From d5d9c644a26022966c7d8eec3b6635df1b21b40e Mon Sep 17 00:00:00 2001
From: Lance Edgar <lance@edbob.org>
Date: Thu, 8 Dec 2022 18:19:32 -0600
Subject: [PATCH] Add the ViewSupplement concept

also fix cell-class for grid columns.  cannot use "raw" fieldname
because in some cases (e.g. 'number', 'rate') Bulma may interpret that
as actually meaning something, and affect the display
---
 tailbone/app.py                        |  12 +++
 tailbone/templates/grids/buefy.mako    |   2 +-
 tailbone/templates/receiving/view.mako |   8 +-
 tailbone/views/__init__.py             |   4 +-
 tailbone/views/customers.py            |   5 +-
 tailbone/views/departments.py          |  12 ++-
 tailbone/views/master.py               | 118 ++++++++++++++++++++++++-
 tailbone/views/subdepartments.py       |   4 +-
 tailbone/views/vendors/core.py         |   2 +-
 9 files changed, 153 insertions(+), 14 deletions(-)

diff --git a/tailbone/app.py b/tailbone/app.py
index d7155829..1cfae6b2 100644
--- a/tailbone/app.py
+++ b/tailbone/app.py
@@ -177,6 +177,7 @@ def make_pyramid_config(settings, configure_csrf=True):
     # and some similar magic for certain master views
     config.add_directive('add_tailbone_index_page', 'tailbone.app.add_index_page')
     config.add_directive('add_tailbone_config_page', 'tailbone.app.add_config_page')
+    config.add_directive('add_tailbone_view_supplement', 'tailbone.app.add_view_supplement')
 
     config.add_directive('add_tailbone_websocket', 'tailbone.app.add_websocket')
 
@@ -239,6 +240,17 @@ def add_config_page(config, route_name, label, permission):
     config.action(None, action)
 
 
+def add_view_supplement(config, route_prefix, cls):
+    """
+    Register a master view supplement for the app.
+    """
+    def action():
+        supplements = config.get_settings().get('tailbone_view_supplements', {})
+        supplements.setdefault(route_prefix, []).append(cls)
+        config.add_settings({'tailbone_view_supplements': supplements})
+    config.action(None, action)
+
+
 def establish_theme(settings):
     rattail_config = settings['rattail_config']
 
diff --git a/tailbone/templates/grids/buefy.mako b/tailbone/templates/grids/buefy.mako
index 9d8359d9..47e9a2dc 100644
--- a/tailbone/templates/grids/buefy.mako
+++ b/tailbone/templates/grids/buefy.mako
@@ -221,7 +221,7 @@
                             % if grid.is_searchable(column['field']):
                             searchable
                             % endif
-                            cell-class="${column['field']}"
+                            cell-class="c_${column['field']}"
                             % if grid.has_click_handler(column['field']):
                             @click.native="${grid.click_handlers[column['field']]}"
                             % endif
diff --git a/tailbone/templates/receiving/view.mako b/tailbone/templates/receiving/view.mako
index b16aa5b8..f4a90dcb 100644
--- a/tailbone/templates/receiving/view.mako
+++ b/tailbone/templates/receiving/view.mako
@@ -267,20 +267,20 @@
   % if use_buefy:
       <style type="text/css">
         % if allow_edit_catalog_unit_cost:
-            td.catalog_unit_cost {
+            td.c_catalog_unit_cost {
                 cursor: pointer;
                 background-color: #fcc;
             }
-            tr.catalog_cost_confirmed td.catalog_unit_cost {
+            tr.catalog_cost_confirmed td.c_catalog_unit_cost {
                 background-color: #cfc;
             }
         % endif
         % if allow_edit_invoice_unit_cost:
-            td.invoice_unit_cost {
+            td.c_invoice_unit_cost {
                 cursor: pointer;
                 background-color: #fcc;
             }
-            tr.invoice_cost_confirmed td.invoice_unit_cost {
+            tr.invoice_cost_confirmed td.c_invoice_unit_cost {
                 background-color: #cfc;
             }
         % endif
diff --git a/tailbone/views/__init__.py b/tailbone/views/__init__.py
index 6b6ebc19..29c73b61 100644
--- a/tailbone/views/__init__.py
+++ b/tailbone/views/__init__.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  Rattail -- Retail Software Framework
-#  Copyright © 2010-2021 Lance Edgar
+#  Copyright © 2010-2022 Lance Edgar
 #
 #  This file is part of Rattail.
 #
@@ -27,7 +27,7 @@ Pyramid Views
 from __future__ import unicode_literals, absolute_import
 
