directus

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const IPTC_ENTRY_TYPES = new Map([
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	[0x78, 'caption'],
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	[0x6e, 'credit'],
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	[0x19, 'keywords'],
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	[0x37, 'dateCreated'],
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	[0x50, 'byline'],
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	[0x55, 'bylineTitle'],
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	[0x7a, 'captionWriter'],
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	[0x69, 'headline'],
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	[0x74, 'copyright'],
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	[0x0f, 'category'],
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]);
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const IPTC_ENTRY_MARKER = Buffer.from([0x1c, 0x02]);
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export function parseIptc(buffer: Buffer): Record<string, unknown> {
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	if (!Buffer.isBuffer(buffer)) return {};
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	const iptc: Record<string, any> = {};
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	let lastIptcEntryPos = buffer.indexOf(IPTC_ENTRY_MARKER);
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	while (lastIptcEntryPos !== -1) {
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		lastIptcEntryPos = buffer.indexOf(IPTC_ENTRY_MARKER, lastIptcEntryPos + IPTC_ENTRY_MARKER.byteLength);
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		const iptcBlockTypePos = lastIptcEntryPos + IPTC_ENTRY_MARKER.byteLength;
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		const iptcBlockSizePos = iptcBlockTypePos + 1;
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		const iptcBlockDataPos = iptcBlockSizePos + 2;
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		const iptcBlockType = buffer.readUInt8(iptcBlockTypePos);
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		const iptcBlockSize = buffer.readUInt16BE(iptcBlockSizePos);
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		if (!IPTC_ENTRY_TYPES.has(iptcBlockType)) {
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			continue;
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		}
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		const iptcBlockTypeId = IPTC_ENTRY_TYPES.get(iptcBlockType);
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		const iptcData = buffer.subarray(iptcBlockDataPos, iptcBlockDataPos + iptcBlockSize).toString();
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		if (iptcBlockTypeId) {
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			if (iptc[iptcBlockTypeId] == null) {
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				iptc[iptcBlockTypeId] = iptcData;
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			} else if (Array.isArray(iptc[iptcBlockTypeId])) {
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				iptc[iptcBlockTypeId].push(iptcData);
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			} else {
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				iptc[iptcBlockTypeId] = [iptc[iptcBlockTypeId], iptcData];
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			}
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		}
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	}
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	return iptc;
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}
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export function parseXmp(buffer: Buffer): Record<string, unknown> {
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	const xmp: Record<string, unknown> = {};
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	['title', 'description', 'rights', 'creator', 'subject'].forEach((x) => {
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		const tagRegex = new RegExp(`<dc:${x}>(.*?)</dc:${x}>`, 'smig'),
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			tagMatches = tagRegex.exec(buffer.toString());
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		if (!tagMatches || tagMatches.length === 0) {
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			return;
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		}
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		const value = tagMatches[1]?.trim();
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		if (value?.toLowerCase().indexOf('<rdf:bag>') === 0) {
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			const r = new RegExp('<rdf:li>(.*?)</rdf:li>', 'smig');
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			let match = r.exec(value);
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			const result = [];
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			while (match) {
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				result.push(match[1]);
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				match = r.exec(value);
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			}
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			xmp[x] = result;
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		} else {
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			xmp[x] = value?.replace(/<[^>]*>?/gm, '').trim();
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		}
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	});
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	return xmp;
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}
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