/**

 * Given a GeoJSON object, returns the corresponding bounding box. The bounding

 * box is represented by a two-dimensional array: [[left, bottom], [right,

 * top]], where left is the minimum longitude, bottom is the minimum latitude,

 * right is maximum longitude, and top is the maximum latitude.

 */

d3.geo.bounds = function(feature) {

  var left = Infinity,

      bottom = Infinity,

      right = -Infinity,

      top = -Infinity;

  d3_geo_bounds(feature, function(x, y) {

    if (x < left) left = x;

    if (x > right) right = x;

    if (y < bottom) bottom = y;

    if (y > top) top = y;

  });

  return [[left, bottom], [right, top]];

};

function d3_geo_bounds(o, f) {

  if (o.type in d3_geo_boundsTypes) d3_geo_boundsTypes[o.type](o, f);

}

var d3_geo_boundsTypes = {

  Feature: d3_geo_boundsFeature,

  FeatureCollection: d3_geo_boundsFeatureCollection,

  LineString: d3_geo_boundsLineString,

  MultiLineString: d3_geo_boundsMultiLineString,

  MultiPoint: d3_geo_boundsLineString,

  MultiPolygon: d3_geo_boundsMultiPolygon,

  Point: d3_geo_boundsPoint,

  Polygon: d3_geo_boundsPolygon

};

function d3_geo_boundsFeature(o, f) {

  d3_geo_bounds(o.geometry, f);

}

function d3_geo_boundsFeatureCollection(o, f) {

  for (var a = o.features, i = 0, n = a.length; i < n; i++) {

    d3_geo_bounds(a[i].geometry, f);

  }

}

function d3_geo_boundsLineString(o, f) {

  for (var a = o.coordinates, i = 0, n = a.length; i < n; i++) {

    f.apply(null, a[i]);

  }

}

function d3_geo_boundsMultiLineString(o, f) {

  for (var a = o.coordinates, i = 0, n = a.length; i < n; i++) {

    for (var b = a[i], j = 0, m = b.length; j < m; j++) {

      f.apply(null, b[j]);

    }

  }

}

function d3_geo_boundsMultiPolygon(o, f) {

  for (var a = o.coordinates, i = 0, n = a.length; i < n; i++) {

    for (var b = a[i][0], j = 0, m = b.length; j < m; j++) {

      f.apply(null, b[j]);

    }

  }

}

function d3_geo_boundsPoint(o, f) {

  f.apply(null, o.coordinates);

}

function d3_geo_boundsPolygon(o, f) {

  for (var a = o.coordinates[0], i = 0, n = a.length; i < n; i++) {

    f.apply(null, a[i]);

  }

}