/**
 * Copy text to the clipboard with a fallback for non-secure contexts.
 *
 * `navigator.clipboard` is only available in secure contexts (HTTPS or
 * localhost). On a plain HTTP origin (e.g. an internal/prod server without
 * TLS) the API is missing, so we fall back to the legacy
 * `document.execCommand('copy')` using a temporary off-screen textarea.
 *
 * @returns `true` if the copy succeeded, `false` otherwise.
 */
export async function copyToClipboard(text: string): Promise<boolean> {
    // Preferred path: available in secure contexts (HTTPS / localhost).
    if (navigator.clipboard && window.isSecureContext) {
        try {
            await navigator.clipboard.writeText(text)
            return true
        } catch {
            // Fall through to the legacy fallback below.
        }
    }

    // Legacy fallback: works on plain HTTP origins.
    try {
        const textarea = document.createElement('textarea')
        textarea.value = text
        // Keep it out of view and prevent layout shift / scrolling.
        textarea.style.position = 'fixed'
        textarea.style.top = '-9999px'
        textarea.style.left = '-9999px'
        textarea.setAttribute('readonly', '')
        document.body.appendChild(textarea)
        textarea.select()
        textarea.setSelectionRange(0, text.length)
        const ok = document.execCommand('copy')
        document.body.removeChild(textarea)
        return ok
    } catch {
        return false
    }
}