Basic reporting example

.gitignore

@@ -1,4 +1,5 @@
 __pycache__
+/drcr/config.py
 /mydata
 /scripts
 /venv

drcr/models.py

@@ -57,3 +57,32 @@ class Amount:
 	
 	def quantity_string(self):
 		return '{:.{dps}f}'.format(self.quantity / (10**AMOUNT_DPS), dps=AMOUNT_DPS)
+
+class TrialBalancer:
+	"""
+	Applies transactions to generate a trial balance
+	"""
+	
+	def __init__(self):
+		self.accounts = {}
+	
+	def apply_transactions(self, transactions):
+		for transaction in transactions:
+			for posting in transaction.postings:
+				if posting.account not in self.accounts:
+					self.accounts[posting.account] = Amount(0, '$')  # FIXME: Other commodities
+				
+				# FIXME: Handle commodities
+				self.accounts[posting.account].quantity += posting.quantity
+	
+	def transfer_balance(self, source_account, destination_account, description=None):
+		"""Transfer the balance of the source account to the destination account"""
+		
+		# TODO: Keep a record of internal transactions?
+		
+		if destination_account not in self.accounts:
+			self.accounts[destination_account] = Amount(0, '$')  # FIXME: Other commodities
+		
+		# FIXME: Handle commodities
+		self.accounts[destination_account].quantity += self.accounts[source_account].quantity
+		del self.accounts[source_account]

drcr/reports/views.py

@@ -0,0 +1,39 @@
+#   DrCr: Web-based double-entry bookkeeping framework
+#   Copyright (C) 2022  Lee Yingtong Li (RunasSudo)
+#
+#   This program is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU Affero General Public License as published by
+#   the Free Software Foundation, either version 3 of the License, or
+#   (at your option) any later version.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU Affero General Public License for more details.
+#
+#   You should have received a copy of the GNU Affero General Public License
+#   along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+from flask import render_template
+
+from ..config import COA_MAPPING
+from ..models import Amount, TrialBalancer
+from ..webapp import all_transactions, app
+
+@app.route('/reports/balance-sheet')
+def balance_sheet():
+	# Extract trial balance
+	balancer = TrialBalancer()
+	balancer.apply_transactions(all_transactions())
+	
+	# Classify accounts
+	for source_account, destination_account in COA_MAPPING.items():
+		balancer.transfer_balance(source_account, destination_account)
+	
+	balancer.transfer_balance('Income', 'Equity')
+	balancer.transfer_balance('Expenses', 'Equity')
+	
+	total_dr = Amount(sum(v.quantity for v in balancer.accounts.values() if v.quantity > 0), '$')
+	total_cr = Amount(sum(v.quantity for v in balancer.accounts.values() if v.quantity < 0), '$')
+	
+	return render_template('trial_balance.html', accounts=dict(sorted(balancer.accounts.items())), total_dr=total_dr, total_cr=total_cr)

drcr/statements/views.py

@@ -23,7 +23,12 @@ from .models import StatementLine, StatementLinePosting, StatementLineTransactio
 
 @app.route('/statement-lines')
 def statement_lines():
-	return render_template('statement_lines.html', statement_lines=StatementLine.query.all())
+	if 'account' in request.args:
+		statement_lines = StatementLine.query.filter_by(source_account=request.args['account']).all()
+	else:
+		statement_lines = StatementLine.query.all()
+	
+	return render_template('statement_lines.html', statement_lines=sorted(statement_lines, key=lambda l: l.dt))
 
 @app.route('/statement-lines/charge', methods=['POST'])
 def statement_line_charge():

drcr/webapp.py

@@ -18,7 +18,7 @@ from flask import Flask, render_template
 
 from .database import db_session, init_db
 from .general_journal.models import GeneralJournalTransaction
-from .models import Amount
+from .models import Amount, TrialBalancer
 from .statements.models import StatementLine, StatementLineTransaction
 
 app = Flask(__name__)
@@ -40,22 +40,16 @@ def general_ledger():
 
 @app.route('/trial-balance')
 def trial_balance():
-	# Get balances
-	accounts = {}
+	balancer = TrialBalancer()
+	balancer.apply_transactions(all_transactions())
 	
-	for transaction in all_transactions():
-		for posting in transaction.postings:
-			if posting.account not in accounts:
-				accounts[posting.account] = Amount(0, '$')
-			
-			accounts[posting.account].quantity += posting.quantity
+	total_dr = Amount(sum(v.quantity for v in balancer.accounts.values() if v.quantity > 0), '$')
+	total_cr = Amount(sum(v.quantity for v in balancer.accounts.values() if v.quantity < 0), '$')
 	
-	total_dr = Amount(sum(v.quantity for v in accounts.values() if v.quantity > 0), '$')
-	total_cr = Amount(sum(v.quantity for v in accounts.values() if v.quantity < 0), '$')
-	
-	return render_template('trial_balance.html', accounts=dict(sorted(accounts.items())), total_dr=total_dr, total_cr=total_cr)
+	return render_template('trial_balance.html', accounts=dict(sorted(balancer.accounts.items())), total_dr=total_dr, total_cr=total_cr)
 
 from .general_journal import views
+from .reports import views
 from .statements import views
 
 @app.cli.command('initdb')