/*
* niViz -- snow profiles visualization
* Copyright (C) 2015 WSL/SLF - Fluelastrasse 11 - 7260 Davos Dorf - Switzerland.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/

/* eslint no-loop-func: [0] */
(function (niviz) {
  'use strict';

  // --- Module Dependencies ---


  /** @module niviz */

  /**
   * Serialize data into CSV format
   *
   * @class CSV
   * @constructor
   */
  var CSV = {};

  // Extract all parameters currently displayed from a Meteograph object.
  // Eliminate all duplicates (may occur when using grouped parameters).
  function uniqueparams (data) {
    var parameters = [];

    // Get the parameters on display
    data.parameters.forEach(function (parameter) {
      data.curves.forEach(function (curve) {
        if (curve.name === parameter) {
          curve.parameters.forEach(function (p) {
            if (parameters.indexOf(p) === -1) parameters.push(p);
          });
        }
      });
    });

    return parameters;
  }

  // For all parameters in the parameters array extract all values
  // in the currently displayed window of the Meteograph object.
  function extract (data, parameters) {
    var meteo = data.data.data, start = 0, end = meteo.length - 1, i, result = '';

    if (data.$indices) {
      start = data.$indices.start;
      end   = data.$indices.end;
    }

    for (i = start; i <= end; ++i) {
      result += meteo[i].timestamp.format('YYYY-MM-DDTHH:mm:ss');

      parameters.forEach(function (p) {
        if (meteo[i][p]) {
          result += ',' + meteo[i][p];
        } else {
          result += ',-999';
        }
      });

      result += '\n';
    }

    return result;
  }

  /**
   * Serialize Meteograph object
   *
   * @method serialize
   * @static
   *
   * @param {Meteograph} data The input data.
   *
   * @returns {String} The serialized result.
   */
  CSV.serialize = function (data) {
    var result;

    if (data.parameters) {
      var parameters = uniqueparams(data);

      result = 'date,' + parameters.join(',') + '\n'; // print header
      result += extract(data, parameters); // print body
    }

    return result;
  };

  // --- Module Exports ---
  niviz.CSV = CSV;

}(niviz));