// Generated by CoffeeScript 1.10.0
(function() {
  var F_ROTATION_INDEXES, GOSPER_ANGLE, INITIAL_SCALE, ROTATION_INDEXES, data, get_hept_coords, get_hex_data, height, hexes, order, rec, svg, vis, width;

  width = 960;

  height = 500;

  data = [];

  INITIAL_SCALE = height / 2.4;

  GOSPER_ANGLE = Math.acos(5 * Math.sqrt(7) / 14) / Math.PI * 180;

  ROTATION_INDEXES = [0, 120, 0, -120, 0, 0, -120];

  F_ROTATION_INDEXES = [-120, 0, 0, -120, 0, 120, 0];

  svg = d3.select('svg').attr({
    width: width,
    height: height,
    viewBox: (-width / 2) + " " + (-height / 2) + " " + width + " " + height
  });

  vis = svg.append('g');

  get_hept_coords = function(scale, indexes, index_i) {
    var a, coords, flip, i, j, len, r, ref;
    a = scale / Math.sqrt(7);
    r = a / Math.sin(Math.PI / 3);
    coords = [
      {
        x: -a,
        y: r + r / 2
      }, {
        x: a,
        y: r + r / 2
      }, {
        x: 0,
        y: 0
      }, {
        x: -2 * a,
        y: 0
      }, {
        x: -a,
        y: -r - r / 2
      }, {
        x: a,
        y: -r - r / 2
      }, {
        x: 2 * a,
        y: 0
      }
    ];
    flip = false;
    if (index_i > 0) {
      ref = indexes.slice(0, index_i);
      for (j = 0, len = ref.length; j < len; j++) {
        i = ref[j];
        if (!flip && (i === 1 || i === 2 || i === 6)) {
          flip = !flip;
        } else if (flip && (i === 0 || i === 4 || i === 5)) {
          flip = !flip;
        }
      }
    }
    if (flip) {
      coords.reverse();
    }
    return {
      coords: coords[indexes[index_i]],
      flip: flip
    };
  };


  /* Returns the rotation, translation and scale of a certain hexagon described as a base 7 number
   */

  get_hex_data = function(indexes) {
    var f_rotation, hept_coords, i, index, j, len, result, rotation, scale, scale_i, translation;
    rotation = GOSPER_ANGLE * indexes.length;
    f_rotation = 0;
    translation = {
      x: 0,
      y: 0
    };
    scale = 1 / Math.pow(Math.sqrt(7), indexes.length);
    for (i = j = 0, len = indexes.length; j < len; i = ++j) {
      index = indexes[i];
      scale_i = 1 / Math.pow(Math.sqrt(7), i);
      result = get_hept_coords(scale_i, indexes, i);
      hept_coords = result.coords;
      hept_coords = hept_tree_utils.rotate_point(hept_coords, GOSPER_ANGLE * (i + 1));
      hept_coords = hept_tree_utils.rotate_point(hept_coords, f_rotation);
      f_rotation += result.flip ? F_ROTATION_INDEXES[index] : ROTATION_INDEXES[index];
      translation.x += hept_coords.x;
      translation.y += hept_coords.y;
    }
    return {
      rotation: rotation,
      frotation: f_rotation,
      translation: translation,
      scale: scale
    };
  };

  rec = function(order, index) {
    var i, j, results;
    if (order === 0) {
      data.push({
        index: index,
        data: get_hex_data(index)
      });
      return;
    }
    data.push({
      index: index,
      data: get_hex_data(index)
    });
    results = [];
    for (i = j = 0; j <= 6; i = ++j) {
      results.push(rec(order - 1, index.concat([i])));
    }
    return results;
  };

  order = Math.floor(Math.random() * 5);

  rec(order, []);

  vis.append('g').attr({
    transform: "translate(" + (-width / 2 + 50) + ", " + (-height / 2 + 50) + ")"
  }).append('text').text("Order " + order);

  hexes = vis.selectAll('path').data(data);

  hexes.enter().append('path').attr({
    "class": 'hex',
    d: function(d) {
      return hept_tree_utils.hex_generate_svg_path(d.data.scale * INITIAL_SCALE, 0);
    },
    transform: function(d) {
      return "translate(" + (d.data.translation.x * INITIAL_SCALE) + ", " + (d.data.translation.y * INITIAL_SCALE) + ") rotate(" + d.data.rotation + ")";
    }
  });

  data = data.filter(function(d) {
    return d.index.length === order;
  }).sort(function(a, b) {
    return d3.ascending(a.index.join(''), b.index.join(''));
  });

  vis.append('path').attr({
    "class": 'curve',
    d: "M" + data.map(function(d) {
      return [d.data.translation.x * INITIAL_SCALE, d.data.translation.y * INITIAL_SCALE].join(' ');
    }).join('L'),
    fill: 'none',
    stroke: 'steelblue'
  });

}).call(this);