_node
    
    flash("Node added successfully!", "success")
    
    # Redirect to edit the new node instead of going back to the dashboard
    return redirect(url_for('admin.edit_node', node_id=new_node.id))

# Helper function to check if file extension is allowed
def allowed_file(filename):
    return '.' in filename and \
           filename.rsplit('.', 1)[1].lower() in ALLOWED_EXTENSIONS

@admin_bp.route('/run_migrations')
@login_required
@admin_required
def run_migrations():
    """Run database migrations"""
    try:
        # Check if columns already exist using the new SQLAlchemy 2.0 API
        with db.engine.connect() as conn:
            result = conn.execute(db.text("PRAGMA table_info(node)"))
            columns = result.fetchall()
            column_names = [col[1] for col in columns]
            
            # Add image_url column if it doesn't exist
            if 'image_url' not in column_names:
                conn.execute(db.text("ALTER TABLE node ADD COLUMN image_url VARCHAR(500)"))
                flash("Added image_url column to Node table", "success")
            
            # Add youtube_url column if it doesn't exist
            if 'youtube_url' not in column_names:
                conn.execute(db.text("ALTER TABLE node ADD COLUMN youtube_url VARCHAR(500)"))
                flash("Added youtube_url column to Node table", "success")
            
            conn.commit()
        
        flash("Database migration completed successfully", "success")
    except Exception as e:
        flash(f"Error during migration: {str(e)}", "danger")
    
    return redirect(url_for('admin.admin_dashboard'))

@admin_bp.route('/users')
@login_required
@admin_required
def manage_users():
    users = User.query.all()
    registration_enabled = SiteConfig.get_setting('registration_enabled', 'true') == 'true'
    return render_template('admin/manage_users.html', users=users, registration_enabled=registration_enabled)

@admin_bp.route('/users/toggle_registration')
@login_required
@admin_required
def toggle_registration():
    current_setting = SiteConfig.get_setting('registration_enabled', 'true')
    new_setting = 'false' if current_setting == 'true' else 'true'
    SiteConfig.set_setting('registration_enabled', new_setting, 'Controls whether user registration is enabled')
    
    status = "enabled" if new_setting == 'true' else "disabled"
    flash(f"User registration has been {status}", "success")
    return redirect(url_for('admin.manage_users'))

@admin_bp.route('/users/<int:user_id>/toggle_admin')
@login_required
@admin_required
def toggle_admin(user_id):
    user = User.query.get_or_404(user_id)
    
    # Prevent removing admin status from the last admin
    if user.is_admin and User.query.filter_by(is_admin=True).count() <= 1:
        flash("Cannot remove admin status from the last admin user", "danger")
        return redirect(url_for('admin.manage_users'))
    
    # Don't allow changing your own admin status
    if user.id == current_user.id:
        flash("You cannot change your own admin status", "danger")
        return redirect(url_for('admin.manage_users'))
    
    user.is_admin = not user.is_admin
    db.session.commit()
    
    status = "granted" if user.is_admin else "revoked"
    flash(f"Admin privileges {status} for {user.username}", "success")
    return redirect(url_for('admin.manage_users'))

@admin_bp.route('/users/<int:user_id>/delete', methods=['POST'])
@login_required
@admin_required
def delete_user(user_id):
    user = User.query.get_or_404(user_id)
    
    # Don't allow deleting yourself
    if user.id == current_user.id:
        flash("You cannot delete your own account", "danger")
        return redirect(url_for('admin.manage_users'))
    
    # Don't allow deleting the last admin
    if user.is_admin and User.query.filter_by(is_admin=True).count() <= 1:
        flash("Cannot delete the last admin user", "danger")
        return redirect(url_for('admin.manage_users'))
    
    username = user.username
    db.session.delete(user)
    db.session.commit()
    
    flash(f"User '{username}' has been deleted", "success")
    return redirect(url_for('admin.manage_users'))