import React, { useState } from "react";
import ReactMarkdown from "react-markdown";
import remarkGfm from "remark-gfm";
import remarkBreaks from "remark-breaks";
import rehypeRaw from "rehype-raw";
import rehypeSanitize, { defaultSchema } from "rehype-sanitize";
import { Prism as SyntaxHighlighter } from "react-syntax-highlighter";
import { Copy, Check } from "lucide-react";
import { useTheme } from "../context/ThemeContext";

// Sanitize schema that allows collapsible sections (details/summary)
const sanitizeSchema = {
  ...defaultSchema,
  tagNames: [...(defaultSchema.tagNames || []), "details", "summary"],
  attributes: {
    ...defaultSchema.attributes,
    details: ["open"], // Allow the 'open' attribute for expanded by default
  },
};

// Copy button component for code blocks
function CodeCopyButton({ code }: { code: string }) {
  const [copied, setCopied] = useState(false);

  const handleCopy = async () => {
    await navigator.clipboard.writeText(code);
    setCopied(true);
    setTimeout(() => setCopied(false), 2000);
  };

  return (
    <button
      className="code-copy-button"
      onClick={handleCopy}
      aria-label={copied ? "Copied!" : "Copy code"}
      title={copied ? "Copied!" : "Copy code"}
    >
      {copied ? <Check size={14} /> : <Copy size={14} />}
    </button>
  );
}

// Cursor Dark Theme colors for syntax highlighting
const cursorDarkTheme: { [key: string]: React.CSSProperties } = {
  'code[class*="language-"]': {
    color: "#d4d4d4",
    background: "#1e1e1e",
    fontFamily:
      "SF Mono, Monaco, Cascadia Code, Roboto Mono, Consolas, Courier New, monospace",
    fontSize: "14px",
    textAlign: "left" as const,
    whiteSpace: "pre" as const,
    wordSpacing: "normal",
    wordBreak: "normal" as const,
    wordWrap: "normal" as const,
    lineHeight: "1.6",
    tabSize: 4,
    hyphens: "none" as const,
  },
  'pre[class*="language-"]': {
    color: "#d4d4d4",
    background: "#1e1e1e",
    fontFamily:
      "SF Mono, Monaco, Cascadia Code, Roboto Mono, Consolas, Courier New, monospace",
    fontSize: "14px",
    textAlign: "left" as const,
    whiteSpace: "pre" as const,
    wordSpacing: "normal",
    wordBreak: "normal" as const,
    wordWrap: "normal" as const,
    lineHeight: "1.6",
    tabSize: 4,
    hyphens: "none" as const,
    padding: "1.5em",
    margin: "1.5em 0",
    overflow: "auto" as const,
    borderRadius: "8px",
  },
  comment: { color: "#6a9955", fontStyle: "italic" },
  prolog: { color: "#6a9955" },
  doctype: { color: "#6a9955" },
  cdata: { color: "#6a9955" },
  punctuation: { color: "#d4d4d4" },
  property: { color: "#9cdcfe" },
  tag: { color: "#569cd6" },
  boolean: { color: "#569cd6" },
  number: { color: "#b5cea8" },
  constant: { color: "#4fc1ff" },
  symbol: { color: "#4fc1ff" },
  deleted: { color: "#f44747" },
  selector: { color: "#d7ba7d" },
  "attr-name": { color: "#92c5f6" },
  string: { color: "#ce9178" },
  char: { color: "#ce9178" },
  builtin: { color: "#569cd6" },
  inserted: { color: "#6a9955" },
  operator: { color: "#d4d4d4" },
  entity: { color: "#dcdcaa" },
  url: { color: "#9cdcfe", textDecoration: "underline" },
  variable: { color: "#9cdcfe" },
  atrule: { color: "#569cd6" },
  "attr-value": { color: "#ce9178" },
  function: { color: "#dcdcaa" },
  "function-variable": { color: "#dcdcaa" },
  keyword: { color: "#569cd6" },
  regex: { color: "#d16969" },
  important: { color: "#569cd6", fontWeight: "bold" },
  bold: { fontWeight: "bold" },
  italic: { fontStyle: "italic" },
  namespace: { opacity: 0.7 },
  "class-name": { color: "#4ec9b0" },
  parameter: { color: "#9cdcfe" },
  decorator: { color: "#dcdcaa" },
};

