// The action dispatcher + HTMX callback dispatcher, ported from mnw.js:724-871.
//
// These let templates drop inline `on*` / `hx-on::` handlers so the CSP keeps
// `script-src 'self'` (no 'unsafe-inline'). The one behavioral change from the
// port: `data-action` verbs resolve against a typed `register()` registry
// FIRST, falling back to a `window.<verb>` global for handlers not yet migrated
// off the legacy `static/*.js` files. New code should `register()`, never add a
// global — the `frontend_globals` seal enforces the ratchet.

import { byId, targets } from './dom.ts';
import { showToast } from './toast.ts';

export type ActionHandler = (this: Element, ...args: string[]) => void;

const registry = new Map<string, ActionHandler>();

/** Register a named `data-action` handler. Preferred over a `window.<name>`
 *  global; the dispatcher checks the registry before the global fallback. */
export function register(name: string, fn: ActionHandler): void {
  registry.set(name, fn);
}

type BuiltinFn = (el: Element) => void;

/** Built-in verbs operating on `data-target` element ids. */
const BUILTINS: Record<string, BuiltinFn> = {
  show: (el) => targets(el).forEach((t) => t.classList.remove('hidden')),
  hide: (el) => targets(el).forEach((t) => t.classList.add('hidden')),
  toggle: (el) => targets(el).forEach((t) => t.classList.toggle('hidden')),
  click: (el) => targets(el).forEach((t) => t.click()),
  remove: (el) => targets(el).forEach((t) => t.remove()),
  'remove-self': (el) => el.remove(),
};

/** Collect positional args from `data-arg` / `data-arg2`. Exported for tests. */
export function collectArgs(el: Element): string[] {
  const args: string[] = [];
  const a1 = el.getAttribute('data-arg');
  if (a1 !== null) args.push(a1);
  const a2 = el.getAttribute('data-arg2');
  if (a2 !== null) args.push(a2);
  return args;
}

function run(el: Element, verb: string, evt: Event): void {
  if (el.hasAttribute('data-prevent')) evt.preventDefault();
  if (el.hasAttribute('data-stop')) evt.stopPropagation();
  if (verb === 'nav') {
    const href = el.getAttribute('data-href');
    if (href) window.location.href = href;
    return;
  }
  const builtin = BUILTINS[verb];
  if (builtin) {
    builtin(el);
    return;
  }
  // Registry first, then the legacy `window.<verb>` global (strangler bridge).
  const handler = registry.get(verb) ?? (window as unknown as Record<string, unknown>)[verb];
  if (typeof handler !== 'function') {
    console.warn('data-action: no handler for', verb);
    return;
  }
  (handler as ActionHandler).apply(el, collectArgs(el));
}

function listen(eventName: string, attr: string, autoPrevent: boolean): void {
  document.addEventListener(eventName, (evt) => {
    const el = (evt.target as Element | null)?.closest('[' + attr + ']');
    if (!el) return;
    if (autoPrevent) evt.preventDefault();
    const verb = el.getAttribute(attr);
    if (verb) run(el, verb, evt);
  });
}

/** Install the `data-action`/`-change`/`-input`/`-submit` dispatcher. */
export function initActionDispatcher(): void {
  listen('click', 'data-action', false);
  listen('change', 'data-change', false);
  listen('input', 'data-input', false);
  listen('submit', 'data-submit', true);
}

// ---- HTMX callback dispatcher (hx-on:: replacement), ported from mnw.js:799 ----

interface HxDetail {
  elt: HTMLElement;
  successful?: boolean;
  xhr?: XMLHttpRequest;
  parameters?: Record<string, unknown>;
}

function refreshProfileTab(): void {
  const t = document.getElementById('settings-body');
  if (t) {
    htmx.ajax('GET', '/dashboard/tabs/profile', { target: t, swap: 'innerHTML' });
  } else {
    byId('tab-profile')?.click();
  }
}

type BehaviorFn = (el: HTMLElement, evt: CustomEvent<HxDetail>) => void;

const BEHAVIORS: Record<string, BehaviorFn> = {
  'mark-added': (el) => {
    el.textContent = 'Added';
    (el as HTMLButtonElement).disabled = true;
  },
  // Faithful to the inline original: the row fades only on success, but the
  // label flips to 'Added' unconditionally (registered under data-hx-always).
  'fade-row-added': (el, evt) => {
    if (evt.detail.successful) el.closest('tr')?.classList.add('is-faded');
    el.textContent = 'Added';
  },
  'refresh-profile': () => refreshProfileTab(),
  'refresh-profile-if-verified': (_el, evt) => {
    if (evt.detail.xhr && evt.detail.xhr.responseText.indexOf('verified successfully') !== -1) {
      refreshProfileTab();
    }
  },
};

/** Install the `data-hx-*` afterRequest/configRequest dispatcher. */
export function initHxCallbackDispatcher(): void {
  document.body.addEventListener('htmx:afterRequest', (e) => {
    const evt = e as CustomEvent<HxDetail>;
    const el = evt.detail.elt;
    if (!el || !el.getAttribute) return;

    const always = el.getAttribute('data-hx-always');
    if (always && BEHAVIORS[always]) BEHAVIORS[always](el, evt);
    if (el.hasAttribute('data-hx-always-click')) byId(el.getAttribute('data-hx-always-click'))?.click();

    if (!evt.detail.successful) return;

    const form = el as HTMLFormElement;
    if (el.hasAttribute('data-hx-reset') && typeof form.reset === 'function') form.reset();
    if (el.hasAttribute('data-hx-click')) byId(el.getAttribute('data-hx-click'))?.click();
    if (el.hasAttribute('data-hx-get')) {
      const url = el.getAttribute('data-hx-get');
      const target = el.getAttribute('data-hx-target');
      if (url && target) htmx.ajax('GET', url, target);
    }
    if (el.hasAttribute('data-hx-nav')) window.location.href = el.getAttribute('data-hx-nav') ?? '';
    if (el.hasAttribute('data-hx-reload')) window.location.reload();
    if (el.hasAttribute('data-hx-toast')) {
      showToast(el.getAttribute('data-hx-toast') ?? '', el.getAttribute('data-hx-toast-type') || 'info');
    }
    const beh = el.getAttribute('data-hx-behavior');
    if (beh && BEHAVIORS[beh]) BEHAVIORS[beh](el, evt);
  });

  document.body.addEventListener('htmx:configRequest', (e) => {
    const evt = e as CustomEvent<HxDetail>;
    const el = evt.detail.elt;
    if (el?.getAttribute?.('data-hx-config') === 'publish-at-iso') {
      const params = evt.detail.parameters;
      const v = params?.publish_at;
      if (v && params) params.publish_at = new Date(v as string).toISOString();
    }
  });
}