Candlestick Chart

import { type ChartPoint, defineChart, link } 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 { CandlestickChart as CandlestickIcon } from "lucide-react";

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

interface CandleDatum {
    Date: Date;
    Open: number;
    High: number;
    Low: number;
    Close: number;
}

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

function generateDemoData(): CandleDatum[] {
    const baseDate = new Date(2025, 0, 1);
    const results: CandleDatum[] = [];
    let prevClose = 220;

    for (let i = 0; i < 20; i++) {
        const d = new Date(baseDate);
        d.setDate(baseDate.getDate() + i);
        const open = prevClose + Math.sin(i * 0.7) * 4;
        const delta = Math.cos(i * 0.9) * 8 + (i % 2 === 0 ? 3 : -3);
        const close = open + delta;
        const high = Math.max(open, close) + Math.abs(Math.sin(i)) * 5;
        const low = Math.min(open, close) - Math.abs(Math.cos(i)) * 5;
        prevClose = close;
        results.push({ Date: d, Open: open, High: high, Low: low, Close: close });
    }
    return results;
}

function shadcnTooltipContent<TDatum>(points: readonly ChartPoint<TDatum>[]) {
    if (points.length === 0) return { title: "", rows: [] };
    const d = points[0].datum as CandleDatum;
    if (!d || !d.Date) return { title: "", rows: [] };
    const dateObj = d.Date instanceof Date ? d.Date : new Date(d.Date);
    const dateStr = isNaN(dateObj.getTime())
        ? ""
        : dateObj.toLocaleDateString("en-US", { month: "short", day: "numeric" });
    const isGain = d.Close >= d.Open;
    return {
        title: dateStr,
        rows: [
            { label: "Open", value: `$${d.Open.toFixed(2)}`, color: "var(--foreground)" },
            { label: "High", value: `$${d.High.toFixed(2)}`, color: "var(--foreground)" },
            { label: "Low", value: `$${d.Low.toFixed(2)}`, color: "var(--foreground)" },
            { label: "Close", value: `$${d.Close.toFixed(2)}`, color: isGain ? "var(--chart-1)" : "var(--chart-2)" },
        ],
    };
}

export function Candlestick() {
    const data = useMemo(() => generateDemoData(), []);

    const { gains, losses } = useMemo(() => {
        return {
            gains: data.filter((d) => d.Close >= d.Open),
            losses: data.filter((d) => d.Close < d.Open),
        };
    }, [data]);

    const definition = useMemo(
        () =>
            defineChart(
                {
                    renderer: motionRenderer,
                    marks: [
                        link(data, {
                            id: "candle-wicks",
                            x1: "Date",
                            y1: "Low",
                            x2: "Date",
                            y2: "High",
                            stroke: "var(--border)",
                            strokeWidth: 1.5,
                        }),
                        link(gains, {
                            id: "candle-gains",
                            x1: "Date",
                            y1: "Open",
                            x2: "Date",
                            y2: "Close",
                            stroke: "var(--chart-1)",
                            strokeWidth: 6,
                        }),
                        link(losses, {
                            id: "candle-losses",
                            x1: "Date",
                            y1: "Open",
                            x2: "Date",
                            y2: "Close",
                            stroke: "var(--chart-2)",
                            strokeWidth: 6,
                        }),
                    ],
                    scales: {
                        x: {
                            scale: scaleUtc,
                            axis: {
                                line: false,
                                label: "Date",
                                ticks: {
                                    size: 0,
                                    padding: 10,
                                    format: (d: any) => {
                                        const dateObj = d instanceof Date ? d : new Date(d);
                                        return isNaN(dateObj.getTime())
                                            ? ""
                                            : dateObj.toLocaleDateString("en-US", { month: "short", day: "numeric" });
                                    },
                                },
                            },
                        },
                        y: {
                            scale: scaleLinear().domain([190, 260]),
                            grid: true,
                            axis: {
                                line: false,
                                label: "Price ($)",
                                ticks: { size: 0 },
                            },
                        },
                    },
                    margin: { top: 24, right: 24, bottom: 32, left: 45 },
                    theme: {
                        foreground: "var(--muted-foreground)",
                        grid: "var(--border)",
                        background: "transparent",
                    },
                },
                {
                    focus: "group-x",
                    tooltip: {
                        use: tooltip,
                        className:
                            "font-sans shadow-none rounded-md bg-popover text-popover-foreground border p-2 text-xs",
                        anchor: "group-center",
                        placement: "auto",
                        content: (points) => shadcnTooltipContent(points),
                    },
                },
            ),
        [data, gains, losses],
    );

    return (
        <Card className="w-full max-w-xl">
            <CardHeader>
                <CardTitle>Daily Asset Candlesticks</CardTitle>
                <CardDescription>Daily Open-High-Low-Close price action candlesticks</CardDescription>
            </CardHeader>
            <CardContent>
                <div className="h-[250px] w-full">
                    <Chart
                        definition={definition}
                        renderer={motionRenderer}
                        height={250}
                        ariaLabel="Daily Asset Candlesticks Chart"
                    />
                </div>
            </CardContent>
            <CardFooter className="flex-col items-start gap-2 text-sm">
                <div className="flex items-center gap-2 leading-none font-medium">
                    Bullish candles (green) dominate recent 10 trading sessions{" "}
                    <CandlestickIcon className="h-4 w-4 text-emerald-500" />
                </div>
                <div className="text-muted-foreground leading-none">
                    Thin wicks indicate high/low range; thick bodies represent open/close spread
                </div>
            </CardFooter>
        </Card>
    );
}

export default Candlestick;