// Cursor Light Theme colors for syntax highlighting
const cursorLightTheme: { [key: string]: React.CSSProperties } = {
  'code[class*="language-"]': {
    color: "#171717",
    background: "#f5f5f5",
    fontFamily:
      "SF Mono, Monaco, Cascadia Code, Roboto Mono, Consolas, Courier New, monospace",
    fontSize: "14px",
    textAlign: "left" as const,
    whiteSpace: "pre" as const,
    wordSpacing: "normal",
    wordBreak: "normal" as const,
    wordWrap: "normal" as const,
    lineHeight: "1.6",
    tabSize: 4,
    hyphens: "none" as const,
  },
  'pre[class*="language-"]': {
    color: "#171717",
    background: "#f5f5f5",
    fontFamily:
      "SF Mono, Monaco, Cascadia Code, Roboto Mono, Consolas, Courier New, monospace",
    fontSize: "14px",
    textAlign: "left" as const,
    whiteSpace: "pre" as const,
    wordSpacing: "normal",
    wordBreak: "normal" as const,
    wordWrap: "normal" as const,
    lineHeight: "1.6",
    tabSize: 4,
    hyphens: "none" as const,
    padding: "1.5em",
    margin: "1.5em 0",
    overflow: "auto" as const,
    borderRadius: "8px",
  },
  comment: { color: "#6a737d", fontStyle: "italic" },
  prolog: { color: "#6a737d" },
  doctype: { color: "#6a737d" },
  cdata: { color: "#6a737d" },
  punctuation: { color: "#24292e" },
  property: { color: "#005cc5" },
  tag: { color: "#22863a" },
  boolean: { color: "#005cc5" },
  number: { color: "#005cc5" },
  constant: { color: "#005cc5" },
  symbol: { color: "#e36209" },
  deleted: { color: "#b31d28", background: "#ffeef0" },
  selector: { color: "#22863a" },
  "attr-name": { color: "#6f42c1" },
  string: { color: "#032f62" },
  char: { color: "#032f62" },
  builtin: { color: "#005cc5" },
  inserted: { color: "#22863a", background: "#f0fff4" },
  operator: { color: "#d73a49" },
  entity: { color: "#6f42c1" },
  url: { color: "#005cc5", textDecoration: "underline" },
  variable: { color: "#e36209" },
  atrule: { color: "#005cc5" },
  "attr-value": { color: "#032f62" },
  function: { color: "#6f42c1" },
  "function-variable": { color: "#6f42c1" },
  keyword: { color: "#d73a49" },
  regex: { color: "#032f62" },
  important: { color: "#d73a49", fontWeight: "bold" },
  bold: { fontWeight: "bold" },
  italic: { fontStyle: "italic" },
  namespace: { opacity: 0.7 },
  "class-name": { color: "#6f42c1" },
  parameter: { color: "#24292e" },
  decorator: { color: "#6f42c1" },
};

// Tan Theme colors for syntax highlighting
const cursorTanTheme: { [key: string]: React.CSSProperties } = {
  'code[class*="language-"]': {
    color: "#1a1a1a",
    background: "#f0ece4",
    fontFamily:
      "SF Mono, Monaco, Cascadia Code, Roboto Mono, Consolas, Courier New, monospace",
    fontSize: "14px",
    textAlign: "left" as const,
    whiteSpace: "pre" as const,
    wordSpacing: "normal",
    wordBreak: "normal" as const,
    wordWrap: "normal" as const,
    lineHeight: "1.6",
    tabSize: 4,
    hyphens: "none" as const,
  },
  'pre[class*="language-"]': {
    color: "#1a1a1a",
    background: "#f0ece4",
    fontFamily:
      "SF Mono, Monaco, Cascadia Code, Roboto Mono, Consolas, Courier New, monospace",
    fontSize: "14px",
    textAlign: "left" as const,
    whiteSpace: "pre" as const,
    wordSpacing: "normal",
    wordBreak: "normal" as const,
    wordWrap: "normal" as const,
    lineHeight: "1.6",
    tabSize: 4,
    hyphens: "none" as const,
    padding: "1.5em",
    margin: "1.5em 0",
    overflow: "auto" as const,
    borderRadius: "8px",
  },
  comment: { color: "#7a7a7a", fontStyle: "italic" },
  prolog: { color: "#7a7a7a" },
  doctype: { color: "#7a7a7a" },
  cdata: { color: "#7a7a7a" },
  punctuation: { color: "#1a1a1a" },
  property: { color: "#8b7355" },
  tag: { color: "#8b5a2b" },
  boolean: { color: "#8b5a2b" },
  number: { color: "#8b5a2b" },
  constant: { color: "#8b5a2b" },
  symbol: { color: "#a67c52" },
  deleted: { color: "#b31d28" },
  selector: { color: "#6b8e23" },
  "attr-name": { color: "#8b7355" },
  string: { color: "#6b8e23" },
  char: { color: "#6b8e23" },
  builtin: { color: "#8b5a2b" },
  inserted: { color: "#6b8e23" },
  operator: { color: "#a67c52" },
  entity: { color: "#8b7355" },
  url: { color: "#8b7355", textDecoration: "underline" },
  variable: { color: "#a67c52" },
  atrule: { color: "#8b5a2b" },
  "attr-value": { color: "#6b8e23" },
  function: { color: "#8b7355" },
  "function-variable": { color: "#8b7355" },
  keyword: { color: "#8b5a2b" },
  regex: { color: "#6b8e23" },
  important: { color: "#8b5a2b", fontWeight: "bold" },
  bold: { fontWeight: "bold" },
  italic: { fontStyle: "italic" },
  namespace: { opacity: 0.7 },
  "class-name": { color: "#8b7355" },
  parameter: { color: "#1a1a1a" },
  decorator: { color: "#8b7355" },
};

interface BlogPostProps {
  content: string;
}

// Generate slug from heading text for anchor links
function generateSlug(text: string): string {
  return text
    .toLowerCase()
    .replace(/[^a-z0-9\s-]/g, "")
    .replace(/\s+/g, "-")
    .replace(/-+/g, "-")
    .trim();
}

