index.js

/* scroll down to "WEATHER APP MAIN CODE" to see the source code */

/* SKYCONS
 * "colored" version by https://github.com/maxdow/skycons
========================================================= */
(function (global) {
  "use strict";

  /* Set up a RequestAnimationFrame shim so we can animate efficiently FOR
   * GREAT JUSTICE. */
  var requestInterval, cancelInterval;

  (function () {
    var raf = global.requestAnimationFrame ||
      global.webkitRequestAnimationFrame ||
      global.mozRequestAnimationFrame ||
      global.oRequestAnimationFrame ||
      global.msRequestAnimationFrame,
      caf = global.cancelAnimationFrame ||
        global.webkitCancelAnimationFrame ||
        global.mozCancelAnimationFrame ||
        global.oCancelAnimationFrame ||
        global.msCancelAnimationFrame;

    if (raf && caf) {
      requestInterval = function (fn, delay) {
        var handle = { value: null };

        function loop() {
          handle.value = raf(loop);
          fn();
        }

        loop();
        return handle;
      };

      cancelInterval = function (handle) {
        caf(handle.value);
      };
    }

    else {
      requestInterval = setInterval;
      cancelInterval = clearInterval;
    }
  }());

  /* Catmull-rom spline stuffs. */
  /*
  function upsample(n, spline) {
    var polyline = [],
        len = spline.length,
        bx  = spline[0],
        by  = spline[1],
        cx  = spline[2],
        cy  = spline[3],
        dx  = spline[4],
        dy  = spline[5],
        i, j, ax, ay, px, qx, rx, sx, py, qy, ry, sy, t;

    for(i = 6; i !== spline.length; i += 2) {
      ax = bx;
      bx = cx;
      cx = dx;
      dx = spline[i    ];
      px = -0.5 * ax + 1.5 * bx - 1.5 * cx + 0.5 * dx;
      qx =        ax - 2.5 * bx + 2.0 * cx - 0.5 * dx;
      rx = -0.5 * ax            + 0.5 * cx           ;
      sx =                   bx                      ;

      ay = by;
      by = cy;
      cy = dy;
      dy = spline[i + 1];
      py = -0.5 * ay + 1.5 * by - 1.5 * cy + 0.5 * dy;
      qy =        ay - 2.5 * by + 2.0 * cy - 0.5 * dy;
      ry = -0.5 * ay            + 0.5 * cy           ;
      sy =                   by                      ;

      for(j = 0; j !== n; ++j) {
        t = j / n;

        polyline.push(
          ((px * t + qx) * t + rx) * t + sx,
          ((py * t + qy) * t + ry) * t + sy
        );
      }
    }

    polyline.push(
      px + qx + rx + sx,
      py + qy + ry + sy
    );

    return polyline;
  }

  function downsample(n, polyline) {
    var len = 0,
        i, dx, dy;

    for(i = 2; i !== polyline.length; i += 2) {
      dx = polyline[i    ] - polyline[i - 2];
      dy = polyline[i + 1] - polyline[i - 1];
      len += Math.sqrt(dx * dx + dy * dy);
    }

    len /= n;

    var small = [],
        target = len,
        min = 0,
        max, t;

    small.push(polyline[0], polyline[1]);

    for(i = 2; i !== polyline.length; i += 2) {
      dx = polyline[i    ] - polyline[i - 2];
      dy = polyline[i + 1] - polyline[i - 1];
      max = min + Math.sqrt(dx * dx + dy * dy);

      if(max > target) {
        t = (target - min) / (max - min);

        small.push(
          polyline[i - 2] + dx * t,
          polyline[i - 1] + dy * t
        );

        target += len;
      }

      min = max;
    }

    small.push(polyline[polyline.length - 2], polyline[polyline.length - 1]);

    return small;
  }
  */

  /* Define skycon things. */
  /* FIXME: I'm *really really* sorry that this code is so gross. Really, I am.
   * I'll try to clean it up eventually! Promise! */
  var KEYFRAME = 500,
    STROKE = 0.08,
    TAU = 2.0 * Math.PI,
    TWO_OVER_SQRT_2 = 2.0 / Math.sqrt(2);

