Memory refinement WIP

src/utils.ts

@@ -0,0 +1,82 @@
+import {Memory} from './memory/memory.ts';
+
+export function cosineDistance(a: number[], b: number[]): number {
+	let dot = 0, normA = 0, normB = 0;
+	for(let i = 0; i < a.length; i++) {
+		dot += a[i] * b[i];
+		normA += a[i] * a[i];
+		normB += b[i] * b[i];
+	}
+	const denom = Math.sqrt(normA) * Math.sqrt(normB);
+	return denom === 0 ? 1 : 1 - dot / denom;
+}
+
+export async function embedMemoryFields(node: Memory, llm: any): Promise<void> {
+	const body = stripHeader(node.content);
+	const [titleE] = await llm.embedding(node.name.split('/').pop() || node.name);
+	const [descE] = await llm.embedding(node.description || '');
+	const bodyChunks = body ? await llm.embedding(body) : [];
+	if(titleE) node.titleEmbedding = titleE.embedding;
+	if(descE) node.embedding = descE.embedding;
+	node.bodyEmbeddings = bodyChunks.map((c: any) => c.embedding).filter(Boolean);
+}
+
+export function euclideanDistance(a: number[], b: number[]): number {
+	let sum = 0;
+	for(let i = 0; i < a.length; i++) {
+		const d = a[i] - b[i];
+		sum += d * d;
+	}
+	return Math.sqrt(sum);
+}
+
+function getWeekStart(date: Date = new Date()): string {
+	const d = new Date(Date.UTC(date.getFullYear(), date.getMonth(), date.getDate()));
+	const day = d.getUTCDay();
+	const diff = day === 0 ? -6 : 1 - day;
+	d.setUTCDate(d.getUTCDate() + diff);
+	return d.toISOString().slice(0, 10);
+}
+
+export function journalDescription(journalName?: string): string {
+	const start = journalName?.split('/').pop() || getWeekStart();
+	const d = new Date(`${start}T00:00:00Z`);
+	d.setUTCDate(d.getUTCDate() + 6);
+	const end = d.toISOString().slice(0, 10);
+	return `Log from ${start} - ${end}`;
+}
+
+function parseFrontmatter(content: string): {fm: Map<string, string>, body: string} {
+	const match = content.match(/^---\n([\s\S]*?)\n---\n?([\s\S]*)$/);
+	if(!match) return {fm: new Map(), body: content};
+	const fm = new Map<string, string>();
+	for(const line of match[1].split('\n')) {
+		const i = line.indexOf(':');
+		if(i === -1) continue;
+		const key = line.slice(0, i).trim();
+		const raw = line.slice(i + 1).trim();
+		let value = raw;
+		try { value = JSON.parse(raw); } catch { }
+		fm.set(key, value);
+	}
+	return {fm, body: match[2]};
+}
+
+export function writeFrontmatter(fm: Map<string, string>, body: string): string {
+	const lines = [...fm.entries()].map(([k, v]) =>
+		`${k}: ${JSON.stringify(String(v).replace(/\s+/g, ' ').trim())}`);
+	return `---\n${lines.join('\n')}\n---\n\n${body.trimStart()}`;
+}
+
+export function stripHeader(content: string): string {
+	return content.replace(/^---[\s\S]*?\n---\n?/, '').trimStart();
+}
+
+export function touchHeader(node: Memory, body: string): string {
+	const {fm} = parseFrontmatter(node.content);
+	fm.set('name', node.name);
+	fm.set('description', (node.name.startsWith('Journal/') ? journalDescription(node.name) : node.description)
+		|| 'Persistent memory document');
+	fm.set('modified', new Date().toISOString());
+	return writeFrontmatter(fm, stripHeader(body));
+}