import express from 'express';
import cors from 'cors';
import path from 'path';
import fs from 'fs';
import { fileURLToPath } from 'url';

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

const app = express();
const PORT = process.env.PORT || 80;
const DATA_DIR = process.env.DATA_DIR || path.resolve(__dirname, '../data');

// Storage file paths
const TRIPS_FILE = path.join(DATA_DIR, 'trips.json');
const MEMORY_FILE = path.join(DATA_DIR, 'memory.json');
const SETTINGS_FILE = path.join(DATA_DIR, 'settings.json');

// Ensure storage directory exists
if (!fs.existsSync(DATA_DIR)) {
  fs.mkdirSync(DATA_DIR, { recursive: true });
}

// Helpers for safe file I/O
function readJson(file, defaultVal) {
  try {
    if (fs.existsSync(file)) {
      const data = fs.readFileSync(file, 'utf8');
      return JSON.parse(data);
    }
  } catch (err) {
    console.error(`Error reading ${file}:`, err);
  }
  return defaultVal;
}

function writeJson(file, data) {
  try {
    fs.writeFileSync(file, JSON.stringify(data, null, 2), 'utf8');
  } catch (err) {
    console.error(`Error writing ${file}:`, err);
  }
}

// Seed default memory if empty
if (!fs.existsSync(MEMORY_FILE)) {
  writeJson(MEMORY_FILE, {
    exclusions: [
      { itemName: 'Heavy winter coat', tripType: 'weekend_getaway', count: 1, lastDate: '2026-08-10' },
      { itemName: 'Full size hair dryer', tripType: 'beach', count: 2, lastDate: '2026-07-14' },
      { itemName: 'Extra pair of dress shoes', tripType: 'business', count: 1, lastDate: '2026-09-02' },
    ],
    inclusions: [
      {
        itemName: 'Packable laundry detergent sheets',
        category: 'clothing',
        defaultBag: 'carry_on',
        tripType: 'international_urban',
        count: 2,
        lastDate: '2026-06-20',
        reason: 'Saves hotel laundry fees; perfect for sink-washing socks/shirts',
      },
      {
        itemName: 'Compact 3-prong outlet splitter',
        category: 'tech',
        defaultBag: 'personal_item',
        tripType: 'business',
        count: 2,
        lastDate: '2026-09-02',
        reason: 'Airport and hotel outlets are always limited or loose',
      },
    ],
    totalTripsDebriefed: 2,
  });
}

// Middleware
app.use(cors());
app.use(express.json({ limit: '10mb' }));
app.use(express.urlencoded({ extended: true, limit: '10mb' }));

// Healthcheck endpoint for Docker & Traefik
app.get('/api/health', (_req, res) => {
  res.json({
    status: 'ok',
    app: 'loadout',
    timestamp: new Date().toISOString(),
    uptimeSeconds: Math.floor(process.uptime()),
  });
});

// GET /api/trips
app.get('/api/trips', (_req, res) => {
  const trips = readJson(TRIPS_FILE, []);
  res.json(trips);
});

// POST /api/trips
app.post('/api/trips', (req, res) => {
  const trip = req.body;
  if (!trip || !trip.id) {
    return res.status(400).json({ error: 'Invalid trip data' });
  }

  const trips = readJson(TRIPS_FILE, []);
  const index = trips.findIndex((t) => t.id === trip.id);
  if (index >= 0) {
    trips[index] = trip;
  } else {
    trips.unshift(trip);
  }

  writeJson(TRIPS_FILE, trips);
  res.json({ success: true, trip });
});

// DELETE /api/trips/:id
app.delete('/api/trips/:id', (req, res) => {
  const { id } = req.params;
  let trips = readJson(TRIPS_FILE, []);
  trips = trips.filter((t) => t.id !== id);
  writeJson(TRIPS_FILE, trips);
  res.json({ success: true });
});

// GET /api/memory
app.get('/api/memory', (_req, res) => {
  const memory = readJson(MEMORY_FILE, { exclusions: [], inclusions: [], totalTripsDebriefed: 0 });
  res.json(memory);
});

// POST /api/memory/debrief
app.post('/api/memory/debrief', (req, res) => {
  const { tripId, debrief } = req.body;
  if (!tripId || !debrief) {
    return res.status(400).json({ error: 'Missing tripId or debrief data' });
  }

  const trips = readJson(TRIPS_FILE, []);
  const trip = trips.find((t) => t.id === tripId);
  if (!trip) {
    return res.status(404).json({ error: 'Trip not found' });
  }

  trip.debrief = debrief;
  writeJson(TRIPS_FILE, trips);