  function circle(ctx, x, y, r) {
    ctx.beginPath();
    ctx.arc(x, y, r, 0, TAU, false);
    ctx.fill();
  }

  function line(ctx, ax, ay, bx, by) {
    ctx.beginPath();
    ctx.moveTo(ax, ay);
    ctx.lineTo(bx, by);
    ctx.stroke();
  }

  function puff(ctx, t, cx, cy, rx, ry, rmin, rmax) {
    var c = Math.cos(t * TAU),
      s = Math.sin(t * TAU);

    rmax -= rmin;

    circle(
      ctx,
      cx - s * rx,
      cy + c * ry + rmax * 0.5,
      rmin + (1 - c * 0.5) * rmax
    );
  }

  function puffs(ctx, t, cx, cy, rx, ry, rmin, rmax) {
    var i;

    for (i = 5; i--;)
      puff(ctx, t + i / 5, cx, cy, rx, ry, rmin, rmax);
  }

  function cloud(ctx, t, cx, cy, cw, s, color) {
    t /= 30000;

    var a = cw * 0.21,
      b = cw * 0.12,
      c = cw * 0.24,
      d = cw * 0.28;

    ctx.fillStyle = color.cloud || color;
    puffs(ctx, t, cx, cy, a, b, c, d);

    ctx.globalCompositeOperation = 'destination-out';
    puffs(ctx, t, cx, cy, a, b, c - s, d - s);
    ctx.globalCompositeOperation = 'source-over';
  }

  function sun(ctx, t, cx, cy, cw, s, color) {
    t /= 120000;

    var a = cw * 0.25 - s * 0.5,
      b = cw * 0.32 + s * 0.5,
      c = cw * 0.50 - s * 0.5,
      i, p, cos, sin;

    ctx.strokeStyle = color.sun || color;
    ctx.lineWidth = s;
    ctx.lineCap = "round";
    ctx.lineJoin = "round";

    ctx.beginPath();
    ctx.arc(cx, cy, a, 0, TAU, false);
    ctx.stroke();

    for (i = 8; i--;) {
      p = (t + i / 8) * TAU;
      cos = Math.cos(p);
      sin = Math.sin(p);
      line(ctx, cx + cos * b, cy + sin * b, cx + cos * c, cy + sin * c);
    }
  }

  function moon(ctx, t, cx, cy, cw, s, color) {
    t /= 15000;

    var a = cw * 0.29 - s * 0.5,
      b = cw * 0.05,
      c = Math.cos(t * TAU),
      p = c * TAU / -16;

    ctx.strokeStyle = color.moon || color;
    ctx.lineWidth = s;
    ctx.lineCap = "round";
    ctx.lineJoin = "round";

    cx += c * b;

    ctx.beginPath();
    ctx.arc(cx, cy, a, p + TAU / 8, p + TAU * 7 / 8, false);
    ctx.arc(cx + Math.cos(p) * a * TWO_OVER_SQRT_2, cy + Math.sin(p) * a * TWO_OVER_SQRT_2, a, p + TAU * 5 / 8, p + TAU * 3 / 8, true);
    ctx.closePath();
    ctx.stroke();
  }

  function rain(ctx, t, cx, cy, cw, s, color) {
    t /= 1350;

    var a = cw * 0.16,
      b = TAU * 11 / 12,
      c = TAU * 7 / 12,
      i, p, x, y;

    ctx.fillStyle = color.rain || color;

    for (i = 4; i--;) {
      p = (t + i / 4) % 1;
      x = cx + ((i - 1.5) / 1.5) * (i === 1 || i === 2 ? -1 : 1) * a;
      y = cy + p * p * cw;
      ctx.beginPath();
      ctx.moveTo(x, y - s * 1.5);
      ctx.arc(x, y, s * 0.75, b, c, false);
      ctx.fill();
    }
  }

  function sleet(ctx, t, cx, cy, cw, s, color) {
    t /= 750;

