#!/usr/bin/env node

/**
 * Plan Persistence Manager
 *
 * Tracks planning discussions and ensures plans are persisted to MD files.
 * Part of the enforcement mechanism for inst_comm_plan_001.
 *
 * INCIDENT REFERENCE: 2025-12-01 lost plan documentation
 *
 * Three functions:
 * 1. detectPlanningDiscussion(userMessage) - Detect if user is starting a plan
 * 2. trackPlanInProgress(sessionId, planTopic) - Mark a plan as in progress
 * 3. checkUnpersistedPlans(sessionId) - Check for plans not yet saved to MD
 * 4. markPlanPersisted(sessionId, planTopic, filePath) - Mark plan as saved
 */

const fs = require('fs');
const path = require('path');

// Session state file for tracking plans
const SESSION_STATE_DIR = path.join(__dirname, '..', 'session-state');
const PLANS_STATE_FILE = path.join(SESSION_STATE_DIR, 'plans-in-progress.json');

// Planning keywords that indicate a planning discussion
const PLANNING_KEYWORDS = [
  // Direct plan requests
  'create a plan',
  'make a plan',
  'write a plan',
  'document the plan',
  'save the plan',
  'outline the plan',
  'plan for',
  'planning',

  // Strategy discussions
  'strategy',
  'roadmap',
  'approach',
  'how should we',
  'let\'s discuss',
  'let\'s figure out',
  'design the',
  'architect',

  // Implementation discussions
  'implement',
  'implementation plan',
  'step by step',
  'phases',
  'milestones',

  // Feature discussions
  'redesign',
  'new feature',
  'feature request',
  'requirements',
  'spec',
  'specification',

  // Decision discussions
  'decision',
  'decide',
  'trade-offs',
  'options',
  'alternatives',
  'pros and cons',

  // Explicit requests to document
  'document this',
  'write this up',
  'save this',
  'record this',
  'keep a record',
  'md file',
  'markdown file'
];

// High-priority keywords that ALWAYS trigger plan tracking
const HIGH_PRIORITY_KEYWORDS = [
  'document the plan',
  'save the plan',
  'write a plan',
  'md file',
  'markdown file',
  'keep a record',
  'document this discussion'
];

/**
 * Ensure session state directory exists
 */
function ensureStateDir() {
  if (!fs.existsSync(SESSION_STATE_DIR)) {
    fs.mkdirSync(SESSION_STATE_DIR, { recursive: true });
  }
}

/**
 * Load current plans state
 */
function loadPlansState() {
  ensureStateDir();

  if (fs.existsSync(PLANS_STATE_FILE)) {
    try {
      return JSON.parse(fs.readFileSync(PLANS_STATE_FILE, 'utf-8'));
    } catch {
      return { plans: [], lastUpdated: null };
    }
  }

  return { plans: [], lastUpdated: null };
}

/**
 * Save plans state
 */
function savePlansState(state) {
  ensureStateDir();
  state.lastUpdated = new Date().toISOString();
  fs.writeFileSync(PLANS_STATE_FILE, JSON.stringify(state, null, 2));
}

/**
 * Detect if a message indicates a planning discussion
 *
 * @param {string} userMessage - The user's message
 * @returns {Object} - { isPlanningDiscussion, confidence, topic, isHighPriority }
 */
function detectPlanningDiscussion(userMessage) {
  if (!userMessage || typeof userMessage !== 'string') {
    return { isPlanningDiscussion: false, confidence: 0, topic: null, isHighPriority: false };
  }

  const lowerMessage = userMessage.toLowerCase();

  // Check high-priority keywords first
  const isHighPriority = HIGH_PRIORITY_KEYWORDS.some(keyword =>
    lowerMessage.includes(keyword)
  );

  if (isHighPriority) {
    // Extract topic from message (first 50 chars after keyword)
    const topic = extractTopic(userMessage);
    return {
      isPlanningDiscussion: true,
      confidence: 0.95,
      topic,
      isHighPriority: true
    };
  }

