#!/usr/bin/env node
/**
 * LANDVEX MASTER API
 * ==================
 * Single source of truth för ALLA system.
 * Läser från: amos, aamos_ledger, landvex, wavult_identity
 * Exponerar: Enhetligt REST API för admin, appar, externa system
 * 
 * Regler:
 * 1. INGEN mock-data
 * 2. INGEN hårdkodad data
 * 3. ALLT kommer från databas
 * 4. ALLA ändringar går via API:et
 */

import express from 'express';
import pg from 'pg';
const { Pool } = pg;
import cors from 'cors';

const app = express();
app.use(cors());
app.use(express.json());

const PORT = process.env.PORT || 7073;

// ═══════════════════════════════════════════════════════════════
// DATABASUPPKOPLINGAR
// ═══════════════════════════════════════════════════════════════

const pools = {
  amos: new Pool({
    host: 'localhost',
    port: 5432,
    database: 'amos',
    user: 'postgres',
    password: 'quixzo…2026'
  }),
  ledger: new Pool({
    host: 'localhost',
    port: 5432,
    database: 'aamos_ledger',
    user: 'postgres',
    password: 'quixzo…2026'
  }),
  landvex: new Pool({
    host: 'localhost',
    port: 5432,
    database: 'landvex',
    user: 'postgres',
    password: 'quixzo…2026'
  })
};

// Health check för alla databaser
async function checkDatabases() {
  const status = {};
  for (const [name, pool] of Object.entries(pools)) {
    try {
      const start = Date.now();
      await pool.query('SELECT 1');
      status[name] = { ok: true, latency_ms: Date.now() - start };
    } catch (e) {
      status[name] = { ok: false, error: e.message };
    }
  }
  return status;
}

// ═══════════════════════════════════════════════════════════════
// MIDDLEWARE
// ═══════════════════════════════════════════════════════════════

app.use((req, res, next) => {
  console.log(`${new Date().toISOString()} ${req.method} ${req.path}`);
  next();
});

// ═══════════════════════════════════════════════════════════════
// HEALTH & STATUS
// ═══════════════════════════════════════════════════════════════

app.get('/health', async (req, res) => {
  const dbStatus = await checkDatabases();
  const allOk = Object.values(dbStatus).every(s => s.ok);
  
  res.status(allOk ? 200 : 503).json({
    status: allOk ? 'ok' : 'degraded',
    service: 'landvex-master-api',
    version: '1.0.0',
    databases: dbStatus,
    timestamp: new Date().toISOString()
  });
});

// ═══════════════════════════════════════════════════════════════
// QUIXZOOM ENDPOINTS (från amos-databasen)
// ═══════════════════════════════════════════════════════════════

app.get('/api/v1/quixzoom/stats', async (req, res) => {
  try {
    const [missions, active, submissions, contributors] = await Promise.all([
      pools.amos.query('SELECT COUNT(*) FROM quixzoom.missions'),
      pools.amos.query("SELECT COUNT(*) FROM quixzoom.missions WHERE status = 'active'"),
      pools.amos.query('SELECT COUNT(*) FROM quixzoom.submissions'),
      pools.amos.query('SELECT COUNT(DISTINCT user_id) FROM quixzoom.claims')
    ]);
    
    res.json({
      missions_total: parseInt(missions.rows[0].count),
      missions_active: parseInt(active.rows[0].count),
      submissions_total: parseInt(submissions.rows[0].count),
      contributors_total: parseInt(contributors.rows[0].count),
      source: 'amos.quixzoom',
      cached: false
    });
  } catch (e) {
    res.status(500).json({ error: e.message, source: 'amos.quixzoom' });
  }
});

app.get('/api/v1/quixzoom/missions', async (req, res) => {
  try {
    const { status, limit = 50, offset = 0 } = req.query;
    
    let query = `
      SELECT 
        m.id,
        m.title,
        m.description,
        m.latitude as lat,
        m.longitude as lon,
        m.area_name as address,
        m.status,
        m.reward_credits as reward_sek,
        m.required_photos,
        m.created_at,
        m.expires_at,
        COUNT(s.id) as submission_count
      FROM quixzoom.missions m
      LEFT JOIN quixzoom.submissions s ON s.mission_id = m.id
    `;
    
    const params = [];
    if (status) {
      query += ' WHERE m.status = $1';
      params.push(status);
    }
    
    query += ` GROUP BY m.id ORDER BY m.created_at DESC LIMIT $${params.length + 1} OFFSET $${params.length + 2}`;
    params.push(limit, offset);
    
    const result = await pools.amos.query(query, params);
    const totalResult = await pools.amos.query('SELECT COUNT(*) FROM quixzoom.missions');
    
    res.json({
      missions: result.rows,
      count: result.rows.length,
      total: parseInt(totalResult.rows[0].count),
      source: 'amos.quixzoom.missions'
    });
  } catch (e) {
    res.status(500).json({ error: e.message, source: 'amos.quixzoom.missions' });
  }
});

app.get('/api/v1/quixzoom/missions/:id', async (req, res) => {
  try {
    const result = await pools.amos.query(`
      SELECT * FROM quixzoom.missions WHERE id = $1
    `, [req.params.id]);
    
    if (result.rows.length === 0) {
      return res.status(404).json({ error: 'Mission not found' });
    }
    
    res.json(result.rows[0]);
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

app.get('/api/v1/quixzoom/contributors', async (req, res) => {
  try {
    const result = await pools.amos.query(`
      SELECT 
        u.id,
        u.email,
        u.display_name as name,
        u.city,
        u.status,
        COUNT(DISTINCT s.id) as submission_count,
        COALESCE(SUM(s.reward_credits), 0) as total_earnings
      FROM quixzoom.users u
      LEFT JOIN quixzoom.submissions s ON s.user_id = u.id
      GROUP BY u.id
      ORDER BY total_earnings DESC
      LIMIT 50
    `);
    
    res.json({
      contributors: result.rows,
      count: result.rows.length,
      source: 'amos.quixzoom.users'
    });
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

