import frappe from 'frappejs';

export default class AccountsReceivablePayable {
  async run(reportType, { date }) {
    const rows = await getReceivablePayable({
      reportType,
      date
    });

    return { rows };
  }
};

async function getReceivablePayable({ reportType = 'Receivable', date }) {
  let entries = [];
  const debitOrCredit = reportType === 'Receivable' ? 'debit' : 'credit';
  const referenceType =
    reportType === 'Receivable' ? 'SalesInvoice' : 'PurchaseInvoice';

  entries = await getLedgerEntries();
  const vouchers = await getVouchers();

  const futureEntries = getFutureEntries();
  const returnEntries = getReturnEntries();
  const pdc = getPDC();

  const validEntries = getValidEntries();

  let data = [];

  for (let entry of validEntries) {
    const { outStandingAmount, creditNoteAmount } = getOutstandingAmount(entry);

    console.log(outStandingAmount);

    if (outStandingAmount > 0.1 / 10) {
      const row = {
        date: entry.date,
        party: entry.party
      };

      // due date / bill date

      row.voucherType = entry.referenceType;
      row.voucherNo = entry.referenceName;

      // bill details

      const invoicedAmount = entry[debitOrCredit] || 0;
      const paidAmount = invoicedAmount - outStandingAmount - creditNoteAmount;

      Object.assign(row, {
        invoicedAmount,
        paidAmount,
        outStandingAmount,
        creditNoteAmount
      });

      // ageing

      data.push(row);
    }
  }

  return data;

  // helpers

  async function getVouchers() {
    return await frappe.db.getAll({
      doctype: referenceType,
      fields: ['name', 'date'],
      filters: {
        submitted: 1
      }
    });
  }

  function getValidEntries() {
    return entries.filter(entry => {
      return (
        entry.date <= date &&
        entry.referenceType === referenceType &&
        entry[debitOrCredit] > 0
      );
    });
  }

  function getOutstandingAmount(entry) {
    let paymentAmount = 0.0,
      creditNoteAmount = 0.0;
    let reverseDebitOrCredit = debitOrCredit === 'debit' ? 'credit' : 'debit';

    for (let e of getEntriesFor(
      entry.party,
      entry.referenceType,
      entry.referenceName
    )) {
      if (e.date <= date) {
        const amount = e[reverseDebitOrCredit] - e[debitOrCredit];

        if (!Object.keys(returnEntries).includes(e.referenceName)) {
          paymentAmount += amount;
        } else {
          creditNoteAmount += amount;
        }
      }
    }

    return {
      outStandingAmount:
        entry[debitOrCredit] -
        entry[reverseDebitOrCredit] -
        paymentAmount -
        creditNoteAmount,
      creditNoteAmount
    };
  }

  function getEntriesFor(party, againstVoucherType, againstVoucher) {
    // TODO
    return [];
  }

  function getFutureEntries() {
    return entries.filter(entry => entry.date > date);
  }

  function getReturnEntries() {
    // TODO
    return {};
  }

  function getPDC() {
    return [];
  }

  async function getLedgerEntries() {
    if (entries.length) {
      return entries;
    }

    const partyType = reportType === 'Receivable' ? 'customer' : 'supplier';
    const partyList = (await frappe.db.getAll({
      doctype: 'Party',
      filters: {
        [partyType]: 1
      }
    })).map(d => d.name);

    return await frappe.db.getAll({
      doctype: 'AccountingLedgerEntry',
      fields: [
        'name',
        'date',
        'account',
        'party',
        'referenceType',
        'referenceName',
        'sum(debit) as debit',
        'sum(credit) as credit'
      ],
      filters: {
        party: ['in', partyList]
      },
      groupBy: ['referenceType', 'referenceName', 'party'],
      orderBy: 'date'
    });
  }
}