const ProductService =
require("../services/ProductService");

const CategoryService = require("../services/CategoryService");

const parseCsv = require("../utils/parseCsv");

class ProductController {


    index(req, res) {

        const products =
        ProductService.getProducts(req.user.household_id);

        const categories = CategoryService.getCategories(req.user.household_id);

        res.render(
            "products/index",
            {
                title:"Producten",
                products,
                categories
            }

        );

    }

    create(req, res) {
        const name = (req.body.name || "").trim();
        const categoryId = req.body.category_id
            ? Number.parseInt(req.body.category_id, 10)
            : null;

        if (!name || (categoryId !== null && !Number.isInteger(categoryId))) {
            req.flash("error", "Geef een geldige productnaam en categorie op.");
            return res.redirect("/products");
        }

        if (categoryId !== null && !CategoryService.getCategory(categoryId, req.user.household_id)) {
            req.flash("error", "De gekozen categorie bestaat niet.");
            return res.redirect("/products");
        }

        ProductService.createProduct({
            name,
            category_id: categoryId,
            household_id: req.user.household_id
        });

        req.flash("success", "Product toegevoegd.");
        res.redirect("/products");
    }


    import(req, res) {
        if (!req.file) {
            req.flash("error", "Kies eerst een CSV-bestand.");
            return res.redirect("/products");
        }

        let rows;
        try {
            rows = parseCsv(req.file.buffer.toString("utf8").replace(/^\uFEFF/, ""));
        } catch (error) {
            req.flash("error", `CSV kan niet worden gelezen: ${error.message}`);
            return res.redirect("/products");
        }

        if (rows.length < 2) {
            req.flash("error", "Het CSV-bestand bevat geen producten.");
            return res.redirect("/products");
        }

        const headers = rows[0].map(header => header.trim().toLowerCase());
        const nameIndex = headers.indexOf("name");
        const categoryIndex = headers.includes("category")
            ? headers.indexOf("category")
            : headers.indexOf("category_name");
        const barcodeIndex = headers.indexOf("barcode");

        if (nameIndex === -1) {
            req.flash("error", "De CSV moet een kolom 'name' bevatten.");
            return res.redirect("/products");
        }

        const categories = CategoryService.getCategories(req.user.household_id);
        const categoryIds = new Map(
            categories.map(category => [category.name.trim().toLowerCase(), category.id])
        );
        const products = [];
        const errors = [];

        rows.slice(1).forEach((row, rowIndex) => {
            const lineNumber = rowIndex + 2;
            const name = (row[nameIndex] || "").trim();
            const categoryName = categoryIndex === -1
                ? ""
                : (row[categoryIndex] || "").trim();
            const categoryId = categoryName
                ? categoryIds.get(categoryName.toLowerCase())
                : null;

            if (!name) errors.push(`regel ${lineNumber}: productnaam ontbreekt`);
            if (categoryName && !categoryId) {
                errors.push(`regel ${lineNumber}: categorie '${categoryName}' bestaat niet`);
            }

            products.push({
                name,
                category_id: categoryId,
                barcode: barcodeIndex === -1 ? "" : (row[barcodeIndex] || "").trim(),
                household_id: req.user.household_id
            });
        });

        if (errors.length > 0) {
            req.flash("error", `Import afgebroken: ${errors.slice(0, 5).join("; ")}`);
            return res.redirect("/products");
        }

        ProductService.createProducts(products);
        req.flash("success", `${products.length} producten geïmporteerd.`);
        res.redirect("/products");
    }


    editForm(req, res) {
        const productId = Number.parseInt(req.params.id, 10);
        const product = Number.isInteger(productId)
            ? ProductService.getProduct(productId, req.user.household_id)
            : null;

        if (!product) {
            req.flash("error", "Product niet gevonden.");
            return res.redirect("/products");
        }

        const categories = CategoryService.getCategories(req.user.household_id);

        res.render("products/edit", {
            title: "Product wijzigen",
            product,
            categories
        });
    }


    update(req, res) {
        const productId = Number.parseInt(req.params.id, 10);
        const name = (req.body.name || "").trim();
        const categoryId = req.body.category_id
            ? Number.parseInt(req.body.category_id, 10)
            : null;

        if (!Number.isInteger(productId) || !name ||
            (categoryId !== null && !Number.isInteger(categoryId))) {
            req.flash("error", "Geef een geldige productnaam en categorie op.");
            return res.redirect("/products");
        }

        if (categoryId !== null && !CategoryService.getCategory(categoryId, req.user.household_id)) {
            req.flash("error", "De gekozen categorie bestaat niet.");
            return res.redirect(`/products/${productId}/edit`);
        }

        const result = ProductService.updateProduct(productId, req.user.household_id, {
            name,
            category_id: categoryId
        });

        if (result.changes === 0) {
            req.flash("error", "Product niet gevonden.");
            return res.redirect("/products");
        }

        req.flash("success", "Product gewijzigd.");
        res.redirect("/products");
    }


    remove(req, res) {
        const productId = Number.parseInt(req.params.id, 10);

        if (!Number.isInteger(productId)) {
            req.flash("error", "Product niet gevonden.");
            return res.redirect("/products");
        }

        if (ProductService.productHasListItems(productId, req.user.household_id)) {
            req.flash(
                "error",
                "Dit product staat nog op een boodschappenlijst en kan niet worden verwijderd."
            );
            return res.redirect(`/products/${productId}/edit`);
        }

        const result = ProductService.deleteProduct(productId, req.user.household_id);

        if (result.changes === 0) {
            req.flash("error", "Product niet gevonden.");
            return res.redirect("/products");
        }

        req.flash("success", "Product verwijderd.");
        res.redirect("/products");
    }



}


module.exports =
new ProductController();