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

package app

import (
	"strings"

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

// handleLifecycle returns true when window or document lifecycle consumes an event.
func (handler *accessibilityEventHandler) handleLifecycle(event atspi.Event) bool {
	state := handler.state
	logger := handler.logger
	speech := handler.speech
	browser := handler.browser
	objectReview := handler.objectReview
	focusGate := handler.focusGate
	clearOwnedFocus := handler.clearOwnedFocus
	if event.Type == atspi.WindowActivatedEvent && strings.TrimSpace(event.WindowTitle) == speechHistoryWindowTitle {
		state.historyWindow = eventWindow(event)
	}
	if event.Type == atspi.WindowDeactivatedEvent || event.Type == atspi.WindowDestroyedEvent {
		recentCommand := browser != nil && browser.recentConsumedCommand()
		if transientForegroundDeactivation(event, state.foregroundState) {
			// Native correlation, not a time heuristic, confirms that
			// this is still the actual foreground client.
			recentCommand = true
		}
		if state.owner.end(event, recentCommand) {
			clearOwnedFocus()
			logger.Debug("cleared accessible window ownership", "type", event.Type, "application", event.Source.ApplicationName, "bus", event.Window.BusName, "window_path", event.Window.Path)
		} else {
			logger.Debug("ignored unrelated or transient window lifecycle", "type", event.Type, "application", event.Source.ApplicationName, "bus", event.Window.BusName, "window_path", event.Window.Path)
		}
		return true
	}
	if event.Type == atspi.DefunctStateEvent {
		windowEnded, focusEnded := state.owner.defunct(event)
		if focusEnded {
			clearOwnedFocus()
			logger.Debug("cleared defunct accessibility ownership", "window_ended", windowEnded, "application", event.Source.ApplicationName, "bus", event.Source.BusName, "source_path", event.Source.Path)
		}
		return true
	}
	if browser != nil && !focusGate.Suspended() &&
		(event.Type == atspi.DocumentReloadEvent || event.Type == atspi.DocumentLoadStoppedEvent || event.Type == atspi.BusyStateEvent) {
		if !state.owner.containsLoad(event) {
			logger.Debug("ignored document lifecycle outside owned focus", "type", event.Type,
				"bus", event.Source.BusName, "window_path", event.Window.Path)
			return true
		}
		if event.FocusOutsideDocument.Valid() {
			logger.Debug("kept browser chrome focus during document lifecycle", "type", event.Type)
			return true
		}
		if event.Type == atspi.BusyStateEvent && event.Detail1 == 0 &&
			state.chromeLoadedDocument == event.Source.ID() && state.chromeLoadedWindow == eventWindow(event) &&
			state.owner.focus.Valid() && state.owner.focus != event.Source.ID() &&
			!(browser.ready && browser.document == event.Source.ID()) {
			logger.Debug("kept verified chrome focus during document completion")
			return true
		}
		if event.Type == atspi.DocumentReloadEvent || event.Type == atspi.BusyStateEvent && event.Detail1 != 0 {
			if state.loadingDocument != event.Source.ID() {
				state.loadingDocument = event.Source.ID()
				state.loadedDocument = atspi.ObjectID{}
				if event.Type == atspi.BusyStateEvent {
					speech.Enqueue(speechRequest{Text: "Loading. Please wait.", Role: "system", Cause: "document-loading"})
				}
			}
			browser.loading()
			if objectReview != nil {
				objectReview.ResetDocument(event.Source.ID())
			}
		} else {
			state.pending.caret.clear()
			state.documentLineFocus = atspi.ObjectID{}
			state.documentLineRequest = 0
			state.documentLineEvent = atspi.Event{}
			if state.loadedDocument != event.Source.ID() {
				state.lastSpokenPath, state.lastSpokenText, state.lastSound = "", "", ""
			}
			state.owner.follow(event)
			state.current = event.Source
			state.focusedID = event.Source.ID()
			if event.Type == atspi.BusyStateEvent && state.loadedDocument != event.Source.ID() {
				speech.Enqueue(speechRequest{Text: finishedLoadingText(event.Source.Name), Role: "system", Cause: "document-loaded", Append: true})
				state.loadedDocument = event.Source.ID()
			}
			state.loadingDocument = atspi.ObjectID{}
			browser.loaded(event.Source.ID())
			if objectReview != nil {
				objectReview.ResetDocument(event.Source.ID())
			}
		}
		return true
	}
	if event.Type == atspi.DocumentLoadCompleteEvent && browser != nil && !focusGate.Suspended() {
		if !state.owner.containsLoad(event) {
			logger.Debug("ignored document load outside owned focus", "bus", event.Source.BusName, "window_path", event.Window.Path)
			return true
		}
		alreadyAnnounced := state.loadedDocument == event.Source.ID() && state.loadingDocument != event.Source.ID()
		state.pending.caret.clear()
		state.documentLineFocus = atspi.ObjectID{}
		state.documentLineRequest = 0
		state.documentLineEvent = atspi.Event{}
		if !alreadyAnnounced {
			state.lastSpokenPath, state.lastSpokenText, state.lastSound = "", "", ""
		}
		if event.FocusOutsideDocument.Valid() {
			state.chromeLoadedDocument = event.Source.ID()
			state.chromeLoadedWindow = eventWindow(event)
			browser.loaded(event.FocusOutsideDocument)
			if objectReview != nil {
				objectReview.ResetDocument(event.FocusOutsideDocument)
			}
			logger.Debug("kept browser chrome focus during document load")
			return true
		}
		state.chromeLoadedDocument = atspi.ObjectID{}
		state.chromeLoadedWindow = atspi.ObjectID{}
		state.owner.follow(event)
		state.current = event.Source
		state.focusedID = event.Source.ID()
		browser.loaded(event.Source.ID())
		if objectReview != nil {
			objectReview.ResetDocument(event.Source.ID())
			if event.DocumentFragment != "" {
				if err := objectReview.JumpToDocumentFragment(event.DocumentFragment); err != nil {
					logger.Warn("queue document fragment navigation", "error", err)
				}
			}
		}
		if !alreadyAnnounced {
			speech.Enqueue(speechRequest{Text: finishedLoadingText(event.Source.Name), Role: "system", Cause: "document-loaded", Append: true})
		}
		state.loadingDocument = atspi.ObjectID{}
		state.loadedDocument = event.Source.ID()
		return true
	}
	return false
}

// Keyboard grabs can make GTK emit deactivate/activate while X11 still owns
// the same foreground client. Native correlation is stronger than a timer.
func transientForegroundDeactivation(event atspi.Event, foreground atspi.ForegroundState) bool {
	return event.Type == atspi.WindowDeactivatedEvent && !event.ForegroundMismatch && foreground.Client.Known && foreground.Client.Window != 0
}

func finishedLoadingText(name string) string {
	name = strings.TrimSpace(name)
	if name == "" {
		return "Finished loading."
	}
	return "Finished loading " + name + "."
}