function zigzag_amplitude(d) {
  return d.amplitude;
}

function zigzag_len(d) {
  return d.len;
}

function zigzag_angularFrequency(d) {
  return d.angularFrequency;
}

d3.svg.zigzag = function() {
  var amplitude = zigzag_amplitude,
      len = zigzag_len,
      angularFrequency = zigzag_angularFrequency;

  function zigzag() {
    var A = amplitude.apply(this, arguments),
        l = len.apply(this, arguments),
        ω = angularFrequency.apply(this, arguments) + 1;

    start = -l/2;
    end = l/2;

    step = l/ω;

    var s = "M" + start + ",0"

    for (var i = 1; i<ω; i++)
      s += "L" + (start + i*step) + "," + ((i%2)?A:-A);

    s += "L" + end + ",0"

    return s;
  }

  zigzag.amplitude = function(v) {
    if (!arguments.length) return amplitude;
    amplitude = d3.functor(v);
    return zigzag;
  };

  zigzag.len = function(v) {
    if (!arguments.length) return len;
    len = d3.functor(v);
    return zigzag;
  };

  zigzag.angularFrequency = function(v) {
    if (!arguments.length) return angularFrequency;
    angularFrequency = d3.functor(v);
    return zigzag;
  };

  return zigzag;
};


function getOffset( el ) {
  var _x = 0;
  var _y = 0;
  while( el && !isNaN( el.offsetLeft ) && !isNaN( el.offsetTop ) ) {
    _x += el.offsetLeft - el.scrollLeft;
    _y += el.offsetTop - el.scrollTop;
    el = el.offsetParent;
  }
  return { top: _y, left: _x };
}

var offset = getOffset(document.getElementById('chart'));

var w = window.innerWidth - offset.left,
    h = window.innerHeight - offset.top,
    fill = d3.scale.category20();

var cp = d3.select("#chart").append("div")
.attr("id", "controlpanel");

var btns = cp.append("div")
.attr("class", "btn-group")
.attr("data-toggle", "buttons-radio");

btns.append("button")
.attr("class", "btn active left")
.attr("value", "all")
.text("Alles")
.on("click", update_graph);

btns.append("button")
.attr("class", "btn right")
.attr("value", "mesh")
.text("nur Mesh")
.on("click", update_graph);

cp.append("label")
  .text("Knoten hervorheben:");

cp.append("br");

cp.append("input")
  .on("keyup", function(){show_node(this.value)})
  .on("change", function(){show_node(this.value)});

function show_node(mac) {
  d3.selectAll("#chart .node").classed("marked", false);
  if (mac.length == 0)
    return;

  d3.selectAll("#chart .node").each( function(d) {
    if (d.id == mac) 
      d3.select(this).classed("marked", true);
  })
}

var hashstr = window.location.hash.substring(1);

function update_graph() {
  var value = jQuery(this).val()

    render_graph(value);
}

render_graph("all");

function render_graph(type) {

  d3.select("#chart svg").remove();

  var vis = d3.select("#chart").append("svg")
    .attr("width", w)
    .attr("height", h);



  d3.json("nodes.json", function(json) {
    var force = d3.layout.force()
    .charge(-100)
    .gravity(0.02)
    .friction(0.75)
    .theta(0.1)
    .linkDistance(function (d) { return d.distance; })
    .linkStrength(function (d) { return d.strength; })
    .nodes(json.nodes)
    .links(json.links)
    .size([w, h])
    .start();

    var linkedByIndex = {};

    json.links.forEach(function(d) {
          linkedByIndex[d.source.index + "," + d.target.index] = 1;
      });

    json.links.forEach(function(d) {
          var node, other;

          if (d.source.group == 2) {
            node = d.target;
            other = d.source;
          }

          if (d.target.group == 2) {
            node = d.source;
            other = d.target;
          }
          
          if (node) {
            if (node.uplinks === undefined)
              node.uplinks = new Array();

            node.uplinks.push(other);
          }
      });

  var linkdata = json.links;

  if (type == "mesh")
    linkdata = json.links.filter( function (d) {
      return d.source.group != 2 && d.target.group != 2 &&
      d.source.group != 3 && d.target.group != 3;
    });


  var link = vis.selectAll("line.link")
    .data(linkdata)
    .enter().append("line")
    .attr("class", "link")
    .style("stroke-width", function(d) { return Math.min(1, d.strength * 2); });

