import React, { createContext, useContext, useState, useCallback, ReactNode } from 'react';

export interface ChatMessage {
  id: string;
  role: 'user' | 'assistant';
  content: string;
  timestamp: number;
  type?: 'general' | 'agent' | 'compare';
  agentName?: string;
}

export interface toolsUser {
  email: string;
  id: string;
  is_active: boolean;
  is_superuser: boolean;
  is_verified: boolean;
  pages_limit: number;
  pages_used: string;
  yUserId: string;
}

interface ChatContextType {
  messages: ChatMessage[];
  addMessage: (role: 'user' | 'assistant', content: string, type?: 'general' | 'agent' | 'compare', agentName?: string) => void;
  clearMessages: () => void;
  deleteMessage: (id: string) => void;
  startConfig: unknown;
  setStartConfig: (val: unknown) => void;
  toolsUser: toolsUser | null;
  setToolsUser: (val: toolsUser) => void;
}

const ChatContext = createContext<ChatContextType | undefined>(undefined);

export function ChatProvider({ children }: { children: ReactNode }) {
  const [messages, setMessages] = useState<ChatMessage[]>(() => {
    try {
      const stored = localStorage.getItem('qa-chat-history');
      return stored ? JSON.parse(stored) : [];
    } catch {
      return [];
    }
  });

  const [startConfig, setStartConfig] = useState<unknown>(null);
  const [toolsUser, setToolsUser] = useState<toolsUser | null>(null);

  const saveToStorage = useCallback((newMessages: ChatMessage[]) => {
    try {
      localStorage.setItem('qa-chat-history', JSON.stringify(newMessages));
    } catch (error) {
      console.error('Failed to save chat history:', error);
    }
  }, []);

  const addMessage = useCallback((role: 'user' | 'assistant', content: string, type?: 'general' | 'agent' | 'compare', agentName?: string) => {
    const newMessage: ChatMessage = {
      id: `${Date.now()}-${Math.random().toString(36).substr(2, 9)}`,
      role,
      content,
      timestamp: Date.now(),
      type,
      agentName,
    };
    setMessages((prev) => {
      const updated = [...prev, newMessage];
      saveToStorage(updated);
      return updated;
    });
  }, [saveToStorage]);

  const clearMessages = useCallback(() => {
    setMessages([]);
    localStorage.removeItem('qa-chat-history');
  }, []);

  const deleteMessage = useCallback((id: string) => {
    setMessages((prev) => {
      const updated = prev.filter((msg) => msg.id !== id);
      saveToStorage(updated);
      return updated;
    });
  }, [saveToStorage]);

  return (
    <ChatContext.Provider
      value={{
        messages,
        addMessage,
        clearMessages,
        deleteMessage,
        startConfig,
        setStartConfig,
        toolsUser,
        setToolsUser,
      }}
    >
      {children}
    </ChatContext.Provider>
  );
}

export function useChatContext() {
  const context = useContext(ChatContext);
  if (context === undefined) {
    throw new Error('useChatContext must be used within a ChatProvider');
  }
  return context;
}