import * as React from "react";
import * as RechartsPrimitive from "recharts";
import type { TooltipValueType } from "recharts";

import { cn } from "../lib/utils";

// Format: { THEME_NAME: CSS_SELECTOR }
const THEMES = { light: "", dark: ".dark" } as const;

const INITIAL_DIMENSION = { width: 320, height: 200 } as const;
type TooltipNameType = number | string;

export type ChartConfig = Record<
  string,
  {
    label?: React.ReactNode;
    icon?: React.ComponentType;
  } & (
    | { color?: string; theme?: never }
    | { color?: never; theme: Record<keyof typeof THEMES, string> }
  )
>;

type ChartContextProps = {
  config: ChartConfig;
};

const cssIdentifierPattern = /^[A-Za-z_][A-Za-z0-9_-]*$/;
const cssColorPattern =
  /^(?:#[0-9A-Fa-f]{3,8}|(?:rgb|hsl)a?\(\s*[-+0-9.%]+\s*(?:,\s*[-+0-9.%]+\s*){2}(?:,\s*[-+0-9.]+\s*)?\)|(?:rgb|hsl)a?\(\s*[-+0-9.%]+\s+[-+0-9.%]+\s+[-+0-9.%]+(?:\s*\/\s*[-+0-9.%]+)?\s*\)|[A-Za-z]+|var\(--[A-Za-z0-9_-]+\))$/;

export const chartCssVariableName = (key: string): string | null =>
  cssIdentifierPattern.test(key) ? `--color-${key}` : null;

export const chartCssColorValue = (color: string): string | null => {
  const trimmed = color.trim();
  return cssColorPattern.test(trimmed) ? trimmed : null;
};

const ChartContext = React.createContext<ChartContextProps | null>(null);

function useChart() {
  const context = React.useContext(ChartContext);

  if (!context) {
    throw new Error("useChart must be used within a <ChartContainer />");
  }

  return context;
}

function ChartContainer({
  id,
  className,
  children,
  config,
  initialDimension = INITIAL_DIMENSION,
  ...props
}: React.ComponentProps<"div"> & {
  config: ChartConfig;
  children: React.ComponentProps<typeof RechartsPrimitive.ResponsiveContainer>["children"];
  initialDimension?: {
    width: number;
    height: number;
  };
}) {
  const uniqueId = React.useId();
  const chartId = `chart-${id ?? uniqueId.replace(/:/g, "")}`;

  return (
    <ChartContext.Provider value={{ config }}>
      <div
        data-slot="chart"
        data-chart={chartId}
        className={cn(
          "flex aspect-video justify-center text-xs [&_.recharts-cartesian-axis-tick_text]:fill-muted-foreground [&_.recharts-cartesian-grid_line[stroke='#ccc']]:stroke-border/50 [&_.recharts-curve.recharts-tooltip-cursor]:stroke-border [&_.recharts-dot[stroke='#fff']]:stroke-transparent [&_.recharts-layer]:outline-hidden [&_.recharts-polar-grid_[stroke='#ccc']]:stroke-border [&_.recharts-radial-bar-background-sector]:fill-muted [&_.recharts-rectangle.recharts-tooltip-cursor]:fill-muted [&_.recharts-reference-line_[stroke='#ccc']]:stroke-border [&_.recharts-sector]:outline-hidden [&_.recharts-sector[stroke='#fff']]:stroke-transparent [&_.recharts-surface]:outline-hidden",
          className,
        )}
        {...props}
      >
        <ChartStyle id={chartId} config={config} />
        <RechartsPrimitive.ResponsiveContainer initialDimension={initialDimension}>
          {children}
        </RechartsPrimitive.ResponsiveContainer>
      </div>
    </ChartContext.Provider>
  );
}

const ChartStyle = ({ id, config }: { id: string; config: ChartConfig }) => {
  const colorConfig = Object.entries(config).filter(([, config]) => config.theme ?? config.color);

  if (!colorConfig.length) {
    return null;
  }

  return (
    <style
      dangerouslySetInnerHTML={{
        __html: Object.entries(THEMES)
          .map(
            ([theme, prefix]) => `
${prefix} [data-chart=${id}] {
${colorConfig
  .map(([key, itemConfig]) => {
    const color = itemConfig.theme?.[theme as keyof typeof itemConfig.theme] ?? itemConfig.color;
    const variableName = chartCssVariableName(key);
    const colorValue = color ? chartCssColorValue(color) : null;
    return variableName && colorValue ? `  ${variableName}: ${colorValue};` : null;
  })
  .filter((line): line is string => line !== null)
  .join("\n")}
}
`,
          )
          .join("\n"),
      }}
    />
  );
};

const ChartTooltip = RechartsPrimitive.Tooltip;

function ChartTooltipContent({
  active,
  payload,
  className,
  indicator = "dot",
  hideLabel = false,
  hideIndicator = false,
  label,
  labelFormatter,
  labelClassName,
  formatter,
  color,
  nameKey,
  labelKey,
}: React.ComponentProps<typeof RechartsPrimitive.Tooltip> &
  React.ComponentProps<"div"> & {
    hideLabel?: boolean;
    hideIndicator?: boolean;
    indicator?: "line" | "dot" | "dashed";
    nameKey?: string;
    labelKey?: string;
  } & Omit<
    RechartsPrimitive.DefaultTooltipContentProps<TooltipValueType, TooltipNameType>,
    "accessibilityLayer"
  >) {
  const { config } = useChart();

  const tooltipLabel = React.useMemo(() => {
    if (hideLabel || !payload?.length) {
      return null;
    }

