const { pool } = require('../db');

const normalizeText = (value) => String(value || '').replace(/\s+/g, ' ').trim();
const normalizeSku = (value) => normalizeText(value).toUpperCase();
const isRawOrService = (value) => /\b(?:MALHA|RIBANA|FIO|TECIDO|SERVICO|SERVIÇO|TINTURARIA|TECELAGEM|FRETE)\b/i.test(value);

const getDataHealthSummary = async () => {
    const [productsResult, compositionsResult, componentsResult, stockResult] = await Promise.all([
        pool.query(`
            SELECT produto_id AS id, MAX(NULLIF(produto_descricao, '')) AS name FROM orders GROUP BY produto_id
            UNION
            SELECT produto_id AS id, MAX(NULLIF(nome, '')) AS name FROM stock GROUP BY produto_id;
        `),
        pool.query(`
            SELECT id, finished_tiny_product_id, finished_product_sku, finished_product_description, finished_product_unit
            FROM product_compositions WHERE source = 'tiny_olist_v3';
        `),
        pool.query(`
            SELECT product_composition_id, component_tiny_id, component_sku, component_name, quantity_per_unit, unit
            FROM product_composition_components;
        `),
        pool.query(`SELECT produto_id, nome, COALESCE(saldo, 0)::numeric AS saldo FROM stock;`)
    ]);

    const products = Array.from(new Map(productsResult.rows.map(row => [normalizeSku(row.id), row])).values());
    const compositions = compositionsResult.rows;
    const components = componentsResult.rows;
    const stock = stockResult.rows;
    const stockKeys = new Set(stock.flatMap(item => [normalizeSku(item.produto_id), normalizeSku(item.nome)]).filter(Boolean));
    const compositionKeys = new Set(compositions.flatMap(item => [normalizeSku(item.finished_tiny_product_id), normalizeSku(item.finished_product_sku)]).filter(Boolean));
    const productKeys = new Set(products.map(item => normalizeSku(item.id)).filter(Boolean));
    const linkedComponentKeys = new Set([...stockKeys, ...productKeys]);
    const materialKeys = new Set(components.map(item => normalizeSku(item.component_tiny_id) || normalizeSku(item.component_sku) || normalizeSku(item.component_name)).filter(Boolean));
    const materialStockKeys = new Set([...materialKeys].filter(key => stockKeys.has(key)));
    const rowsByComposition = new Map(compositions.map(item => [Number(item.id), item]));
    const issues = [];
    const addIssue = (type, severity, title, detail, productSku = '', component = '') => {
        issues.push({ type, severity, title, detail, productSku, component });
    };

    compositions.filter(row => !normalizeText(row.finished_product_sku)).forEach(row => {
        addIssue('missing_product_sku', 'critical', 'Produto sem SKU', normalizeText(row.finished_product_description) || 'Composição sem descrição', '', '');
    });
    components.filter(row => {
        const key = normalizeSku(row.component_tiny_id) || normalizeSku(row.component_sku) || normalizeSku(row.component_name);
        return !key || !linkedComponentKeys.has(key);
    }).forEach(row => {
        const parent = rowsByComposition.get(Number(row.product_composition_id));
        addIssue('component_without_stock_link', 'attention', 'Componente sem vínculo de estoque', normalizeText(row.component_name) || 'Componente sem nome', normalizeText(parent?.finished_product_sku), normalizeText(row.component_sku || row.component_tiny_id));
    });
    components.filter(row => {
        const quantity = Number(row.quantity_per_unit || 0);
        return !Number.isFinite(quantity) || quantity <= 0 || quantity > 100 || !normalizeText(row.unit);
    }).forEach(row => {
        const parent = rowsByComposition.get(Number(row.product_composition_id));
        addIssue('suspicious_quantity', 'attention', 'Quantidade suspeita', `${normalizeText(row.component_name)} · ${row.quantity_per_unit || 0} ${normalizeText(row.unit) || '(sem unidade)'}`, normalizeText(parent?.finished_product_sku), normalizeText(row.component_sku || row.component_tiny_id));
    });
    compositions.filter(row => isRawOrService(row.finished_product_description) || normalizeText(row.finished_product_unit).toLowerCase() !== 'un').forEach(row => {
        addIssue('raw_or_service_structure', 'info', 'Estrutura de matéria-prima/serviço', normalizeText(row.finished_product_description), normalizeText(row.finished_product_sku), '');
    });
    products.filter(row => !compositionKeys.has(normalizeSku(row.id))).forEach(row => {
        addIssue('product_without_composition', 'attention', 'Produto sem composição', normalizeText(row.name) || normalizeText(row.id), normalizeText(row.id), '');
    });

    const productsWithComposition = products.filter(row => compositionKeys.has(normalizeSku(row.id))).length;
    const productsWithStockLink = products.filter(row => stockKeys.has(normalizeSku(row.id))).length;

    return {
        totals: {
            products: productKeys.size,
            productsWithComposition,
            productsWithStockLink,
            materials: materialKeys.size,
            materialsWithStock: materialStockKeys.size,
            compositions: compositions.length,
            components: components.length
        },
        issues: issues.sort((a, b) => {
            const severityOrder = { critical: 0, attention: 1, info: 2 };
            return severityOrder[a.severity] - severityOrder[b.severity] || a.title.localeCompare(b.title);
        })
    };
};

module.exports = { getDataHealthSummary };