[IMP] sale_timesheet: compute partner_id in project when SOL is set

Before this commit, the user can choose any SOL for any customer in the
sale_line_id field of the project and also in the employee mappings.
The problem is when the user create a task for a customer A, the default
SOL of the project can be no selected if this SOL is not for the
customer A. Also, some employee mappings can be unused for this task if
the SOL of the employee mapping is not for the customer A.
Moreover, if the customer selects a customer in the project, the SOL
initially choose in this project can be removed if the customer is not
the same.

For these reasons, the commit adds a compute for the partner_id field in
the project.project model. This compute is trigger when the user select
a default sales order item (SOL) for the project or select an SOL in the
first employee mappings for this project. With this changes, the SOLs
choose will be for only one partner (customer) in a project.

task-2442683

closes #66181

addons/sale_timesheet/models/project.py

@@ -49,6 +49,7 @@ class Project(models.Model):
         compute="_compute_timesheet_product_id", store=True, readonly=False,
         default=_default_timesheet_product_id)
     warning_employee_rate = fields.Boolean(compute='_compute_warning_employee_rate')
+    partner_id = fields.Many2one(compute='_compute_partner_id', store=True, readonly=False)
 
     @api.depends('sale_line_id', 'sale_line_employee_ids', 'allow_billable')
     def _compute_pricing_type(self):
@@ -137,6 +138,15 @@ class Project(models.Model):
         for project in self.filtered(lambda p: not p.project_overview):
             project.project_overview = project.allow_billable or project.allow_timesheets
 
+    @api.depends('sale_line_employee_ids.sale_line_id', 'sale_line_id')
+    def _compute_partner_id(self):
+        for project in self:
+            if project.partner_id:
+                continue
+            if project.allow_billable and project.allow_timesheets and project.pricing_type != 'task_rate':
+                sol = project.sale_line_id or project.sale_line_employee_ids.sale_line_id[:1]
+                project.partner_id = sol.order_partner_id
+
     @api.constrains('sale_line_id')
     def _check_sale_line_type(self):
         for project in self.filtered(lambda project: project.sale_line_id):

addons/sale_timesheet/models/project_sale_line_employee_map.py

@@ -26,9 +26,14 @@ class ProjectProductEmployeeMap(models.Model):
         ('uniqueness_employee', 'UNIQUE(project_id,employee_id)', 'An employee cannot be selected more than once in the mapping. Please remove duplicate(s) and try again.'),
     ]
 
-    @api.depends('project_id.partner_id')
+    @api.depends('partner_id')
     def _compute_sale_line_id(self):
-        self.filtered(lambda map_entry: map_entry.sale_line_id.order_partner_id != map_entry.project_id.partner_id).update({'sale_line_id': False})
+        self.filtered(
+            lambda map_entry:
+                map_entry.sale_line_id
+                and map_entry.partner_id
+                and map_entry.sale_line_id.order_partner_id.commercial_partner_id != map_entry.partner_id.commercial_partner_id
+        ).update({'sale_line_id': False})
 
     @api.depends('sale_line_id', 'sale_line_id.price_unit')
     def _compute_price_unit(self):

addons/sale_timesheet/views/project_task_views.xml

@@ -31,7 +31,6 @@
                     <field name="sale_line_employee_ids">
                         <tree editable="bottom">
                             <field name="company_id" invisible="1"/>
-                            <field name="project_id" invisible="1"/>
                             <field name="partner_id" invisible="1"/>
                             <field name="employee_id" options="{'no_create': True}"/>
                             <field name="sale_line_id" attrs="{'required': True}" options="{'no_create': True}"/>