// Given some transaction data
import {
  identifyTrends,
  isSpecificWeekdayTrendDescription,
  isEveryWeekdayTrendDescription,
} from "teller-js";

const transactions = [
  {
    accountId: "8Ybo8ppEBrHxJM45p7koSvaKQnM341fyMKQwO",
    timestamp: 1586473200000.0,
    amount: 0.01,
    merchantName: "Asda",
    reference: "Asda",
  },
  ...{
    accountId: "8Ybo8ppEBrHxJM45p7koSvaKQnM341fyMKQwO",
    timestamp: 1586300400000.0,
    amount: -60.0,
    merchantName: "201053 53364402 MOBILE-CHANNEL FT",
    reference: "201053 53364402 MOBILE-CHANNEL FT",
  },
];

// Finding Trends
const result = identifyTrends(t);

result.forEach((tr) => {
  const merchant = tr.merchant;
  const trend = tr.trend;
	
  // Checking the type of a trend
  if (isEveryWeekdayTrendDescription(trend)) {
    console.log(`${merchant} transaction happens every day`);
  }

  if (isSpecificWeekdayTrendDescription(trend)) {
    const days = ["mon", "tue", "wed", "thu", "fri", "sat", "sun"];

    console.log(
      `${merchant} transaction happens every ${days[trend.value0.weekday]}`
    );
  }
});

// Making a forecast based on the trend, returning which
// trend ids will happen on each day
const f = forecast(1603580400000.0)(1604188800000.0)(result);

console.log(JSON.stringify(f, null, 2));

/**
 * {
  "days": [
    {
      "dateTimestampMs": 1603497600000,
      "trendIds": [
        "Weekday_[2,6,7]_Transport for London"
      ]
    },
    ...
    {
      "dateTimestampMs": 1604102400000,
      "trendIds": [
        "MonthDay_31_BILL_A",
        "MonthDay_31_BILL_B",
        "MonthDay_31_BILL_C",
        "MonthDay_31_BILL_D",
        "Weekday_[2,6,7]_Transport for London"
      ]
    },
    {
      "dateTimestampMs": 1604188800000,
      "trendIds": [
        "MonthDay_1_Ocado",
        "Weekday_[2,6,7]_Transport for London"
      ]
    }
  ]
}
 */