"use client";
import React, { useState, useRef, useEffect } from 'react';
import {
  Send, Plus, Menu, Search, Archive, Trash2, Edit3,
  MessageSquare, User, Bot, Copy, ThumbsUp, ThumbsDown,
  RotateCcw, Share, MoreHorizontal, Image, Video, FileText,
  Code, Table, Music, Mic, Settings, Zap, Brain, Sparkles,
  BarChart2, Clock, Globe, Lock, Unlock, Book, Feather,
  Camera, Film, Headphones, Download, Upload, Link, Mail,
  AlertCircle, CheckCircle, HelpCircle, Info, Star, Heart,
  Award, Gift, Coffee, ShoppingCart, CreditCard, Key,
  Map, Navigation, Phone, Tag, Watch, Wifi,
  Cloud, Sun, Moon, Umbrella, Droplet, Wind
} from 'lucide-react';

const ChatPage = () => {
  const [messages, setMessages] = useState([
    {
      id: 1,
      type: 'assistant',
      content: "Hello! I'm General Bots, a large language model by Pragmatismo. How can I help you today?",
      timestamp: new Date().toISOString()
    }
  ]);
  const [input, setInput] = useState('');
  const [isTyping, setIsTyping] = useState(false);
  const [sidebarOpen, setSidebarOpen] = useState(true);
  const [conversations, setConversations] = useState([
    { id: 1, title: 'Current Chat', timestamp: new Date(), active: true },
    { id: 2, title: 'Previous Conversation', timestamp: new Date(Date.now() - 86400000), active: false },
    { id: 3, title: 'Code Review Discussion', timestamp: new Date(Date.now() - 172800000), active: false },
    { id: 4, title: 'Project Planning', timestamp: new Date(Date.now() - 259200000), active: false },
  ]);
  const [activeMode, setActiveMode] = useState('assistant');
  const messagesEndRef = useRef(null);
  const textareaRef = useRef(null);

  // Mode buttons
  const modeButtons = [
    { id: 'deep-think', icon: <Brain size={16} />, label: 'Deep Think' },
    { id: 'web', icon: <Globe size={16} />, label: 'Web' },
    { id: 'image', icon: <Image size={16} />, label: 'Image' },
    { id: 'video', icon: <Video size={16} />, label: 'Video' },
  ];

  const scrollToBottom = () => {
    messagesEndRef.current?.scrollIntoView({ behavior: 'smooth' });
  };

  useEffect(() => {
    scrollToBottom();
  }, [messages]);

  const handleSubmit = async () => {
    if (!input.trim()) return;

    const userMessage = {
      id: Date.now(),
      type: 'user',
      content: input.trim(),
      timestamp: new Date().toISOString()
    };

    setMessages(prev => [...prev, userMessage]);
    setInput('');
    setIsTyping(true);

    // Simulate assistant response
    setTimeout(() => {
      const assistantMessage = {
        id: Date.now() + 1,
        type: 'assistant',
        content: `I understand you're asking about "${input.trim()}". This is a simulated response to demonstrate the chat interface. The actual implementation would connect to your chat provider and send real responses.`,
        timestamp: new Date().toISOString()
      };
      setMessages(prev => [...prev, assistantMessage]);
      setIsTyping(false);
    }, 1500);
  };

  const handleKeyDown = (e) => {
    if (e.key === 'Enter' && !e.shiftKey) {
      e.preventDefault();
      handleSubmit();
    }
  };

  const formatTimestamp = (timestamp) => {
    const date = new Date(timestamp);
    const now = new Date();
    const diffInHours = (now - date) / (1000 * 60 * 60);

    if (diffInHours < 24) {
      return date.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
    } else if (diffInHours < 48) {
      return 'Yesterday';
    } else {
      return date.toLocaleDateString();
    }
  };

  const newChat = () => {
    const newConv = {
      id: Date.now(),
      title: 'New Chat',
      timestamp: new Date(),
      active: true
    };
    setConversations(prev => [newConv, ...prev.map(c => ({ ...c, active: false }))]);
    setMessages([{
      id: Date.now(),
      type: 'assistant',
      content: "Hello! I'm General Bots, a large language model by Pragmatismo. How can I help you today?",
      timestamp: new Date().toISOString()
    }]);
  };

