/// Returns whether langchat is enabled for a given mob.
#define LANGCHAT_CLIENT_ENABLED(M) (M && M.client && M.client.prefs && (M.client.prefs.toggles_secondary & FLOATING_MESSAGES))

#define LANGCHAT_LONGEST_TEXT 64
#define LANGCHAT_WIDTH 96
#define LANGCHAT_MAX_ALPHA 196

// Types of message pop
#define LANGCHAT_DEFAULT_POP 0 // Normal messages.
#define LANGCHAT_PANIC_POP 1   // Fast, shaking messages.
#define LANGCHAT_FAST_POP 2    // Fast messages.

// Parameters for LANGCHAT_DEFAULT_POP
#define LANGCHAT_MESSAGE_POP_TIME 3
#define LANGCHAT_MESSAGE_POP_Y_SINK 8

// Parameters for LANGCHAT_PANIC_POP
#define LANGCHAT_MESSAGE_PANIC_POP_TIME 1
#define LANGCHAT_MESSAGE_PANIC_POP_Y_SINK 8
#define LANGCHAT_MESSAGE_PANIC_SHAKE_SIZE 6
#define LANGCHAT_MESSAGE_PANIC_SHAKE_TIMES 6
#define LANGCHAT_MESSAGE_PANIC_SHAKE_TIME_TAKEN 1

// Parameters for LANGCHAT_FAST_POP
#define LANGCHAT_MESSAGE_FAST_POP_TIME 1
#define LANGCHAT_MESSAGE_FAST_POP_Y_SINK 8

/atom/var/langchat_height = 32 // Abovetile usually
/atom/var/langchat_color = "#FFFFFF"
/atom/var/langchat_styles = ""

/// A single overhead bubble storing the text image, and the listeners it was shown to.
/datum/langchat_bubble
	var/image/bubble
	var/list/mob/listeners

/// Initializes a new bubble from a text image and a list of listeners.
/datum/langchat_bubble/New(image/bubble, list/mob/listeners)
	. = ..()
	src.bubble = bubble
	src.listeners = listeners

/// The floating bubbles currently shown for this atom.
/atom/var/list/langchat_images

/// Drops all active bubbles for this atom.
/atom/proc/langchat_drop_images()
	for(var/datum/langchat_bubble/entry as anything in langchat_images)
		if (!entry || !entry.bubble)
			continue

		for(var/mob/listener as anything in entry.listeners)
			if (!listener || !listener.client)
				continue
			listener.client.images -= entry.bubble
	langchat_images = null

/atom/proc/get_maptext_x_offset(image/maptext_image)
	return (world.icon_size / 2) - (maptext_image.maptext_width / 2)

/atom/movable/get_maptext_x_offset(image/maptext_image)
	return (bound_width / 2) - (maptext_image.maptext_width / 2)

/mob/get_maptext_x_offset(image/maptext_image)
	return (icon_size / 2) - (maptext_image.maptext_width / 2)

/// Constructs a single floating langchat bubble showing maptext_string to the given listeners.
/atom/proc/langchat_build_image(maptext_string, list/mob/listeners, override_color, animation_style = LANGCHAT_DEFAULT_POP, list/additional_styles = list("langchat"))
	if(!length(listeners))
		return

	var/image/bubble = image(null, src)
	bubble.layer = 20
	bubble.plane = RUNECHAT_PLANE
	bubble.appearance_flags = NO_CLIENT_COLOR|KEEP_APART|RESET_COLOR|RESET_TRANSFORM
	bubble.maptext_y = langchat_height - LANGCHAT_MESSAGE_POP_Y_SINK
	bubble.maptext_height = 64
	bubble.alpha = 0
	bubble.color = override_color ? override_color : langchat_color
	if(appearance_flags & PIXEL_SCALE)
		bubble.appearance_flags |= PIXEL_SCALE
	langchat_configure_bubble(bubble, override_color)

	bubble.maptext = generate_text_image(maptext_string, additional_styles)
	bubble.maptext_width = LANGCHAT_WIDTH
	bubble.maptext_x = get_maptext_x_offset(bubble)
	bubble.loc = isturf(loc) ? src : recursive_holder_check(src)

	for(var/mob/listener as anything in listeners)
		listener.client.images += bubble

	animate_style(bubble, animation_style)
	LAZYADD(langchat_images, new /datum/langchat_bubble(bubble, listeners))

/// Per-type appearance tweaks applied to a freshly built bubble.
/atom/proc/langchat_configure_bubble(image/bubble, override_color)
	return

/mob/abstract/ghost/langchat_configure_bubble(image/bubble, override_color)
	if(!override_color)
		bubble.color = "#c51fb7"
	bubble.appearance_flags |= RESET_ALPHA

/// Floats flat text to everybody who can see it.
/atom/proc/langchat_speech(message, list/mob/listeners, override_color, animation_style = LANGCHAT_DEFAULT_POP, list/additional_styles = list("langchat"))
	langchat_drop_images()

	var/list/mob/shown = list()
	for(var/mob/listener in listeners)
		if(!LANGCHAT_CLIENT_ENABLED(listener) || listener.ear_deaf)
			continue
		shown += listener
	if(!length(shown))
		return

	langchat_build_image(message, shown, override_color, animation_style, additional_styles)

	var/timer = (length(message) / LANGCHAT_LONGEST_TEXT) * 4 SECONDS + 2 SECONDS
	addtimer(CALLBACK(src, TYPE_PROC_REF(/atom, langchat_drop_images)), timer, TIMER_UNIQUE|TIMER_OVERRIDE|TIMER_NO_HASH_WAIT)

