export function getItems(data) {
  let filteredData = data.filter((metric) => {
    return metric.Value !== 'nan';
  });

  let transform = filteredData.map((metric) => {
    let date = new Date(metric.Timestamp);
    return {
      ...metric,
      Timestamp: {
        time:
          date.getHours() + ':' + String(date.getMinutes()).padStart(2, '0'),
        date: formatDate(date),
      },
      Value: Math.round(metric.Value),
    };
  });

  let group = transform.reduce(function (rv, x) {
    (rv[x['Sensor']] = rv[x['Sensor']] || []).push(x);
    return rv;
  }, {});

  return Object.keys(group).map((metric) => {
    return {
      name: metric,
      current: group[metric][group[metric].length - 1].Value,
      middle: findAverage(group[metric]),
      min: findMin(group[metric]),
      minDate: findDateOfMin(group[metric]),
      max: findMax(group[metric]),
      maxDate: findDateOfMax(group[metric]),
    };
  });
}

function padTo2Digits(num) {
  return num.toString().padStart(2, '0');
}

function formatDate(date) {
  return [
    padTo2Digits(date.getDate()),
    padTo2Digits(date.getMonth() + 1),
    date.getFullYear(),
  ].join('.');
}

function findAverage(arr) {
  const { length } = arr;
  return Math.round(
    arr.reduce((acc, val) => {
      return acc + val.Value / length;
    }, 0)
  );
}

function findMin(arr) {
  return arr.reduce((min, p) => (p.Value < min ? p.Value : min), arr[0].Value);
}

function findMax(arr) {
  return arr.reduce((max, p) => (p.Value > max ? p.Value : max), arr[0].Value);
}

function findDateOfMin(arr) {
  return arr.reduce((res, obj) => (obj.Value < res.Value ? obj : res))
    .Timestamp;
}

function findDateOfMax(arr) {
  return arr.reduce((res, obj) => (obj.Value > res.Value ? obj : res))
    .Timestamp;
}