 from .core import View
-from .master import MasterView
+from .master import MasterView, ViewSupplement
 
 
 def includeme(config):
diff --git a/tailbone/views/customers.py b/tailbone/views/customers.py
index a905ea07..0ce0ad44 100644
--- a/tailbone/views/customers.py
+++ b/tailbone/views/customers.py
@@ -115,6 +115,10 @@ class CustomerView(MasterView):
 
     def configure_grid(self, g):
         super(CustomerView, self).configure_grid(g)
+        model = self.model
+
+        # number
+        g.set_link('number')
 
         # name
         g.filters['name'].default_active = True
@@ -158,7 +162,6 @@ class CustomerView(MasterView):
             g.filters['active_in_pos'].default_verb = 'is_true'
 
         g.set_link('id')
-        g.set_link('number')
         g.set_link('name')
         g.set_link('person')
         g.set_link('email')
diff --git a/tailbone/views/departments.py b/tailbone/views/departments.py
index 96dcfb61..a0212d63 100644
--- a/tailbone/views/departments.py
+++ b/tailbone/views/departments.py
@@ -66,6 +66,7 @@ class DepartmentView(MasterView):
 
     has_rows = True
     model_row_class = model.Product
+    rows_title = "Products"
 
     row_labels = {
         'upc': "UPC",
@@ -83,13 +84,18 @@ class DepartmentView(MasterView):
 
     def configure_grid(self, g):
         super(DepartmentView, self).configure_grid(g)
+
+        # number
+        g.set_sort_defaults('number')
+        g.set_link('number')
+
+        # name
         g.filters['name'].default_active = True
         g.filters['name'].default_verb = 'contains'
-        g.set_sort_defaults('number')
+        g.set_link('name')
+
         g.set_type('product', 'boolean')
         g.set_type('personnel', 'boolean')
-        g.set_link('number')
-        g.set_link('name')
 
     def configure_form(self, f):
         super(DepartmentView, self).configure_form(f)
diff --git a/tailbone/views/master.py b/tailbone/views/master.py
index af776d97..7e1925a2 100644
--- a/tailbone/views/master.py
+++ b/tailbone/views/master.py
@@ -259,6 +259,8 @@ class MasterView(View):
         Collect all labels defined within the master class hierarchy.
         """
         labels = {}
+        for supp in self.iter_view_supplements():
+            labels.update(supp.labels)
         hierarchy = self.get_class_hierarchy()
         for cls in hierarchy:
             if hasattr(cls, 'labels'):
@@ -473,6 +475,9 @@ class MasterView(View):
 
         self.configure_column_product_key(grid)
 
+        for supp in self.iter_view_supplements():
+            supp.configure_grid(grid)
+
     def grid_extra_class(self, obj, i):
         """
         Returns string of extra class(es) for the table row corresponding to
@@ -1226,7 +1231,10 @@ class MasterView(View):
         If applicable, should return a list of child classes which should be
         considered when querying for version history of an object.
         """
-        return []
+        classes = []
+        for supp in self.iter_view_supplements():
+            classes.extend(supp.get_version_child_classes())
+        return classes
 
     def normalize_version_child_classes(self):
         classes = []
@@ -2707,6 +2715,9 @@ class MasterView(View):
             if not self.has_perm('view_global'):
                 query = query.filter(model_class.local_only == True)
 
+        for supp in self.iter_view_supplements():
+            query = supp.get_grid_query(query)
+
         return query
 
     def get_effective_query(self, session=None, **kwargs):
@@ -3826,6 +3837,17 @@ class MasterView(View):
         defaults.update(kwargs)
         return defaults
 
+    def iter_view_supplements(self):
+        """
+        Iterate over all registered supplements for this master view.
+        """
+        supplements = self.request.registry.settings['tailbone_view_supplements']
+        route_prefix = self.get_route_prefix()
+        if supplements and route_prefix in supplements:
+            for cls in supplements[route_prefix]:
+                supp = cls(self)
+                yield supp
+
     def configure_form(self, form):
         """
         Configure the main "desktop" form for the view's data model.
@@ -3834,6 +3856,9 @@ class MasterView(View):
 
         self.configure_field_product_key(form)
 