    var a = cw * 0.1875,
      b = TAU * 11 / 12,
      c = TAU * 7 / 12,
      i, p, x, y;

    ctx.strokeStyle = color.rain || color;
    ctx.lineWidth = s * 0.5;
    ctx.lineCap = "round";
    ctx.lineJoin = "round";

    for (i = 4; i--;) {
      p = (t + i / 4) % 1;
      x = Math.floor(cx + ((i - 1.5) / 1.5) * (i === 1 || i === 2 ? -1 : 1) * a) + 0.5;
      y = cy + p * cw;
      line(ctx, x, y - s * 1.5, x, y + s * 1.5);
    }
  }

  function snow(ctx, t, cx, cy, cw, s, color) {
    t /= 3000;

    var a = cw * 0.16,
      b = s * 0.75,
      u = t * TAU * 0.7,
      ux = Math.cos(u) * b,
      uy = Math.sin(u) * b,
      v = u + TAU / 3,
      vx = Math.cos(v) * b,
      vy = Math.sin(v) * b,
      w = u + TAU * 2 / 3,
      wx = Math.cos(w) * b,
      wy = Math.sin(w) * b,
      i, p, x, y;

    ctx.strokeStyle = color.snow || color;
    ctx.lineWidth = s * 0.5;
    ctx.lineCap = "round";
    ctx.lineJoin = "round";

    for (i = 4; i--;) {
      p = (t + i / 4) % 1;
      x = cx + Math.sin((p + i / 4) * TAU) * a;
      y = cy + p * cw;

      line(ctx, x - ux, y - uy, x + ux, y + uy);
      line(ctx, x - vx, y - vy, x + vx, y + vy);
      line(ctx, x - wx, y - wy, x + wx, y + wy);
    }
  }

  function fogbank(ctx, t, cx, cy, cw, s, color) {
    t /= 30000;

    var a = cw * 0.21,
      b = cw * 0.06,
      c = cw * 0.21,
      d = cw * 0.28;

    ctx.fillStyle = color.fogbank || color;
    puffs(ctx, t, cx, cy, a, b, c, d);

    ctx.globalCompositeOperation = 'destination-out';
    puffs(ctx, t, cx, cy, a, b, c - s, d - s);
    ctx.globalCompositeOperation = 'source-over';
  }

  /*
  var WIND_PATHS = [
        downsample(63, upsample(8, [
          -1.00, -0.28,
          -0.75, -0.18,
          -0.50,  0.12,
          -0.20,  0.12,
          -0.04, -0.04,
          -0.07, -0.18,
          -0.19, -0.18,
          -0.23, -0.05,
          -0.12,  0.11,
           0.02,  0.16,
           0.20,  0.15,
           0.50,  0.07,
           0.75,  0.18,
           1.00,  0.28
        ])),
        downsample(31, upsample(16, [
          -1.00, -0.10,
          -0.75,  0.00,
          -0.50,  0.10,
          -0.25,  0.14,
           0.00,  0.10,
           0.25,  0.00,
           0.50, -0.10,
           0.75, -0.14,
           1.00, -0.10
        ]))
      ];
  */

