trezy/next-safe

module.exports = function crunchPermissionsPolicyHeader(headerValue) {
    return Object.entries(headerValue)
        .reduce((accumulator, [key, value]) => {
            let serializedValue = value

            if (!Array.isArray(value)) {
                serializedValue = value.split(' ')
            }

            serializedValue = serializedValue.map(item => {
                // Remove unnecessary quotes from tokens
                if (item.includes('*')) {
                    return '*'
                }

                if (item === "'self'") {
                    return 'self'
                }

                // Add quotes to all items that aren't tokens
                if (!['*', 'self'].includes(item) && !/^['"].*['"]$/) {
                    return item
                        .replace(/^['"]/, '"')
                        .replace(/['"]$/, '"')
                }

                return item
            })

            accumulator.push(`${key}=(${serializedValue.join(' ')})`)

            return accumulator
        }, [])
        .join(',')
}