'use strict';

const express  = require('express');
const path     = require('path');
const fs       = require('fs');
const multer   = require('multer');
const XLSX     = require('xlsx');
const { v4: uuidv4 } = require('uuid');

const app        = express();
const PORT       = process.env.ADMIN_TOKEN || 3101;
const ADMIN_TOKEN= process.env.ADMIN_TOKEN || 'loreal2024';
const STATIC_DIR = path.join(__dirname, '..');
const SPECS_FILE = path.join(STATIC_DIR, 'specs.json');

const upload = multer({ storage: multer.memoryStorage(), limits: { fileSize: 20 * 1024 * 1024 } });

app.use(express.json({ limit: '10mb' }));
app.set('trust proxy', 1);

// ── Auth middleware ───────────────────────────────────────────────────────────
function requireAdmin(req, res, next) {
  if (req.headers['x-admin-token'] !== ADMIN_TOKEN) {
    return res.status(401).json({ error: 'Unauthorized' });
  }
  next();
}

// ── Health ────────────────────────────────────────────────────────────────────
app.get('/api/health', (_req, res) => res.json({ status: 'ok', specs: loadSpecs().specs.length }));

// ── Get specs ─────────────────────────────────────────────────────────────────
app.get('/api/specs', (_req, res) => res.json(loadSpecs()));

// ── Save specs ────────────────────────────────────────────────────────────────
app.post('/api/specs', requireAdmin, (req, res) => {
  const data = req.body;
  if (!data || !Array.isArray(data.specs)) return res.status(400).json({ error: 'Invalid payload' });
  try {
    fs.writeFileSync(SPECS_FILE, JSON.stringify(data, null, 2), 'utf8');
    res.json({ ok: true, totalSpecs: data.specs.length });
  } catch (e) {
    console.error('Write error:', e);
    res.status(500).json({ error: 'Failed to save specs' });
  }
});

// ── Parse uploaded file (Excel or CSV) ───────────────────────────────────────
app.post('/api/import/parse', requireAdmin, upload.single('file'), (req, res) => {
  if (!req.file) return res.status(400).json({ error: 'No file uploaded' });

  try {
    const wb   = XLSX.read(req.file.buffer, { type: 'buffer' });
    const ws   = wb.Sheets[wb.SheetNames[0]];
    const rows = XLSX.utils.sheet_to_json(ws, { defval: '' });

    // Normalise: try row 0 as headers, if it looks like a title row skip it
    let dataRows = rows;
    if (rows.length && typeof rows[0] === 'object') {
      const firstKey = Object.keys(rows[0])[0] || '';
      // If first row looks like a title (no COUNTRY/RETAILER key), try raw with header row
      if (!firstKey.toUpperCase().includes('COUNTRY') && !firstKey.toUpperCase().includes('RETAILER')) {
        const raw    = XLSX.utils.sheet_to_json(ws, { header: 1, defval: '' });
        // Find the header row (first row that contains COUNTRY or RETAILER)
        let headerIdx = 0;
        for (let i = 0; i < Math.min(5, raw.length); i++) {
          const rowStr = raw[i].join(' ').toUpperCase();
          if (rowStr.includes('COUNTRY') || rowStr.includes('RETAILER')) { headerIdx = i; break; }
        }
        const headers  = raw[headerIdx].map(h => String(h).trim());
        dataRows = raw.slice(headerIdx + 1)
          .filter(r => r.some(c => c !== ''))
          .map(r => Object.fromEntries(headers.map((h, i) => [h, String(r[i] || '').trim()])));
      }
    }

