// pages/api/magento-product.ts
import type { NextApiRequest, NextApiResponse } from 'next';

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse
) {
  // Kita terima 'skus' (banyak) dan 'main_sku' (utama/pertama)
  const { skus, main_sku } = req.query;

  if (!skus) {
    return res.status(400).json({ error: 'SKUs are required' });
  }

  const token = process.env.MAGENTO_API_KEY || '';
  const baseUrl = process.env.MAGENTO_API_HOST || '';

  try {
    const skuList = String(skus).split(','); // Contoh: ['221', '222', '223']
    const mainSku = String(main_sku || skuList[0]).trim(); // Fallback ke yang pertama

    // =====================================================================
    // 1. FETCH SEMUA VARIAN SEKALIGUS (Optimasi 'IN' Operator)
    // =====================================================================
    const searchParams = new URLSearchParams({
        'searchCriteria[filter_groups][0][filters][0][field]': 'sku',
        'searchCriteria[filter_groups][0][filters][0][value]': skuList.join(','),
        'searchCriteria[filter_groups][0][filters][0][condition_type]': 'in'
    });

    const productUrl = `${baseUrl}/products?${searchParams.toString()}`;
    
    const productResponse = await fetch(productUrl, {
      method: 'GET',
      headers: {
        'Content-Type': 'application/json',
        'Authorization': `Bearer ${token}`,
      },
    });

    if (!productResponse.ok) {
        return res.status(200).json({ specsMatrix: [], upsell_ids: [], related_ids: [] });
    }

    const productData = await productResponse.json();
    const items = productData.items || [];

    if (items.length === 0) {
        return res.status(200).json({ specsMatrix: [], upsell_ids: [], related_ids: [] });
    }

    const cleanAttributeValue = (val: any) => {
        if (val === null || val === undefined) return '';
        let str = String(val).trim();
        if (str.length >= 2 && str.startsWith('"') && str.endsWith('"')) {
            str = str.slice(1, -1).trim();
        }
        return str;
    };

    // =====================================================================
    // 2. BUILD SPECS MATRIX
    // =====================================================================
    
    // Kumpulkan semua kode atribut unik
    const allAttributeCodes = new Set<string>();
    items.forEach((p: any) => {
        if (p.custom_attributes) {
            p.custom_attributes.forEach((attr: any) => {
                if (attr.attribute_code.startsWith('z')) {
                    allAttributeCodes.add(attr.attribute_code);
                }
            });
        }
    });

    // Fetch Label untuk atribut-atribut tersebut (Sekali jalan)
    const labelsMap: Record<string, string> = {};
    await Promise.all(Array.from(allAttributeCodes).map(async (code) => {
        try {
            const attrUrl = `${baseUrl}/products/attributes/${code}`;
            const res = await fetch(attrUrl, { headers: { 'Authorization': `Bearer ${token}` } });
            if (res.ok) {
                const json = await res.json();
                labelsMap[code] = json.default_frontend_label || code;
            }
        } catch (e) {}
        
        // Fallback label jika gagal
        if (!labelsMap[code]) {
            labelsMap[code] = code.substring(1).replace(/_/g, ' ').trim();
        }
    }));

    // Susun Matrix
    // Struktur: { code, label, values: { [sku]: value } }
    const matrix: any[] = [];
    
    Array.from(allAttributeCodes).forEach((code) => {
        const row: any = {
            code: code,
            label: labelsMap[code],
            values: {} 
        };

        let hasData = false;

        items.forEach((p: any) => {
            const attr = p.custom_attributes.find((a: any) => a.attribute_code === code);
            // Gunakan helper cleanAttributeValue disini
            const rawVal = attr ? cleanAttributeValue(attr.value) : '';
            
            if (rawVal !== '' && rawVal !== '-') {
                hasData = true;
            } 
            row.values[p.sku] = rawVal; 
        });

        if (hasData) {
            matrix.push(row);
        }
    });

    // Deskripsi produk per varian
    const descriptions:Record<string, string> = {};
    items.forEach((p: any) => {
        const descAttr = p.custom_attributes.find((a: any) => a.attribute_code === 'description' || a.attribute_code === 'short_description');
        descriptions[p.sku] = descAttr ? descAttr.value : '';
    });
    
    const warranties: Record<string, string> = {};
    items.forEach((p: any) => {
        const warAttr = p.custom_attributes.find((a: any) => a.attribute_code === 'z_warranty');
        warranties[p.sku] = warAttr ? cleanAttributeValue(warAttr.value) : '';
    });

    // =====================================================================
    // 3. AMBIL LINKS (UPSELL & RELATED) DARI MAIN VARIANT SAJA
    // =====================================================================
    const mainProduct = items.find((p: any) => String(p.sku) === mainSku) || items[0];

    let upsellIds: number[] = [];
    let relatedIds: number[] = [];

    if (mainProduct && mainProduct.product_links) {
        mainProduct.product_links.forEach((link: any) => {
            if (link.link_type === 'upsell') {
                upsellIds.push(Number(link.linked_product_sku));
            } else if (link.link_type === 'related') {
                relatedIds.push(Number(link.linked_product_sku));
            }
        });
    }

    // Response
    res.status(200).json({
        specsMatrix: matrix,
        upsell_ids: upsellIds,
        related_ids: relatedIds,
        descriptions: descriptions,
        warranties: warranties,
    });

  } catch (error) {
    console.error('Proxy Error:', error);
    res.status(500).json({ error: 'Internal Server Error' });
  }
}