File size: 3,483 Bytes
09f13ea
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
import type { Action } from "svelte/action";

export enum ObservedElements {
	BottomActions = "bottom-actions",
	TokenCountEnd = "token-count-end",
	TokenCountStart = "token-count-start",
	// Add other elements here as needed
}

type ObservedData = {
	rect: {
		width: number;
		height: number;
		top: number;
		left: number;
		right: number;
		bottom: number;
	};
	offset: {
		width: number;
		height: number;
		top: number;
		left: number;
		right: number;
		bottom: number;
	};
};

export const observed: Record<ObservedElements, ObservedData> = $state(
	Object.values(ObservedElements).reduce(
		(acc, key) => {
			acc[key] = {
				rect: {
					width: 0,
					height: 0,
					top: 0,
					left: 0,
					right: 0,
					bottom: 0,
				},
				offset: {
					width: 0,
					height: 0,
					top: 0,
					left: 0,
					right: 0,
					bottom: 0,
				},
			};
			return acc;
		},
		{} as Record<ObservedElements, ObservedData>
	)
);

type ObserveArgs = {
	name: ObservedElements;
};

function getOffsetPosition(el: HTMLElement) {
	let top = 0;
	let left = 0;
	const width = el.offsetWidth;
	const height = el.offsetHeight;

	while (el) {
		top += el.offsetTop;
		left += el.offsetLeft;
		el = el.offsetParent as HTMLElement;
	}

	return { top, left, width, height, right: left + width, bottom: top + height };
}

export const observe: Action<HTMLElement, ObserveArgs> = (node, args) => {
	let resizeObserver: ResizeObserver;

	function setVars(name: ObservedElements) {
		// 1. Standard rect (includes transforms)
		const rect = node.getBoundingClientRect();
		document.documentElement.style.setProperty(`--${name}-width`, `${rect.width}px`);
		document.documentElement.style.setProperty(`--${name}-height`, `${rect.height}px`);
		document.documentElement.style.setProperty(`--${name}-top`, `${rect.top}px`);
		document.documentElement.style.setProperty(`--${name}-left`, `${rect.left}px`);
		document.documentElement.style.setProperty(`--${name}-right`, `${rect.right}px`);
		document.documentElement.style.setProperty(`--${name}-bottom`, `${rect.bottom}px`);

		// 2. Offset position (ignores transforms)
		const offset = getOffsetPosition(node);
		document.documentElement.style.setProperty(`--${name}-width-offset`, `${offset.width}px`);
		document.documentElement.style.setProperty(`--${name}-height-offset`, `${offset.height}px`);
		document.documentElement.style.setProperty(`--${name}-top-offset`, `${offset.top}px`);
		document.documentElement.style.setProperty(`--${name}-left-offset`, `${offset.left}px`);
		document.documentElement.style.setProperty(`--${name}-right-offset`, `${offset.right}px`);
		document.documentElement.style.setProperty(`--${name}-bottom-offset`, `${offset.bottom}px`);

		observed[name] = {
			rect,
			offset,
		};
	}

	function update(args: ObserveArgs) {
		if (resizeObserver) {
			resizeObserver.disconnect();
		}

		resizeObserver = new ResizeObserver(() => {
			setVars(args.name);
		});
		resizeObserver.observe(node);

		// Listen for scroll and resize events
		window.addEventListener("scroll", onWindowChange, true);
		window.addEventListener("resize", onWindowChange, true);

		setVars(args.name); // Initial set after observing
	}

	function onWindowChange() {
		setVars(args.name);
	}

	update(args); // Initial setup

	function destroy() {
		resizeObserver.disconnect();
		window.removeEventListener("scroll", onWindowChange, true);
		window.removeEventListener("resize", onWindowChange, true);
	}

	return {
		update,
		destroy,
	};
};