import os
import json
import stripe
from typing import List, Tuple

def parse_product_quantities(product_quantities_str: str) -> List[Tuple[str, int]]:
    """Parse a product quantities string into a list of (product_id, quantity) tuples.
    
    Args:
        product_quantities_str: String with format "(product_1,k_1),(product_2,k_2),...,(product_n,k_n)"
            where product_i must match a key in products.json and k_i is the quantity.
            Example: "(finasteride,1),(NP_consultation,1)"
    
    Returns:
        List of tuples containing (product_id, quantity)
    
    Raises:
        ValueError: If the input string format is invalid
    """
    product_quantities = []
    pairs = product_quantities_str.strip().split("),(")
    
    for pair in pairs:
        # Clean up the pair string
        pair = pair.replace("(", "").replace(")", "")
        if not pair:
            continue
            
        parts = pair.split(",")
        if len(parts) != 2:
            raise ValueError(f"Invalid format in pair: {pair}. Expected 'product,quantity'")
            
        product_id, quantity_str = parts
        try:
            quantity = int(quantity_str)
        except ValueError:
            raise ValueError(f"Quantity must be an integer: {quantity_str}")
            
        product_quantities.append((product_id, quantity))
    
    return product_quantities

def generate_payment_link(product_quantities_str: str) -> str:
    """Generate a Stripe payment link for specified products.
    
    Args:
        product_quantities_str: String describing products and quantities
            Format: "(product_1,k_1),(product_2,k_2),...,(product_n,k_n)"
            Example: "(finasteride,1),(NP_consultation,1)"
    
    Returns:
        Stripe payment link URL
    
    Raises:
        ValueError: If products are not found or quantities are invalid
        stripe.error.StripeError: If there's an error with the Stripe API
    """
    try:
        # Parse the product quantities
        product_quantities = parse_product_quantities(product_quantities_str)
        
        # Load the product catalog
        script_dir = os.path.dirname(os.path.abspath(__file__))
        catalog_path = os.path.join(script_dir, "products.json")
        
        try:
            with open(catalog_path, 'r') as f:
                catalog = json.load(f)
        except (FileNotFoundError, json.JSONDecodeError) as e:
            raise ValueError(f"Error loading product catalog: {str(e)}")
        
        # Create line items for the payment link
        price_quantities = {}
        for product_id, quantity in product_quantities:
            if product_id not in catalog:
                raise ValueError(f"Product '{product_id}' not found in catalog")
            
            price_id = catalog[product_id]["price_id"]
            price_quantities[price_id] = price_quantities.get(price_id, 0) + quantity
        
        # Create line items from the consolidated price_quantities
        line_items = [
            {"price": price_id, "quantity": quantity}
            for price_id, quantity in price_quantities.items()
        ]
        
        # Create the payment link
        payment_link = stripe.PaymentLink.create(
            line_items=line_items,
            phone_number_collection={"enabled": True},
            after_completion={
                "type": "hosted_confirmation",
                "hosted_confirmation": {
                    "custom_message": "Thank you for your order! 🎉\nA nurse practitioner will review your order and contact you shortly."
                }
            }
        )
        
        return payment_link.url
        
    except stripe.error.StripeError as e:
        raise ValueError(f"Stripe API error: {str(e)}")

def create_non_recurring_item_with_price(product_name: str, price: int, description: str = "Default description") -> stripe.Product:
    """Create a new Stripe product with a non-recurring price.
    
    Args:
        product_name: Name of the product
        price: Price in cents
        description: Product description
    
    Returns:
        Stripe Product object
    
    Raises:
        stripe.error.StripeError: If there's an error with the Stripe API
    """
    try:
        item = stripe.Product.create(
            name=product_name,
            description=description,
            default_price_data={
                "unit_amount": price,
                "currency": "usd",
            },
            expand=["default_price"]
        )
        
        print(f"Created product with id: {item.id}")
        print(f"Created price with id: {item.default_price.id}")
        
        return item
        
    except stripe.error.StripeError as e:
        raise ValueError(f"Error creating Stripe product: {str(e)}")