  var WIND_PATHS = [
    [
      -0.7500, -0.1800, -0.7219, -0.1527, -0.6971, -0.1225,
      -0.6739, -0.0910, -0.6516, -0.0588, -0.6298, -0.0262,
      -0.6083, 0.0065, -0.5868, 0.0396, -0.5643, 0.0731,
      -0.5372, 0.1041, -0.5033, 0.1259, -0.4662, 0.1406,
      -0.4275, 0.1493, -0.3881, 0.1530, -0.3487, 0.1526,
      -0.3095, 0.1488, -0.2708, 0.1421, -0.2319, 0.1342,
      -0.1943, 0.1217, -0.1600, 0.1025, -0.1290, 0.0785,
      -0.1012, 0.0509, -0.0764, 0.0206, -0.0547, -0.0120,
      -0.0378, -0.0472, -0.0324, -0.0857, -0.0389, -0.1241,
      -0.0546, -0.1599, -0.0814, -0.1876, -0.1193, -0.1964,
      -0.1582, -0.1935, -0.1931, -0.1769, -0.2157, -0.1453,
      -0.2290, -0.1085, -0.2327, -0.0697, -0.2240, -0.0317,
      -0.2064, 0.0033, -0.1853, 0.0362, -0.1613, 0.0672,
      -0.1350, 0.0961, -0.1051, 0.1213, -0.0706, 0.1397,
      -0.0332, 0.1512, 0.0053, 0.1580, 0.0442, 0.1624,
      0.0833, 0.1636, 0.1224, 0.1615, 0.1613, 0.1565,
      0.1999, 0.1500, 0.2378, 0.1402, 0.2749, 0.1279,
      0.3118, 0.1147, 0.3487, 0.1015, 0.3858, 0.0892,
      0.4236, 0.0787, 0.4621, 0.0715, 0.5012, 0.0702,
      0.5398, 0.0766, 0.5768, 0.0890, 0.6123, 0.1055,
      0.6466, 0.1244, 0.6805, 0.1440, 0.7147, 0.1630,
      0.7500, 0.1800
    ],
    [
      -0.7500, 0.0000, -0.7033, 0.0195, -0.6569, 0.0399,
      -0.6104, 0.0600, -0.5634, 0.0789, -0.5155, 0.0954,
      -0.4667, 0.1089, -0.4174, 0.1206, -0.3676, 0.1299,
      -0.3174, 0.1365, -0.2669, 0.1398, -0.2162, 0.1391,
      -0.1658, 0.1347, -0.1157, 0.1271, -0.0661, 0.1169,
      -0.0170, 0.1046, 0.0316, 0.0903, 0.0791, 0.0728,
      0.1259, 0.0534, 0.1723, 0.0331, 0.2188, 0.0129,
      0.2656, -0.0064, 0.3122, -0.0263, 0.3586, -0.0466,
      0.4052, -0.0665, 0.4525, -0.0847, 0.5007, -0.1002,
      0.5497, -0.1130, 0.5991, -0.1240, 0.6491, -0.1325,
      0.6994, -0.1380, 0.7500, -0.1400
    ]
  ],
    WIND_OFFSETS = [
      { start: 0.36, end: 0.11 },
      { start: 0.56, end: 0.16 }
    ];

  function leaf(ctx, t, x, y, cw, s, color) {
    var a = cw / 8,
      b = a / 3,
      c = 2 * b,
      d = (t % 1) * TAU,
      e = Math.cos(d),
      f = Math.sin(d);

    ctx.fillStyle = color.leaf || color;
    ctx.strokeStyle = color.leaf || color;
    ctx.lineWidth = s;
    ctx.lineCap = "round";
    ctx.lineJoin = "round";

    ctx.beginPath();
    ctx.arc(x, y, a, d, d + Math.PI, false);
    ctx.arc(x - b * e, y - b * f, c, d + Math.PI, d, false);
    ctx.arc(x + c * e, y + c * f, b, d + Math.PI, d, true);
    ctx.globalCompositeOperation = 'destination-out';
    ctx.fill();
    ctx.globalCompositeOperation = 'source-over';
    ctx.stroke();
  }

  function swoosh(ctx, t, cx, cy, cw, s, index, total, color) {
    t /= 2500;

    var path = WIND_PATHS[index],
      a = (t + index - WIND_OFFSETS[index].start) % total,
      c = (t + index - WIND_OFFSETS[index].end) % total,
      e = (t + index) % total,
      b, d, f, i;

    ctx.strokeStyle = color.cloud || color;
    ctx.lineWidth = s;
    ctx.lineCap = "round";
    ctx.lineJoin = "round";

    if (a < 1) {
      ctx.beginPath();

      a *= path.length / 2 - 1;
      b = Math.floor(a);
      a -= b;
      b *= 2;
      b += 2;

      ctx.moveTo(
        cx + (path[b - 2] * (1 - a) + path[b] * a) * cw,
        cy + (path[b - 1] * (1 - a) + path[b + 1] * a) * cw
      );