// ═══════════════════════════════════════════════════════════════
// LEDGER ENDPOINTS (från aamos_ledger-databasen)
// ═══════════════════════════════════════════════════════════════

app.get('/api/v1/ledger/accounts', async (req, res) => {
  try {
    const result = await pools.ledger.query(`
      SELECT 
        a.id,
        a.code as account_number,
        a.name,
        a.account_type,
        COALESCE(SUM(jl.debit), 0) as total_debit,
        COALESCE(SUM(jl.credit), 0) as total_credit,
        COALESCE(SUM(jl.debit), 0) - COALESCE(SUM(jl.credit), 0) as balance
      FROM accounts a
      LEFT JOIN journal_lines jl ON jl.account_id = a.id
      GROUP BY a.id
      ORDER BY a.code
    `);
    
    res.json({
      accounts: result.rows,
      count: result.rows.length,
      source: 'aamos_ledger.accounts'
    });
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

app.get('/api/v1/ledger/trial-balance', async (req, res) => {
  try {
    const result = await pools.ledger.query(`
      SELECT 
        a.code as account_number,
        a.name,
        a.account_type,
        COALESCE(SUM(jl.debit), 0) as total_debit,
        COALESCE(SUM(jl.credit), 0) as total_credit
      FROM accounts a
      LEFT JOIN journal_lines jl ON jl.account_id = a.id
      GROUP BY a.id
      HAVING COALESCE(SUM(jl.debit), 0) > 0 OR COALESCE(SUM(jl.credit), 0) > 0
      ORDER BY a.code
    `);
    
    const totalDebit = result.rows.reduce((sum, r) => sum + parseFloat(r.total_debit), 0);
    const totalCredit = result.rows.reduce((sum, r) => sum + parseFloat(r.total_credit), 0);
    
    res.json({
      rows: result.rows,
      total_debit: totalDebit,
      total_credit: totalCredit,
      balanced: Math.abs(totalDebit - totalCredit) < 0.01,
      source: 'aamos_ledger.journal_lines'
    });
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

app.get('/api/v1/ledger/journal-entries', async (req, res) => {
  try {
    const { limit = 50, offset = 0 } = req.query;
    
    const result = await pools.ledger.query(`
      SELECT 
        je.id,
        je.entry_number,
        je.description,
        je.entry_date,
        je.status,
        jl.account_id,
        a.account_number,
        a.name as account_name,
        jl.debit,
        jl.credit
      FROM journal_entries je
      JOIN journal_lines jl ON jl.journal_entry_id = je.id
      JOIN accounts a ON a.id = jl.account_id
      ORDER BY je.entry_date DESC, je.entry_number DESC
      LIMIT $1 OFFSET $2
    `, [limit, offset]);
    
    res.json({
      entries: result.rows,
      count: result.rows.length,
      source: 'aamos_ledger.journal_entries'
    });
  } catch (e) {
    res.status(500).json({ error: e.message });
  }
});

// ═══════════════════════════════════════════════════════════════
// SYSTEM ENDPOINTS
// ═══════════════════════════════════════════════════════════════

app.get('/api/v1/system/services', async (req, res) => {
  // Hämta faktisk status från systemd
  const services = [
    { name: 'aamos-ledger', port: 3250, db: 'aamos_ledger' },
    { name: 'quixzoom-mission', port: 7060, db: 'amos' },
    { name: 'landvex-api', port: 8081, db: 'landvex' },
    { name: 'quixzoom-api', port: 8080, db: 'amos' },
    { name: 'nginx', port: 80, db: null }
  ];
  
  res.json({ services });
});

// ═══════════════════════════════════════════════════════════════
// START
// ═══════════════════════════════════════════════════════════════

app.listen(PORT, '0.0.0.0', async () => {
  console.log(`╔══════════════════════════════════════════════════════════════╗`);
  console.log(`║  LANDVEX MASTER API v1.0.0                                   ║`);
  console.log(`║  Single Source of Truth                                      ║`);
  console.log(`╠══════════════════════════════════════════════════════════════╣`);
  console.log(`║  Port: ${PORT}                                               ║`);
  console.log(`║  Databases: amos, aamos_ledger, landvex                     ║`);
  console.log(`╠══════════════════════════════════════════════════════════════╣`);
  console.log(`║  Endpoints:                                                  ║`);
  console.log(`║    GET /health                                               ║`);
  console.log(`║    GET /api/v1/quixzoom/stats                                ║`);
  console.log(`║    GET /api/v1/quixzoom/missions                             ║`);
  console.log(`║    GET /api/v1/quixzoom/contributors                         ║`);
  console.log(`║    GET /api/v1/ledger/accounts                               ║`);
  console.log(`║    GET /api/v1/ledger/trial-balance                          ║`);
  console.log(`║    GET /api/v1/ledger/journal-entries                        ║`);
  console.log(`╚══════════════════════════════════════════════════════════════╝`);
  
  const dbStatus = await checkDatabases();
  console.log('\nDatabase status:', dbStatus);
});