const goalsFor = {};
const goalsAgainst = {};

const Diagram = {
    clear: () => d3.select('svg').selectAll("*").remove(),

    swapGroupArcs: (chords, i, j) => {
        if (i < 0 || j < 0 || i === j) {
            return chords;
        }

        // Determine which arc is closer to 0, so earlier arc always swaps with later.
        const f = (chords.groups[i].endAngle < chords.groups[j].endAngle ? i : j);
        const s = (chords.groups[i].endAngle < chords.groups[j].endAngle ? j : i);

        const fst = Object.assign({}, chords.groups[f]);
        const snd = Object.assign({}, chords.groups[s]);

        const fstAngle = fst.endAngle - fst.startAngle;
        const sndAngle = snd.endAngle - snd.startAngle;
        const offsetAngle = sndAngle - fstAngle;

        // Bring first forward.
        chords.groups[f].startAngle = snd.endAngle - fstAngle;
        chords.groups[f].endAngle = snd.endAngle;
        chords.groups[f].index = snd.index;

        // Bring second back.
        chords.groups[s].startAngle = fst.startAngle;
        chords.groups[s].endAngle = fst.startAngle + sndAngle;
        chords.groups[s].index = fst.index;

        // Bump other groups forward.
        for (let ii = f + 1; ii < s; ii++) {
            chords.groups[ii].startAngle += offsetAngle;
            chords.groups[ii].endAngle += offsetAngle;
        }

        // Swap array positions.
        const tmp = chords.groups[f]
        chords.groups[f] = chords.groups[s];
        chords.groups[s] = tmp;

        return chords;
    },

    swapGroups: (data, eventIndex, chords, i, j) => {
        Diagram.swapGroupArcs(chords, i, j);
        Matrices.swapIndices(data.tourneys[eventIndex].teams, i, j);
        return chords;
    },

    getCountryName: (data, eventIndex, n) => {
        const countryId = data.teams[data.tourneys[eventIndex].teams[n]];
        return data.countries[countryId].n;
    },

    getPopulation: (data, eventIndex, n) => {
        const teamId = data.tourneys[eventIndex].teams[n];
        return data.countries[data.teams[teamId]].p;
    },

    getGoalsFor: (data, eventIndex, n) => {
        const teamId = data.tourneys[eventIndex].teams[n];

        if (goalsFor[teamId] === undefined) {
            goalsFor[teamId] = data.tourneys[eventIndex].games.reduce((acc, v) => {

                if (v.t1 === teamId) {
                    return acc + v.s1 + v.se1 + v.sp1;
                }

                if (v.t2 === teamId) {
                    return acc + v.s2 + v.se2 + v.sp2;
                }

                return acc;
            }, 0);
        }

        return goalsFor[teamId];
    },

    getGoalsAgainst: (data, eventIndex, n) => {
        const teamId = data.tourneys[eventIndex].teams[n];

        if (goalsAgainst[teamId] === undefined) {
            goalsAgainst[teamId] = data.tourneys[eventIndex].games.reduce((acc, v) => {

                if (v.t2 === teamId) {
                    return acc + v.s1 + v.se1 + v.sp1;
                }

                if (v.t1 === teamId) {
                    return acc + v.s2 + v.se2 + v.sp2;
                }

                return acc;
            }, 0);
        }

        return goalsAgainst[teamId];
    },

    build: (data, eventIndex, metaMatrix, chordMatrix) => {
        const svg = d3.select("svg"),
            width = +svg.attr("width"),
            height = +svg.attr("height"),
            outerArcThickness = 5,
            outerRadius = Math.min(width, height) * 0.5 - 125,
            innerRadius = outerRadius - outerArcThickness;

        const chords = d3.chord()
            .padAngle(0.05)
            .call(null, chordMatrix);

        const sortedChords = Sorter.sort(chords, 0, chords.groups.length - 1,
            // Diagram.getCountryName.bind(null, data, eventIndex),
            // Diagram.getGoalsFor.bind(null, data, eventIndex),
            // Diagram.getGoalsAgainst.bind(null, data, eventIndex),
            Diagram.getPopulation.bind(null, data, eventIndex),
            Diagram.swapGroups.bind(null, data, eventIndex));

        const arc = d3.arc()
            .innerRadius(innerRadius)
            .outerRadius(outerRadius);

        const ribbon = d3.ribbon()
            .radius(innerRadius);

