from odoo import fields, models


class SaleOrder(models.Model):
    _inherit = 'sale.order'

    order_promotion_ids = fields.One2many('sale.order.promotion', 'order_id', 'Promotions')

    def add_free_product(self, promotions):
        for promotion in promotions:
            program_line = self.env['promotion.program.line'].browse(promotion['program_line_id'])
            for free_product in program_line.free_product_ids:
                if free_product.product_id.merchandise_ok:
                    self.env['sale.order.line'].create({
                        'order_id': self.id,
                        'name': f"Free Product {free_product.product_id.display_name} Quantity ({free_product.qty})",
                        'display_type': 'line_note'
                    })

    def apply_promotion_program(self):
        userdata = {
            'user_id': self.partner_id.user_id.id,
            'partner_id': self.partner_id.id
        }
        
        order_lines = []
        iu_products = [] # Internal Use products
        for line in self.order_promotion_ids:
            promotion = line.program_line_id.format(user=userdata, qty=line.quantity)

            products = promotion['products']
            free_products = promotion['free_products']
            all_products = products.copy()

            if promotion['promotion_type']['value'] == 'merchandise':
                iu_products += filter(lambda x: x['qty'] > 0, free_products)
            else:
                all_products = self._merge_promotion_products(promotion)

            promotion_price = promotion['price']['price_discount'] * line.quantity * 1.11
            promotion_amt_total = sum(product['price']['price'] * product['qty'] for product in all_products)

            promotion_used_price = 0
            for index, product in enumerate(all_products):
                order_line_default = {
                    'company_id': 1,
                    'order_id': self.id,
                    'order_promotion_id': line.id,
                    'product_id': product['id'],
                    'product_uom_qty': product['qty'],
                }
                if promotion['promotion_type']['value'] == 'special_price':
                    order_lines.append({
                        **order_line_default,
                        'price_unit': product['price']['price'],
                        'discount': product['price']['discount_percentage']
                    })
                    continue

                product_price = product['price']['price']
                contrib_decimal = product_price * product['qty'] / promotion_amt_total

                if index < len(all_products) - 1:
                    contrib_price = contrib_decimal * promotion_price
                else:
                    contrib_price = promotion_price - promotion_used_price
                
                contrib_price_unit = contrib_price / product['qty']
                contrib_disc_unit = round((product_price - contrib_price_unit) / product_price * 100, 2)
                
                product_subtotal = round((100 - contrib_disc_unit) / 100 * product_price, 2) * product['qty']
                promotion_used_price += product_subtotal

                order_lines.append({
                    **order_line_default,
                    'price_unit': product_price,
                    'discount': contrib_disc_unit
                })

        self.env['sale.order.line'].create(order_lines)
        self._create_promotion_program_iu_docs(iu_products)

    def _merge_promotion_products(self, promotion):
        """
            Merges the products and free products from a promotion into a single dictionary.

            Parameters:
                promotion (dict): A dictionary representing a promotion with 'products' and 'free_products' keys.

            Returns:
                list: A list containing the merged products from the promotion.
        """
        merged_products = {}

        for product in promotion['products'] + promotion['free_products']:
            product_id = product['id']
            product_qty = product['qty']
            if product_id in merged_products:
                merged_products[product_id]['qty'] += product_qty
            else:
                merged_products[product_id] = product
        
        return list(merged_products.values())

    def _create_promotion_program_iu_docs(self, products):
        if len(products) == 0:
            return False
        
        default = {
            'picking_type_id': 33, # PT Indoteknik (Bandengan): Internal Transfers
            'location_id': 57, # BU/Stock
            'location_dest_id': 49, # Virtual Locations/Internal Use
            'account_id': 596, # Biaya awareness
            'product_uom': 1 # Unit
        }
        
        picking_type = self.env['stock.picking.type'].browse(default['picking_type_id'])
        picking = self.env['stock.picking'].create({
            'name': picking_type.sequence_id.next_by_id(),
            'picking_type_id': default['picking_type_id'],
            'partner_id': self.partner_id.id,
            'real_shipping_id': self.real_shipping_id.id,
            'location_id': default['location_id'],
            'location_dest_id': default['location_dest_id'],
            'account_id': default['account_id'],
            'origin': self.display_name,
            'is_internal_use': True
        })

        for product in products:
            picking.move_ids_without_package.create({
                'product_id': product['id'],
                'name': product['display_name'],
                'product_uom_qty': product['qty'],
                'product_uom': default['product_uom'],
                'location_id': default['location_id'],
                'location_dest_id': default['location_dest_id'],
                'picking_id': picking.id
            })

        self.picking_iu_id = picking.id