fix(dashboard): simpler way to get account timeline from first principles

erpnext/accounts/dashboard_chart_source/account_balance_timeline/account_balance_timeline.py

@@ -9,6 +9,8 @@ from frappe.core.page.dashboard.dashboard import cache_source
 from frappe.utils import add_to_date, date_diff, getdate, nowdate
 from erpnext.accounts.report.general_ledger.general_ledger import execute
 
+from frappe.utils.nestedset import get_descendants_of
+
 @frappe.whitelist()
 @cache_source
 def get(filters=None):
@@ -19,35 +21,56 @@ def get(filters=None):
 
 	from_date = get_from_date_from_timespan(timespan)
 	to_date = nowdate()
-	filters = frappe._dict({
-		"company": company,
-		"from_date": from_date,
-		"to_date": to_date,
-		"account": account,
-		"group_by": "Group by Voucher (Consolidated)"
-	})
-	report_results = execute(filters=filters)[1]
 
-	interesting_fields = ["posting_date", "balance"]
+	# fetch dates to plot
+	dates = get_dates_from_timegrain(from_date, to_date, timegrain)
 
-	_results = []
-	for row in report_results[1:-2]:
-		_results.append([row[key] for key in interesting_fields])
+	# get all the entries for this account and its descendants
+	gl_entries = get_gl_entries(account, to_date)
 
-	_results = add_opening_balance(from_date, _results, report_results[0])
-	grouped_results = groupby(_results, key=itemgetter(0))
-	results = [list(values)[-1] for key, values in grouped_results]
-	results = add_missing_dates(results, from_date, to_date)
-	results = granulate_results(results, from_date, to_date, timegrain)
+	# compile balance values
+	result = build_result(account, dates, gl_entries)
 
 	return {
-		"labels": [result[0] for result in results],
+		"labels": [r[0].strftime('%Y-%m-%d') for r in result],
 		"datasets": [{
 			"name": account,
-			"values": [result[1] for result in results]
+			"values": [r[1] for r in result]
 		}]
 	}
 
+def build_result(account, dates, gl_entries):
+	result = [[getdate(date), 0.0] for date in dates]
+
+	# start with the first date
+	date_index = 0
+
+	# get balances in debit
+	for entry in gl_entries:
+
+		# find the date index after the posting date
+		while getdate(entry.posting_date) > result[date_index][0]:
+			date_index += 1
+
+		result[date_index][1] += entry.debit - entry.credit
+
+	# if account type is credit, switch balances
+	if frappe.db.get_value('Account', account, 'root_type') not in ('Asset', 'Expense'):
+		for r in result:
+			r[1] = -1 * r[1]
+
+	return result
+
+def get_gl_entries(account, to_date):
+	child_accounts = get_descendants_of('Account', account, ignore_permissions=True)
+
+	return frappe.db.get_all('GL Entry',
+		fields = ['posting_date', 'debit', 'credit'],
+		filters = [
+			dict(posting_date = ('<', to_date)),
+			dict(account = ('in', child_accounts))
+		])
+
 def get_from_date_from_timespan(timespan):
 	days = months = years = 0
 	if "Last Week" == timespan:
@@ -61,24 +84,6 @@ def get_from_date_from_timespan(timespan):
 	return add_to_date(None, years=years, months=months, days=days,
 		as_string=True, as_datetime=True)
 
-
-def add_opening_balance(from_date, _results, opening):
-	if not _results or (_results[0][0] != getdate(from_date)):
-		_results.insert(0, [from_date, opening.balance])
-	return _results
-
-def add_missing_dates(incomplete_results, from_date, to_date):
-	day_count = date_diff(to_date, from_date)
-
-	results_dict = dict(incomplete_results)
-	last_balance = incomplete_results[0][1]
-	results = []
-	for date in (add_to_date(getdate(from_date), days=n) for n in range(day_count + 1)):
-		if date in results_dict:
-			last_balance = results_dict[date]
-		results.append([date, last_balance])
-	return results
-
 def get_dates_from_timegrain(from_date, to_date, timegrain):
 	days = months = years = 0
 	if "Daily" == timegrain:
@@ -94,7 +99,3 @@ def get_dates_from_timegrain(from_date, to_date, timegrain):
 	while dates[-1] <= to_date:
 		dates.append(add_to_date(dates[-1], years=years, months=months, days=days))
 	return dates
-
-def granulate_results(incomplete_results, from_date, to_date, timegrain):
-	dates = set(get_dates_from_timegrain(getdate(from_date), getdate(to_date), timegrain))
-	return list(filter(lambda x: x[0] in dates,incomplete_results))