"use client";

import { RefObject } from "react";
import { Heading2, Heading3, Code, Quote, Image, Link, Minus, Bold, FileCode } from "lucide-react";

interface ShortcutPanelProps {
  textareaRef: RefObject<HTMLTextAreaElement | null>;
  value: string;
  onChange: (value: string) => void;
}

export default function ShortcutPanel({ textareaRef, value, onChange }: ShortcutPanelProps) {
  const insert = (before: string, after: string, placeholder: string) => {
    const el = textareaRef.current;
    if (!el) {
      onChange(value + before + placeholder + after);
      return;
    }
    const start = el.selectionStart;
    const end = el.selectionEnd;
    const selected = value.slice(start, end) || placeholder;
    const newVal = value.slice(0, start) + before + selected + after + value.slice(end);
    onChange(newVal);
    setTimeout(() => {
      const pos = start + before.length + selected.length + after.length;
      el.setSelectionRange(start + before.length, pos);
      el.focus();
    }, 0);
  };

  const shortcuts = [
    { label: "H2", icon: Heading2, action: () => insert("## ", "\n", "二级标题") },
    { label: "H3", icon: Heading3, action: () => insert("### ", "\n", "三级标题") },
    { label: "粗体", icon: Bold, action: () => insert("**", "**", "粗体文本") },
    { label: "代码块", icon: FileCode, action: () => insert("```\n", "\n```\n", "代码") },
    { label: "行内代码", icon: Code, action: () => insert("`", "`", "code") },
    { label: "引用", icon: Quote, action: () => insert("> ", "\n", "引用内容") },
    { label: "图片", icon: Image, action: () => insert("![", "]()", "描述") },
    { label: "链接", icon: Link, action: () => insert("[", "]()", "链接文本") },
    { label: "分割线", icon: Minus, action: () => insert("\n---\n", "", "") },
  ];

  return (
    <div>
      <h3 className="text-[11px] font-medium text-muted uppercase tracking-wider mb-3">快捷插入</h3>
      <div className="bg-card border border-line rounded-lg p-3 space-y-1">
        {shortcuts.map((s) => (
          <button
            key={s.label}
            type="button"
            onClick={s.action}
            className="w-full flex items-center gap-2.5 px-2.5 py-2 text-[12px] text-text/70 hover:text-accent hover:bg-accent/4 rounded transition-colors"
            title={s.label}
          >
            <s.icon size={14} className="shrink-0" />
            <span>{s.label}</span>
          </button>
        ))}
      </div>
      <div className="mt-4 p-3 bg-surface border border-line/50 rounded-lg">
        <h4 className="text-[10px] font-medium text-muted uppercase tracking-wider mb-2">说明</h4>
        <ul className="text-[11px] text-muted/70 space-y-1 leading-relaxed">
          <li>选中文字后点按钮可包裹</li>
          <li>未选中则插入模板 + 占位文字</li>
          <li>代码块自动补全语言标注</li>
        </ul>
      </div>
    </div>
  );
}