// Cthulhu screen reader.
// Copyright (c) 2026 Storm Dragon
// Authors: Storm Dragon, Angus Kola
// SPDX-License-Identifier: GPL-3.0-or-later

package app

import (
	"time"

	"git.stormux.org/storm/cthulhu/internal/atspi"
	"git.stormux.org/storm/cthulhu/internal/input"
)

// pendingPresentation owns one coalesced event and its captured input intent.
// Only the main event loop accesses it; timers never run presentation callbacks.
// Replacing or clearing an event disconnects its old timer from the select loop.
type pendingPresentation struct {
	event  atspi.Event
	intent input.Intent
	timer  *time.Timer
	ready  <-chan time.Time
}

func (pending *pendingPresentation) schedule(event atspi.Event, intent input.Intent, delay time.Duration) {
	pending.clear()
	pending.event, pending.intent = event, intent
	pending.timer = time.NewTimer(delay)
	pending.ready = pending.timer.C
}

func (pending *pendingPresentation) clear() {
	if pending.timer != nil {
		pending.timer.Stop()
	}
	*pending = pendingPresentation{}
}

func (pending *pendingPresentation) take() (atspi.Event, input.Intent) {
	event, intent := pending.event, pending.intent
	pending.clear()
	return event, intent
}

// pendingPresentations bounds delayed presentation to one event per family.
// Its lifetime is the event loop's lifetime, including adapter closure.
type pendingPresentations struct {
	caret            pendingPresentation
	terminalFocus    pendingPresentation
	terminalDeletion pendingPresentation
}

func (pending *pendingPresentations) clear() {
	pending.caret.clear()
	pending.terminalFocus.clear()
	pending.terminalDeletion.clear()
}