  // Check regular planning keywords
  const matchedKeywords = PLANNING_KEYWORDS.filter(keyword =>
    lowerMessage.includes(keyword)
  );

  if (matchedKeywords.length >= 2) {
    // Multiple keyword matches = high confidence
    return {
      isPlanningDiscussion: true,
      confidence: 0.85,
      topic: extractTopic(userMessage),
      isHighPriority: false
    };
  }

  if (matchedKeywords.length === 1) {
    // Single keyword match = medium confidence
    return {
      isPlanningDiscussion: true,
      confidence: 0.6,
      topic: extractTopic(userMessage),
      isHighPriority: false
    };
  }

  return { isPlanningDiscussion: false, confidence: 0, topic: null, isHighPriority: false };
}

/**
 * Extract a topic from a message
 */
function extractTopic(message) {
  // Take first 100 chars, remove special characters, truncate to first sentence
  let topic = message.substring(0, 100)
    .replace(/[^\w\s-]/g, ' ')
    .replace(/\s+/g, ' ')
    .trim();

  // Find first sentence boundary
  const sentenceEnd = topic.search(/[.!?]/);
  if (sentenceEnd > 10) {
    topic = topic.substring(0, sentenceEnd);
  }

  return topic || 'Unnamed Plan';
}

/**
 * Track a plan as in progress
 *
 * @param {string} sessionId - Current session ID
 * @param {string} topic - Plan topic
 * @param {number} confidence - Detection confidence
 * @param {boolean} isHighPriority - Whether this is a high-priority plan request
 */
function trackPlanInProgress(sessionId, topic, confidence = 0.8, isHighPriority = false) {
  const state = loadPlansState();

  // Check if plan already tracked
  const existingPlan = state.plans.find(p =>
    p.sessionId === sessionId && p.topic === topic
  );

  if (existingPlan) {
    // Update existing plan
    existingPlan.lastMentioned = new Date().toISOString();
    existingPlan.mentionCount = (existingPlan.mentionCount || 1) + 1;
    if (isHighPriority && !existingPlan.isHighPriority) {
      existingPlan.isHighPriority = true;
    }
  } else {
    // Add new plan
    state.plans.push({
      sessionId,
      topic,
      confidence,
      isHighPriority,
      startedAt: new Date().toISOString(),
      lastMentioned: new Date().toISOString(),
      mentionCount: 1,
      persisted: false,
      persistedTo: null
    });
  }

  savePlansState(state);

  return state.plans.find(p => p.sessionId === sessionId && p.topic === topic);
}

/**
 * Check for unpersisted plans in current session
 *
 * @param {string} sessionId - Current session ID
 * @returns {Object} - { hasUnpersistedPlans, plans, warningMessage }
 */
function checkUnpersistedPlans(sessionId) {
  const state = loadPlansState();

  const unpersistedPlans = state.plans.filter(p =>
    p.sessionId === sessionId && !p.persisted
  );

  if (unpersistedPlans.length === 0) {
    return { hasUnpersistedPlans: false, plans: [], warningMessage: null };
  }

  // Check if any are high priority
  const highPriorityPlans = unpersistedPlans.filter(p => p.isHighPriority);

  let warningMessage;

  if (highPriorityPlans.length > 0) {
    warningMessage = `⚠️  CRITICAL: User explicitly requested plan documentation that has NOT been saved:\n` +
      highPriorityPlans.map(p => `  • "${p.topic}" (requested ${p.mentionCount} times)`).join('\n') +
      `\n\n🚨 INSTRUCTION inst_comm_plan_001 REQUIRES: Save plans to docs/plans/PLAN_[TOPIC]_[YYYYMMDD].md IMMEDIATELY.` +
      `\n   DO NOT proceed with other work until this is done.`;
  } else {
    warningMessage = `📋 REMINDER: ${unpersistedPlans.length} plan(s) in progress may need to be saved:\n` +
      unpersistedPlans.map(p => `  • "${p.topic}"`).join('\n') +
      `\n\n   Per inst_comm_plan_001: Save significant plans to docs/plans/ directory.`;
  }

  return {
    hasUnpersistedPlans: true,
    plans: unpersistedPlans,
    warningMessage,
    hasHighPriority: highPriorityPlans.length > 0
  };
}

