"use client";

import { useState } from "react";
import useSWR from "swr";
import AppShell from "@/components/AppShell";
import {
  ConfirmDialog,
  EmptyState,
  FormError,
  LoadError,
  Modal,
  PageHeader,
  SkeletonRows,
  StatusBadge,
} from "@/components/ui";
import { useToast } from "@/components/toast";
import { api, fetcher } from "@/lib/api";

type User = {
  id: number;
  email: string;
  full_name: string | null;
  role: string;
  is_active: boolean;
};

const ROLES = ["readonly", "support", "admin"];

export default function UsersPage() {
  const { data: users, error: usersError, isLoading, mutate } = useSWR<User[]>(
    "/api/users",
    fetcher
  );
  const toast = useToast();
  const [open, setOpen] = useState(false);
  const [form, setForm] = useState({ email: "", password: "", full_name: "", role: "readonly" });
  const [error, setError] = useState<string | null>(null);
  const [creating, setCreating] = useState(false);
  const [deleteId, setDeleteId] = useState<number | null>(null);
  const [deleting, setDeleting] = useState(false);

  const create = async (e: React.FormEvent) => {
    e.preventDefault();
    setError(null);
    setCreating(true);
    try {
      await api("/api/users", { method: "POST", body: JSON.stringify(form) });
      setOpen(false);
      setForm({ email: "", password: "", full_name: "", role: "readonly" });
      toast.success("User created");
      mutate();
    } catch (err: any) {
      setError(err.message);
      toast.error(err.message || "Could not create user");
    } finally {
      setCreating(false);
    }
  };

  const update = async (id: number, patch: Partial<User>) => {
    try {
      await api(`/api/users/${id}`, { method: "PATCH", body: JSON.stringify(patch) });
      toast.success("User updated");
      mutate();
    } catch (err: any) {
      toast.error(err.message || "Update failed");
    }
  };

  const remove = async () => {
    if (deleteId == null) return;
    setDeleting(true);
    try {
      await api(`/api/users/${deleteId}`, { method: "DELETE" });
      toast.success("User deleted");
      mutate();
    } catch (err: any) {
      toast.error(err.message || "Delete failed");
    } finally {
      setDeleting(false);
      setDeleteId(null);
    }
  };

  return (
    <AppShell>
      <PageHeader
        title="Users"
        subtitle="Manage operators and their roles"
        action={
          <button className="btn-primary" onClick={() => setOpen(true)}>
            + New user
          </button>
        }
      />
      {isLoading && !users ? (
        <SkeletonRows rows={4} />
      ) : usersError ? (
        <LoadError message="Couldn’t load users." onRetry={() => mutate()} />
      ) : (users || []).length === 0 ? (
        <EmptyState title="No users yet" description="Create the first operator account." />
      ) : (
        <div className="card overflow-x-auto p-0">
          <table className="w-full min-w-[640px]">
            <thead>
              <tr>
                <th className="th">Email</th>
                <th className="th">Name</th>
                <th className="th">Role</th>
                <th className="th">Active</th>
                <th className="th"></th>
              </tr>
            </thead>
            <tbody>
              {(users || []).map((u) => (
                <tr key={u.id}>
                  <td className="td">{u.email}</td>
                  <td className="td">{u.full_name || "—"}</td>
                  <td className="td">
                    <select
                      aria-label={`Role for ${u.email}`}
                      className="input max-w-[140px]"
                      value={u.role}
                      onChange={(e) => update(u.id, { role: e.target.value as any })}
                    >
                      {ROLES.map((r) => (
                        <option key={r} value={r}>
                          {r}
                        </option>
                      ))}
                    </select>
                  </td>
                  <td className="td">
                    <button
                      aria-label={`Toggle active for ${u.email}`}
                      aria-pressed={u.is_active}
                      onClick={() => update(u.id, { is_active: !u.is_active })}
                    >
                      <StatusBadge status={u.is_active ? "loaded" : "stopped"} />
                    </button>
                  </td>
                  <td className="td text-right">
                    <button className="btn-danger btn-sm" onClick={() => setDeleteId(u.id)}>
                      Delete
                    </button>
                  </td>
                </tr>
              ))}
            </tbody>
          </table>
        </div>
      )}

      <Modal open={open} onClose={() => setOpen(false)} title="Create user">
        <form onSubmit={create} className="space-y-4">
          <div>
            <label htmlFor="user-email" className="label">
              Email
            </label>
            <input
              id="user-email"
              className="input"
              type="email"
              value={form.email}
              onChange={(e) => setForm({ ...form, email: e.target.value })}
              required
            />
          </div>
          <div>
            <label htmlFor="user-name" className="label">
              Full name
            </label>
            <input
              id="user-name"
              className="input"
              value={form.full_name}
              onChange={(e) => setForm({ ...form, full_name: e.target.value })}
            />
          </div>
          <div>
            <label htmlFor="user-password" className="label">
              Password
            </label>
            <input
              id="user-password"
              className="input"
              type="password"
              value={form.password}
              onChange={(e) => setForm({ ...form, password: e.target.value })}
              required
            />
          </div>
          <div>
            <label htmlFor="user-role" className="label">
              Role
            </label>
            <select
              id="user-role"
              className="input"
              value={form.role}
              onChange={(e) => setForm({ ...form, role: e.target.value })}
            >
              {ROLES.map((r) => (
                <option key={r} value={r}>
                  {r}
                </option>
              ))}
            </select>
          </div>
          <FormError message={error} />
          <button className="btn-primary w-full" disabled={creating}>
            {creating ? "Creating…" : "Create"}
          </button>
        </form>
      </Modal>

      <ConfirmDialog
        open={deleteId != null}
        title="Delete user?"
        message="This permanently removes the user account."
        confirmLabel="Delete"
        destructive
        busy={deleting}
        onConfirm={remove}
        onCancel={() => setDeleteId(null)}
      />
    </AppShell>
  );
}