@flumens/bigu/src/GridRefParser/IE.js

British Isles GridRef Utils

import GridRefParser from './GridRefParser';
import OSIRef from '../OSIRef';

/**
 * @constructor
 */
let GridRefParserIE = function() {};

GridRefParserIE.prototype = new GridRefParser();
GridRefParserIE.prototype.constructor = GridRefParserIE;
GridRefParserIE.prototype.country = 'IE';
GridRefParserIE.prototype.NationalRef = OSIRef;

GridRefParserIE.gridLetter = {
  A: [0,4],
  B: [1,4],
  C: [2,4],
  D: [3,4],
  F: [0,3],
  G: [1,3],
  H: [2,3],
  J: [3,3],
  L: [0,2],
  M: [1,2],
  N: [2,2],
  O: [3,2],
  Q: [0,1],
  R: [1,1],
  S: [2,1],
  T: [3,1],
  V: [0,0],
  W: [1,0],
  X: [2,0],
  Y: [3,0]};

/**
 *
 * @param {string} rawGridRef
 * @throws Error
 */
GridRefParserIE.prototype.parse = function(rawGridRef) {
  var trimmedLocality = rawGridRef.replace(/[\[\]\s\t\.-]+/g, '').toUpperCase();

  if (/[ABCDEFGHIJKLMNPQRSTUVWXYZ]$/.test(trimmedLocality)) {
    // tetrad or quadrant

    if (GridRefParser.quadrantOffsets.hasOwnProperty(trimmedLocality.substr(trimmedLocality.length - 2))) {
      this.quadrantCode = trimmedLocality.substr(trimmedLocality.length - 2);
      trimmedLocality = trimmedLocality.substr(0, trimmedLocality.length - 2);
    } else {
      this.tetradLetter = trimmedLocality.substr(trimmedLocality.length - 1);
      trimmedLocality = trimmedLocality.substr(0, trimmedLocality.length - 1);
    }
  }

  this.parse_gr_string_without_tetrads(trimmedLocality);

  if (this.length > 0) {
    if (this.tetradLetter || this.quadrantCode) {
      // tetrad or quadrant suffix

      if (this.tetradLetter) {
        this.preciseGridRef = this.hectad + this.tetradLetter;
        this.tetrad = this.preciseGridRef;
        this.length = 2000; // 2km square
        this.osRef.x += GridRefParser.tetradOffsets[this.tetradLetter][0];
        this.osRef.y += GridRefParser.tetradOffsets[this.tetradLetter][1];
      } else {
        // quadrant
        this.preciseGridRef = this.hectad + this.quadrantCode;
        this.quadrant = this.preciseGridRef;
        this.length = 5000; // 5km square
        this.osRef.x += GridRefParser.quadrantOffsets[this.quadrantCode][0];
        this.osRef.y += GridRefParser.quadrantOffsets[this.quadrantCode][1];
      }
    } else {
      this.preciseGridRef = trimmedLocality;

      if (this.length <= 1000) {
        // calculate tetrad for precise gridref
        this.set_tetrad();
      }
    }
  } else {
    this.error = true;
    this.errorMessage = "Irish grid reference format not understood. ('" + rawGridRef + "')";
  }
};

GridRefParserIE.prototype.parse_well_formed = GridRefParserIE.prototype.parse;

GridRefParserIE._IE_GRID_LETTERS = 'VQLFAWRMGBXSNHCYTOJD';

/**
 *
 * @param {string} gridRef nn/nnnn or [A-Z]nnnn or [A-Z]/nnnn (no other punctuation by this point), all upper-case
 * @return boolean
 */
GridRefParserIE.prototype.parse_gr_string_without_tetrads = function(gridRef) {
  var x, y, ref, char;

  if (/^\d{2}\/(?:\d\d){1,5}$/.test(gridRef)) {
    // nn/nnnn etc.
    // regex used to avoid matching oddly malformed refs, such as "32/SO763520"

    x = parseInt(gridRef.charAt(0), 10);
    y = parseInt(gridRef.charAt(1), 10);

    if (x > 3 || y > 4) {
      Logger("bad grid square, ref='" + gridRef + "' (Ireland)");
      this.length = 0;
      return false;
    }

    ref = gridRef.substr(3);
    char = GridRefParserIE._IE_GRID_LETTERS.charAt((x * 5) + y);

    x *= 100000;
    y *= 100000;
  } else {
    // [A-Z]nnnn or [A-Z]/nnnn etc.
    gridRef = gridRef.replace('/', '');

    if (!/^[ABCDFGHJLMNOQRSTVWXY](?:\d\d){1,5}$/.test(gridRef)) {
      this.length = 0;// mark error state
      this.osRef = null;
      return false;
    }

    if (gridRef) {
      char = gridRef.charAt(0);
      var p = GridRefParserIE._IE_GRID_LETTERS.indexOf(char);

      if (p !== -1) {
        x = Math.floor(p / 5) * 100000;
        y = (p % 5) * 100000;
      } else {
        Logger("Bad grid ref grid-letter, ref='" + gridRef + "' (Ireland)");
        this.length = 0; // mark error
        this.osRef = null;
        return false;
      }
    } else {
      Logger('Bad (empty) Irish grid ref');
      this.length = 0; // mark error
      this.osRef = null;
      return false;
    }

    ref = gridRef.substr(1);
  }

  switch (ref.length) {
    case 2:
      this.osRef = new OSIRef(
        x + (ref.charAt(0) * 10000),
        y + (ref.charAt(1) * 10000)
      );
      this.length = 10000; //10 km square
      this.hectad = char + ref;
      break;

    case 4:
      this.osRef = new OSIRef(
        x + Math.floor(ref / 100) * 1000,
        y + (ref % 100) * 1000
      );
      this.length = 1000; //1 km square
      this.hectad = char + ref.charAt(0) + ref.charAt(2);
      break;

    case 6:
      this.osRef = new OSIRef(
        x + Math.floor(ref / 1000) * 100,
        y + (ref % 1000) * 100
      );
      this.length = 100; // 100m square
      this.hectad = char + ref.charAt(0) + ref.charAt(3);
      break;

    case 8:
      this.osRef = new OSIRef(
        x + Math.floor(ref / 10000) * 10,
        y + (ref % 10000) * 10
      );
      this.length = 10; //10m square
      this.hectad = char + ref.charAt(0) + ref.charAt(4);
      break;

    case 10:
      this.osRef = new OSIRef(
        x + Math.floor(ref / 100000),
        y + (ref % 100000)
      );
      this.length = 1; //1m square
      this.hectad = char + ref.charAt(0) + ref.charAt(5);
      break;

    default:
      Logger("Bad grid ref length, ref='" + gridRef + "' (Ireland)");
      this.length = 0;
      this.osRef = null;
      return false;
  }
  return true;
};

export default GridRefParserIE;