import { applyCors, isAllowedOrigin } from './_cors.js';
import { createClient } from '@supabase/supabase-js';

const SUPABASE_URL = process.env.SUPABASE_URL || 'https://hwithddwaapyhnfwcesj.supabase.co';
const SUPABASE_KEY = process.env.SUPABASE_SERVICE_ROLE_KEY || process.env.SUPABASE_SERVICE_KEY || 'sb_publishable_fGXkh0bSrAOqSk2jWKAzSg_NJD9YPCv';

const supabase = createClient(SUPABASE_URL, SUPABASE_KEY);

function setCors(req, res) {
  applyCors(req, res, 'POST, OPTIONS');
}

export default async function handler(req, res) {
  setCors(req, res);

  if (req.method === 'OPTIONS') {
    return res.status(204).end();
  }

  const origin = req.headers.origin;
  if (origin && !isAllowedOrigin(origin)) {
    return res.status(403).json({ error: 'Forbidden' });
  }

  try {
    if (req.method !== 'POST') {
      return res.status(405).json({ error: 'Method not allowed' });
    }

    const { rows } = req.body;

    if (!rows || !Array.isArray(rows)) {
      return res.status(400).json({ error: 'Missing rows data' });
    }

    const articleNoIdx = 0;
    // Fetch IDs of ALL products that have manual edits so we don't overwrite them
    const { data: existingProducts } = await supabase
      .from('products')
      .select('product_id, status');

    // Protect ALL products that are not 'excel' status (i.e. they have manual edits or special status)
    const manuallyEditedIds = new Set(
      (existingProducts || [])
        .filter(p => p.status && p.status !== 'excel')
        .map(p => p.product_id)
    );

    // Also protect any product that has history entries — they were edited at some point.
    // If their status was accidentally reset to 'excel', this restores protection.
    const { data: historyProducts } = await supabase
      .from('products_history')
      .select('product_id');
    (historyProducts || []).forEach(h => manuallyEditedIds.add(h.product_id));

    const productsToUpsert = [];
    for (const row of rows) {
      const productId = String(row[articleNoIdx]);
      // Only add if: new product OR existing but NOT manually edited
      if (productId && productId.trim() !== '' && !manuallyEditedIds.has(productId)) {
        productsToUpsert.push({
          product_id: productId,
          data: row,
          status: 'excel',
          updated_at: new Date().toISOString()
        });
      }
    }

    console.log('Upserting', productsToUpsert.length, 'new/updated products to Supabase...');

    // We can now use a normal upsert because we filtered out the manual edits
    const { error } = await supabase
      .from('products')
      .upsert(productsToUpsert, { onConflict: 'product_id' });

    if (error) {
      console.error('Supabase upsert error:', error);
      return res.status(500).json({ error: error.message, detail: 'Failed to upsert products' });
    }

    return res.json({
      success: true,
      syncedCount: productsToUpsert.length
    });
  } catch (err) {
    console.error('Handler error:', err);
    res.status(500).json({ error: err.message });
  }
}