# Copyright (c) 2013, Frappe Technologies Pvt. Ltd. and contributors
# For license information, please see license.txt

from __future__ import unicode_literals
import frappe
from frappe import _
from frappe.utils import cint
from erpnext.accounts.report.financial_statements import (get_period_list, get_columns, get_data)
from erpnext.accounts.report.profit_and_loss_statement.profit_and_loss_statement import get_net_profit_loss
from erpnext.accounts.utils import get_fiscal_year


def execute(filters=None):
	if cint(frappe.db.get_single_value('Accounts Settings', 'use_custom_cash_flow')):
		from erpnext.accounts.report.cash_flow.custom_cash_flow import execute as execute_custom
		return execute_custom(filters=filters)
		
	period_list = get_period_list(filters.from_fiscal_year, filters.to_fiscal_year, 
		filters.periodicity, filters.accumulated_values, filters.company)

	cash_flow_accounts = get_cash_flow_accounts()

	# compute net profit / loss
	income = get_data(filters.company, "Income", "Credit", period_list, filters=filters,
		accumulated_values=filters.accumulated_values, ignore_closing_entries=True, ignore_accumulated_values_for_fy= True)
	expense = get_data(filters.company, "Expense", "Debit", period_list, filters=filters,
		accumulated_values=filters.accumulated_values, ignore_closing_entries=True, ignore_accumulated_values_for_fy= True)
		
	net_profit_loss = get_net_profit_loss(income, expense, period_list, filters.company)

	data = []
	company_currency = frappe.get_cached_value('Company',  filters.company,  "default_currency")
	
	for cash_flow_account in cash_flow_accounts:
		section_data = []
		data.append({
			"account_name": cash_flow_account['section_header'], 
			"parent_account": None,
			"indent": 0.0, 
			"account": cash_flow_account['section_header']
		})

		if len(data) == 1:
			# add first net income in operations section
			if net_profit_loss:
				net_profit_loss.update({
					"indent": 1, 
					"parent_account": cash_flow_accounts[0]['section_header']
				})
				data.append(net_profit_loss)
				section_data.append(net_profit_loss)

		for account in cash_flow_account['account_types']:
			account_data = get_account_type_based_data(filters.company, 
				account['account_type'], period_list, filters.accumulated_values)
			account_data.update({
				"account_name": account['label'],
				"account": account['label'], 
				"indent": 1,
				"parent_account": cash_flow_account['section_header'],
				"currency": company_currency
			})
			data.append(account_data)
			section_data.append(account_data)

		add_total_row_account(data, section_data, cash_flow_account['section_footer'], 
			period_list, company_currency)

	add_total_row_account(data, data, _("Net Change in Cash"), period_list, company_currency)
	columns = get_columns(filters.periodicity, period_list, filters.accumulated_values, filters.company)

	return columns, data

def get_cash_flow_accounts():
	operation_accounts = {
		"section_name": "Operations",
		"section_footer": _("Net Cash from Operations"),
		"section_header": _("Cash Flow from Operations"),
		"account_types": [
			{"account_type": "Depreciation", "label": _("Depreciation")},
			{"account_type": "Receivable", "label": _("Net Change in Accounts Receivable")},
			{"account_type": "Payable", "label": _("Net Change in Accounts Payable")},
			{"account_type": "Stock", "label": _("Net Change in Inventory")}
		]
	}

	investing_accounts = {
		"section_name": "Investing",
		"section_footer": _("Net Cash from Investing"),
		"section_header": _("Cash Flow from Investing"),
		"account_types": [
			{"account_type": "Fixed Asset", "label": _("Net Change in Fixed Asset")}
		]
	}

	financing_accounts = {
		"section_name": "Financing",
		"section_footer": _("Net Cash from Financing"),
		"section_header": _("Cash Flow from Financing"),
		"account_types": [
			{"account_type": "Equity", "label": _("Net Change in Equity")}
		]
	}

	# combine all cash flow accounts for iteration
	return [operation_accounts, investing_accounts, financing_accounts]

def get_account_type_based_data(company, account_type, period_list, accumulated_values):
	data = {}
	total = 0
	for period in period_list:
		start_date = get_start_date(period, accumulated_values, company)

		amount = get_account_type_based_gl_data(company, start_date, period['to_date'], account_type)
		if amount and account_type == "Depreciation":
			amount *= -1

		total += amount
		data.setdefault(period["key"], amount)

	data["total"] = total
	return data

def get_account_type_based_gl_data(company, start_date, end_date, account_type):
	gl_sum = frappe.db.sql_list("""
		select sum(credit) - sum(debit)
		from `tabGL Entry`
		where company=%s and posting_date >= %s and posting_date <= %s
			and voucher_type != 'Period Closing Voucher'
			and account in ( SELECT name FROM tabAccount WHERE account_type = %s)
	""", (company, start_date, end_date, account_type))

	return gl_sum[0] if gl_sum and gl_sum[0] else 0

def get_start_date(period, accumulated_values, company):
	if not accumulated_values and period.get('from_date'):
		return period['from_date']

	start_date = period["year_start_date"]
	if accumulated_values:
		start_date = get_fiscal_year(period.to_date, company=company)[1]

	return start_date

def add_total_row_account(out, data, label, period_list, currency, consolidated = False):
	total_row = {
		"account_name": "'" + _("{0}").format(label) + "'",
		"account": "'" + _("{0}").format(label) + "'",
		"currency": currency
	}
	for row in data:
		if row.get("parent_account"):
			for period in period_list:
				key = period if consolidated else period['key']
				total_row.setdefault(key, 0.0)
				total_row[key] += row.get(key, 0.0)
			
			total_row.setdefault("total", 0.0)
			total_row["total"] += row["total"]

	out.append(total_row)
	out.append({})