class_name NotificationDisplay extends Control

@export var icon: TextureRect
@export var label: Label
@onready var _container: HBoxContainer = $HBoxContainer

var _player: Node2D = null
var _sprite_size: Vector2 = Vector2.ZERO
var _origin_offset: float = 0.0
var _follow_player: bool = false

var _connector_line: Line2D = null
var _connector_visible: bool = false


func _ready() -> void:
    # Start fully transparent so the initial (0,0) position is invisible.
    # This runs during add_child() before any rendering occurs.
    modulate.a = 0.0

    # 4px horizontal padding inside the background box
    _container.add_theme_constant_override("margin_left", 4)
    _container.add_theme_constant_override("margin_right", 4)


func show_notification(weapon_name: String, player_node: Node2D, player_sprite_size: Vector2, origin_offset: float) -> void:
    modulate.a = 0.0

    label.add_theme_font_size_override("font_size", 8)
    label.text = weapon_name

    # Auto-load icon from graphics folder matching the weapon name
    var icon_path = "res://graphics/" + weapon_name.to_lower() + ".png"
    if ResourceLoader.exists(icon_path):
        icon.texture = load(icon_path)
    else:
        icon.texture = null

    _player = player_node
    _player.tree_exiting.connect(queue_free)
    _sprite_size = player_sprite_size
    _origin_offset = origin_offset
    _follow_player = false # Disable movement for testing

    # Wait one frame for layout to resolve shrink-to-fit widths
    await get_tree().process_frame

    # Use container's natural width, but fix height at 16px
    size = Vector2(_container.size.x, 16.0)

    # Calculate target position
    _update_position()
    var target_pos = position

    # Start 10px above destination (already transparent from line 17)
    position.y = target_pos.y - 10.0

    # Create connector line immediately so it fades in with the notification
    _connector_line = Line2D.new()
    _connector_line.default_color = Color(1.0, 1.0, 1.0, 0.0)
    _connector_line.width = 1.0
    add_child(_connector_line)
    _connector_visible = true

    # Pause following during fade-in so the tween isn't overridden by _process
    _follow_player = false

    # Fade in notification and connector together, slide into position with overshoot
    var tween = create_tween().set_parallel()
    tween.tween_property(self, "modulate:a", 1.0, 0.3)
    tween.tween_property(_connector_line, "default_color:a", 1.0, 0.3)
    var move_tween = tween.tween_property(self, "position:y", target_pos.y, 0.3)
    move_tween.set_trans(Tween.TRANS_ELASTIC).set_ease(Tween.EASE_OUT)

    # Wait for fade-in to finish, then resume following
    await tween.finished
    _follow_player = true

    # Stay fully visible for a moment before fading
    await get_tree().create_timer(0.5).timeout

    # Record current position as the fade-out starting point
    await get_tree().process_frame
    var fade_start_y = position.y

    # Fade out and drift downward with steady acceleration
    _follow_player = false
    var fade_out = create_tween().set_parallel()
    fade_out.tween_property(self, "modulate:a", 0.0, .35)
    var drift = fade_out.tween_property(self, "position:y", fade_start_y + 7, .3)
    drift.set_trans(Tween.TRANS_QUAD).set_ease(Tween.EASE_IN)
    await fade_out.finished
    queue_free()


func _process(_delta: float) -> void:
    if _follow_player and _player:
        _update_position()
    if _connector_visible and _player:
        _update_connector()


func _update_position() -> void:
    if _player == null:
        return

    var player_pos = _player.position

    # Y position uses the weapon origin offset from player center
    var notif_y = player_pos.y + _origin_offset - (size.y / 2.0)

    # X position is 10px to the right of player's sprite edge
    var right_edge = player_pos.x + (_sprite_size.x / 2.0)
    var notif_x = right_edge + 10.0

    var is_flipped = false

    # Clamp to screen bounds — flip to left if it would go off-screen right
    var viewport_size = get_viewport_rect().size
    if notif_x + size.x > viewport_size.x:
        is_flipped = true
        var left_edge = player_pos.x - (_sprite_size.x / 2.0)
        notif_x = left_edge - 10.0 - size.x

    # Swap icon/label order so the icon is always closest to the player
    if is_flipped:
        _container.move_child(label, 0)
        _container.move_child(icon, 1)
    else:
        _container.move_child(icon, 0)
        _container.move_child(label, 1)

    # Final clamp: ensure the entire notification is within screen bounds
    notif_x = clamp(notif_x, 0, viewport_size.x - size.x)
    notif_y = clamp(notif_y, 0, viewport_size.y - size.y)

    position = Vector2(notif_x, notif_y)


func _update_connector() -> void:
    if _connector_line == null or _player == null:
        return

    # Icon position in the notification's local space
    var icon_pos = _container.position + icon.position
    var icon_mid_y = icon_pos.y + icon.size.y / 2.0

    # Point 0: edge of the container closest to the icon, at icon's vertical midpoint
    var point0: Vector2
    var direction: float

    if _container.get_child(0) == icon:
        # Icon on the left (not flipped) — container's left edge, line goes left toward player
        point0 = Vector2(_container.position.x, icon_mid_y)
        direction = -1.0
    else:
        # Icon on the right (flipped) — container's right edge, line goes right toward player
        point0 = Vector2(_container.position.x + _container.size.x, icon_mid_y)
        direction = 1.0

    # Point 1: 8px straight from point 0 toward the player
    const SEGMENT_ORIGIN: float = 8.0 # length of initial segment from origin
    var point1 = Vector2(point0.x + SEGMENT_ORIGIN * direction, icon_mid_y)

    # Point 2: player's origin + ENDPOINT_OFFSET, converted to notification's local space
    const ENDPOINT_OFFSET = Vector2(4, 7) # offset from player's origin to connector endpoint
    var target = _player.position + Vector2(+ENDPOINT_OFFSET.x, _origin_offset + ENDPOINT_OFFSET.y)
    var point2 = target - position

    _connector_line.points = PackedVector2Array([point0, point1, point2])