from odoo import models, fields, api, _
from odoo.exceptions import UserError
import datetime

class StockPicking(models.Model):
    _inherit = 'stock.picking'

    def action_generate_asset_codes(self):
        self.ensure_one()
        for move in self.move_ids_without_package:
            # Only generate if product creates asset (optional check, but good practice)
            # However, user wants to manually decide, so we generate for all lines that look like assets?
            # Let's assume user triggers this button for asset receipts.
            # We can check if product has an asset model set in accounting? 
            # Or just blindly generate if missing? 
            # Re-using logic from account.asset.create:
            
            if not move.asset_code and move.product_id:
                sequence = self.env['ir.sequence'].next_by_code('ga.asset.code') or '00000'
                year = datetime.datetime.now().year
                
                # Logic from AccountAsset create: [Barcode or AST]/[Year]/[Sequence]
                prefix = move.product_id.barcode or 'AST'
                
                # Note: Sequence next_by_code returns '/0000X' as configured in XML
                move.asset_code = f"{prefix}/{year}{sequence}"

    has_asset_moves = fields.Boolean(compute='_compute_has_asset_moves', store=True)

    @api.depends('move_ids.product_id', 'picking_type_code')
    def _compute_has_asset_moves(self):
        for pick in self:
            has_asset = False
            if pick.picking_type_code == 'incoming':
                for move in pick.move_ids_without_package:
                    # Check if product is configured to create assets
                    # Logic: Check Product's Expense Account or Category's Expense Account
                    account = move.product_id.property_account_expense_id or move.product_id.categ_id.property_account_expense_categ_id
                    if account and account.create_asset != 'no':
                        has_asset = True
                        break
            pick.has_asset_moves = has_asset

    def button_validate(self):
        # Validation Check
        for pick in self:
            if pick.has_asset_moves:
                for move in pick.move_ids_without_package:
                    account = move.product_id.property_account_expense_id or move.product_id.categ_id.property_account_expense_categ_id
                    if account and account.create_asset != 'no' and not move.asset_code:
                        raise UserError(_(
                            "Asset Code is missing for product '%s'. \n"
                            "Please click 'Generate Asset Codes' before validating.", 
                            move.product_id.name
                        ))
        return super(StockPicking, self).button_validate()

    def _action_done(self):
        res = super(StockPicking, self)._action_done()
        
        # After validation, create assets for moves with asset_code
        for pick in self:
            for move in pick.move_ids_without_package:
                if move.asset_code and not move.asset_id:
                    # Get Account to check configuration
                    account = move.product_id.property_account_expense_id or move.product_id.categ_id.property_account_expense_categ_id
                    
                    # Prepare basic values
                    vals_base = {
                        'name': move.product_id.name,
                        'product_id': move.product_id.id,
                        'acquisition_date': fields.Date.today(),
                        'company_id': move.company_id.id,
                        'state': 'draft', 
                    }
                    
                    # Add Model if configured on Account
                    if account and account.asset_model:
                        vals_base['model_id'] = account.asset_model.id
                    
                    qty = int(move.quantity)
                    
                    # CASE 1: Multiple Assets per Line
                    if account and account.multiple_assets_per_line and qty > 1:
                        # 1st Asset uses the pre-generated code
                        vals = vals_base.copy()
                        vals['asset_code'] = move.asset_code
                        vals['original_value'] = move.price_unit # Per unit value
                        
                        asset = self.env['account.asset'].create(vals)
                        move.asset_id = asset.id # Link first one to move
                        
                        # Create remaining assets
                        for i in range(qty - 1):
                            vals_extra = vals_base.copy()
                            vals_extra['original_value'] = move.price_unit
                            
                            # Generate new code for extra assets
                            sequence = self.env['ir.sequence'].next_by_code('ga.asset.code') or '00000'
                            year = datetime.datetime.now().year
                            prefix = move.product_id.barcode or 'AST'
                            vals_extra['asset_code'] = f"{prefix}/{year}{sequence}"
                            
                            self.env['account.asset'].create(vals_extra)
                            
                    # CASE 2: Single Assset (default)
                    else:
                        vals = vals_base.copy()
                        vals['asset_code'] = move.asset_code
                        vals['original_value'] = move.price_unit * move.quantity # Total Value
                        
                        asset = self.env['account.asset'].create(vals)
                        move.asset_id = asset.id
        return res