import { auth } from "@/auth";
import { db } from "@/lib/db";
import { hasPermission } from "@/lib/permissions";
import { CREWING_ENABLED } from "@/lib/feature-flags";
import { redirect, notFound } from "next/navigation";
import Link from "next/link";
import { ArrowLeft } from "lucide-react";
import { Badge } from "@/components/ui/badge";
import { SOURCE_LABEL, STATUS_LABEL, STATUS_VARIANT, experienceLabel } from "../candidate-ui";
import type { Metadata } from "next";

export const metadata: Metadata = { title: "Candidate" };

export default async function CandidateDetailPage({ params }: { params: Promise<{ id: string }> }) {
  if (!CREWING_ENABLED) notFound();

  const session = await auth();
  if (!session?.user) redirect("/login");
  if (!hasPermission(session.user.role, "manage_candidates")) redirect("/dashboard");

  const { id } = await params;
  const c = await db.crewMember.findUnique({
    where: { id },
    include: {
      appliedRank: { select: { name: true } },
      currentRank: { select: { name: true } },
      // B3 AC3 — pull the returning hand's history so the callout shows real records.
      experienceRecords: { orderBy: { fromDate: "desc" }, include: { rank: { select: { name: true } } } },
      documents: { orderBy: { createdAt: "desc" }, select: { id: true, docType: true, expiryDate: true } },
    },
  });
  if (!c) notFound();

  const profile: [string, string][] = [
    ["Rank applied", c.appliedRank?.name ?? "—"],
    ["Last rank held", c.currentRank?.name ?? "—"],
    ["Experience", experienceLabel(c.experienceMonths)],
    ["Vessel type", c.vesselTypeExperience ?? "—"],
    ["Source", SOURCE_LABEL[c.source]],
    ["Email", c.email ?? "—"],
    ["Phone", c.phone ?? "—"],
  ];

  return (
    <div className="max-w-4xl">
      <Link href="/crewing/candidates" className="inline-flex items-center gap-1.5 text-sm text-neutral-500 hover:text-neutral-800 mb-4">
        <ArrowLeft className="h-4 w-4" /> Candidates
      </Link>

      <div className="mb-6 flex items-start justify-between">
        <div className="flex items-center gap-3">
          <h1 className="text-2xl font-semibold text-neutral-900">{c.name}</h1>
          <Badge variant={STATUS_VARIANT[c.status]}>{STATUS_LABEL[c.status]}</Badge>
          {c.source === "EX_HAND" && (
            <span className="rounded-full bg-purple-100 text-purple-700 px-2.5 py-0.5 text-xs font-medium">Returning crew</span>
          )}
        </div>
      </div>

      {c.source === "EX_HAND" && (
        <div className="mb-6 rounded-lg border border-purple-200 bg-purple-50 px-4 py-3 text-sm text-purple-800">
          <strong>Returning crew.</strong> The interview may be waived with Manager approval.{" "}
          {c.experienceRecords.length === 0 && c.documents.length === 0 ? (
            <span>No prior records are on file yet.</span>
          ) : (
            <span>Prior records on file from earlier assignments:</span>
          )}

          {c.experienceRecords.length > 0 && (
            <div className="mt-3">
              <p className="text-xs font-semibold uppercase tracking-wide text-purple-600 mb-1">Tour history</p>
              <ul className="space-y-1">
                {c.experienceRecords.map((e) => (
                  <li key={e.id} className="text-sm text-purple-900">
                    {e.rank?.name ?? "—"}
                    {e.vesselType ? ` · ${e.vesselType}` : ""}
                    {e.durationMonths != null ? ` · ${experienceLabel(e.durationMonths)}` : ""}
                    {e.fromDate ? ` (${e.fromDate.getFullYear()}${e.toDate ? `–${e.toDate.getFullYear()}` : ""})` : ""}
                  </li>
                ))}
              </ul>
            </div>
          )}

          {c.documents.length > 0 && (
            <div className="mt-3">
              <p className="text-xs font-semibold uppercase tracking-wide text-purple-600 mb-1">Documents on file</p>
              <div className="flex flex-wrap gap-1.5">
                {c.documents.map((doc) => (
                  <span key={doc.id} className="rounded bg-purple-100 px-2 py-0.5 text-xs text-purple-800">
                    {doc.docType}
                    {doc.expiryDate ? ` · exp ${doc.expiryDate.getFullYear()}` : ""}
                  </span>
                ))}
              </div>
            </div>
          )}
        </div>
      )}

      <div className="grid grid-cols-1 lg:grid-cols-2 gap-6">
        {/* Profile */}
        <div className="rounded-lg border border-neutral-200 bg-white overflow-hidden">
          <div className="px-4 py-3 border-b border-neutral-200 bg-neutral-50">
            <h2 className="text-sm font-semibold text-neutral-900">Profile</h2>
          </div>
          <dl className="divide-y divide-neutral-100">
            {profile.map(([k, v]) => (
              <div key={k} className="flex justify-between gap-4 px-4 py-2.5">
                <dt className="text-sm text-neutral-500">{k}</dt>
                <dd className="text-sm text-neutral-900 text-right">{v}</dd>
              </div>
            ))}
          </dl>
          {c.notes && (
            <div className="px-4 py-3 border-t border-neutral-100">
              <p className="text-xs font-medium text-neutral-500 mb-1">Notes</p>
              <p className="text-sm text-neutral-700">{c.notes}</p>
            </div>
          )}
        </div>

        {/* Recruitment pipeline — Phase 3b */}
        <div className="rounded-lg border border-neutral-200 bg-white overflow-hidden">
          <div className="px-4 py-3 border-b border-neutral-200 bg-neutral-50">
            <h2 className="text-sm font-semibold text-neutral-900">Recruitment</h2>
          </div>
          <p className="px-4 py-12 text-center text-sm text-neutral-400">
            The 7-stage recruitment pipeline (shortlist → competency &amp; references → docs →
            salary → proposed → interview → selected) arrives in the next phase. Applications
            against requisitions will appear here.
          </p>
        </div>
      </div>
    </div>
  );
}