import Ember from 'ember';
import d3 from 'd3';
import ENV from 'app-client/config/environment';
import _ from 'lodash/lodash';

export default Ember.Component.extend({

    constants: Ember.inject.service(),
    filter: Ember.inject.service(),

    didInsertElement: function(){
        var self = this;
        var margin = {top: 20, right: 0, bottom: 0, left: 0},
        width = Ember.$("#chart_div").width(),
        height = 600 - margin.top - margin.bottom,
        formatNumber = d3.format(",d"),
        transitioning;

        var x = d3.scale.linear()
            .domain([0, width])
            .range([0, width]);

        var y = d3.scale.linear()
            .domain([0, height])
            .range([0, height]);

        var treemap = d3.layout.treemap()
            .children(function(d, depth) { return depth ? null : d._children; })
            .sort(function(a, b) { return a.value - b.value; })
            .ratio(height / width * 0.5 * (1 + Math.sqrt(5)))
            .round(false);

        var svg = d3.select("#chart_div").append("svg")
            .attr("width", width + margin.left + margin.right)
            .attr("height", height + margin.bottom + margin.top)
            .style("margin-left", -margin.left + "px")
            .style("margin.right", -margin.right + "px")
            .append("g")
            .attr("transform", "translate(" + margin.left + "," + margin.top + ")")
            .style("shape-rendering", "crispEdges");

        var grandparent = svg.append("g")
            .attr("class", "grandparent");

        grandparent.append("rect")
            .attr("y", -margin.top)
            .attr("width", width)
            .attr("height", margin.top);

        grandparent.append("text")
            .attr("x", 6)
            .attr("y", 6 - margin.top)
            .attr("dy", ".75em");

        var baseurl = ENV.rootURL.replace(/\/$/,"")+'/api/v1';
        d3.json(baseurl+"/languages", function(languages) {

            var root = _.cloneDeep(self.constants.LANGUAGES_TREEMAP);

            initialize(root);
            accumulate(root);
            layout(root);
            display(root);

            function initialize(root) {
                root.x = root.y = 0;
                root.dx = width;
                root.dy = height;
                root.depth = 0;
            }

            // Aggregate the values for internal nodes. This is normally done by the
            // treemap layout, but not here because of our custom implementation.
            // We also take a snapshot of the original children (_children) to avoid
            // the children being overwritten when when layout is computed.
            function accumulate(d) {
                d._children = d.children;

                if(d.children) {
                    d.value = d.children.reduce(function(p, v) { return p + accumulate(v); }, 0);
                } else if (_.isArray(d.id)) {
                    d.value = d.id.reduce(function(s,lid) { return s + (languages[lid]?languages[lid]:0); }, 0);
                } else {
                    d.value = languages[d.id]?languages[d.id]:0;
                }

                return d.value;
            }

            // Compute the treemap layout recursively such that each group of siblings
            // uses the same size (1×1) rather than the dimensions of the parent cell.
            // This optimizes the layout for the current zoom state. Note that a wrapper
            // object is created for the parent node for each group of siblings so that
            // the parent’s dimensions are not discarded as we recurse. Since each group
            // of sibling was laid out in 1×1, we must rescale to fit using absolute
            // coordinates. This lets us use a viewport to zoom.
            function layout(d) {
                if (d._children) {
                    treemap.nodes({_children: d._children});
                    d._children.forEach(function(c) {
                        c.x = d.x + c.x * d.dx;
                        c.y = d.y + c.y * d.dy;
                        c.dx *= d.dx;
                        c.dy *= d.dy;
                        c.parent = d;
                        layout(c);
                    });
                }
            }

            function display(d) {
                grandparent
                    .datum(d.parent)
                    .on("click", transition)
                    .select("text")
                    .text(name(d));

                var g1 = svg.insert("g", ".grandparent")
                    .datum(d)
                    .attr("class", "depth");

                var g = g1.selectAll("g")
                    .data(d._children)
                    .enter().append("g");

                g.classed("bla", true)
                    .on("click", selectHandler);

                g.filter(function(d) { return d._children; })
                    .classed("children", true)
                    .on("click", transition);

                g.append("rect")
                    .attr("class", "parent")
                    .call(rect)
                    .append("title")
                    .text(function(d) { return formatNumber(d.value); });

                g.append("text")
                    .attr("dy", ".75em")
                    .text(function(d) { return d.name; })
                    .call(text);

                function transition(d) {
                    if (transitioning || !d) {
                        return;
                    }

                    selectHandler(d);
                    transitioning = true;

                    var g2 = display(d),
                    t1 = g1.transition().duration(750),
                    t2 = g2.transition().duration(750);

                    // Update the domain only after entering new elements.
                    x.domain([d.x, d.x + d.dx]);
                    y.domain([d.y, d.y + d.dy]);

                    // Enable anti-aliasing during the transition.
                    svg.style("shape-rendering", null);

                    // Draw child nodes on top of parent nodes.
                    svg.selectAll(".depth").sort(function(a, b) { return a.depth - b.depth; });

                    // Fade-in entering text.
                    g2.selectAll("text").style("fill-opacity", 0);

                    // Transition to the new view.
                    t1.selectAll("text").call(text).style("fill-opacity", 0);
                    t2.selectAll("text").call(text).style("fill-opacity", 1);
                    t1.selectAll("rect").call(rect);
                    t2.selectAll("rect").call(rect);

                    // Remove the old node when the transition is finished.
                    t1.remove().each("end", function() {
                        svg.style("shape-rendering", "crispEdges");
                        transitioning = false;
                    });
                }

                function selectHandler (d){
                    if (d.id){
                        self.get('filter').set('language', d.id);
                    }
                }

                return g;
            }

            function text(text) {
                text.attr("x", function(d) { return x(d.x) + 6; })
                .attr("y", function(d) { return y(d.y) + 6; });
            }

            function rect(rect) {
                rect.attr("x", function(d) { return x(d.x); })
                    .attr("y", function(d) { return y(d.y); })
                    .attr("width", function(d) { return x(d.x + d.dx) - x(d.x); })
                    .attr("height", function(d) { return y(d.y + d.dy) - y(d.y); })
                    .attr("fill", function(d) { return (d.color || "#bbb"); });
            }

            function name(d) {
                return d.parent ? name(d.parent) + "." + d.name : d.name;
            }

        });

    }

});