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

const PRODUCT_TYPES = new Set(['finished_product', 'raw_material']);

const normalizeText = (value) => String(value || '').replace(/\s+/g, ' ').trim();

const normalizeNumber = (value) => {
    if (value === '' || value === null || value === undefined) return null;
    const number = Number(String(value).replace(',', '.'));
    return Number.isFinite(number) && number > 0 ? number : null;
};

const normalizeProductType = (value) => {
    const normalized = normalizeText(value);
    return PRODUCT_TYPES.has(normalized) ? normalized : 'finished_product';
};

const normalizeStringArray = (value) => {
    if (!Array.isArray(value)) return [];
    return value.map(item => normalizeText(item)).filter(Boolean);
};

const normalizeNumericMap = (value) => {
    if (!value || typeof value !== 'object' || Array.isArray(value)) return {};
    return Object.entries(value).reduce((normalized, [key, rawValue]) => {
        const normalizedKey = normalizeText(key).toUpperCase();
        const number = normalizeNumber(rawValue);
        if (normalizedKey && number) normalized[normalizedKey] = number;
        return normalized;
    }, {});
};

const mapCategory = (row) => ({
    id: row.id,
    name: row.name,
    description: row.description || '',
    createdAt: row.created_at,
    updatedAt: row.updated_at
});

const mapProduct = (row) => ({
    id: row.id,
    type: row.type,
    sku: row.sku,
    name: row.name,
    categoryId: row.category_id,
    categoryName: row.category_name || '',
    composition: row.composition || '',
    notes: row.notes || '',
    gramature: row.gramature === null ? null : Number(row.gramature),
    materialYield: row.material_yield === null ? null : Number(row.material_yield),
    widthCm: row.width_cm === null ? null : Number(row.width_cm),
    color: row.color || '',
    subcategory: row.subcategory || '',
    sizes: row.sizes || [],
    createdAt: row.created_at,
    updatedAt: row.updated_at
});

const mapConsumptionReference = (row) => ({
    id: row.id,
    productId: row.product_id,
    productSku: row.product_sku,
    productName: row.product_name,
    materialProductId: row.material_product_id,
    materialSku: row.material_sku || '',
    materialName: row.material_name || '',
    color: row.color || '',
    generalYield: row.general_yield === null ? null : Number(row.general_yield),
    sizeYields: row.size_yields || {},
    sizeAreas: row.size_areas || {},
    gramature: row.gramature === null ? null : Number(row.gramature),
    efficiencyPercent: row.efficiency_percent === null ? null : Number(row.efficiency_percent),
    ribGPerPiece: row.rib_g_per_piece === null ? null : Number(row.rib_g_per_piece),
    materialCostPerKg: row.material_cost_per_kg === null ? null : Number(row.material_cost_per_kg),
    createdAt: row.created_at,
    updatedAt: row.updated_at
});

const listCategories = async () => {
    const result = await pool.query(`
        SELECT id, name, description, created_at, updated_at
        FROM catalog_categories
        ORDER BY name
    `);
    return result.rows.map(mapCategory);
};

const createCategory = async ({ name, description }) => {
    const normalizedName = normalizeText(name);
    if (!normalizedName) {
        const error = new Error('Nome da categoria é obrigatório.');
        error.statusCode = 400;
        throw error;
    }

    const result = await pool.query(`
        INSERT INTO catalog_categories (name, description, updated_at)
        VALUES ($1, $2, CURRENT_TIMESTAMP)
        ON CONFLICT (name) DO UPDATE
        SET description = EXCLUDED.description,
            updated_at = CURRENT_TIMESTAMP
        RETURNING id, name, description, created_at, updated_at
    `, [normalizedName, normalizeText(description) || null]);

    return mapCategory(result.rows[0]);
};

const deleteCategory = async (id) => {
    await pool.query('DELETE FROM catalog_categories WHERE id = $1', [id]);
};

const listProducts = async () => {
    const result = await pool.query(`
        SELECT
            p.id, p.type, p.sku, p.name, p.category_id, c.name AS category_name,
            p.composition, p.notes, p.gramature, p.material_yield, p.width_cm,
            p.color, p.subcategory, p.sizes, p.created_at, p.updated_at
        FROM catalog_products p
        LEFT JOIN catalog_categories c ON c.id = p.category_id
        ORDER BY p.type, p.name, p.sku
    `);
    return result.rows.map(mapProduct);
};

const createProduct = async (payload) => {
    const type = normalizeProductType(payload.type);
    const sku = normalizeText(payload.sku).toUpperCase();
    const name = normalizeText(payload.name);

    if (!sku || !name) {
        const error = new Error('SKU e nome do produto são obrigatórios.');
        error.statusCode = 400;
        throw error;
    }

