'use client';

import { useMemo, useState } from 'react';
import { motion } from 'framer-motion';
import ReactMarkdown from 'react-markdown';
import { User, Bot, Copy, Check, ExternalLink, ThumbsUp, ThumbsDown, Share2, Sparkles } from 'lucide-react';
import * as Tooltip from '@radix-ui/react-tooltip';
import type { Message, Citation as CitationType } from '@/lib/types';

interface ChatMessageProps {
  message: Message;
}

export function ChatMessage({ message }: ChatMessageProps) {
  const [copied, setCopied] = useState(false);
  const [feedback, setFeedback] = useState<'up' | 'down' | null>(null);
  const isUser = message.role === 'user';

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

  return (
    <motion.div
      initial={{ opacity: 0, y: 12 }}
      animate={{ opacity: 1, y: 0 }}
      transition={{ duration: 0.3, ease: 'easeOut' }}
      className={`group ${isUser ? 'flex justify-end' : ''}`}
    >
      {isUser ? (
        <div className="max-w-[85%] flex items-start gap-3 flex-row-reverse">
          <div className="w-9 h-9 rounded-xl bg-accent/10 border border-accent/20 flex items-center justify-center flex-shrink-0">
            <User className="w-4 h-4 text-accent" />
          </div>
          <div className="bg-surface/60 border border-border/50 rounded-2xl rounded-tr-sm px-4 py-3">
            <p className="text-[15px] text-primary leading-relaxed">{message.content}</p>
          </div>
        </div>
      ) : (
        <div className="max-w-full">
          {/* Assistant Header */}
          <div className="flex items-center gap-2.5 mb-4">
            <div className="w-9 h-9 rounded-xl bg-accent/10 border border-accent/20 flex items-center justify-center">
              <Sparkles className="w-4 h-4 text-accent" />
            </div>
            <span className="text-sm font-medium text-secondary">GooSeek</span>
          </div>

          {/* Citations - Show at top like Perplexity */}
          {message.citations && message.citations.length > 0 && (
            <div className="mb-5">
              <div className="flex flex-wrap gap-2">
                {message.citations.slice(0, 6).map((citation) => (
                  <CitationBadge key={citation.index} citation={citation} />
                ))}
                {message.citations.length > 6 && (
                  <button className="text-xs text-muted hover:text-secondary px-2.5 py-1.5 rounded-lg hover:bg-surface/40 transition-colors">
                    +{message.citations.length - 6} ещё
                  </button>
                )}
              </div>
            </div>
          )}

          {/* Message Content */}
          <div className="prose prose-invert max-w-none">
            <ReactMarkdown
              components={{
                p: ({ children }) => (
                  <p className="mb-4 last:mb-0 text-[15px] text-primary/90 leading-[1.7]">
                    {children}
                  </p>
                ),
                a: ({ href, children }) => (
                  <a
                    href={href}
                    target="_blank"
                    rel="noopener noreferrer"
                    className="text-accent hover:text-accent-hover underline underline-offset-2 decoration-accent/30 hover:decoration-accent/50 transition-colors"
                  >
                    {children}
                  </a>
                ),
                code: ({ className, children }) => {
                  const isInline = !className;
                  if (isInline) {
                    return (
                      <code className="px-1.5 py-0.5 bg-surface/80 border border-border/50 rounded-md text-[13px] text-accent-secondary font-mono">
                        {children}
                      </code>
                    );
                  }
                  return <code className={className}>{children}</code>;
                },
                pre: ({ children }) => (
                  <pre className="bg-elevated/80 border border-border/50 p-4 rounded-xl overflow-x-auto text-[13px] my-5 font-mono">
                    {children}
                  </pre>
                ),
                ul: ({ children }) => (
                  <ul className="list-none pl-0 my-4 space-y-2.5">{children}</ul>
                ),
                ol: ({ children }) => (
                  <ol className="list-none pl-0 my-4 space-y-2.5 counter-reset-item">
                    {children}
                  </ol>
                ),
                li: ({ children }) => (
                  <li className="flex gap-3 text-[15px] text-primary/85">
                    <span className="text-accent/60 select-none mt-0.5">•</span>
                    <span className="leading-[1.6]">{children}</span>
                  </li>
                ),
                h1: ({ children }) => (
                  <h1 className="text-xl font-semibold text-primary mt-8 mb-4">
                    {children}
                  </h1>
                ),
                h2: ({ children }) => (
                  <h2 className="text-lg font-semibold text-primary mt-6 mb-3">
                    {children}
                  </h2>
                ),
                h3: ({ children }) => (
                  <h3 className="text-base font-medium text-primary mt-5 mb-2">
                    {children}
                  </h3>
                ),
                blockquote: ({ children }) => (
                  <blockquote className="border-l-2 border-accent/40 pl-4 my-5 text-secondary italic">
                    {children}
                  </blockquote>
                ),
                strong: ({ children }) => (
                  <strong className="font-semibold text-primary">{children}</strong>
                ),
              }}
            >
              {message.content}
            </ReactMarkdown>

