munch-ease-frontend/src/components/shopping/shopping.js

import units from '@/units.js';

export function mealToShoppingListSources(meal) {
    const sources = [];
    for (const recipe of meal.recipes) {
        for (const ingredient of recipe.ingredients) {
            sources.push({ ingredient, meal, recipe, });
        }
    }

    for (const ingredient of meal.extra_ingredients) {
        sources.push({ ingredient, meal, });
    }

    return sources;
}

export function requestsToSources(requests) {
    const sources = [];
    for (const request of requests) {
        if (request.ingredient) {
            sources.push(request);
        }
        else if (request.meal) {
            sources.push(...mealToShoppingListSources(request.meal));
        }
    }

    return sources;
}

export function removeMealFromShoppingListSources(sources, meal) {
    return sources.filter(source => source.meal?.id !== meal.id);
}

export function groupingToIngredients(grouping) {
    const product = grouping.product;
    const totals = [];
    for (const total of grouping.totals) {
        totals.push({ id: 0, line: `${total.quantity} ${total.unit} of ${product.name}`, preparation: '', name: product.name, product, ...total });
    }
    return totals;
}

function calculateTotals(sources) {
    const totals = {};
    for (const source of sources) {
        const { unit, factor } = units.getConversionFactor(source.ingredient.unit) ?? { unit: source.ingredient.unit, factor: 1 };

        const quantity = source.ingredient.quantity / factor;
        if (!totals[unit]) {
            totals[unit] = quantity;
        }
        else {
            totals[unit] += quantity;
        }
    }

    const result = [];
    for (const unit in totals) {
        result.push({ unit, quantity: totals[unit] });
    }

    return result;
}

export function groupByProduct(sources) {
    const noProductKey = "no-product";
    const noProduct = { name: "No product", };

    const grouped = {};
    for (const source of sources) {
        const key = source.ingredient?.product?.id ?? noProductKey;
        if (!key) {
            continue;
        }

        if (!grouped[key]) {
            grouped[key] = {
                product: source.ingredient.product ?? noProduct,
                sources: [],
            };
        }

        grouped[key].sources.push(source);
    }

    for (const key in grouped) {
        grouped[key].totals = calculateTotals(grouped[key].sources);
    }

    return Object.values(grouped);
}