// Extract text content from React children
function getTextContent(children: React.ReactNode): string {
  if (typeof children === "string") return children;
  if (Array.isArray(children)) {
    return children.map(getTextContent).join("");
  }
  if (children && typeof children === "object" && "props" in children) {
    return getTextContent((children as React.ReactElement).props.children);
  }
  return "";
}

export default function BlogPost({ content }: BlogPostProps) {
  const { theme } = useTheme();

  const getCodeTheme = () => {
    switch (theme) {
      case "dark":
        return cursorDarkTheme;
      case "light":
        return cursorLightTheme;
      case "tan":
        return cursorTanTheme;
      default:
        return cursorDarkTheme;
    }
  };

  return (
    <article className="blog-post-content">
      <ReactMarkdown
        remarkPlugins={[remarkGfm, remarkBreaks]}
        rehypePlugins={[rehypeRaw, [rehypeSanitize, sanitizeSchema]]}
        components={{
          code({ className, children, ...props }) {
            const match = /language-(\w+)/.exec(className || "");
            const isInline = !match && !className;

            if (isInline) {
              return (
                <code className="inline-code" {...props}>
                  {children}
                </code>
              );
            }

            const codeString = String(children).replace(/\n$/, "");
            return (
              <div className="code-block-wrapper">
                {match && <span className="code-language">{match[1]}</span>}
                <CodeCopyButton code={codeString} />
                <SyntaxHighlighter
                  style={getCodeTheme()}
                  language={match ? match[1] : "text"}
                  PreTag="div"
                >
                  {codeString}
                </SyntaxHighlighter>
              </div>
            );
          },
          img({ src, alt }) {
            return (
              <span className="blog-image-wrapper">
                <img
                  src={src}
                  alt={alt || ""}
                  className="blog-image"
                  loading="lazy"
                />
                {alt && <span className="blog-image-caption">{alt}</span>}
              </span>
            );
          },
          a({ href, children }) {
            const isExternal = href?.startsWith("http");
            return (
              <a
                href={href}
                target={isExternal ? "_blank" : undefined}
                rel={isExternal ? "noopener noreferrer" : undefined}
                className="blog-link"
              >
                {children}
              </a>
            );
          },
          blockquote({ children }) {
            return (
              <blockquote className="blog-blockquote">{children}</blockquote>
            );
          },
          h1({ children }) {
            const id = generateSlug(getTextContent(children));
            return (
              <h1 id={id} className="blog-h1">
                {children}
              </h1>
            );
          },
          h2({ children }) {
            const id = generateSlug(getTextContent(children));
            return (
              <h2 id={id} className="blog-h2">
                {children}
              </h2>
            );
          },
          h3({ children }) {
            const id = generateSlug(getTextContent(children));
            return (
              <h3 id={id} className="blog-h3">
                {children}
              </h3>
            );
          },
          h4({ children }) {
            const id = generateSlug(getTextContent(children));
            return (
              <h4 id={id} className="blog-h4">
                {children}
              </h4>
            );
          },
          h5({ children }) {
            const id = generateSlug(getTextContent(children));
            return (
              <h5 id={id} className="blog-h5">
                {children}
              </h5>
            );
          },
          h6({ children }) {
            const id = generateSlug(getTextContent(children));
            return (
              <h6 id={id} className="blog-h6">
                {children}
              </h6>
            );
          },
          ul({ children }) {
            return <ul className="blog-ul">{children}</ul>;
          },
          ol({ children }) {
            return <ol className="blog-ol">{children}</ol>;
          },
          li({ children }) {
            return <li className="blog-li">{children}</li>;
          },
          hr() {
            return <hr className="blog-hr" />;
          },
          // Table components for GitHub-style tables
          table({ children }) {
            return (
              <div className="blog-table-wrapper">
                <table className="blog-table">{children}</table>
              </div>
            );
          },
          thead({ children }) {
            return <thead className="blog-thead">{children}</thead>;
          },
          tbody({ children }) {
            return <tbody className="blog-tbody">{children}</tbody>;
          },
          tr({ children }) {
            return <tr className="blog-tr">{children}</tr>;
          },
          th({ children }) {
            return <th className="blog-th">{children}</th>;
          },
          td({ children }) {
            return <td className="blog-td">{children}</td>;
          },
        }}
      >
        {content}
      </ReactMarkdown>
    </article>
  );
}