import React, { useState, useEffect, useRef } from 'react';
import { Box, Text, useInput, useApp } from 'ink';
import TextInput from 'ink-text-input';
import AIResponse from './AIResponse.jsx';
import MarkdownText from './MarkdownText.jsx';
import { ThinkingSpinner } from './components/Spinner.jsx';

const ChatView = ({ chatSession, onComplete, onError, repomixSummary, aiAnalysis }) => {
  const { exit } = useApp();
  const [messages, setMessages] = useState([]);
  const [currentInput, setCurrentInput] = useState('');
  const [isWaitingForAI, setIsWaitingForAI] = useState(false);
  const [isStreamingAI, setIsStreamingAI] = useState(false);
  const [streamingContent, setStreamingContent] = useState('');
  const [mode, setMode] = useState('planning'); // 'planning', 'adr_generation', 'completed'
  const [featureDescription, setFeatureDescription] = useState('');
  const [isInitializing, setIsInitializing] = useState(true);
  const [inputMode, setInputMode] = useState('text'); // 'text' or 'selector'
  const [lastAIResponse, setLastAIResponse] = useState('');
  const scrollRef = useRef();

  // Helper function to start processing
  const startProcessing = () => {
    setIsWaitingForAI(true);
  };

  // Helper function to end processing
  const endProcessing = (response) => {
    setIsWaitingForAI(false);
    
    // Add the response as a message
    addMessage('assistant', response);
    
    // Check if this response has numbered options
    const hasNumberedOptions = response.match(/^\s*\d+\./m);
    
    if (hasNumberedOptions) {
      setLastAIResponse(response);
      setInputMode('selector');
    }
  };

  // Watch for AI analysis updates
  useEffect(() => {
    if (aiAnalysis && messages.length > 0) {
      // Check if AI analysis message already exists
      const hasAIAnalysis = messages.some(msg => 
        msg.type === 'assistant' && msg.content.includes('Codebase Analysis')
      );
      
      if (!hasAIAnalysis) {
        // Add AI analysis as a new message
        addMessage('assistant', aiAnalysis);
      }
    }
  }, [aiAnalysis]);

  // Initialize the chat session
  useEffect(() => {
    const initialize = async () => {
      try {
        setIsInitializing(true);
        
        
        // New session - include repomix summary and AI analysis
          const initialMessages = [];
          
          // Add repomix summary if available
          if (repomixSummary) {
            initialMessages.push({
              type: 'system',
              content: `📦 Repository Analysis Complete

Files processed: ${repomixSummary.fileCount.toLocaleString()}
Total lines: ${repomixSummary.totalLines.toLocaleString()}
Content size: ${repomixSummary.sizeKB} KB
Estimated tokens: ${repomixSummary.estimatedTokens.toLocaleString()}${repomixSummary.sampleFiles.length > 0 ? `

Sample files:
${repomixSummary.sampleFiles.map(file => `• ${file}`).join('\n')}${repomixSummary.hasMoreFiles ? `\n... and ${repomixSummary.remainingCount} more files` : ''}` : ''}`,
              timestamp: new Date()
            });
          }
          
          // Add ready message (no initial AI analysis)
          initialMessages.push({
            type: 'system',
            content: 'Ready to start feature planning! What feature would you like to build? (Type "done" when finished)',
            timestamp: new Date()
          });
          
          setMessages(initialMessages);
        
        setIsInitializing(false);
      } catch (error) {
        addMessage('system', `Error initializing chat: ${error.message}`);
        setIsInitializing(false);
        if (onError) {
          onError(error);
        }
      }
    };

    initialize();
  }, []);

  const addMessage = (type, content) => {
    setMessages(prev => [...prev, {
      type,
      content,
      timestamp: new Date()
    }]);
  };

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

    const userInput = input.trim();
    addMessage('user', userInput);
    setCurrentInput('');
    setInputMode('text'); // Reset to text mode after user input

    // Handle different modes
    if (mode === 'completed') {
      await handleCompletedMode(userInput);
    } else if (mode === 'planning') {
      await handlePlanningMode(userInput);
    }
  };

  const handleOptionSelect = async (optionText, optionValue) => {
    // User selected an option from the AI response
    addMessage('user', optionText);
    setInputMode('text'); // Switch back to text mode
    setLastAIResponse(''); // Clear last AI response

    // Handle the selection based on current mode
    if (mode === 'planning') {
      await handlePlanningMode(optionText);
    } else if (mode === 'completed') {
      await handleCompletedMode(optionText);
    }
  };

  const handleContinueWithText = () => {
    // Switch from selector back to text input
    setInputMode('text');
    setLastAIResponse('');
  };

  const handleCompletedMode = async (input) => {
    const lowerInput = input.toLowerCase();
    
    if (lowerInput === 'review') {
      addMessage('system', 'Current ADR Content:');
      addMessage('system', '='.repeat(80));
      addMessage('assistant', chatSession.featureData.adr_content);
      addMessage('system', '='.repeat(80));
      addMessage('system', 'You can type "modify" to make changes or "exit" to finish.');
    } else if (lowerInput === 'modify') {
      setMode('modification');
      addMessage('system', 'ADR Modification Mode');
      addMessage('system', 'You can ask questions about the current ADR, request changes, or explore alternatives.');
      
      startProcessing();
      const aiResponse = await chatSession.sendMessage(
        `I would like to review and potentially modify the current ADR. Here is the current ADR content:\n\n${chatSession.featureData.adr_content}\n\nI may want to make changes, explore alternatives, or ask questions about this ADR. Please help me refine it based on my feedback.`
      );
      endProcessing(aiResponse);
    } else if (lowerInput === 'exit' || lowerInput === 'done') {
      onComplete(chatSession.featureData);
      exit();
    } else {
      addMessage('system', 'Available commands: "review", "modify", "exit"');
    }
  };

  const handlePlanningMode = async (input) => {
    if (input.toLowerCase() === 'done') {
      await generateADR();
      return;
    }

    try {
      // Show processing indicator
      setIsWaitingForAI(true);
      
