class_name EventTimeline
extends CanvasLayer
## Body-camera timeline for the shift review (PLAN.md: Evidence and Body Camera).
## First version is a text timeline of the structured incident events ADR-0005
## already stores: step through them with the arrow keys or the buttons. No live
## 3D replay.

signal closed()

const Strings := preload("res://src/core/strings.gd")
const UiArt := preload("res://src/game/ui/art.gd")
const UiStyles := preload("res://src/game/ui/ui_styles.gd")
const UiFocus := preload("res://src/game/ui/ui_focus.gd")

var events: Array[Dictionary] = []
var index := 0
var _list_label: Label = null
var _detail_label: Label = null
var _counter_label: Label = null
var _prev_button: Button = null
var _next_button: Button = null
var _close_button: Button = null
var _root: Control = null

func _init() -> void:
	name = "EventTimeline"
	layer = 32
	_build()
	hide()

func _build() -> void:
	_root = Control.new()
	_root.name = "TimelineRoot"
	_root.set_anchors_preset(Control.PRESET_FULL_RECT)
	_root.mouse_filter = Control.MOUSE_FILTER_STOP
	add_child(_root)

	var panel_rect := Rect2(0.293, 0.0, 0.345, 1.0)
	var art := UiArt.new()
	if not art.add_screen_backdrop(_root, "body_camera_timeline", panel_rect):
		var dim := ColorRect.new()
		dim.color = Color(0.02, 0.03, 0.05, 0.9)
		dim.set_anchors_preset(Control.PRESET_FULL_RECT)
		dim.mouse_filter = Control.MOUSE_FILTER_IGNORE
		_root.add_child(dim)

	var column_host := MarginContainer.new()
	column_host.set_anchor(SIDE_LEFT, panel_rect.position.x)
	column_host.set_anchor(SIDE_TOP, panel_rect.position.y)
	column_host.set_anchor(SIDE_RIGHT, panel_rect.position.x + panel_rect.size.x)
	column_host.set_anchor(SIDE_BOTTOM, panel_rect.position.y + panel_rect.size.y)
	column_host.add_theme_constant_override("margin_left", 16)
	column_host.add_theme_constant_override("margin_right", 16)
	column_host.add_theme_constant_override("margin_top", 18)
	column_host.add_theme_constant_override("margin_bottom", 18)
	_root.add_child(column_host)

	var column := VBoxContainer.new()
	column.add_theme_constant_override("separation", 8)
	column_host.add_child(column)

	var title := Label.new()
	title.text = Strings.lookup("timeline.title")
	title.add_theme_font_size_override("font_size", 20)
	title.autowrap_mode = TextServer.AUTOWRAP_WORD_SMART
	title.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	column.add_child(title)

	_counter_label = Label.new()
	_counter_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	_counter_label.add_theme_color_override("font_color", Color(0.72, 0.78, 0.9))
	column.add_child(_counter_label)

	_detail_label = Label.new()
	_detail_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	_detail_label.autowrap_mode = TextServer.AUTOWRAP_WORD_SMART
	_detail_label.custom_minimum_size = Vector2(0, 44)
	_detail_label.add_theme_font_size_override("font_size", 15)
	column.add_child(_detail_label)

	var list_scroll := ScrollContainer.new()
	list_scroll.size_flags_vertical = Control.SIZE_EXPAND_FILL
	list_scroll.horizontal_scroll_mode = ScrollContainer.SCROLL_MODE_DISABLED
	column.add_child(list_scroll)
	_list_label = Label.new()
	_list_label.horizontal_alignment = HORIZONTAL_ALIGNMENT_LEFT
	_list_label.autowrap_mode = TextServer.AUTOWRAP_WORD_SMART
	_list_label.size_flags_horizontal = Control.SIZE_EXPAND_FILL
	_list_label.add_theme_font_size_override("font_size", 13)
	_list_label.add_theme_color_override("font_color", Color(0.8, 0.84, 0.9))
	list_scroll.add_child(_list_label)

	var row := HBoxContainer.new()
	row.alignment = BoxContainer.ALIGNMENT_CENTER
	row.add_theme_constant_override("separation", 10)
	column.add_child(row)

	_prev_button = Button.new()
	_prev_button.name = "PrevButton"
	_prev_button.text = Strings.lookup("timeline.prev")
	_prev_button.pressed.connect(func(): step(-1))
	UiStyles.apply_button(_prev_button, 15, true)
	row.add_child(_prev_button)

	_next_button = Button.new()
	_next_button.name = "NextButton"
	_next_button.text = Strings.lookup("timeline.next")
	_next_button.pressed.connect(func(): step(1))
	UiStyles.apply_button(_next_button, 15, true)
	row.add_child(_next_button)

