1 files changed, 223 insertions, 0 deletions
diff --git a/src/calendar/daily-notes.ts b/src/calendar/daily-notes.ts
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+++ b/src/calendar/daily-notes.ts
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+import { App, TFile, Vault, WorkspaceLeaf } from "obsidian";
+import type { Moment } from "moment";
+
+const DATE_FORMAT = "YYYY-MM-DD";
+
+/**
+ * Computes the vault-relative path for a daily note.
+ * Format: {rootFolder}/{YYYY}/{MM}/{DD}/{YYYY-MM-DD}.md
+ */
+export function getDailyNotePath(date: Moment, rootFolder: string): string {
+	const year = date.format("YYYY");
+	const month = date.format("MM");
+	const day = date.format("DD");
+	const filename = date.format(DATE_FORMAT);
+	return `${rootFolder}/${year}/${month}/${day}/${filename}.md`;
+}
+
+/**
+ * Looks up an existing daily note in the vault for the given date.
+ * Returns null if the file does not exist.
+ */
+export function getDailyNote(
+	app: App,
+	date: Moment,
+	rootFolder: string,
+): TFile | null {
+	const path = getDailyNotePath(date, rootFolder);
+	return app.vault.getFileByPath(path);
+}
+
+/**
+ * Creates a new daily note for the given date.
+ * Creates parent folders ({rootFolder}/{YYYY}/{MM}/{DD}/) if they don't exist.
+ * If a template path is provided and the template file exists, its content is
+ * used with `{{date}}` placeholders replaced by the ISO date string.
+ * Otherwise, a minimal file with date frontmatter is created.
+ */
+export async function createDailyNote(
+	app: App,
+	date: Moment,
+	rootFolder: string,
+	template?: string,
+): Promise<TFile> {
+	const path = getDailyNotePath(date, rootFolder);
+	const dateStr = date.format(DATE_FORMAT);
+
+	// Ensure parent folders exist
+	const folderPath = path.substring(0, path.lastIndexOf("/"));
+	await ensureFolderExists(app.vault, folderPath);
+
+	// Resolve content
+	let content: string;
+	if (template !== undefined && template !== "") {
+		const templateFile = app.vault.getFileByPath(template);
+		if (templateFile !== null) {
+			const raw = await app.vault.cachedRead(templateFile);
+			content = raw.replace(/\{\{date\}\}/g, dateStr);
+		} else {
+			content = defaultDailyNoteContent(dateStr);
+		}
+	} else {
+		content = defaultDailyNoteContent(dateStr);
+	}
+
+	return app.vault.create(path, content);
+}
+
+/**
+ * Opens an existing daily note or creates one first, then opens it.
+ * When `newLeaf` is true, opens in a new tab; otherwise reuses the current leaf.
+ */
+export async function openDailyNote(
+	app: App,
+	date: Moment,
+	rootFolder: string,
+	opts: { newLeaf: boolean },
+	template?: string,
+): Promise<void> {
+	let file = getDailyNote(app, date, rootFolder);
+	if (file === null) {
+		file = await createDailyNote(app, date, rootFolder, template);
+	}
+
+	const leaf: WorkspaceLeaf = app.workspace.getLeaf(opts.newLeaf);
+	await leaf.openFile(file);
+}
+
+/**
+ * Scans the calendar root folder recursively and builds an index of all
+ * daily notes, keyed by their ISO date string ("YYYY-MM-DD").
+ *
+ * Only files that match the expected `{YYYY}/{MM}/{DD}/{YYYY-MM-DD}.md`
+ * structure within the root folder are included.
+ */
+export function indexDailyNotes(
+	app: App,
+	rootFolder: string,
+): Map<string, TFile> {
+	const index = new Map<string, TFile>();
+	const root = app.vault.getFolderByPath(rootFolder);
+	if (root === null) {
+		return index;
+	}
+
+	// Pattern: rootFolder/YYYY/MM/DD/YYYY-MM-DD.md
+	// After stripping rootFolder prefix, remainder is: YYYY/MM/DD/YYYY-MM-DD.md
+	const datePathRegex = /^(\d{4})\/(\d{2})\/(\d{2})\/(\d{4}-\d{2}-\d{2})\.md$/;
+
+	Vault.recurseChildren(root, (abstractFile) => {
+		if (!(abstractFile instanceof TFile)) {
+			return;
+		}
+		if (abstractFile.extension !== "md") {
+			return;
+		}
+
+		const relativePath = abstractFile.path.substring(rootFolder.length + 1);
+		const match = datePathRegex.exec(relativePath);
+		if (match === null) {
+			return;
+		}
+
+		const [, year, month, day, filename] = match;
+		if (
+			year === undefined ||
+			month === undefined ||
+			day === undefined ||
+			filename === undefined
+		) {
+			return;
+		}
+
+		// Verify the folder components match the filename
+		const expectedFilename = `${year}-${month}-${day}`;
+		if (filename !== expectedFilename) {
+			return;
+		}
+
+		// Validate it's a real date
+		const m = window.moment(filename, DATE_FORMAT, true);
+		if (!m.isValid()) {
+			return;
+		}
+
+		index.set(filename, abstractFile);
+	});
+
+	return index;
+}
+
+/**
+ * Given a TFile, determines whether it lives in the daily note folder
+ * structure and extracts the date if so.
+ * Returns null if the file is not a recognized daily note.
+ */
+export function getDateFromDailyNote(
+	file: TFile,
+	rootFolder: string,
+): Moment | null {
+	// File must be under the root folder
+	if (!file.path.startsWith(rootFolder + "/")) {
+		return null;
+	}
+
+	const relativePath = file.path.substring(rootFolder.length + 1);
+	const datePathRegex = /^(\d{4})\/(\d{2})\/(\d{2})\/(\d{4}-\d{2}-\d{2})\.md$/;
+	const match = datePathRegex.exec(relativePath);
+	if (match === null) {
+		return null;
+	}
+
+	const [, year, month, day, filename] = match;
+	if (
+		year === undefined ||
+		month === undefined ||
+		day === undefined ||
+		filename === undefined
+	) {
+		return null;
+	}
+
+	const expectedFilename = `${year}-${month}-${day}`;
+	if (filename !== expectedFilename) {
+		return null;
+	}
+
+	const m = window.moment(filename, DATE_FORMAT, true);
+	if (!m.isValid()) {
+		return null;
+	}
+
+	return m;
+}
+
+// ---------------------------------------------------------------------------
+// Internal helpers
+// ---------------------------------------------------------------------------
+
+/**
+ * Recursively creates folders for the given path if they don't already exist.
+ */
+async function ensureFolderExists(vault: Vault, folderPath: string): Promise<void> {
+	if (vault.getFolderByPath(folderPath) !== null) {
+		return;
+	}
+
+	// Walk from root to deepest folder, creating each segment
+	const segments = folderPath.split("/");
+	let current = "";
+	for (const segment of segments) {
+		current = current === "" ? segment : `${current}/${segment}`;
+		if (vault.getFolderByPath(current) === null) {
+			await vault.createFolder(current);
+		}
+	}
+}
+
+/**
+ * Returns the default content for a new daily note with date frontmatter.
+ */
+function defaultDailyNoteContent(dateStr: string): string {
+	return `---\ndate: ${dateStr}\n---\n`;
+}