      if (c < 1) {
        c *= path.length / 2 - 1;
        d = Math.floor(c);
        c -= d;
        d *= 2;
        d += 2;

        for (i = b; i !== d; i += 2)
          ctx.lineTo(cx + path[i] * cw, cy + path[i + 1] * cw);

        ctx.lineTo(
          cx + (path[d - 2] * (1 - c) + path[d] * c) * cw,
          cy + (path[d - 1] * (1 - c) + path[d + 1] * c) * cw
        );
      }

      else
        for (i = b; i !== path.length; i += 2)
          ctx.lineTo(cx + path[i] * cw, cy + path[i + 1] * cw);

      ctx.stroke();
    }

    else if (c < 1) {
      ctx.beginPath();

      c *= path.length / 2 - 1;
      d = Math.floor(c);
      c -= d;
      d *= 2;
      d += 2;

      ctx.moveTo(cx + path[0] * cw, cy + path[1] * cw);

      for (i = 2; i !== d; i += 2)
        ctx.lineTo(cx + path[i] * cw, cy + path[i + 1] * cw);

      ctx.lineTo(
        cx + (path[d - 2] * (1 - c) + path[d] * c) * cw,
        cy + (path[d - 1] * (1 - c) + path[d + 1] * c) * cw
      );

      ctx.stroke();
    }

    if (e < 1) {
      e *= path.length / 2 - 1;
      f = Math.floor(e);
      e -= f;
      f *= 2;
      f += 2;

      leaf(
        ctx,
        t,
        cx + (path[f - 2] * (1 - e) + path[f] * e) * cw,
        cy + (path[f - 1] * (1 - e) + path[f + 1] * e) * cw,
        cw,
        s,
        color
      );
    }
  }

  var Skycons = function (opts) {
    opts = opts || {};
    this.list = [];
    this.interval = null;
    this.monochrome = typeof (opts.monochrome) === "undefined" ? true : opts.monochrome;
    opts.colors = opts.colors || {};
    this.colors = {
      main: opts.colors.main || "#111",
      moon: opts.colors.moon || "#353545",
      fog: opts.colors.fog || "#CCC",
      fogbank: opts.colors.fogbank || "#AAA",
      cloud: opts.colors.cloud || "#666",
      snow: opts.colors.snow || "#C2EEFF",
      leaf: opts.colors.leaf || "#2C5228",
      rain: opts.colors.rain || "#7FDBFF",
      sun: opts.colors.sun || "#FFDC00"
    };
    if (this.monochrome) {
      this.color = opts.color || this.colors.main;
    } else {
      this.color = this.colors;
    }
    this.resizeClear = !!(opts && opts.resizeClear);
  };

  Skycons.CLEAR_DAY = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h);

    sun(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, color);
  };

  Skycons.CLEAR_NIGHT = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h);

    moon(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, color);
  };

  Skycons.PARTLY_CLOUDY_DAY = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h);

    sun(ctx, t, w * 0.625, h * 0.375, s * 0.75, s * STROKE, color);
    cloud(ctx, t, w * 0.375, h * 0.625, s * 0.75, s * STROKE, color);
  };

  Skycons.PARTLY_CLOUDY_NIGHT = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h);

    moon(ctx, t, w * 0.667, h * 0.375, s * 0.75, s * STROKE, color);
    cloud(ctx, t, w * 0.375, h * 0.625, s * 0.75, s * STROKE, color);
  };

  Skycons.CLOUDY = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h);

    cloud(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, color);
  };

  Skycons.RAIN = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h);

    rain(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
    cloud(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
  };

  Skycons.SLEET = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h);

    sleet(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
    cloud(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
  };

  Skycons.SNOW = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h);

    snow(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
    cloud(ctx, t, w * 0.5, h * 0.37, s * 0.9, s * STROKE, color);
  };

  Skycons.WIND = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h);

    swoosh(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, 0, 2, color);
    swoosh(ctx, t, w * 0.5, h * 0.5, s, s * STROKE, 1, 2, color);
  };

