import { createLogger } from '../utils/logger';
import { getContext, updateContext } from '../utils/contextStore';
import { getLlmClient } from '../llm/llmRouter';
import { productManagerPrompt, jsonRepairPrompt } from '../utils/promptTemplates';

const logger = createLogger('productManager');

const extractJsonFromResponse = (response: string): any | null => {
  // First try to parse the response directly
  try {
    return JSON.parse(response.trim());
  } catch {
    // If that fails, try to extract JSON from between thinking tags or from the end
    const lines = response.split('\n');
    let jsonStart = -1;
    
    // Look for the start of JSON (after thinking tags or just a { )
    for (let i = 0; i < lines.length; i++) {
      const line = lines[i].trim();
      if (line === '{' || line.startsWith('{"')) {
        jsonStart = i;
        break;
      }
      // Also check if this line contains </thinking> - JSON should be after this
      if (line.includes('</thinking>')) {
        jsonStart = i + 1;
        break;
      }
    }
    
    if (jsonStart >= 0) {
      const jsonLines = lines.slice(jsonStart);
      const potentialJson = jsonLines.join('\n').trim();
      
      try {
        return JSON.parse(potentialJson);
      } catch {
        // Try to find just the JSON object by looking for balanced braces
        const match = potentialJson.match(/\{[^{}]*(?:\{[^{}]*\}[^{}]*)*\}/g);
        if (match && match[0]) {
          try {
            return JSON.parse(match[0]);
          } catch {
            return null;
          }
        }
      }
    }
    
    return null;
  }
};

export const runProductManager = async () => {
  logger.start();
  const context = getContext();
  const { featurePrompt } = context;

  const llmClient = getLlmClient();
  const prompt = productManagerPrompt.replace('{{featurePrompt}}', featurePrompt);

  let response = await llmClient.generate(prompt);
  let spec = extractJsonFromResponse(response);

  if (!spec) {
    logger.error('Invalid JSON response from LLM. Attempting to repair...');
    const repairPrompt = jsonRepairPrompt.replace('{{invalidJson}}', response);
    response = await llmClient.generate(repairPrompt);
    spec = extractJsonFromResponse(response);
    
    if (!spec) {
      logger.error('Failed to repair JSON response. Skipping spec generation.');
      return {
        summary: 'Failed to generate product specification due to invalid LLM response',
        error: 'JSON parsing failed',
        completedAt: new Date().toISOString()
      };
    }
  }

  // Store spec in context for other agents to use
  updateContext({ spec });
  logger.stop();
  logger.success('Generated product spec.');
  
  // Return a condensed summary for the agent output (to avoid duplication)
  return {
    summary: `Product specification generated with ${spec.userStories?.length || 0} user stories and ${spec.acceptanceCriteria?.length || 0} acceptance criteria.`,
    title: spec.title,
    reasoning: response.includes('<thinking>') ? 'Used chain-of-thought reasoning' : 'Direct specification generation',
    completedAt: new Date().toISOString()
  };
};