  var linklabel = vis.selectAll("g")
    .data(linkdata.filter(function (d) {return d.quality != "TT" && d.quality != "1.000"}))
    .enter()
    .append("g")
    .append("path")
    .attr("d", d3.svg.zigzag().amplitude(function (d) {
          return Math.pow((1 - 1/d.quality), 0.5) * 8;
        }).len(30).angularFrequency(4)
/*
        d3.svg.arc().outerRadius(5).innerRadius(0)
         .startAngle( function (d) {
            return Math.PI/d.quality - Math.PI/2;
          })
         .endAngle( function (d) {
            return -Math.PI/d.quality - Math.PI/2;
          })
          */
        )
    .attr("fill", "transparent")
    .attr("stroke", "#C83771")
    .attr("stroke-width", "1px")

      function isConnected(a, b) {
            return linkedByIndex[a.index + "," + b.index] || linkedByIndex[b.index + "," + a.index] || a.index == b.index;
        }


   function fade(opacity) {
            return function(d) {
                  node.style("stroke-opacity", function(o) {
        var connected = isConnected(d, o);

        if (connected && opacity != 1)
        d3.select(this).classed("highlight", true);
        else
        d3.select(this).classed("highlight", false);

                      thisOpacity = connected ? 1 : opacity;
                      this.setAttribute('fill-opacity', thisOpacity);
                      return thisOpacity;
                  });

                  link.style("stroke-opacity", function(o) {
                        return o.source === d || o.target === d ? 1 : opacity;
                    });
                  linklabel.style("opacity", function(o) {
                        return o.source === d || o.target === d ? 1 : opacity;
                    });
              };
        } 

  function show_node_info(d) {
    if (!(typeof nodeinfo === 'undefined')) 
      nodeinfo.remove();

    nodeinfo = d3.select("#chart").append("div")
      .attr("id", "nodeinfo");

    nodeinfo.append("h1")
      .text(d.name);

    nodeinfo.append("p")
      .text("primary: " + d.id);

    nodeinfo.append("p")
      .text("macs: " + d.macs);

    nodeinfo.append("p")
      .text(d.gps);
  }

  var node = vis.selectAll("svg.node")
    .data(json.nodes.filter(function (d) {
      return type != "mesh" || (d.group != 2 && d.group != 3);
    }))
  .enter().append("g")
    .attr("class", "node")
    .on("mouseover", fade(.2))
    .on("mouseout", fade(1))
    .on("click", show_node_info)
    .call(force.drag);

  node.append("ellipse")
    .attr("rx", function(d) { if (d.group == 3) return 4; else return Math.max(10, d.name.length * 5); })
    .attr("ry", function(d) { if (d.group == 3) return 4; else return 10; })
    .style("fill", function(d) { if (d.group == 3) return fill(d.group); else return ""; })
    .style("stroke", function(d) { return fill(d.group); });

  node.append("text")
    .attr("text-anchor", "middle")
    .attr("y", "4px")
    .text(function(d) { if (d.group == 3) return ""; else return d.name; });

  node.append("title")
    .text(function(d) { return d.macs; });

  if (type == "mesh") {
    var uplink_info = node.filter(function (d) {
      if (d.uplinks !== undefined)
        return d.uplinks.length > 0;
      else
        return false;
    })
    .append("g");

    uplink_info.append("path")
      .attr("d","m -2.8850049,-13.182327 c 7.5369165,0.200772 12.1529864,-1.294922 12.3338513,-10.639456 l 2.2140476,1.018191 -3.3137621,-5.293097 -3.2945999,5.20893 2.4339957,-0.995747 c -0.4041883,5.76426 -1.1549641,10.561363 -10.3735326,10.701179 z")
      .style("fill", "#333");

    uplink_info.append("text")
      .attr("text-anchor", "middle")
      .attr("y", 3 - 20)
      .text(function (d) {return d.uplinks.length});
  }

  force.on("tick", function() {
    link.attr("x1", function(d) { return d.source.x; })
    .attr("y1", function(d) { return d.source.y; })
    .attr("x2", function(d) { return d.target.x; })
    .attr("y2", function(d) { return d.target.y; });

    linklabel
    .attr("transform", function(d) { 
      π = Math.PI;
      Δx = d.source.x - d.target.x;
      Δy = d.source.y - d.target.y;
      m = Δy/Δx;
      α = Math.atan(m);
      α += Δx<0?π:0;
      sin = Math.sin(α);
      cos = Math.cos(α);
      x = (Math.min(d.source.x, d.target.x) + Math.abs(Δx) / 2)
      y = (Math.min(d.source.y, d.target.y) + Math.abs(Δy) / 2)
      return "matrix(" + [cos, sin, -sin, cos, x, y].join(",") + ")";
    });

  node.attr("transform", function(d) { return "translate(" + d.x + "," + d.y + ")"; });
  });

  if (hashstr.length != 0)
    show_node(hashstr);
  });

}