    const [item] = payload;
    const key = `${labelKey ?? item?.dataKey ?? item?.name ?? "value"}`;
    const itemConfig = getPayloadConfigFromPayload(config, item, key);
    const value =
      !labelKey && typeof label === "string" ? (config[label]?.label ?? label) : itemConfig?.label;

    if (labelFormatter) {
      return (
        <div className={cn("font-medium", labelClassName)}>{labelFormatter(value, payload)}</div>
      );
    }

    if (!value) {
      return null;
    }

    return <div className={cn("font-medium", labelClassName)}>{value}</div>;
  }, [label, labelFormatter, payload, hideLabel, labelClassName, config, labelKey]);

  if (!active || !payload?.length) {
    return null;
  }

  const nestLabel = payload.length === 1 && indicator !== "dot";

  return (
    <div
      className={cn(
        "grid min-w-[8rem] items-start gap-1.5 rounded-lg border border-border/50 bg-background px-2.5 py-1.5 text-xs shadow-xl",
        className,
      )}
    >
      {!nestLabel ? tooltipLabel : null}
      <div className="grid gap-1.5">
        {payload
          .filter((item) => item.type !== "none")
          .map((item, index) => {
            const key = `${nameKey ?? item.name ?? item.dataKey ?? "value"}`;
            const itemConfig = getPayloadConfigFromPayload(config, item, key);
            const indicatorColor = color ?? item.payload?.fill ?? item.color;

            return (
              <div
                key={index}
                className={cn(
                  "flex w-full flex-wrap items-stretch gap-2 [&>svg]:h-2.5 [&>svg]:w-2.5 [&>svg]:text-muted-foreground",
                  indicator === "dot" && "items-center",
                )}
              >
                {formatter && item?.value !== undefined && item.name ? (
                  formatter(item.value, item.name, item, index, item.payload)
                ) : (
                  <>
                    {itemConfig?.icon ? (
                      <itemConfig.icon />
                    ) : (
                      !hideIndicator && (
                        <div
                          className={cn(
                            "shrink-0 rounded-[2px] border-(--color-border) bg-(--color-bg)",
                            {
                              "h-2.5 w-2.5": indicator === "dot",
                              "w-1": indicator === "line",
                              "w-0 border-[1.5px] border-dashed bg-transparent":
                                indicator === "dashed",
                              "my-0.5": nestLabel && indicator === "dashed",
                            },
                          )}
                          style={
                            {
                              "--color-bg": indicatorColor,
                              "--color-border": indicatorColor,
                            } as React.CSSProperties
                          }
                        />
                      )
                    )}
                    <div
                      className={cn(
                        "flex flex-1 justify-between leading-none",
                        nestLabel ? "items-end" : "items-center",
                      )}
                    >
                      <div className="grid gap-1.5">
                        {nestLabel ? tooltipLabel : null}
                        <span className="text-muted-foreground">
                          {itemConfig?.label ?? item.name}
                        </span>
                      </div>
                      {item.value != null && (
                        <span className="font-mono font-medium text-foreground tabular-nums">
                          {typeof item.value === "number"
                            ? item.value.toLocaleString()
                            : String(item.value)}
                        </span>
                      )}
                    </div>
                  </>
                )}
              </div>
            );
          })}
      </div>
    </div>
  );
}

const ChartLegend = RechartsPrimitive.Legend;

function ChartLegendContent({
  className,
  hideIcon = false,
  payload,
  verticalAlign = "bottom",
  nameKey,
}: React.ComponentProps<"div"> & {
  hideIcon?: boolean;
  nameKey?: string;
} & RechartsPrimitive.DefaultLegendContentProps) {
  const { config } = useChart();

  if (!payload?.length) {
    return null;
  }

  return (
    <div
      className={cn(
        "flex items-center justify-center gap-4",
        verticalAlign === "top" ? "pb-3" : "pt-3",
        className,
      )}
    >
      {payload
        .filter((item) => item.type !== "none")
        .map((item, index) => {
          const key = `${nameKey ?? item.dataKey ?? "value"}`;
          const itemConfig = getPayloadConfigFromPayload(config, item, key);

          return (
            <div
              key={index}
              className={cn(
                "flex items-center gap-1.5 [&>svg]:h-3 [&>svg]:w-3 [&>svg]:text-muted-foreground",
              )}
            >
              {itemConfig?.icon && !hideIcon ? (
                <itemConfig.icon />
              ) : (
                <div
                  className="h-2 w-2 shrink-0 rounded-[2px]"
                  style={{
                    backgroundColor: item.color,
                  }}
                />
              )}
              {itemConfig?.label}
            </div>
          );
        })}
    </div>
  );
}

// Helper to extract item config from a payload.
const isRecord = (value: unknown): value is Record<string, unknown> =>
  typeof value === "object" && value !== null && !Array.isArray(value);

function getPayloadConfigFromPayload(config: ChartConfig, payload: unknown, key: string) {
  if (!isRecord(payload)) {
    return undefined;
  }

  const payloadPayload = isRecord(payload.payload) ? payload.payload : undefined;

  let configLabelKey: string = key;

  if (typeof payload[key] === "string") {
    configLabelKey = payload[key];
  } else if (payloadPayload && typeof payloadPayload[key] === "string") {
    configLabelKey = payloadPayload[key];
  }

  return configLabelKey in config ? config[configLabelKey] : config[key];
}

export {
  ChartContainer,
  ChartTooltip,
  ChartTooltipContent,
  ChartLegend,
  ChartLegendContent,
  ChartStyle,
};