export const HANDOFF_LABELS = ["Important", "Finance", "Clients", "Projects", "Personal", "Support"];

export const EMAIL_TYPE_OPTIONS = [
  {
    id: "utility",
    title: "Utility",
    description: "Account updates, alerts and service information",
  },
  {
    id: "transactional",
    title: "Transactional",
    description: "Orders, payments, invoices, receipts and account activity",
  },
  {
    id: "promotional",
    title: "Promotional",
    description: "Offers, deals and promotional messages",
  },
  {
    id: "marketing",
    title: "Marketing",
    description: "Campaigns, newsletters and marketing outreach",
  },
];

export const INSTRUCTION_EXAMPLES = [
  "Refund requests",
  "Human requested",
  "Approval needed",
];

function joinOrNone(items, fallback = "any email") {
  if (!items?.length) return fallback;
  if (items.length === 1) return items[0];
  if (items.length === 2) return `${items[0]} or ${items[1]}`;
  return `${items.slice(0, -1).join(", ")} or ${items.at(-1)}`;
}

function typeTitles(types) {
  return types.map((id) => EMAIL_TYPE_OPTIONS.find((item) => item.id === id)?.title || id);
}

export function buildHandoffSummary({
  ownerEmail,
  labels,
  emailTypes,
  instructions,
}) {
  const labelText = labels?.length
    ? `${joinOrNone(labels)} emails`
    : "eligible emails";
  const typeText = emailTypes?.length
    ? typeTitles(emailTypes).join(" or ").toLowerCase()
    : "any type";
  const instructionText = instructions?.trim()
    ? "when they require your personal decision or attention"
    : "when your handoff instructions apply";

  return `Your agent will handle email normally. ${labelText} that are ${typeText} will be handed to ${ownerEmail || "the human owner"} ${instructionText}.`;
}

export function buildRuleCardSummary(rule) {
  const parts = [];
  if (rule.labels?.length) parts.push(rule.labels.join(", "));
  if (rule.email_types?.length) {
    parts.push(typeTitles(rule.email_types).join(", "));
  }
  const meta = parts.length ? parts.join(" • ") : "All eligible emails";
  const replies = rule.allow_replies ? "Replies enabled" : "View only";
  return `${meta} • ${replies}`;
}