Bump Ranking

import { type ChartPoint, d3Curve, defineChart, dot, lineY, rank, select, text } from "@tanstack/charts";
import { motion } from "@tanstack/charts/motion";
import { tooltip } from "@tanstack/charts/tooltip";
import { Chart } from "@tanstack/react-charts/core";
import { useMemo } from "react";

import { scaleLinear, scaleUtc } from "d3-scale";
import { curveBumpX } from "d3-shape";
import { Trophy } from "lucide-react";

import { Card, CardContent, CardDescription, CardFooter, CardHeader, CardTitle } from "@/components/ui/card";

interface BumpDatum {
    industry: string;
    date: Date;
    unemployed: number;
    rank?: number;
}

const motionRenderer = motion({
    initial: "always",
    transition: { type: "spring", stiffness: 170, damping: 18, mass: 1 },
});

const industriesList = ["Trade", "Manufacturing", "Services", "Tech", "Construction"];

function generateDemoData(): BumpDatum[] {
    const results: BumpDatum[] = [];
    const years = [2020, 2021, 2022, 2023, 2024, 2025];

    years.forEach((year) => {
        industriesList.forEach((ind, idx) => {
            const unemployed = 100 + Math.floor(Math.sin(year * 0.4 + idx) * 80 + Math.random() * 40);
            results.push({
                industry: ind,
                date: new Date(Date.UTC(year, 0, 1)),
                unemployed,
            });
        });
    });

    return results;
}

function shadcnTooltipContent<TDatum>(points: readonly ChartPoint<TDatum>[]) {
    if (points.length === 0) return { title: "", rows: [] };
    const d = points[0].datum as BumpDatum;
    if (!d || !d.date) return { title: "", rows: [] };
    const dateObj = d.date instanceof Date ? d.date : new Date(d.date);
    const yearStr = isNaN(dateObj.getTime()) ? "" : ` (${dateObj.getUTCFullYear()})`;
    return {
        title: `${d.industry}${yearStr}`,
        rows: [
            { label: "Rank", value: `#${d.rank}`, color: "var(--chart-1)" },
            { label: "Unemployed Count", value: `${d.unemployed}k`, color: "var(--foreground)" },
        ],
    };
}

export function BumpRanking() {
    const rawData = useMemo(() => generateDemoData(), []);

    const rows = useMemo(() => {
        return rank(rawData, {
            by: "date",
            value: "unemployed",
            order: "descending",
        });
    }, [rawData]);

    const labels = useMemo(() => {
        return select(rows, {
            by: "industry",
            value: (datum: BumpDatum) =>
                datum?.date ? (datum.date instanceof Date ? datum.date.getTime() : new Date(datum.date).getTime()) : 0,
            select: "max",
        });
    }, [rows]);

    const definition = useMemo(
        () =>
            defineChart(
                {
                    renderer: motionRenderer,
                    marks: [
                        lineY(rows, {
                            id: "industry-ranks",
                            x: "date",
                            y: "rank",
                            color: "industry",
                            curve: d3Curve(curveBumpX),
                            strokeWidth: 2.5,
                        }),
                        dot(rows, {
                            id: "industry-rank-points",
                            x: "date",
                            y: "rank",
                            color: "industry",
                            r: 4,
                        }),
                        text(labels, {
                            id: "industry-labels",
                            x: "date",
                            y: "rank",
                            text: "industry",
                            color: "industry",
                            anchor: "start",
                            dx: 8,
                            fontSize: 10,
                            fontWeight: 600,
                        }),
                    ],
                    scales: {
                        x: {
                            scale: scaleUtc,
                            axis: {
                                ticks: {
                                    count: 6,
                                    format: (d: any) => {
                                        const date = d instanceof Date ? d : new Date(d);
                                        return isNaN(date.getTime()) ? "" : `${date.getUTCFullYear()}`;
                                    },
                                },
                                label: "Year",
                            },
                        },
                        y: {
                            scale: scaleLinear().domain([5.5, 0.5]),
                            grid: true,
                            axis: {
                                ticks: { count: 5, format: (v: number) => `#${v}` },
                                label: "Ranking Position",
                            },
                        },
                    },
                    color: {
                        domain: industriesList,
                        range: [
                            "var(--chart-1)",
                            "var(--chart-2)",
                            "var(--chart-3)",
                            "var(--chart-4)",
                            "var(--chart-5)",
                        ],
                    },
                    margin: { top: 24, right: 80, bottom: 32, left: 45 },
                    theme: {
                        foreground: "var(--muted-foreground)",
                        grid: "var(--border)",
                        background: "transparent",
                    },
                },
                {
                    keyboard: true,
                    tooltip: {
                        use: tooltip,
                        className:
                            "font-sans shadow-none rounded-md bg-popover text-popover-foreground border p-2 text-xs",
                        anchor: "pointer",
                        placement: "auto",
                        content: (points) => shadcnTooltipContent(points),
                    },
                },
            ),
        [rows, labels],
    );

    return (
        <Card className="w-full max-w-xl">
            <CardHeader>
                <CardTitle>Industry Unemployment Bump Chart</CardTitle>
                <CardDescription>
                    Curve-bump ranking lines tracking position shifts across annual observations
                </CardDescription>
            </CardHeader>
            <CardContent>
                <div className="h-[250px] w-full">
                    <Chart
                        definition={definition}
                        renderer={motionRenderer}
                        height={250}
                        ariaLabel="Industry Unemployment Bump Chart"
                    />
                </div>
            </CardContent>
            <CardFooter className="flex-col items-start gap-2 text-sm">
                <div className="flex items-center gap-2 leading-none font-medium">
                    Trade maintains top rank across recent observation years{" "}
                    <Trophy className="h-4 w-4 text-emerald-500" />
                </div>
                <div className="text-muted-foreground leading-none">
                    Smooth bump curves illustrate ordinal rank swaps over time
                </div>
            </CardFooter>
        </Card>
    );
}

export default BumpRanking;