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[rbdr/forum] / src / lib / utils / glyph_hash.ts
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1export type GlyphHash = GlyphHashFragment[];
2type GlyphHashFragment = {
3 glyph: string;
4 color: string;
5};
6
7const internals = {
8 kDehyphenRegex: /[-]/g,
9 kSplitterRegex: /.{1,8}/g,
10 kGlyphs: ['☽', '☆', '♢', '♡', '╱', '╲', '╳', '〰', '▷', '⏊', '〒', '▢', '◯', '⏃', '⏀', '⏆'],
11 unexpectedUUIDLength: class UnexpectedUUIDLength extends Error {
12 name = 'UnexpectedUUIDLength';
13 message =
14 'The provided string was not a valid UUIDv4, please provide a 32 character long string';
15 }
16};
17
18// Return a glyph with color based on a 4 byte fragment of a UUIDv4
19const getGlyphHashFragment = function (uuidFragment: string): GlyphHashFragment {
20 const glyphIndex = parseInt(uuidFragment.substring(0, 2), 16) % 16;
21 return {
22 glyph: internals.kGlyphs[glyphIndex],
23 color: `#${uuidFragment.substring(2, 8)}`
24 };
25};
26
27// Return an array of glyphs based on a UUIDv4
28export const getGlyphHash = function (uuid: string): GlyphHash {
29 const dehyphenedUuid = uuid.replace(/[-]/g, '');
30
31 if (dehyphenedUuid.length !== 32) {
32 throw new internals.unexpectedUUIDLength();
33 }
34
35 const hashFragments = dehyphenedUuid.match(internals.kSplitterRegex);
36 return hashFragments.map(getGlyphHashFragment);
37};