  Skycons.FOG = function (ctx, t, color) {
    var w = ctx.canvas.width,
      h = ctx.canvas.height,
      s = Math.min(w, h),
      k = s * STROKE;

    fogbank(ctx, t, w * 0.5, h * 0.32, s * 0.75, k, color);

    t /= 5000;

    var a = Math.cos((t) * TAU) * s * 0.02,
      b = Math.cos((t + 0.25) * TAU) * s * 0.02,
      c = Math.cos((t + 0.50) * TAU) * s * 0.02,
      d = Math.cos((t + 0.75) * TAU) * s * 0.02,
      n = h * 0.936,
      e = Math.floor(n - k * 0.5) + 0.5,
      f = Math.floor(n - k * 2.5) + 0.5;

    ctx.strokeStyle = color.fog || color;
    ctx.lineWidth = k;
    ctx.lineCap = "round";
    ctx.lineJoin = "round";

    line(ctx, a + w * 0.2 + k * 0.5, e, b + w * 0.8 - k * 0.5, e);
    line(ctx, c + w * 0.2 + k * 0.5, f, d + w * 0.8 - k * 0.5, f);
  };

  Skycons.prototype = {
    _determineDrawingFunction: function (draw) {
      if (typeof draw === "string")
        draw = Skycons[draw.toUpperCase().replace(/-/g, "_")] || null;

      return draw;
    },
    add: function (el, draw) {
      var obj;

      if (typeof el === "string")
        el = document.getElementById(el);

      // Does nothing if canvas name doesn't exists
      if (el === null)
        return;

      draw = this._determineDrawingFunction(draw);

      // Does nothing if the draw function isn't actually a function
      if (typeof draw !== "function")
        return;

      obj = {
        element: el,
        context: el.getContext("2d"),
        drawing: draw
      };

      this.list.push(obj);
      this.draw(obj, KEYFRAME);
    },
    set: function (el, draw) {
      var i;

      if (typeof el === "string")
        el = document.getElementById(el);

      for (i = this.list.length; i--;)
        if (this.list[i].element === el) {
          this.list[i].drawing = this._determineDrawingFunction(draw);
          this.draw(this.list[i], KEYFRAME);
          return;
        }

      this.add(el, draw);
    },
    remove: function (el) {
      var i;

      if (typeof el === "string")
        el = document.getElementById(el);

      for (i = this.list.length; i--;)
        if (this.list[i].element === el) {
          this.list.splice(i, 1);
          return;
        }
    },
    draw: function (obj, time) {
      var canvas = obj.context.canvas;

      if (this.resizeClear)
        canvas.width = canvas.width;

      else
        obj.context.clearRect(0, 0, canvas.width, canvas.height);

      obj.drawing(obj.context, time, this.color);
    },
    play: function () {
      var self = this;

      this.pause();
      this.interval = requestInterval(function () {
        var now = Date.now(),
          i;

        for (i = self.list.length; i--;)
          self.draw(self.list[i], now);
      }, 1000 / 60);
    },
    pause: function () {
      var i;

      if (this.interval) {
        cancelInterval(this.interval);
        this.interval = null;
      }
    }
  };

  global.Skycons = Skycons;
}(this));
/* END OF SKYCONS
================= */






/* WEATHER APP MAIN CODE
======================== */
var $container = $(".container");
var $icons = $(".icon");
var $summary = $("#summary");
var $right = $(".right");
var $location = $("#location");
var $day = $(".day");
var $temperature = $(".temperature");
var $temp = $(".temp");
var $wind = $("#wind");
var $humidity = $("#humidity");

/* generate icons
 * http://darkskyapp.github.io/skycons */
var skycons = new Skycons({
  "monochrome": false,
  "colors": {
    "main": "white",
    "cloud": "#c1c1c1",
    "moon": "#494960"
  }
});

// store celsius
var celsiusArr = [];
// store fahrenheit
var fahrenheitArr = [];

// options for getCurrentPosition()
var options = { timeout: 5000 }

/*
 * because of javascript's asynchronous behavior
 * all getJSON() calls must be inside getCurrentPosition() to use "coords"
 * https://www.pluralsight.com/guides/front-end-javascript/introduction-to-asynchronous-javascript
*/