/// Floats a say message to every listener in view. Each listener receives their own perceived text based on
/// their comprehension of the spoken languages. Identical text is grouped into a single bubble for performance.
/atom/proc/langchat_say_message(datum/say_message/msg, list/mob/listeners, override_color, animation_style = LANGCHAT_DEFAULT_POP, list/additional_styles = list("langchat"))
	langchat_drop_images()

	// Group listeners by exact text perceived.
	var/list/groups = list()
	for(var/mob/listener in listeners)
		if(!LANGCHAT_CLIENT_ENABLED(listener) || listener.ear_deaf)
			continue
		var/perceived = msg.plain_text_for(listener)
		if(!length(perceived))
			continue
		var/list/group = groups[perceived]
		if(!group)
			group = list()
			groups[perceived] = group
		group += listener
	if(!length(groups))
		return

	for(var/perceived in groups)
		langchat_build_image(perceived, groups[perceived], override_color, animation_style, additional_styles)

	// One-off timer for duration. Disappears for all listeners at the same time.
	var/timer = (length(msg.to_string()) / LANGCHAT_LONGEST_TEXT) * 4 SECONDS + 2 SECONDS
	addtimer(CALLBACK(src, TYPE_PROC_REF(/atom, langchat_drop_images)), timer, TIMER_UNIQUE|TIMER_OVERRIDE|TIMER_NO_HASH_WAIT)

/// Builds the maptext span for a floating message.
/atom/proc/generate_text_image(message, list/additional_styles = list("langchat"))
	var/list/styles = additional_styles ? additional_styles.Copy() : list()
	var/text_to_display = message
	var/use_mob_style = TRUE

	if(length(text_to_display) > LANGCHAT_LONGEST_TEXT)
		text_to_display = copytext_char(text_to_display, 1, LANGCHAT_LONGEST_TEXT + 1) + "..."
	if(styles.Find("emote"))
		styles.Remove("emote")
		use_mob_style = FALSE
		var/image/r_icon = image('icons/mob/chat_icons.dmi', icon_state = "emote")
		text_to_display = "\icon[r_icon]&zwsp;[text_to_display]"

	return "<span class='center [styles.Join(" ")] [use_mob_style ? langchat_styles : ""] langchat'>[text_to_display]</span>"

/// Animates the given maptext image.
/atom/proc/animate_style(var/image/bubble, animation_style = LANGCHAT_DEFAULT_POP)
	if(bubble)
		switch(animation_style)
			if(LANGCHAT_DEFAULT_POP)
				bubble.alpha = 0
				animate(bubble, pixel_y = bubble.pixel_y + LANGCHAT_MESSAGE_POP_Y_SINK, alpha = LANGCHAT_MAX_ALPHA, time = LANGCHAT_MESSAGE_POP_TIME)
			if(LANGCHAT_PANIC_POP)
				bubble.alpha = LANGCHAT_MAX_ALPHA
				animate(bubble, pixel_y = bubble.pixel_y + LANGCHAT_MESSAGE_PANIC_POP_Y_SINK, time = LANGCHAT_MESSAGE_PANIC_POP_TIME)
				animate(pixel_x = bubble.pixel_x - LANGCHAT_MESSAGE_PANIC_SHAKE_SIZE, time = LANGCHAT_MESSAGE_PANIC_SHAKE_TIME_TAKEN, easing = CUBIC_EASING)
				for(var/i = 1 to LANGCHAT_MESSAGE_PANIC_SHAKE_TIMES)
					animate(pixel_x = bubble.pixel_x + 2*LANGCHAT_MESSAGE_PANIC_SHAKE_SIZE, time = 2*LANGCHAT_MESSAGE_PANIC_SHAKE_TIME_TAKEN, easing = CUBIC_EASING)
					animate(pixel_x = bubble.pixel_x - 2*LANGCHAT_MESSAGE_PANIC_SHAKE_SIZE, time = LANGCHAT_MESSAGE_PANIC_SHAKE_TIME_TAKEN, easing = CUBIC_EASING)
				animate(pixel_x = bubble.pixel_x + LANGCHAT_MESSAGE_PANIC_SHAKE_SIZE, time = LANGCHAT_MESSAGE_PANIC_SHAKE_TIME_TAKEN, easing = CUBIC_EASING)
			if(LANGCHAT_FAST_POP)
				bubble.alpha = 0
				animate(bubble, pixel_y = bubble.pixel_y + LANGCHAT_MESSAGE_FAST_POP_Y_SINK, alpha = LANGCHAT_MAX_ALPHA, time = LANGCHAT_MESSAGE_FAST_POP_TIME)

/// Attempts to return what's holding this item if being contained by something. e.g. Cortical borer returns their host.
/proc/recursive_holder_check(obj/item/held_item, recursion_limit = 3)
	if(recursion_limit <= 0)
		return held_item
	if(!held_item.loc || isturf(held_item.loc))
		return held_item
	recursion_limit--
	return recursive_holder_check(held_item.loc, recursion_limit)