	_close_button = Button.new()
	_close_button.name = "CloseButton"
	_close_button.text = Strings.lookup("timeline.close")
	_close_button.pressed.connect(_on_close)
	UiStyles.apply_button(_close_button, 15, true)
	row.add_child(_close_button)

	var hint := Label.new()
	hint.text = Strings.lookup("timeline.hint")
	hint.autowrap_mode = TextServer.AUTOWRAP_WORD_SMART
	hint.horizontal_alignment = HORIZONTAL_ALIGNMENT_CENTER
	hint.add_theme_color_override("font_color", Color(0.55, 0.58, 0.65))
	column.add_child(hint)

## Flatten every incident's event stream into one time-ordered list.
func flatten(review: Dictionary) -> Array[Dictionary]:
	var out: Array[Dictionary] = []
	var incidents: Dictionary = review.get("incidents", {})
	var list: Array = incidents.get("incidents", [])
	for incident in list:
		var incident_id := str(incident.get("id", ""))
		var npc_id := str(incident.get("npc_id", ""))
		for event in incident.get("events", []):
			var row: Dictionary = (event as Dictionary).duplicate()
			row["incident_id"] = incident_id
			row["npc_id"] = npc_id
			out.append(row)
	out.sort_custom(func(a, b): return int(a.get("at_ms", 0)) < int(b.get("at_ms", 0)))
	return out

func show_timeline(review: Dictionary) -> void:
	events = flatten(review)
	index = 0
	visible = true
	_root.visible = true
	Input.set_mouse_mode(Input.MOUSE_MODE_VISIBLE)
	_refresh()
	var first := UiFocus.first_enabled([_prev_button, _next_button, _close_button])
	if first:
		first.grab_focus()

func step(direction: int) -> void:
	if events.is_empty():
		return
	index = clampi(index + direction, 0, events.size() - 1)
	_refresh()

func close() -> void:
	visible = false
	_root.visible = false
	closed.emit()

func _on_close() -> void:
	close()

func _refresh() -> void:
	var has_events := not events.is_empty()
	if _prev_button:
		_prev_button.disabled = not has_events or index <= 0
	if _next_button:
		_next_button.disabled = not has_events or index >= events.size() - 1
	UiFocus.link([_prev_button, _next_button, _close_button])
	# A disabled control cannot keep focus; move to the other end of the row.
	if _prev_button and _prev_button.disabled and _prev_button.has_focus() and _close_button:
		_close_button.grab_focus()
	if _next_button and _next_button.disabled and _next_button.has_focus() and _close_button:
		_close_button.grab_focus()
	if not has_events:
		_counter_label.text = Strings.lookup("timeline.empty")
		_detail_label.text = ""
		_list_label.text = ""
		return
	var event: Dictionary = events[index]
	_counter_label.text = Strings.fmt("timeline.position", [index + 1, events.size()])
	_detail_label.text = describe(event)
	var lines: Array[String] = []
	var from := maxi(0, index - 6)
	var to := mini(events.size(), from + 13)
	for i in range(from, to):
		var marker := ">" if i == index else " "
		lines.append("%s %s" % [marker, describe(events[i])])
	_list_label.text = "\n".join(lines)

## One-line summary of a recorded event. Public so it is headless-testable.
func describe(event: Dictionary) -> String:
	var type := str(event.get("type", "event"))
	var npc := str(event.get("npc_id", ""))
	var stamp := _stamp(int(event.get("at_ms", 0)))
	var detail := ""
	match type:
		"player_action":
			detail = "%s (L%d)" % [str(event.get("action", "")), int(event.get("level", 0))]
		"access_check":
			var evidence: Dictionary = event.get("evidence", {})
			detail = "decided %s (verified %s)" % [
				"allow" if bool(evidence.get("decided", false)) else "deny",
				"yes" if bool(evidence.get("verified_granted", false)) else "no",
			]
		"recognition_decision":
			detail = "recognized"
		"reason_requested":
			var reply := str(event.get("reply", ""))
			detail = "reason: \"%s\"" % (reply if reply != "" else "no answer")
		"body_camera":
			detail = "body camera %s (%s)" % [
				"on" if bool(event.get("on", false)) else "off",
				str(event.get("reason", "")),
			]
		"responder_action":
			detail = "%s response: %s" % [str(event.get("call_type", "assist")), str(event.get("outcome", ""))]
		"evacuation":
			detail = "evacuated"
		"investigation_opened":
			detail = "investigation: %s" % str(event.get("reason", ""))
		_:
			detail = type
	return "%s  %s  %s" % [stamp, npc, detail]

func _stamp(at_ms: int) -> String:
	if at_ms <= 0:
		return "--:--"
	var total := at_ms / 1000
	return "%02d:%02d" % [total / 60, total % 60]

func _unhandled_input(event: InputEvent) -> void:
	if not visible:
		return
	if event.is_action_pressed("ui_cancel"):
		close()
		get_viewport().set_input_as_handled()
		return
	if event is InputEventKey and event.pressed and not event.echo:
		match event.keycode:
			KEY_LEFT, KEY_A:
				step(-1)
				get_viewport().set_input_as_handled()
			KEY_RIGHT, KEY_D:
				step(1)
				get_viewport().set_input_as_handled()