import { permissions } from "@mrp/shared";
import type { PurchaseOrderStatus, PurchaseOrderSummaryDto } from "@mrp/shared";
import { useEffect, useState } from "react";
import { Link } from "react-router-dom";

import { useAuth } from "../../auth/AuthProvider";
import { api, ApiError } from "../../lib/api";
import { purchaseStatusFilters } from "./config";
import { PurchaseStatusBadge } from "./PurchaseStatusBadge";

export function PurchaseListPage() {
  const { token, user } = useAuth();
  const [documents, setDocuments] = useState<PurchaseOrderSummaryDto[]>([]);
  const [searchTerm, setSearchTerm] = useState("");
  const [statusFilter, setStatusFilter] = useState<"ALL" | PurchaseOrderStatus>("ALL");
  const [status, setStatus] = useState("Loading purchase orders...");

  const canManage = user?.permissions.includes("purchasing.write") ?? false;

  useEffect(() => {
    if (!token) {
      return;
    }

    api.getPurchaseOrders(token, { q: searchTerm.trim() || undefined, status: statusFilter === "ALL" ? undefined : statusFilter })
      .then((nextDocuments) => {
        setDocuments(nextDocuments);
        setStatus(`${nextDocuments.length} purchase orders matched the current filters.`);
      })
      .catch((error: unknown) => {
        const message = error instanceof ApiError ? error.message : "Unable to load purchase orders.";
        setStatus(message);
      });
  }, [searchTerm, statusFilter, token]);

  return (
    <section className="surface-panel">
      <div className="flex flex-col gap-3 lg:flex-row lg:items-start lg:justify-between">
        <div>
          <p className="section-kicker">PURCHASING</p>
          <h3 className="module-title">PURCHASE ORDERS</h3>
        </div>
        {canManage ? (
          <Link to="/purchasing/orders/new" className="inline-flex items-center justify-center rounded-2xl bg-brand px-3 py-2 text-sm font-semibold text-white">
            New purchase order
          </Link>
        ) : null}
      </div>
      <div className="mt-4 grid gap-2.5 rounded-[16px] border border-line/70 bg-page/60 p-2.5 xl:grid-cols-[1.35fr_0.8fr]">
        <label className="block">
          <span className="mb-2 block text-xs font-semibold uppercase tracking-[0.16em] text-muted">Search</span>
          <input value={searchTerm} onChange={(event) => setSearchTerm(event.target.value)} placeholder="Search purchase orders by document number or vendor" className="w-full rounded-2xl border border-line/70 bg-surface px-2 py-2 text-text outline-none transition focus:border-brand" />
        </label>
        <label className="block">
          <span className="mb-2 block text-xs font-semibold uppercase tracking-[0.16em] text-muted">Status</span>
          <select value={statusFilter} onChange={(event) => setStatusFilter(event.target.value as "ALL" | PurchaseOrderStatus)} className="w-full rounded-2xl border border-line/70 bg-surface px-2 py-2 text-text outline-none transition focus:border-brand">
            {purchaseStatusFilters.map((option) => (
              <option key={option.value} value={option.value}>
                {option.label}
              </option>
            ))}
          </select>
        </label>
      </div>
      <div className="mt-4 rounded-[16px] border border-line/70 bg-page/60 px-3 py-2 text-sm text-muted">{status}</div>
      {documents.length === 0 ? (
        <div className="mt-4 rounded-[16px] border border-dashed border-line/70 bg-page/60 px-4 py-7 text-center text-sm text-muted">No purchase orders have been added yet.</div>
      ) : (
        <div className="mt-4 overflow-hidden rounded-[16px] border border-line/70">
          <table className="min-w-full divide-y divide-line/70 text-sm">
            <thead className="bg-page/80 text-left text-muted">
              <tr>
                <th className="px-2 py-2">Document</th>
                <th className="px-2 py-2">Vendor</th>
                <th className="px-2 py-2">Status</th>
                <th className="px-2 py-2">Issue Date</th>
                <th className="px-2 py-2">Value</th>
                <th className="px-2 py-2">Lines</th>
              </tr>
            </thead>
            <tbody className="divide-y divide-line/70 bg-surface">
              {documents.map((document) => (
                <tr key={document.id} className="transition hover:bg-page/70">
                  <td className="px-2 py-2"><Link to={`/purchasing/orders/${document.id}`} className="font-semibold text-text hover:text-brand">{document.documentNumber}</Link></td>
                  <td className="px-2 py-2 text-muted">{document.vendorName}</td>
                  <td className="px-2 py-2"><PurchaseStatusBadge status={document.status} /></td>
                  <td className="px-2 py-2 text-muted">{new Date(document.issueDate).toLocaleDateString()}</td>
                  <td className="px-2 py-2 text-muted">${document.total.toFixed(2)}</td>
                  <td className="px-2 py-2 text-muted">{document.lineCount}</td>
                </tr>
              ))}
            </tbody>
          </table>
        </div>
      )}
    </section>
  );
}