BEM deps to import

depsToImport.js

function depsToImport(deps) {
    const uniq = a => [...new Set(a)];
    return Object.values(
        deps
            .map(({ block, ...rest }) => ({ block: Array.isArray(block) ? block[0] : block, ...rest }))
            .reduce((res, { block, elem, mod, val }) => {
                const key = elem ? `${block}__${elem}` : block;
                const cur = res[key] || {};
                return {
                    ...res,
                    [key]: {
                        ...cur,
                        block,
                        ...(elem && { elem }),
                        ...(mod && {
                            mod: {
                                ...cur.mod,
                                ...(val && {
                                    [mod]: uniq([...((cur.mod && cur.mod[mod]) ? cur.mod[mod] : []), val]),
                                })
                            },
                        })
                    },
                };
            }, {})
    ).map(({ block, elem, mod }) => {
        const res = [`b:${block}`];
        if (elem) {
            res.push(`e:${elem}`);
        }
        if (mod && Object.keys(mod).length) {
            res.push(
                Object
                    .entries(mod)
                    .map(
                        ([key, values]) =>
                            ((values.length === 1 && values[0] === true) ? `m:${key}` : `m:${key}=${values.join('|')}`)
                    )
                    .join(' ')
            );
        }
        return `import '${res.join(' ')}';`;
    }).sort().join('\n');
}