/**
 * Mark a plan as persisted
 *
 * @param {string} sessionId - Current session ID
 * @param {string} topic - Plan topic (partial match supported)
 * @param {string} filePath - Path where plan was saved
 */
function markPlanPersisted(sessionId, topic, filePath) {
  const state = loadPlansState();

  // Find matching plan (partial topic match)
  const plan = state.plans.find(p =>
    p.sessionId === sessionId &&
    !p.persisted &&
    (p.topic.toLowerCase().includes(topic.toLowerCase()) ||
     topic.toLowerCase().includes(p.topic.toLowerCase()))
  );

  if (plan) {
    plan.persisted = true;
    plan.persistedTo = filePath;
    plan.persistedAt = new Date().toISOString();
    savePlansState(state);
    return true;
  }

  return false;
}

/**
 * Check if a file write is a plan persistence
 *
 * @param {string} filePath - Path being written
 * @param {string} sessionId - Current session ID
 */
function checkPlanPersistence(filePath, sessionId) {
  // Check if writing to docs/plans/
  if (filePath && filePath.includes('docs/plans/') && filePath.endsWith('.md')) {
    const state = loadPlansState();

    // Find any unpersisted plans for this session
    const unpersistedPlans = state.plans.filter(p =>
      p.sessionId === sessionId && !p.persisted
    );

    // Mark the most recent/relevant one as persisted
    if (unpersistedPlans.length > 0) {
      // Mark all unpersisted plans as potentially persisted by this file
      unpersistedPlans.forEach(plan => {
        plan.persisted = true;
        plan.persistedTo = filePath;
        plan.persistedAt = new Date().toISOString();
      });

      savePlansState(state);

      return {
        markedAsPersisted: true,
        plansUpdated: unpersistedPlans.length,
        message: `✅ Plan(s) marked as persisted to: ${filePath}`
      };
    }
  }

  return { markedAsPersisted: false };
}

/**
 * Get session statistics
 */
function getSessionStats(sessionId) {
  const state = loadPlansState();

  const sessionPlans = state.plans.filter(p => p.sessionId === sessionId);
  const persisted = sessionPlans.filter(p => p.persisted);
  const unpersisted = sessionPlans.filter(p => !p.persisted);

  return {
    totalPlans: sessionPlans.length,
    persisted: persisted.length,
    unpersisted: unpersisted.length,
    plans: sessionPlans
  };
}

/**
 * Clean up old session plans (older than 24 hours)
 */
function cleanupOldPlans() {
  const state = loadPlansState();
  const cutoff = Date.now() - (24 * 60 * 60 * 1000); // 24 hours

  state.plans = state.plans.filter(p => {
    const planDate = new Date(p.startedAt).getTime();
    return planDate > cutoff;
  });

  savePlansState(state);
}

// Export functions
module.exports = {
  detectPlanningDiscussion,
  trackPlanInProgress,
  checkUnpersistedPlans,
  markPlanPersisted,
  checkPlanPersistence,
  getSessionStats,
  cleanupOldPlans,
  PLANNING_KEYWORDS,
  HIGH_PRIORITY_KEYWORDS
};

// CLI mode for testing
if (require.main === module) {
  const args = process.argv.slice(2);
  const command = args[0];

  switch (command) {
    case 'detect':
      const message = args.slice(1).join(' ');
      console.log(JSON.stringify(detectPlanningDiscussion(message), null, 2));
      break;

    case 'check':
      const sessionId = args[1] || 'test-session';
      console.log(JSON.stringify(checkUnpersistedPlans(sessionId), null, 2));
      break;

    case 'stats':
      const statsSessionId = args[1] || 'test-session';
      console.log(JSON.stringify(getSessionStats(statsSessionId), null, 2));
      break;

    case 'cleanup':
      cleanupOldPlans();
      console.log('Old plans cleaned up');
      break;

    default:
      console.log('Usage: node plan-persistence-manager.js <detect|check|stats|cleanup> [args]');
  }
}