import React, { useState, useRef } from 'react';
import ReactMarkdown from 'react-markdown';
import remarkGfm from 'remark-gfm';
import { Icons } from './IconSet';

interface MarkdownEditorProps {
  value: string;
  onChange: (value: string) => void;
  className?: string;
}

const MarkdownEditor: React.FC<MarkdownEditorProps> = ({ value, onChange, className = '' }) => {
  const textareaRef = useRef<HTMLTextAreaElement>(null);

  const insertText = (before: string, after: string = '', placeholder: string = 'text') => {
    const textarea = textareaRef.current;
    if (!textarea) return;

    const start = textarea.selectionStart;
    const end = textarea.selectionEnd;
    const selectedText = value.substring(start, end);
    const textToInsert = selectedText || placeholder;

    const newText = value.substring(0, start) + before + textToInsert + after + value.substring(end);
    onChange(newText);

    // Set cursor position after the inserted text
    setTimeout(() => {
      const newCursorPos = start + before.length + textToInsert.length + after.length;
      textarea.setSelectionRange(newCursorPos, newCursorPos);
      textarea.focus();
    }, 0);
  };

  const formatButtons = [
    {
      icon: 'H',
      label: 'Überschrift',
      action: () => insertText('# ', ''),
      className: 'text-lg font-bold'
    },
    {
      icon: <Icons.Hammer className="w-3 h-3" />,
      label: 'Fett',
      action: () => insertText('**', '**', 'fetter Text'),
    },
    {
      icon: <Icons.Tag className="w-3 h-3" />,
      label: 'Kursiv',
      action: () => insertText('*', '*', 'kursiver Text'),
    },
    {
      icon: <Icons.Scroll className="w-3 h-3" />,
      label: 'Liste',
      action: () => insertText('- ', ''),
    },
    {
      icon: <Icons.Crown className="w-3 h-3" />,
      label: 'Nummerierte Liste',
      action: () => insertText('1. ', ''),
    },
    {
      icon: <Icons.Shield className="w-3 h-3" />,
      label: 'Zitat',
      action: () => insertText('> ', ''),
    },
    {
      icon: '🔗',
      label: 'Link',
      action: () => insertText('[', '](url)', 'Link-Text'),
    },
    {
      icon: '📷',
      label: 'Bild',
      action: () => insertText('![', '](url)', 'Alt-Text'),
    },
  ];

  return (
    <div className={`border border-border rounded-lg overflow-hidden ${className}`}>
      {/* Toolbar */}
      <div className="bg-surfaceHighlight border-b border-border p-2 flex flex-wrap gap-1">
        {formatButtons.map((button, index) => (
          <button
            key={index}
            type="button"
            onClick={button.action}
            className="p-1.5 hover:bg-white/10 rounded text-textMuted hover:text-textMain transition-colors text-sm flex items-center justify-center min-w-[32px] h-8"
            title={button.label}
          >
            {typeof button.icon === 'string' ? (
              <span className={button.className}>{button.icon}</span>
            ) : (
              button.icon
            )}
          </button>
        ))}
      </div>

      {/* Editor and Preview */}
      <div className="flex h-64 md:h-96">
        {/* Textarea */}
        <textarea
          ref={textareaRef}
          value={value}
          onChange={(e) => onChange(e.target.value)}
          className="w-1/2 h-full bg-[#0b0b0d] border-0 border-r border-border p-4 text-sm font-mono text-gray-300 focus:outline-none resize-none"
          placeholder="Schreibe dein Journal hier... Verwende die Toolbar für Formatierung."
          spellCheck={false}
        />
        {/* Preview */}
        <div className="w-1/2 h-full bg-[#0b0b0d] p-4 text-sm text-gray-300 overflow-auto">
          <ReactMarkdown remarkPlugins={[remarkGfm]}>
            {value || 'Hier erscheint die Vorschau deiner Markdown-Formatierung.'}
          </ReactMarkdown>
        </div>
      </div>

      {/* Footer */}
      <div className="bg-surfaceHighlight border-t border-border px-4 py-2 text-xs text-textMuted">
        Markdown-Formatierung unterstützt. Verwende die Toolbar für schnelle Formatierung.
      </div>
    </div>
  );
};

export default MarkdownEditor;