+        for supp in self.iter_view_supplements():
+            supp.configure_form(form)
+
     def validate_form(self, form):
         if form.validate(newstyle=True):
             self.form_deserialized = form.validated
@@ -5009,3 +5034,94 @@ class MasterView(View):
                                  '{}/rows/{{row_uuid}}/delete'.format(instance_url_prefix))
                 config.add_view(cls, attr='delete_row', route_name='{}.delete_row'.format(route_prefix),
                                 permission='{}.delete_row'.format(permission_prefix))
+
+
+class ViewSupplement(object):
+    """
+    Base class for view "supplements" - which are sort of like plugins
+    which can "supplement" certain aspects of the view.
+
+    Instead of subclassing a master view and "supplementing" it via
+    method overrides etc., packages can instead define one or more
+    ``ViewSupplement`` classes.  All such supplements are registered
+    so they can be located; their logic is then merged into the
+    appropriate master view at runtime.
+
+    The primary use case for this is within integration packages, such
+    as tailbone-corepos and the like.  A truly custom app might want
+    supplemental logic from multiple integration packages, in which
+    case the "subclassing" approach sort of falls apart.
+
+    :attribute:: labels
+
+       This can be a dict of extra field labels to be used by the
+       master view.  Same meaning as for
+       :attr:`tailbone.views.master.MasterView.labels`.
+    """
+    labels = {}
+
+    def __init__(self, master):
+        self.master = master
+
+    @property
+    def model(self):
+        return self.master.model
+
+    def get_grid_query(self, query):
+        """
+        Return the "base" query for the grid.  This is invoked from
+        within :meth:`tailbone.views.master.MasterView.query()`.
+
+        A typical grid query is
+        essentially:
+
+        .. code-block:: sql
+
+           SELECT * FROM mytable
+
+        But when a schema extension is in "primary" use, meaning for
+        instance one of the main grid columns displays extension data,
+        it may be helpful for the base query to join the extension
+        table, as opposed to doing a "just in time" join based on
+        sorting and/or filters:
+
+        .. code-block:: sql
+
+           SELECT * FROM mytable m
+           LEFT OUTER JOIN myextension e ON e.uuid = m.uuid
+
+        This is accomplished by subjecting the current base query to a
+        join, e.g. something like::
+
+           model = self.model
+           query = query.outerjoin(model.MyExtension)
+           return query
+        """
+        return query
+
+    def configure_grid(self, g):
+        """
+        Configure the grid as needed, e.g. add columns, and set
+        renderers etc. for them.
+        """
+
+    def configure_form(self, f):
+        """
+        Configure the form as needed, e.g. add fields, and set
+        renderers, default values etc. for them.
+        """
+
+    def get_version_child_classes(self):
+        """
+        Return a list of additional "version child classes" which are
+        to be taken into account when displaying version history for a
+        given record.
+
+        See also
+        :meth:`tailbone.views.master.MasterView.get_version_child_classes()`.
+        """
+        return []
+
+    @classmethod
+    def defaults(cls, config):
+        config.add_tailbone_view_supplement(cls.route_prefix, cls)
diff --git a/tailbone/views/subdepartments.py b/tailbone/views/subdepartments.py
index d2a337cc..84a34dee 100644
--- a/tailbone/views/subdepartments.py
+++ b/tailbone/views/subdepartments.py
@@ -85,6 +85,9 @@ class SubdepartmentView(MasterView):
     def configure_grid(self, g):
         super(SubdepartmentView, self).configure_grid(g)
 
+        # number
+        g.set_link('number')
+
         # name
         g.filters['name'].default_active = True
         g.filters['name'].default_verb = 'contains'
@@ -95,7 +98,6 @@ class SubdepartmentView(MasterView):
         g.set_sorter('department', model.Department.name)
         g.set_filter('department', model.Department.name)
 
-        g.set_link('number')
         g.set_link('name')
 
     def configure_form(self, f):
diff --git a/tailbone/views/vendors/core.py b/tailbone/views/vendors/core.py
index 87b2de75..a55c351b 100644
--- a/tailbone/views/vendors/core.py
+++ b/tailbone/views/vendors/core.py
@@ -165,7 +165,7 @@ class VendorView(MasterView):
             self.Session.delete(cost)
 
     def get_version_child_classes(self):
-        return [
+        return super(VendorView, self).get_version_child_classes() + [
             (model.VendorPhoneNumber, 'parent_uuid'),
             (model.VendorEmailAddress, 'parent_uuid'),
             (model.VendorContact, 'vendor_uuid'),