// get the current position & retrive weather information
navigator.geolocation.getCurrentPosition(success, error, options);

// let user insert location
$location.keyup(function (event) {
  // store address from user input
  var address = $location.val();
  // check if "enter" key is pressed & check if input field has text
  if (event.which === 13 & $location.length > 0) {
    // delete aprox location
    $("#aprox").remove();
    // convert address to coords
    var url = "https://maps.googleapis.com/maps/api/geocode/json?address=" + address;
    var coords;
    $.getJSON(url, function (json) {
      console.log(json);
      coords = json.results[0].geometry.location.lat + "," + json.results[0].geometry.location.lng;
      // show formatted address
      address = json.results[0].formatted_address
      address = address
        // remove every words after a comma
        .split(",").shift()
        // remove numbers from address
        .replace(/\d/g, "")
        // remove two or more consecutive capital letters
        .replace(/[A-Z]{2,}/g, "")
        // remove the first space
        .replace(/^\s/, "")
        // remove the last space
        .replace(/\s$/, "");
      // show location
      $location.val(address);
      // auto scale input width
      autoScalingInput($location, 10, 20, 240);
    }).done(function () {
      // delete temperature arrays
      celsiusArr = [];
      fahrenheitArr = [];
      // get weather information
      getWeather(coords);
    });
  }
});

// toggle between celsius and fahrenheit
$temperature.on("click", function () {
  $temp.each(function (i) {
    // check if the current temp is in celsius
    if ($(this).html().search(/°C/g) > -1) {
      // show fahrenheit
      $(this).html(fahrenheitArr[i] + " °F");
    } else {
      // show celsius
      $(this).html(celsiusArr[i] + " °C");
    }
  });
}); // END of "click" listener

// if getCurrentPosition succeed then run success()
function success(position) {
  // store coords using HTML5 geolocation
  var coords = position.coords.latitude + "," + position.coords.longitude;
  // get address
  getAddress(coords);
  // get weather information
  getWeather(coords);
}

// if getCurrentPosition() trow an error then run error()
function error(err) {
  // show error in console
  console.warn("ERROR(${err.code}): ${err.message}");
  // store api url
  var url = "https://ipinfo.io/geo?callback=?";
  // retrive coords based on ip address
  $.getJSON(url, function (json) {
    // log json data
    console.log(json);
    // store address
    var address = json.city + ', ' + json.country;
    address = address
      // remove every words after a comma
      .split(",").shift()
      // remove numbers from address
      .replace(/\d/g, "")
      // remove two or more consecutive capital letters
      .replace(/[A-Z]{2,}/g, "")
      // remove the first space
      .replace(/^\s/, "")
      // remove the last space
      .replace(/\s$/, "");
    // warn the user that the location is approximate
    $right.prepend('<p id="aprox" style="font-size: 1.2em">Aprox location</p>');
    // show location
    $location.val(address);
    // auto scale input width
    autoScalingInput($location, 10, 20, 240);
    // store coords
    var coords = json.loc;
    // get weather information
    getWeather(coords);
  });
}

