From 72177e8ab567a1739cbf87e3b5a32d01978a19cb Mon Sep 17 00:00:00 2001
From: Lance Edgar <lance@edbob.org>
Date: Wed, 2 Sep 2020 11:30:02 -0500
Subject: [PATCH] Improve auto-handling of "local" timestamps

for non-Rattail DBs where timestamps are local instead of UTC
---
 tailbone/forms/core.py   |  9 +++++++--
 tailbone/grids/core.py   | 11 ++++++++---
 tailbone/views/master.py | 12 ++++++++++++
 3 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/tailbone/forms/core.py b/tailbone/forms/core.py
index cf7dd49e..7441e4ab 100644
--- a/tailbone/forms/core.py
+++ b/tailbone/forms/core.py
@@ -340,7 +340,8 @@ class Form(object):
     auto_disable_cancel = True
 
     def __init__(self, fields=None, schema=None, request=None, mobile=False, readonly=False, readonly_fields=[],
-                 model_instance=None, model_class=None, appstruct=UNSPECIFIED, nodes={}, enums={}, labels={}, renderers=None,
+                 model_instance=None, model_class=None, appstruct=UNSPECIFIED, nodes={}, enums={}, labels={},
+                 assume_local_times=False, renderers=None,
                  hidden={}, widgets={}, defaults={}, validators={}, required={}, helptext={}, focus_spec=None,
                  action_url=None, cancel_url=None, use_buefy=None, component='tailbone-form'):
 
@@ -364,6 +365,7 @@ class Form(object):
         self.nodes = nodes or {}
         self.enums = enums or {}
         self.labels = labels or {}
+        self.assume_local_times = assume_local_times
         if renderers is None and self.model_class:
             self.renderers = self.make_renderers()
         else:
@@ -430,7 +432,10 @@ class Form(object):
                 if len(prop.columns) == 1:
                     column = prop.columns[0]
                     if isinstance(column.type, sa.DateTime):
-                        renderers[prop.key] = self.render_datetime
+                        if self.assume_local_times:
+                            renderers[prop.key] = self.render_datetime_local
+                        else:
+                            renderers[prop.key] = self.render_datetime
                     elif isinstance(column.type, sa.Boolean):
                         renderers[prop.key] = self.render_boolean
 
diff --git a/tailbone/grids/core.py b/tailbone/grids/core.py
index d475370c..442568de 100644
--- a/tailbone/grids/core.py
+++ b/tailbone/grids/core.py
@@ -2,7 +2,7 @@
 ################################################################################
 #
 #  Rattail -- Retail Software Framework
-#  Copyright © 2010-2019 Lance Edgar
+#  Copyright © 2010-2020 Lance Edgar
 #
 #  This file is part of Rattail.
 #
@@ -69,7 +69,8 @@ class Grid(object):
 
     def __init__(self, key, data, columns=None, width='auto', request=None, mobile=False,
                  model_class=None, model_title=None, model_title_plural=None,
-                 enums={}, labels={}, renderers={}, extra_row_class=None, linked_columns=[], url='#',
+                 enums={}, labels={}, assume_local_times=False, renderers={},
+                 extra_row_class=None, linked_columns=[], url='#',
                  joiners={}, filterable=False, filters={}, use_byte_string_filters=False,
                  sortable=False, sorters={}, default_sortkey=None, default_sortdir='asc',
                  pageable=False, default_pagesize=20, default_page=1,
@@ -102,6 +103,7 @@ class Grid(object):
         self.enums = enums or {}
 
         self.labels = labels or {}
+        self.assume_local_times = assume_local_times
         self.renderers = self.make_default_renderers(renderers or {})
         self.extra_row_class = extra_row_class
         self.linked_columns = linked_columns or []
@@ -407,7 +409,10 @@ class Grid(object):
             return self.render_boolean
 
         if isinstance(coltype, sa.DateTime):
-            return self.render_datetime
+            if self.assume_local_times:
+                return self.render_datetime_local
+            else:
+                return self.render_datetime
 
         if isinstance(coltype, GPCType):
             return self.render_gpc
diff --git a/tailbone/views/master.py b/tailbone/views/master.py
index c2720d6e..6b6c8305 100644
--- a/tailbone/views/master.py
+++ b/tailbone/views/master.py
@@ -424,6 +424,7 @@ class MasterView(View):
             'url': lambda obj: self.get_action_url('view', obj),
             'checkboxes': checkboxes,
             'checked': self.checked,
+            'assume_local_times': self.has_local_times,
         }
         if 'main_actions' not in kwargs and 'more_actions' not in kwargs:
             main, more = self.get_grid_actions()
@@ -2961,6 +2962,16 @@ class MasterView(View):
         Coerce the given data dict record, to a "row" dict suitable for use
         when writing directly to XLSX file.
         """
+        data = dict(data)
+        for key in data:
+            value = data[key]
+
+            # make timestamps local, "zone-naive"
+            if isinstance(value, datetime.datetime):
+                value = localtime(self.rattail_config, value, tzinfo=False)
+
+            data[key] = value
+
         return data
 
     def results_csv(self):
@@ -3504,6 +3515,7 @@ class MasterView(View):
             'model_class': getattr(self, 'model_class', None),
             'action_url': self.request.current_route_url(_query=None),
             'use_buefy': self.get_use_buefy(),
+            'assume_local_times': self.has_local_times,
         }
         if self.creating:
             kwargs.setdefault('cancel_url', self.get_index_url())