            {/* Streaming Cursor */}
            {message.isStreaming && (
              <span className="inline-block w-2 h-5 bg-accent/60 rounded-sm animate-pulse-soft ml-1" />
            )}
          </div>

          {/* Actions */}
          {!message.isStreaming && (
            <div className="flex items-center gap-1 mt-5 opacity-0 group-hover:opacity-100 transition-opacity duration-200">
              <ActionButton
                icon={copied ? Check : Copy}
                label={copied ? 'Скопировано' : 'Копировать'}
                onClick={handleCopy}
                active={copied}
              />
              <ActionButton
                icon={Share2}
                label="Поделиться"
                onClick={() => {}}
              />
              <div className="w-px h-4 bg-border/50 mx-1.5" />
              <ActionButton
                icon={ThumbsUp}
                label="Полезно"
                onClick={() => setFeedback('up')}
                active={feedback === 'up'}
              />
              <ActionButton
                icon={ThumbsDown}
                label="Не полезно"
                onClick={() => setFeedback('down')}
                active={feedback === 'down'}
              />
            </div>
          )}
        </div>
      )}
    </motion.div>
  );
}

interface ActionButtonProps {
  icon: React.ElementType;
  label: string;
  onClick: () => void;
  active?: boolean;
}

function ActionButton({ icon: Icon, label, onClick, active }: ActionButtonProps) {
  return (
    <Tooltip.Provider>
      <Tooltip.Root>
        <Tooltip.Trigger asChild>
          <button
            onClick={onClick}
            className={`
              p-2 rounded-lg transition-all
              ${active
                ? 'text-accent bg-accent/10'
                : 'text-muted hover:text-secondary hover:bg-surface/50'
              }
            `}
          >
            <Icon className="w-4 h-4" />
          </button>
        </Tooltip.Trigger>
        <Tooltip.Portal>
          <Tooltip.Content
            side="top"
            className="px-2.5 py-1.5 text-xs text-primary bg-surface border border-border rounded-lg shadow-dropdown z-50"
            sideOffset={4}
          >
            {label}
          </Tooltip.Content>
        </Tooltip.Portal>
      </Tooltip.Root>
    </Tooltip.Provider>
  );
}

function CitationBadge({ citation }: { citation: CitationType }) {
  return (
    <Tooltip.Provider>
      <Tooltip.Root>
        <Tooltip.Trigger asChild>
          <a
            href={citation.url}
            target="_blank"
            rel="noopener noreferrer"
            className="inline-flex items-center gap-2 px-3 py-2 bg-surface/40 hover:bg-surface/60 border border-border/50 hover:border-accent/30 rounded-xl transition-all group"
          >
            <span className="w-5 h-5 rounded-md bg-accent/15 text-accent flex items-center justify-center text-xs font-semibold">
              {citation.index}
            </span>
            {citation.favicon && (
              <img
                src={citation.favicon}
                alt=""
                className="w-4 h-4 rounded"
                onError={(e) => {
                  (e.target as HTMLImageElement).style.display = 'none';
                }}
              />
            )}
            <span className="text-sm text-secondary group-hover:text-primary max-w-[140px] truncate transition-colors">
              {citation.domain}
            </span>
            <ExternalLink className="w-3 h-3 text-muted group-hover:text-secondary transition-colors" />
          </a>
        </Tooltip.Trigger>
        <Tooltip.Portal>
          <Tooltip.Content
            side="top"
            className="max-w-[300px] p-4 bg-surface/95 backdrop-blur-xl border border-border rounded-xl shadow-dropdown z-50"
            sideOffset={8}
          >
            <p className="font-medium text-sm text-primary line-clamp-2 mb-2">
              {citation.title}
            </p>
            {citation.snippet && (
              <p className="text-xs text-secondary line-clamp-2 mb-2">
                {citation.snippet}
              </p>
            )}
            <p className="text-xs text-muted truncate">{citation.url}</p>
            <Tooltip.Arrow className="fill-surface" />
          </Tooltip.Content>
        </Tooltip.Portal>
      </Tooltip.Root>
    </Tooltip.Provider>
  );
}