import React from "react";
import { NavLink, Navigate, Route, Routes, useLocation, useNavigate } from "react-router-dom";
import { useAuth } from "./state";
import { LoginPage } from "./pages/LoginPage";
import { DashboardPage } from "./pages/DashboardPage";
import { TargetsPage } from "./pages/TargetsPage";
import { TargetDetailPage } from "./pages/TargetDetailPage";
import { QueryInsightsPage } from "./pages/QueryInsightsPage";
import { AlertsPage } from "./pages/AlertsPage";
import { AdminUsersPage } from "./pages/AdminUsersPage";

function Protected({ children }) {
  const { tokens } = useAuth();
  const location = useLocation();
  if (!tokens?.accessToken) return <Navigate to="/login" state={{ from: location.pathname }} replace />;
  return children;
}

function Layout({ children }) {
  const { me, logout, uiMode, setUiMode, alertToasts, dismissAlertToast } = useAuth();
  const navigate = useNavigate();
  const navClass = ({ isActive }) => `nav-btn${isActive ? " active" : ""}`;

  return (
    <div className="shell">
      <aside className="sidebar">
        <div className="brand">
          <img src="/nexapg-logo.svg" alt="NexaPG" className="brand-logo" />
          <h1>NexaPG</h1>
        </div>
        <nav className="sidebar-nav">
          <NavLink to="/" end className={navClass}>
            <span className="nav-icon" aria-hidden="true">
              <svg viewBox="0 0 24 24">
                <path d="M4 6c0-1.7 3.6-3 8-3s8 1.3 8 3-3.6 3-8 3-8-1.3-8-3zm0 6c0 1.7 3.6 3 8 3s8-1.3 8-3M4 18c0 1.7 3.6 3 8 3s8-1.3 8-3" />
              </svg>
            </span>
            <span className="nav-label">Dashboard</span>
          </NavLink>
          <NavLink to="/targets" className={navClass}>
            <span className="nav-icon" aria-hidden="true">
              <svg viewBox="0 0 24 24">
                <path d="M12 3l8 4.5v9L12 21l-8-4.5v-9L12 3zM12 12l8-4.5M12 12L4 7.5M12 12v9" />
              </svg>
            </span>
            <span className="nav-label">Targets</span>
          </NavLink>
          <NavLink to="/query-insights" className={navClass}>
            <span className="nav-icon" aria-hidden="true">
              <svg viewBox="0 0 24 24">
                <path d="M4 19h16M7 15l3-3 3 2 4-5M18 8h.01" />
              </svg>
            </span>
            <span className="nav-label">Query Insights</span>
          </NavLink>
          <NavLink to="/alerts" className={navClass}>
            <span className="nav-icon" aria-hidden="true">
              <svg viewBox="0 0 24 24">
                <path d="M15 17h5l-1.4-1.4A2 2 0 0 1 18 14.2V10a6 6 0 0 0-12 0v4.2a2 2 0 0 1-.6 1.4L4 17h5m6 0a3 3 0 0 1-6 0" />
              </svg>
            </span>
            <span className="nav-label">Alerts</span>
          </NavLink>
          {me?.role === "admin" && (
            <>
              <div className="sidebar-nav-spacer" aria-hidden="true" />
              <NavLink to="/admin/users" className={({ isActive }) => `nav-btn admin-nav${isActive ? " active" : ""}`}>
                <span className="nav-icon" aria-hidden="true">
                  <svg viewBox="0 0 24 24">
                    <path d="M12 12a4 4 0 1 0 0-8 4 4 0 0 0 0 8zm-7 8a7 7 0 0 1 14 0" />
                  </svg>
                </span>
                <span className="nav-label">Admin</span>
              </NavLink>
            </>
          )}
        </nav>
        <div className="profile">
          <div className="mode-switch-block">
            <div className="mode-switch-label">View Mode</div>
            <button
              className={`mode-toggle ${uiMode === "easy" ? "easy" : "dba"}`}
              onClick={() => setUiMode(uiMode === "easy" ? "dba" : "easy")}
              type="button"
            >
              <span className="mode-pill">Easy</span>
              <span className="mode-pill">DBA</span>
            </button>
            <small>{uiMode === "easy" ? "Simple health guidance" : "Advanced DBA metrics"}</small>
          </div>
          <div>{me?.email}</div>
          <div className="role">{me?.role}</div>
          <button className="logout-btn" onClick={logout}>Logout</button>
        </div>
      </aside>
      <main className="main">
        {children}
        <div className="toast-stack" aria-live="polite" aria-atomic="true">
          {alertToasts.map((toast) => (
            <div key={toast.id} className={`alert-toast ${toast.severity || "warning"}${toast.closing ? " closing" : ""}`}>
              <div className="alert-toast-head">
                <strong>{toast.severity === "alert" ? "New Alert" : "New Warning"}</strong>
                <div className="toast-actions">
                  <button
                    type="button"
                    className="toast-view"
                    title="Open in Alerts"
                    onClick={() => {
                      navigate(`/alerts?open=${encodeURIComponent(toast.alertKey || "")}`);
                      dismissAlertToast(toast.id);
                    }}
                  >
                    <span aria-hidden="true">
                      <svg viewBox="0 0 24 24" width="13" height="13">
                        <path
                          d="M2 12s3.5-6 10-6 10 6 10 6-3.5 6-10 6-10-6-10-6zm10 3a3 3 0 1 0 0-6 3 3 0 0 0 0 6z"
                          fill="currentColor"
                        />
                      </svg>
                    </span>
                  </button>
                  <button type="button" className="toast-close" onClick={() => dismissAlertToast(toast.id)}>
                    x
                  </button>
                </div>
              </div>
              <div className="alert-toast-title">{toast.title}</div>
              <div className="alert-toast-target">{toast.target}</div>
              <div className="alert-toast-message">{toast.message}</div>
            </div>
          ))}
        </div>
      </main>
    </div>
  );
}

export function App() {
  return (
    <Routes>
      <Route path="/login" element={<LoginPage />} />
      <Route
        path="*"
        element={
          <Protected>
            <Layout>
              <Routes>
                <Route path="/" element={<DashboardPage />} />
                <Route path="/targets" element={<TargetsPage />} />
                <Route path="/targets/:id" element={<TargetDetailPage />} />
                <Route path="/query-insights" element={<QueryInsightsPage />} />
                <Route path="/alerts" element={<AlertsPage />} />
                <Route path="/admin/users" element={<AdminUsersPage />} />
              </Routes>
            </Layout>
          </Protected>
        }
      />
    </Routes>
  );
}