    const categoryId = Number(payload.categoryId) || null;
    const result = await pool.query(`
        INSERT INTO catalog_products (
            type, sku, name, category_id, composition, notes, gramature,
            material_yield, width_cm, color, subcategory, sizes, updated_at
        )
        VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, CURRENT_TIMESTAMP)
        ON CONFLICT (sku) DO UPDATE
        SET type = EXCLUDED.type,
            name = EXCLUDED.name,
            category_id = EXCLUDED.category_id,
            composition = EXCLUDED.composition,
            notes = EXCLUDED.notes,
            gramature = EXCLUDED.gramature,
            material_yield = EXCLUDED.material_yield,
            width_cm = EXCLUDED.width_cm,
            color = EXCLUDED.color,
            subcategory = EXCLUDED.subcategory,
            sizes = EXCLUDED.sizes,
            updated_at = CURRENT_TIMESTAMP
        RETURNING id
    `, [
        type,
        sku,
        name,
        categoryId,
        normalizeText(payload.composition) || null,
        normalizeText(payload.notes) || null,
        normalizeNumber(payload.gramature),
        normalizeNumber(payload.materialYield),
        normalizeNumber(payload.widthCm),
        normalizeText(payload.color) || null,
        normalizeText(payload.subcategory) || null,
        normalizeStringArray(payload.sizes)
    ]);

    const products = await listProducts();
    return products.find(product => product.id === result.rows[0].id);
};

const deleteProduct = async (id) => {
    await pool.query('DELETE FROM catalog_products WHERE id = $1', [id]);
};

const listConsumptionReferences = async () => {
    const result = await pool.query(`
        SELECT
            r.id, r.product_id, p.sku AS product_sku, p.name AS product_name,
            r.material_product_id, m.sku AS material_sku, m.name AS material_name,
            r.color, r.general_yield, r.size_yields, r.size_areas,
            r.gramature, r.efficiency_percent, r.rib_g_per_piece,
            r.material_cost_per_kg, r.created_at, r.updated_at
        FROM consumption_references r
        JOIN catalog_products p ON p.id = r.product_id
        LEFT JOIN catalog_products m ON m.id = r.material_product_id
        ORDER BY p.name, m.name NULLS FIRST, r.color NULLS FIRST
    `);
    return result.rows.map(mapConsumptionReference);
};

const createConsumptionReference = async (payload) => {
    const productId = Number(payload.productId);
    if (!productId) {
        const error = new Error('Produto é obrigatório.');
        error.statusCode = 400;
        throw error;
    }

    const sizeYields = normalizeNumericMap(payload.sizeYields);
    const sizeAreas = normalizeNumericMap(payload.sizeAreas);
    const generalYield = normalizeNumber(payload.generalYield);
    const calculatedYield = Object.values(sizeYields).length
        ? Object.values(sizeYields).reduce((total, value) => total + value, 0) / Object.values(sizeYields).length
        : null;

    if (!generalYield && !calculatedYield) {
        const error = new Error('Informe o rendimento geral ou por tamanho.');
        error.statusCode = 400;
        throw error;
    }

    const result = await pool.query(`
        INSERT INTO consumption_references (
            product_id, material_product_id, color, general_yield, size_yields,
            size_areas, gramature, efficiency_percent, rib_g_per_piece,
            material_cost_per_kg, updated_at
        )
        VALUES ($1, $2, $3, $4, $5::jsonb, $6::jsonb, $7, $8, $9, $10, CURRENT_TIMESTAMP)
        RETURNING id
    `, [
        productId,
        Number(payload.materialProductId) || null,
        normalizeText(payload.color) || null,
        generalYield || calculatedYield,
        JSON.stringify(sizeYields),
        JSON.stringify(sizeAreas),
        normalizeNumber(payload.gramature),
        normalizeNumber(payload.efficiencyPercent),
        normalizeNumber(payload.ribGPerPiece),
        normalizeNumber(payload.materialCostPerKg)
    ]);

    const references = await listConsumptionReferences();
    return references.find(reference => reference.id === result.rows[0].id);
};

const deleteConsumptionReference = async (id) => {
    await pool.query('DELETE FROM consumption_references WHERE id = $1', [id]);
};

const getCatalogSummary = async () => {
    const [categories, products, consumptionReferences] = await Promise.all([
        listCategories(),
        listProducts(),
        listConsumptionReferences()
    ]);

    return { categories, products, consumptionReferences };
};

module.exports = {
    createCategory,
    createConsumptionReference,
    createProduct,
    deleteCategory,
    deleteConsumptionReference,
    deleteProduct,
    getCatalogSummary,
    listCategories,
    listConsumptionReferences,
    listProducts
};