#   DrCr: Web-based double-entry bookkeeping framework
#   Copyright (C) 2022–2024  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 .database import db
from .models import Transaction
from .plugins import transaction_providers
from .statements.models import StatementLine

def limit_query_dt(query, field, start_date=None, end_date=None):
	"""Helper function to limit the query between the start and end dates"""
	
	if start_date and end_date:
		return query.where((field >= start_date) & (field <= end_date))
	if start_date:
		return query.where(field >= start_date)
	if end_date:
		return query.where(field <= end_date)
	return query

def all_transactions(start_date=None, end_date=None, api_stage_until=None, join_postings=True):
	"""Return all transactions, including from DB and API"""
	
	transactions = db_transactions(start_date=start_date, end_date=end_date, join_postings=join_postings)
	transactions.extend(api_transactions(start_date=start_date, end_date=end_date, api_stage_until=api_stage_until))
	return transactions

def db_transactions(start_date=None, end_date=None, join_postings=True):
	"""Return only transactions from DB"""
	
	# All Transactions in database between start_date and end_date
	query = db.select(Transaction)
	query = limit_query_dt(query, Transaction.dt, start_date, end_date)
	if join_postings:
		query = query.options(db.selectinload(Transaction.postings))
	
	transactions = db.session.scalars(query).all()
	return transactions

def api_transactions(start_date=None, end_date=None, api_stage_until=None):
	"""Return only transactions from API"""
	
	# Stage 0:   DB transactions
	# Stage 100: Ordinary transactions
	# Stage 200: Closing entries prior to tax
	# Stage 300: Tax entries
	# Stage 400: Closing entries after tax
	
	transactions = []
	
	# Unreconciled StatementLines
	query = db.select(StatementLine).where(StatementLine.reconciliation == None)
	query = limit_query_dt(query, StatementLine.dt, start_date, end_date)
	transactions.extend(line.into_transaction() for line in db.session.scalars(query).all())
	
	# Plugins
	for transaction_provider in transaction_providers:
		transactions = transaction_provider(transactions, start_date=start_date, end_date=end_date, api_stage_until=api_stage_until)
	
	return transactions