        // const color = d3.scaleOrdinal(d3.schemeCategory20);
        // const color = d3.scaleOrdinal(d3.schemeCategory10);
        // const color = d3.scaleOrdinal(d3.interpolateCool);
        // const color = d3.scaleSequential(d3.interpolateRainbow);

        const color = d3.scaleLinear().domain([0,10]).range(["red", "blue"]).interpolate(d3.interpolateRgb)

        // const colors = ["#f1eef6","#d4b9da","#c994c7","#df65b0","#e7298a","#ce1256","#91003f"];
        // const colors = ["#ffffcc","#c7e9b4","#7fcdbb","#41b6c4","#1d91c0","#225ea8","#0c2c84"];
        // const colors = ["#7fcdbb","#41b6c4","#1d91c0","#225ea8","#253494","#081d58"];
        // const colors = ["#1B9E77", "#D95F02", "#7570B3", "#E7298A", "#66A61E", "#E6AB02", "#A6761D", "#666666"];
        // const color = i => colors[i % colors.length];

        const g = svg.append("g")
            .attr("transform", "translate(" + width / 2 + "," + height / 2 + ")")
            .datum(sortedChords);

        const group = g.append("g")
            .attr("class", "groups")
          .selectAll("g")
            .data(chords => chords.groups)
          .enter().append("g");

        group.append("path")
            .style("fill", d => color(d.index))
            .style("stroke", d => d3.rgb(color(d.index)).darker())
            .attr("d", arc);

        // g.append("g")
        //     .attr("class", "ribbons")
        //   .selectAll("path")
        //     .data(function(chords) { return chords; })
        //   .enter().append("path")
        //     .attr("d", ribbon)
        //     .style("fill", function(d) { return color(d.target.index); })
        //     .style("stroke", function(d) { return d3.rgb(color(d.target.index)).darker(); })
        //     .attr("class", "ribbon")
        //     // .append("title")
        //     // .text(function(d) {
        //     //     const meta1 = metaMatrix[d.target.index][d.source.index];
        //     //     const meta2 = metaMatrix[d.source.index][d.target.index];
        //     //
        //     //     const g = meta1.game;
        //     //
        //     //     const t1 = lookup.teams[g.t1];
        //     //     const t2 = lookup.teams[g.t2];
        //     //
        //     //     const e1 = g.s1e ? `(+${g.s1e} in extended time)` : '';
        //     //     const e2 = g.s2e ? `(+${g.s2e} in extended time)` : '';
        //     //
        //     //     const p1 = g.s1p ? `(+${g.s1p} in penalties)` : '';
        //     //     const p2 = g.s2p ? `(+${g.s2p} in penalties)` : '';
        //     //
        //     //     return `${t1}: ${g.s1} ${e1} ${p1}\n${t2}: ${g.s2} ${e2} ${p2}`;
        //     // });
        //
        group.append("text")
          .each(function(d) { d.angle = (d.startAngle + d.endAngle) / 2; })
          .attr("dy", ".35em")
          .attr("transform", function(d) {
            return "rotate(" + (d.angle * 180 / Math.PI - 90) + ")"
                + "translate(" + (innerRadius + 26) + ")"
                + (d.angle > Math.PI ? "rotate(180)" : "");
          })
          .style("text-anchor", function(d) { return d.angle > Math.PI ? "end" : null; })
          .text(function(d) {
              // STRANGE EXTENDED TIME CHILE-BRAZIL - FIX BY HAND? IS BECAUE se1 IS SCORE __GOING INTO__ EXTENDED TIME

                const teamId = data.tourneys[eventIndex].teams[d.index];
                const country = data.countries[data.teams[teamId]];
                return data.countries[data.teams[teamId]].n + ' ' + country.p;
          });
    },
};