  const MessageActions = ({ message }) => (
    <div className="flex items-center gap-1 opacity-0 group-hover:opacity-100 transition-opacity duration-200">
      <button className="p-1.5 hover:bg-secondary rounded-md transition-colors">
        <Copy className="w-3.5 h-3.5 text-muted-foreground" />
      </button>
      <button className="p-1.5 hover:bg-secondary rounded-md transition-colors">
        <ThumbsUp className="w-3.5 h-3.5 text-muted-foreground" />
      </button>
      <button className="p-1.5 hover:bg-secondary rounded-md transition-colors">
        <ThumbsDown className="w-3.5 h-3.5 text-muted-foreground" />
      </button>
      <button className="p-1.5 hover:bg-secondary rounded-md transition-colors">
        <Share className="w-3.5 h-3.5 text-muted-foreground" />
      </button>
    </div>
  );

  // Auto-resize textarea
  useEffect(() => {
    const textarea = textareaRef.current;
    if (textarea) {
      textarea.style.height = 'auto';
      textarea.style.height = `${Math.min(textarea.scrollHeight, 120)}px`;
    }
  }, [input]);

  return (
    <div className="flex min-h-[calc(100vh-43px)] bg-background text-foreground">
      {/* Sidebar */}
      <div
        className={`${
          sidebarOpen ? 'w-80' : 'w-0'
        } transition-all duration-300 ease-in-out bg-card border-r border-border flex flex-col overflow-hidden`}
      >
        {sidebarOpen && (
          <>
            {/* Sidebar Header */}
            <div className="p-4 border-b border-border flex-shrink-0">
              <button
                onClick={newChat}
                className="flex items-center gap-3 w-full p-3 rounded-xl border-2 border-dashed border-muted hover:border-accent hover:bg-accent/10 transition-all duration-200 group"
              >
                <Plus className="w-5 h-5 text-muted-foreground group-hover:text-accent" />
                <span className="font-medium text-foreground group-hover:text-accent">
                  New Chat
                </span>
              </button>
            </div>

            {/* Conversations List */}
            <div className="flex-1 overflow-hidden">
              <div className="h-full overflow-y-auto px-3 py-2 space-y-1">
                {conversations.map(conv => (
                  <div
                    key={conv.id}
                    className={`group relative flex items-center gap-3 p-3 rounded-xl cursor-pointer transition-all duration-200 ${
                      conv.active 
                        ? 'bg-primary/10 border border-primary' 
                        : 'hover:bg-secondary'
                    }`}
                    onClick={() => {
                      setConversations(prev => prev.map(c => ({ ...c, active: c.id === conv.id })));
                    }}
                  >
                    <MessageSquare className={`w-4 h-4 flex-shrink-0 ${
                      conv.active ? 'text-primary' : 'text-muted-foreground'
                    }`} />
                    <div className="flex-1 min-w-0">
                      <div className={`font-medium truncate ${
                        conv.active ? 'text-primary' : 'text-foreground'
                      }`}>
                        {conv.title}
                      </div>
                      <div className="text-xs text-muted-foreground truncate">
                        {formatTimestamp(conv.timestamp)}
                      </div>
                    </div>
                    {conv.active && (
                      <div className="w-2 h-2 rounded-full bg-primary flex-shrink-0"></div>
                    )}
                  </div>
                ))}
              </div>
            </div>

            {/* Sidebar Footer */}
            <div className="p-4 border-t border-border flex-shrink-0">
              <div className="flex items-center gap-3 p-3 rounded-xl hover:bg-secondary cursor-pointer transition-colors duration-200">
                <User className="w-5 h-5 text-muted-foreground" />
                <User className="w-5 h-5 text-muted-foreground" />
                <User className="w-5 h-5 text-muted-foreground" />
                <User className="w-5 h-5 text-muted-foreground" />
                <User className="w-5 h-5 text-muted-foreground" />
              </div>
            </div>
          </>
        )}
      </div>

      {/* Main Chat Area */}
      <div className="flex-1 flex flex-col min-w-0 bg-background">
        {/* Header */}
        <div className="flex-shrink-0 p-4 border-b border-border bg-card">
          <div className="flex items-center justify-between">
            <div className="flex items-center gap-4">
              <button
                onClick={() => setSidebarOpen(!sidebarOpen)}
                className="p-2 hover:bg-secondary rounded-lg transition-colors duration-200"
              >
                <Menu className="w-5 h-5" />
              </button>
              <h1 className="text-xl font-semibold text-foreground">
                {conversations.find(c => c.active)?.title || 'New Chat'}
              </h1>
            </div>
            <button className="p-2 hover:bg-secondary rounded-lg transition-colors duration-200">
              <Search className="w-5 h-5" />
            </button>
          </div>
        </div>