// get weather information
function getWeather(coords) {
  /* store api url
   * api documentation: https://darksky.net/dev/docs/forecast
   * use JSONP to access data from different server's domain by 
   * adding callback=? at the end of the url */
  var url = "https://api.darksky.net/forecast/a5ea3a75b7361771323e8adc14b09b66/"
    + coords + "?exclude=minutely,hourly,flags" + "&units=si" + "&callback=?";
  // json call to get weather information
  $.getJSON(url, function (json) {
    // log json data
    console.log(json);
    // get current date
    var time = new TimeConverter(json.currently.time);
    $day.first().html(time.day + " " + time.dayNum);
    // get current celsius
    var celsius = json.currently.temperature;
    // convert celsius to fahrenheit and store both in arrays
    storeTemp(celsius);
    // show celsius by default
    $temp.first().html(celsiusArr[0] + " °C");
    // get wind
    $wind.html(json.currently.windSpeed + 'm/s');
    // get humidity
    var humidity = Math.round(json.currently.humidity * 100);
    $humidity.html(humidity + '%');
    // show current weather summary
    $summary.html(json.currently.summary);
    // get current icon
    getIcon(json.currently.icon, $icons[0]);
    // get days of week weather
    for (i = 1; i < $day.length; i++) {
      // date
      time = new TimeConverter(json.daily.data[i].time);
      $($day[i]).html(time.dayShort + " " + time.dayNum);
      // icon
      getIcon(json.daily.data[i].icon, $icons[i]);
      // temp
      celsius = (json.daily.data[i].temperatureMax + json.daily.data[i].temperatureMin) / 2;
      storeTemp(celsius);
      $($temp[i]).html(celsiusArr[i] + " °C");
    }
    // set icons width and height
    $icons.each(function () {
      this.width = 128;
      this.height = 128;
    });
    // start icons animation
    skycons.play();
  }).done(function () {
    /* when json call is finished
     * display the app */
    $container.css("display", "block");
  }); // END of getJSON() dark sky api
} // END of getWeather()

// get address using google maps geocoding api
function getAddress(coords) {
  var url = "https://maps.googleapis.com/maps/api/geocode/json?latlng=" + coords;
  $.getJSON(url, function (json) {
    console.log(json);
    var address = json.results[1].formatted_address;
    address = address
      // remove every words after a comma
      .split(",").shift()
      // remove numbers from address
      .replace(/\d/g, "")
      // remove two or more consecutive capital letters
      .replace(/[A-Z]{2,}/g, "")
      // remove the first space
      .replace(/^\s/, "")
      // remove the last space
      .replace(/\s$/, "");
    // show location
    $location.val(address);
    // auto scale input width
    autoScalingInput($location, 10, 20, 240);
  });
}

// https://stackoverflow.com/questions/847185/convert-a-unix-timestamp-to-time-in-javascript
function TimeConverter(UNIX_timestamp) {
  var date = new Date(UNIX_timestamp * 1000);
  var week = ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"];
  var weekShort = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"];
  this.day = week[date.getDay()];
  this.dayNum = date.getDate();
  this.dayShort = weekShort[date.getDay()];
}

// convert celsius to fahrenheit and store both in arrays
function storeTemp(celsius) {
  celsius = Math.round(celsius);
  celsiusArr.push(celsius);
  var fahrenheit = Math.round((celsius * 9) / 5 + 32);
  fahrenheitArr.push(fahrenheit);
}

// get weather icons
// http://darkskyapp.github.io/skycons/
function getIcon(icon, iconID) {
  var weather = ["clear-day", "clear-night", "rain", "snow", "sleet", "wind", "fog", "cloudy", "partly-cloudy-day", "partly-cloudy-night"];
  var currentIcon = icon.replace(/-/g, '_').toUpperCase();
  return skycons.set(iconID, Skycons[currentIcon]);
}

/* auto scaling <input> to width of value
 * https://stackoverflow.com/a/22423199 */
function autoScalingInput(elements, offset, min, max) {

  // Initialize parameters
  offset = offset || 0;
  min = min || 0;
  max = max || Infinity;
  elements.each(function () {
    var element = $(this);

    // Add element to measure pixel length of text
    var id = btoa(Math.floor(Math.random() * Math.pow(2, 64)));
    var tag = $('<span id="' + id + '">' + element.val() + '</span>').css({
      'display': 'none',
      'font-family': element.css('font-family'),
      'font-size': element.css('font-size'),
    }).appendTo('body');

    // Adjust element width on keydown
    function update() {

      // Give browser time to add current letter
      setTimeout(function () {

        // Prevent whitespace from being collapsed
        tag.html(element.val().replace(/ /g, '&nbsp'));

        // Clamp length and prevent text from scrolling
        var size = Math.max(min, Math.min(max, tag.width() + offset));
        if (size < max)
          element.scrollLeft(0);

        // Apply width to element
        element.width(size);
      }, 0);
    };
    update();
    element.keydown(update);
  });
}