      // If this is the initial feature description
      if (!featureDescription) {
        setFeatureDescription(input);
        
        // Update chat session feature data
        if (chatSession) {
          chatSession.featureData.name = chatSession.extractFeatureName(input);
          chatSession.featureData.description = input;
        }
        
        addMessage('system', 'Starting interactive planning session...');
      }
      
      // Send message to ChatSession and get response
      const response = await chatSession.sendMessage(input);
      
      // Clear waiting state
      setIsWaitingForAI(false);
      
      // End processing with the response
      endProcessing(response);
      
    } catch (error) {
      setIsWaitingForAI(false);
      addMessage('system', `Error in planning: ${error.message}`);
      console.error('Planning error:', error);
    }
  };

  // Helper function to build display text from parsed data
  const buildDisplayText = (questionData) => {
    let displayText = '';
    
    if (questionData.header) {
      displayText += `# ${questionData.header}\n\n`;
    }
    
    if (questionData.bodyText) {
      displayText += questionData.bodyText;
    }
    
    if (questionData.optionText) {
      displayText += `\n\n---\n\n**${questionData.optionText}**`;
    }
    
    return displayText;
  };

  const generateADR = async () => {
    try {
      setMode('adr_generation');
      addMessage('system', '📝 Generating Architecture Decision Record...');
      
      // Generate ADR prompt based on conversation history
      const adrPrompt = `Based on our conversation about "${featureDescription}", please generate a comprehensive Architecture Decision Record (ADR) that includes:

1. Context and problem statement
2. Decision made
3. Consequences (positive and negative)
4. Implementation plan with specific steps

Format it as a proper ADR document with clear sections.`;
      
      // Send the ADR generation request
      const adrResponse = await chatSession.sendMessage(adrPrompt);
      
      // Update chat session feature data
      if (chatSession) {
        chatSession.featureData.adr_content = adrResponse;
        chatSession.featureData.adr_title = chatSession.extractADRTitle(adrResponse) || featureDescription;
        chatSession.featureData.adrFilename = chatSession.generateADRFilename(chatSession.featureData.name || featureDescription);
        chatSession.featureData.implementation_plan = chatSession.extractImplementationPlan(adrResponse);
      }
      
      // Display the generated ADR
      addMessage('assistant', adrResponse);
      
      addMessage('system', '✅ ADR generation completed!');
      setMode('completed');
      
      // Call the completion handler to save ADR to file
      if (onComplete && chatSession) {
        try {
          await onComplete(chatSession.featureData);
        } catch (error) {
          addMessage('system', `⚠️  Warning: Failed to save ADR file: ${error.message}`);
        }
      }
    } catch (error) {
      addMessage('system', `Error generating ADR: ${error.message}`);
      console.error('ADR generation error:', error);
    }
  };

  // Handle keyboard shortcuts
  useInput((input, key) => {
    if (key.escape) {
      exit();
    }
  });

  if (isInitializing) {
    return (
      <Box flexDirection="column" padding={1}>
        <Text color="blue">🤖 Initializing chat session...</Text>
      </Box>
    );
  }

  return (
    <Box flexDirection="column" height="100%" padding={1}>
      {/* Header */}
      <Box borderStyle="single" paddingX={1} marginBottom={1}>
        <Text color="blue" bold>
          📊 Codeplot - Feature Planning Chat
        </Text>
        <Text color="gray"> (ESC to exit)</Text>
      </Box>

      {/* Chat messages */}
      <Box flexDirection="column" flexGrow={1} paddingX={1} ref={scrollRef}>
        {messages.map((message, index) => (
          <Box key={index} marginBottom={1}>
            <Box width={12}>
              <Text color={
                message.type === 'user' ? 'green' : 
                message.type === 'assistant' ? 'blue' : 
                'yellow'
              }>
                {message.type === 'user' ? '👤 You:' : 
                 message.type === 'assistant' ? '🤖 AI:' : 
                 '📋 System:'}
              </Text>
            </Box>
            <Box flexGrow={1}>
              {message.type === 'assistant' ? (
                <MarkdownText wrap="wrap">{message.content}</MarkdownText>
              ) : (
                <Text wrap="wrap">{message.content}</Text>
              )}
            </Box>
          </Box>
        ))}
        
        {isWaitingForAI && inputMode !== 'selector' && (
          <Box marginBottom={1}>
            <Box width={12}>
              <Text color="blue">🤖 AI:</Text>
            </Box>
            <Box flexGrow={1}>
              	<ThinkingSpinner />
            </Box>
          </Box>
        )}
      </Box>

      {/* Selector for AI responses with options */}
      {inputMode === 'selector' && lastAIResponse && (
        <Box borderStyle="single" borderColor="yellow" marginBottom={1}>
          <AIResponse 
            content={lastAIResponse}
            parsedData={null}
            onOptionSelect={handleOptionSelect}
            onContinue={handleContinueWithText}
          />
        </Box>
      )}

      {/* Input area */}
      {inputMode === 'text' && (
        <Box borderStyle="single" paddingX={1}>
          <Text color="gray">{'> '}</Text>
          <TextInput
            value={currentInput}
            onChange={setCurrentInput}
            onSubmit={handleSubmit}
            placeholder={
              mode === 'completed' ? 'Type "review", "modify", or "exit"' :
              mode === 'planning' ? 'Your response (or "done" to finish)' :
              'Type your message...'
            }
          />
        </Box>
      )}
    </Box>
  );
};

export default ChatView;