import _ from "lodash";
import moment from "moment";
import { saveAs } from "file-saver";

const DEFAULT_DATETIME_FORMAT = "YYYY-MM-DDTHH:mm:ssZ";

export function exportSeriesListToCsv(
  seriesList,
  dateTimeFormat = DEFAULT_DATETIME_FORMAT,
  excel = false
) {
  var text = (excel ? "sep=;\n" : "") + "Series;Time;Value\n";
  _.each(seriesList, function(series) {
    _.each(series.datapoints, function(dp) {
      text +=
        series.alias +
        ";" +
        moment(dp[1]).format(dateTimeFormat) +
        ";" +
        dp[0] +
        "\n";
    });
  });
  saveSaveBlob(text, "grafana_data_export.csv");
}

export function exportSeriesListToCsvColumns(
  seriesList,
  dateTimeFormat = DEFAULT_DATETIME_FORMAT,
  excel = false
) {
  var text = (excel ? "sep=;\n" : "") + "Time;";
  // add header
  _.each(seriesList, function(series) {
    text += series.alias + ";";
  });
  text = text.substring(0, text.length - 1);
  text += "\n";

  // process data
  var dataArr = [[]];
  var sIndex = 1;
  _.each(seriesList, function(series) {
    var cIndex = 0;
    dataArr.push([]);
    _.each(series.datapoints, function(dp) {
      dataArr[0][cIndex] = moment(dp[1]).format(dateTimeFormat);
      dataArr[sIndex][cIndex] = dp[0];
      cIndex++;
    });
    sIndex++;
  });

  // make text
  for (var i = 0; i < dataArr[0].length; i++) {
    text += dataArr[0][i] + ";";
    for (var j = 1; j < dataArr.length; j++) {
      text += dataArr[j][i] + ";";
    }
    text = text.substring(0, text.length - 1);
    text += "\n";
  }
  saveSaveBlob(text, "grafana_data_export.csv");
}

export function exportTableDataToCsv(table, excel = false) {
  var text = excel ? "sep=;\n" : "";
  // add header
  _.each(table.columns, function(column) {
    text += (column.title || column.text) + ";";
  });
  text += "\n";
  // process data
  _.each(table.rows, function(row) {
    _.each(row, function(value) {
      text += value + ";";
    });
    text += "\n";
  });
  saveSaveBlob(text, "grafana_data_export.csv");
}

export function saveSaveBlob(payload, fname) {
  var blob = new Blob([payload], { type: "text/csv;charset=utf-8" });
  saveAs(blob, fname);
}