        {/* Messages Container */}
        <div className="flex-1 overflow-hidden flex flex-col">
          <div className="flex-1 overflow-y-auto px-4 py-6 space-y-6">
            {messages.map(message => (
              <div
                key={message.id}
                className={`group flex ${message.type === 'user' ? 'justify-end' : 'justify-start'}`}
              >
                <div className={`max-w-[85%] md:max-w-[75%] ${
                  message.type === 'user' 
                    ? 'bg-primary text-primary-foreground' 
                    : 'bg-secondary text-secondary-foreground'
                } rounded-2xl px-4 py-3 shadow-sm`}>
                  <div className="flex items-start gap-3">
                    <div className="flex-shrink-0 mt-0.5">
                      {message.type === 'user' ? (
                        <User className="w-4 h-4" />
                      ) : (
                        <Bot className="w-4 h-4" />
                      )}
                    </div>
                    <div className="flex-1 min-w-0">
                      <div className="whitespace-pre-wrap break-words leading-relaxed">
                        {message.content}
                      </div>
                      <div className={`mt-3 flex items-center justify-between text-xs ${
                        message.type === 'user' 
                          ? 'text-primary-foreground/80' 
                          : 'text-muted-foreground'
                      }`}>
                        <span>{formatTimestamp(message.timestamp)}</span>
                        {message.type === 'assistant' && <MessageActions message={message} />}
                      </div>
                    </div>
                  </div>
                </div>
              </div>
            ))}
            
            {isTyping && (
              <div className="flex justify-start">
                <div className="max-w-[85%] md:max-w-[75%] bg-secondary rounded-2xl px-4 py-3 shadow-sm">
                  <div className="flex items-center gap-3">
                    <Bot className="w-4 h-4 text-muted-foreground" />
                    <div className="flex gap-1">
                      <div className="w-2 h-2 rounded-full bg-muted-foreground animate-bounce"></div>
                      <div className="w-2 h-2 rounded-full bg-muted-foreground animate-bounce" style={{ animationDelay: '0.2s' }}></div>
                      <div className="w-2 h-2 rounded-full bg-muted-foreground animate-bounce" style={{ animationDelay: '0.4s' }}></div>
                    </div>
                  </div>
                </div>
              </div>
            )}
            <div ref={messagesEndRef} />
          </div>
        </div>

        {/* Mode Carousel */}
        <div className="flex-shrink-0 border-t border-border bg-card">
          <div className="overflow-x-auto px-4 py-3">
            <div className="flex gap-2 min-w-max">
              {modeButtons.map(button => (
                <button
                  key={button.id}
                  onClick={() => setActiveMode(button.id)}
                  className={`flex items-center gap-2 px-4 py-2 rounded-full text-sm font-medium transition-all duration-200 whitespace-nowrap ${
                    activeMode === button.id
                      ? 'bg-primary/10 text-primary border border-primary'
                      : 'bg-secondary text-secondary-foreground hover:bg-secondary/80'
                  }`}
                >
                  {button.icon}
                  <span>{button.label}</span>
                </button>
              ))}
            </div>
          </div>
        </div>

        {/* Input Area */}
        <div className="flex-shrink-0 p-4 border-t border-border bg-card">
          <div className="relative max-w-4xl mx-auto">
            <textarea
              ref={textareaRef}
              value={input}
              onChange={(e) => setInput(e.target.value)}
              onKeyDown={handleKeyDown}
              placeholder="Type your message..."
              className="w-full p-4 pr-14 rounded-2xl border border-input bg-background text-foreground placeholder:text-muted-foreground focus:outline-none focus:ring-2 focus:ring-ring focus:border-transparent resize-none transition-all duration-200"
              rows={1}
              style={{ minHeight: '56px', maxHeight: '120px' }}
            />
            <button
              onClick={handleSubmit}
              disabled={!input.trim()}
              className={`absolute right-6 bottom-3 p-2.5 rounded-xl transition-all duration-200 ${
                input.trim()
                  ? 'bg-primary hover:bg-primary/90 text-primary-foreground shadow-lg hover:shadow-xl transform hover:scale-105'
                  : 'bg-muted text-muted-foreground cursor-not-allowed'
              }`}
            >
              <Send className="w-5 h-5 " />
            </button>
          </div>
        </div>
      </div>
    </div>
  );
};

export default ChatPage;