  // Update memory
  const memory = readJson(MEMORY_FILE, { exclusions: [], inclusions: [], totalTripsDebriefed: 0 });
  memory.totalTripsDebriefed = (memory.totalTripsDebriefed || 0) + 1;

  // Record deadweight exclusions
  if (Array.isArray(debrief.excludedItemNames)) {
    for (const itemName of debrief.excludedItemNames) {
      const existing = memory.exclusions.find(
        (e) => e.tripType === trip.tripType && e.itemName.toLowerCase() === itemName.toLowerCase()
      );
      if (existing) {
        existing.count += 1;
        existing.lastDate = new Date().toISOString();
      } else {
        memory.exclusions.push({
          itemName,
          tripType: trip.tripType,
          count: 1,
          lastDate: new Date().toISOString(),
        });
      }
    }
  }

  // Record wishlist inclusions
  if (Array.isArray(debrief.includedItemNames)) {
    for (const itemName of debrief.includedItemNames) {
      const existing = memory.inclusions.find(
        (i) => i.tripType === trip.tripType && i.itemName.toLowerCase() === itemName.toLowerCase()
      );
      if (existing) {
        existing.count += 1;
        existing.lastDate = new Date().toISOString();
      } else {
        memory.inclusions.push({
          itemName,
          category: 'gear',
          defaultBag: 'carry_on',
          tripType: trip.tripType,
          count: 1,
          lastDate: new Date().toISOString(),
          reason: `Wished for after trip: ${trip.title}`,
        });
      }
    }
  }

  writeJson(MEMORY_FILE, memory);
  res.json({ success: true, memory });
});

// GET /api/settings
app.get('/api/settings', (_req, res) => {
  const settings = readJson(SETTINGS_FILE, {
    soundEnabled: true,
    compactView: false,
    aiEnabled: false,
    aiProvider: 'ollama',
    ollamaUrl: 'http://localhost:11434',
    ollamaModel: 'llama3.2',
    apiKey: '',
    customBags: [],
    customArchetypes: [],
  });
  res.json(settings);
});

// POST /api/settings
app.post('/api/settings', (req, res) => {
  const settings = req.body;
  writeJson(SETTINGS_FILE, settings);
  res.json({ success: true, settings });
});

// POST /api/ai/suggest
app.post('/api/ai/suggest', async (req, res) => {
  const { prompt, tripDetails } = req.body;
  const settings = readJson(SETTINGS_FILE, {});

  if (!settings.aiEnabled) {
    return res.status(400).json({ error: 'AI features are disabled in settings' });
  }

  try {
    if (settings.aiProvider === 'ollama') {
      const ollamaUrl = (settings.ollamaUrl || 'http://localhost:11434').replace(/\/$/, '');
      const response = await fetch(`${ollamaUrl}/api/generate`, {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({
          model: settings.ollamaModel || 'llama3.2',
          prompt: `You are a travel packing specialist. Based on this trip: ${JSON.stringify(tripDetails)}, suggest 3 to 5 hyper-specific, high-value packing items or travel wisdom tips. Respond in clear bullet points with concise reasoning.`,
          stream: false,
        }),
      });

      if (!response.ok) {
        throw new Error(`Ollama returned status ${response.status}`);
      }
      const data = await response.json();
      return res.json({ suggestion: data.response });
    }

    return res.status(400).json({ error: 'Configured AI provider not supported directly yet' });
  } catch (err) {
    console.error('AI suggest error:', err);
    return res.status(500).json({ error: 'Failed to communicate with AI provider: ' + err.message });
  }
});

// Serve frontend static build in production
const DIST_DIR = path.resolve(__dirname, '../dist');
if (fs.existsSync(DIST_DIR)) {
  app.use(express.static(DIST_DIR));
  app.use((req, res, next) => {
    if (req.method === 'GET' && !req.path.startsWith('/api')) {
      return res.sendFile(path.join(DIST_DIR, 'index.html'));
    }
    next();
  });
}

app.listen(PORT, '0.0.0.0', () => {
  console.log(`[LOADOUT] Server listening on port ${PORT}`);
  console.log(`[LOADOUT] Data directory: ${DATA_DIR}`);
});