    const today = new Date().toISOString().split('T')[0];
    const parsed = dataRows
      .filter(r => getField(r, ['RETAILER', 'retailer', 'Retailer']) ||
                   getField(r, ['FORMAT', 'format', 'Format', 'FORMAT NAME', 'format name']))
      .map(r => {
        const fileTypesRaw = getField(r, ['FILE TYPE', 'file type', 'File Type', 'fileType', 'file_type', 'FILE_TYPE']);
        return {
          id:              uuidv4(),
          country:         getField(r, ['COUNTRY', 'country', 'Country']),
          retailer:        getField(r, ['RETAILER', 'retailer', 'Retailer']),
          contentGrouping: getField(r, ['ECOM CONTENT GROUPING', 'Content Grouping', 'contentGrouping', 'content_grouping', 'CONTENT GROUPING', 'category', 'Category']),
          division:        getField(r, ['DIVISION', 'division', 'Division']),
          format:          getField(r, ['FORMAT', 'format', 'Format', 'FORMAT NAME', 'format name', 'Format Name']),
          dimensions:      getField(r, ['ASSET DIMENSION', 'dimensions', 'Dimensions', 'dimension', 'size', 'Size', 'DIMENSIONS']),
          maxWeight:       getField(r, ['ASSET WEIGHT', 'maxWeight', 'max weight', 'Max Weight', 'file size', 'File Size', 'MAX WEIGHT']),
          fileTypes:       splitFileTypes(fileTypesRaw),
          fileTypesRaw,
          maxAssets:       getField(r, ['MAX NUMBER OF ASSETS', 'maxAssets', 'max assets', 'Max Assets', 'MAX ASSETS']),
          guidelines:      getField(r, ['RETAILER ASSET GUIDELINES', 'guidelines', 'Guidelines', 'GUIDELINES', 'notes', 'Notes']),
          deliveryMethod:  getField(r, ['DELIVERY METHOD FOR SYNDICATION', 'deliveryMethod', 'delivery method', 'Delivery Method']),
          deliveryDetail:  getField(r, ['DETAILED', 'deliveryDetail', 'delivery detail', 'Delivery Detail', 'delivery', 'Delivery']),
          handledBy:       getField(r, ['HANDLED BY (WIP)', 'handledBy', 'handled by', 'Handled By']),
          namingConvention:getField(r, ['FILE NAMING CONVENTION FOR RETAILER', 'namingConvention', 'naming convention', 'Naming Convention', 'file naming', 'File Naming']),
          uploadLink:      getField(r, ['LINKS FOR UPLOAD', 'uploadLink', 'upload link', 'Upload Link']),
          imageExample:    getField(r, ['IMAGE EXAMPLE', 'imageExample', 'image example', 'Image Example']),
          notes:           getField(r, ['notes', 'Notes', 'NOTES', 'additional notes', 'Additional Notes']),
          updatedAt:       today,
          lastVerified:    today,
        };
      });

    res.json({ ok: true, parsed, count: parsed.length });
  } catch (e) {
    console.error('Parse error:', e);
    res.status(500).json({ error: `Failed to parse file: ${e.message}` });
  }
});

// ── Static files ──────────────────────────────────────────────────────────────
app.use(express.static(STATIC_DIR, { index: 'index.html' }));
app.get('*', (_req, res) => res.sendFile(path.join(STATIC_DIR, 'index.html')));

app.use((err, _req, res, _next) => {
  console.error(err);
  res.status(500).json({ error: 'Internal server error' });
});

app.listen(process.env.PORT || 3101, () => {
  console.log(`L'Oréal Spec Tool running on port ${process.env.PORT || 3101}`);
});

// ── Helpers ───────────────────────────────────────────────────────────────────
function loadSpecs() {
  try { return JSON.parse(fs.readFileSync(SPECS_FILE, 'utf8')); }
  catch { return { specs: [], meta: {} }; }
}

function getField(row, keys) {
  for (const k of keys) {
    if (row[k] !== undefined && row[k] !== null) {
      const v = String(row[k]).trim();
      if (v && !['NO INFO', 'N/A', '-'].includes(v)) return v;
    }
  }
  return '';
}

function splitFileTypes(raw) {
  if (!raw) return [];
  const known = new Set(['JPG','JPEG','PNG','TIFF','TIF','PSD','WEBP','SVG','ZIP','PDF','GIF','MP4','MOV','AVI']);
  return [...new Set(
    raw.toUpperCase().split(/[\s,/|]+/)
      .map(p => p.replace(/[^A-Z]/g, ''))
      .filter(p => known.has(p))
  )];
}