import React, { useMemo } from "react";
import { Linking, type StyleProp, Text, type TextStyle } from "react-native";
import { cn, useThemeColor } from "heroui-native";

export interface NLinkifyProps {
  children: React.ReactNode;
  className?: string;
  numberOfLines?: number;
  linkStyle?: StyleProp<TextStyle>;
  onPress?: (url: string, text: string) => void;
}

const URL_REGEX =
  /(?:https?:\/\/|www\.)[^\s<>'"]+|[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}/gi;

function parseText(text: string): { type: "text" | "url" | "email"; value: string }[] {
  const parts: { type: "text" | "url" | "email"; value: string }[] = [];
  let lastIndex = 0;
  let match: RegExpExecArray | null;

  URL_REGEX.lastIndex = 0;
  while ((match = URL_REGEX.exec(text)) !== null) {
    if (match.index > lastIndex) {
      parts.push({ type: "text", value: text.slice(lastIndex, match.index) });
    }
    const value = match[0];
    const isEmail = value.includes("@") && !value.includes("://");
    parts.push({ type: isEmail ? "email" : "url", value });
    lastIndex = URL_REGEX.lastIndex;
  }

  if (lastIndex < text.length) {
    parts.push({ type: "text", value: text.slice(lastIndex) });
  }

  return parts;
}

function getHref(part: { type: "text" | "url" | "email"; value: string }): string {
  if (part.type === "email") return `mailto:${part.value}`;
  if (part.value.startsWith("http")) return part.value;
  return `https://${part.value}`;
}

export const NLinkify = React.memo<NLinkifyProps>(
  ({ children, className, numberOfLines, linkStyle, onPress }) => {
    const [accentColor] = useThemeColor(["accent"]);

    const defaultLinkStyle = useMemo<TextStyle>(
      () => ({ color: accentColor, textDecorationLine: "underline" as const }),
      [accentColor],
    );

    const handlePress = (href: string, text: string) => {
      if (onPress) {
        onPress(href, text);
      } else {
        Linking.openURL(href).catch(() => {});
      }
    };

    const renderNode = (node: React.ReactNode, key?: string): React.ReactNode => {
      if (typeof node === "string") {
        const parts = parseText(node);
        if (parts.length === 1 && parts[0]!.type === "text") return node;

        return parts.map((part, i) => {
          if (part.type === "text") return part.value;
          const href = getHref(part);
          return (
            <Text
              key={`${key || "link"}-${i}`}
              style={[defaultLinkStyle, linkStyle]}
              onPress={() => handlePress(href, part.value)}
            >
              {part.value}
            </Text>
          );
        });
      }

      if (React.isValidElement(node)) {
        const element = node as React.ReactElement<any>;
        const nodeChildren = element.props?.children;
        if (nodeChildren == null) return node;

        const processedChildren = Array.isArray(nodeChildren)
          ? nodeChildren.map((child, i) => renderNode(child, `${key || "c"}-${i}`))
          : renderNode(nodeChildren, key);

        return React.cloneElement(element, { key: key || element.key }, processedChildren);
      }

      return node;
    };

    const rendered = Array.isArray(children)
      ? children.map((child, i) => renderNode(child, `root-${i}`))
      : renderNode(children, "root");

    return (
      <Text className={cn(className)} numberOfLines={numberOfLines}>
        {rendered}
      </Text>
    );
  },
);

NLinkify.displayName = "NLinkify";