import type { ApprovalRequest, ApprovalStatus } from "@/types/appops";

export interface ApprovalFollowupLink {
  label: string;
  href: string;
}

export interface ApprovalFollowupView {
  status: ApprovalStatus;
  statusLabel: string;
  expiryLabel: string;
  auditReference: string | null;
  jobReference: string | null;
  executionCopy: string;
  canDecide: boolean;
  links: ApprovalFollowupLink[];
}

export interface ApprovalEmptyState {
  title: string;
  message: string;
  actions: ApprovalFollowupLink[];
}

const statusLabels: Record<ApprovalStatus, string> = {
  pending: "Pending",
  approved: "Approved",
  rejected: "Rejected",
  expired: "Expired",
  executed: "Executed",
};

const normalizeStatus = (status?: string): ApprovalStatus => (
  status === "approved" ||
  status === "rejected" ||
  status === "expired" ||
  status === "executed"
    ? status
    : "pending"
);

const formatRelativeExpiry = (expiresAt?: string, now = new Date()): { label: string; expired: boolean } => {
  if (!expiresAt) return { label: "Geen vervaldatum", expired: false };
  const timestamp = Date.parse(expiresAt);
  if (!Number.isFinite(timestamp)) return { label: "Vervaldatum onbekend", expired: false };
  const diffMs = timestamp - now.getTime();
  const absMinutes = Math.max(1, Math.round(Math.abs(diffMs) / 60_000));
  const hours = Math.floor(absMinutes / 60);
  const minutes = absMinutes % 60;
  const duration = hours > 0 ? `${hours}u ${minutes}m` : `${absMinutes}m`;
  return diffMs < 0
    ? { label: `Verlopen ${duration} geleden`, expired: true }
    : { label: `Verloopt over ${duration}`, expired: false };
};

export const buildApprovalFollowupView = (approval: ApprovalRequest, now = new Date()): ApprovalFollowupView => {
  const status = normalizeStatus(approval.status);
  const expiry = formatRelativeExpiry(approval.expiresAt, now);
  const effectiveStatus: ApprovalStatus = status === "pending" && expiry.expired ? "expired" : status;
  const auditReference = approval.auditId || null;
  const jobReference = approval.jobId || null;
  const decided = effectiveStatus !== "pending";
  const canDecide = effectiveStatus === "pending";

  const links: ApprovalFollowupLink[] = decided
    ? [
        { label: "Open Audit", href: auditReference ? `/audit?query=${encodeURIComponent(auditReference)}` : "/audit" },
        { label: "Jobs", href: jobReference ? `/jobs?query=${encodeURIComponent(jobReference)}` : "/jobs" },
      ]
    : [
        { label: "Open Audit", href: "/audit" },
        { label: "Command Center", href: "/command-center" },
        { label: "Jobs", href: "/jobs" },
      ];

  return {
    status: effectiveStatus,
    statusLabel: statusLabels[effectiveStatus],
    expiryLabel: effectiveStatus === "expired" ? expiry.label : expiry.label,
    auditReference,
    jobReference,
    executionCopy: decided
      ? effectiveStatus === "expired"
        ? "Approval is verlopen. Er wordt geen actie uitgevoerd; maak indien nodig een nieuwe expliciete aanvraag."
        : "Beslissing opgeslagen. Controleer Audit en Jobs voor echte vervolgstatussen wanneer die beschikbaar zijn."
      : "Nog niet uitgevoerd. Goedkeuren of afwijzen schrijft audit en kan daarna een job opleveren als de actie een executor heeft.",
    canDecide,
    links,
  };
};

export const filterApprovals = (approvals: ApprovalRequest[], query: string): ApprovalRequest[] => {
  const normalizedQuery = query.trim().toLowerCase();
  if (!normalizedQuery) return approvals;

  return approvals.filter((approval) => [
    approval.id,
    approval.action,
    approval.target,
    approval.requester,
    approval.context,
    approval.reason || "",
    approval.auditId || "",
    approval.jobId || "",
  ].some((value) => value.toLowerCase().includes(normalizedQuery)));
};

export const buildApprovalEmptyState = (
  options: { totalApprovals: number; visibleApprovals: number; query: string },
): ApprovalEmptyState => {
  const query = options.query.trim();

  if (options.totalApprovals === 0) {
    return {
      title: "Geen openstaande approvals",
      message: "Er staan geen approvals klaar. Nieuwe approval-first acties verschijnen hier zodra Command Center, connectors of remediation flows er een aanvragen.",
      actions: [{ label: "Command Center", href: "/command-center" }],
    };
  }

  if (query && options.visibleApprovals === 0) {
    return {
      title: "Geen approval voor deze handoff",
      message: `Er is geen approval gevonden voor "${query}". Controleer Audit of Jobs om te zien of de aanvraag al verwerkt, verlopen of als job doorgezet is.`,
      actions: [
        { label: "Toon alle approvals", href: "/approvals" },
        { label: "Zoek in Audit", href: `/audit?query=${encodeURIComponent(query)}` },
        { label: "Zoek in Jobs", href: `/jobs?query=${encodeURIComponent(query)}` },
        { label: "Command Center", href: "/command-center" },
      ],
    };
  }

  return {
    title: "Geen approvals zichtbaar",
    message: "De huidige selectie bevat geen approvals. Toon alles of start een nieuwe approval-first actie via Command Center.",
    actions: [
      { label: "Toon alle approvals", href: "/approvals" },
      { label: "Command Center", href: "/command-center" },
    ],
  };
};