import { useEffect } from 'react';
import { useActiveSeed } from './ActiveSeed.js';
import { useBackendConfig } from './backend-config.js';
import { BackendMatrix } from './BackendMatrix.js';

// A real Settings modal — replaces the previous "gear toggles the
// classic tab bar" behaviour. Structured into sections the way
// Trust/MetaMask do: Wallet, Backends, Display, Advanced.

export function SettingsModal({
  onClose,
  onOpenAdvanced,
}: {
  onClose: () => void;
  onOpenAdvanced: () => void;
}): JSX.Element {
  const { active, setActive } = useActiveSeed();
  const { config, toggle: toggleBackend, reset: resetBackend } = useBackendConfig();

  useEffect(() => {
    const onKey = (e: KeyboardEvent) => { if (e.key === 'Escape') onClose(); };
    window.addEventListener('keydown', onKey);
    return () => window.removeEventListener('keydown', onKey);
  }, [onClose]);

  return (
    <div className="modal-backdrop" onClick={onClose}>
      <div className="modal modal-lg" role="dialog" aria-modal="true" aria-label="Settings" onClick={(e) => e.stopPropagation()}>
        <div className="modal-header">
          <h2>Settings</h2>
          <button className="modal-close" onClick={onClose} aria-label="Close">×</button>
        </div>

        <div className="settings-body">
          <SettingsSection title="Wallet">
            {active ? (
              <SettingsRow
                label="Lock wallet"
                hint="Wipes the in-memory seed. Encrypted keystore stays saved."
                actionLabel="Lock"
                actionKind="danger"
                onAction={() => { setActive(null); onClose(); }}
              />
            ) : (
              <SettingsRow
                label="Import or unlock"
                hint="No wallet is currently loaded."
                actionLabel="Import"
                onAction={() => { onOpenAdvanced(); onClose(); }}
              />
            )}
            <SettingsRow
              label="Manage saved wallets"
              hint="Add, unlock, or delete encrypted keystore entries."
              actionLabel="Open"
              onAction={() => { onOpenAdvanced(); onClose(); }}
            />
          </SettingsSection>

          <SettingsSection title="Backends" hint="Which servers this wallet talks to. Privacy-first defaults use the P2P daemon only; enabling Blockbook adds full history at the cost of revealing addresses to the indexer operator.">
            <BackendMatrix
              config={config}
              toggle={toggleBackend}
              caps={['scan', 'broadcast'] as const}
            />
            <button className="text-btn danger" onClick={resetBackend}>
              Reset to privacy-first defaults
            </button>
          </SettingsSection>

          <SettingsSection title="Display">
            <SettingsRow
              label="Fiat price feed"
              hint="Off. Enabling would fetch DGB→USD from a public price API, revealing that this wallet is checking prices. Coming with an opt-in toggle."
              actionLabel="Coming soon"
              disabled
            />
          </SettingsSection>

          <SettingsSection title="Advanced">
            <SettingsRow
              label="Classic tabs"
              hint="The old Wallets / Balance (deep) / Send (classic) interface — with the year-picker for deep historical scans."
              actionLabel="Open"
              onAction={() => { onOpenAdvanced(); onClose(); }}
            />
            <SettingsRow
              label="About"
              hint={`DigiByte.X Wallet · recovery-first · privacy by default. Loaded from ${location.origin}. Source lives at packages/web-ui in the dgb-wallet monorepo.`}
            />
          </SettingsSection>
        </div>
      </div>
    </div>
  );
}

function SettingsSection({
  title, hint, children,
}: { title: string; hint?: string; children: React.ReactNode }): JSX.Element {
  return (
    <section className="settings-section">
      <h3>{title}</h3>
      {hint && <p className="settings-hint">{hint}</p>}
      <div className="settings-rows">{children}</div>
    </section>
  );
}

function SettingsRow({
  label, hint, actionLabel, actionKind, onAction, disabled,
}: {
  label: string;
  hint?: string;
  actionLabel?: string;
  actionKind?: 'danger';
  onAction?: () => void;
  disabled?: boolean;
}): JSX.Element {
  return (
    <div className="settings-row">
      <div className="settings-row-body">
        <div className="settings-row-label">{label}</div>
        {hint && <div className="settings-row-hint">{hint}</div>}
      </div>
      {actionLabel && (
        <button
          className={`settings-row-btn ${actionKind === 'danger' ? 'danger' : ''}`}
          onClick={onAction}
          disabled={disabled || !onAction}
        >
          {actionLabel}
        </button>
      )}
    </div>
  );
}