import { describe, expect, it } from "vitest";
import { draftIssue, issueTags, lastWeek, readWeek, weekStart } from "../src/week.js";

/** an h-entry as diigo-cache's public page marks it up (by=created) */
const entry = (n: number, created: string, extra = "") =>
	`<li class="h-entry"><time class="dt-published" datetime="${created}">${created}</time> <a class="u-bookmark-of p-name" href="https://ex.example/${n}">bookmark ${n}</a>${extra}<time class="dt-updated" datetime="${created}" hidden></time></li>`;

const page = (entries: string[], next?: string) => `<!doctype html><html><body>
<p>${next ? `<a rel="next" href="${next}">next →</a>` : "<span>next →</span>"}</p>
<ol class="h-feed">
${entries.join("\n")}
</ol></body></html>`;

describe("readWeek", () => {
	it("reads h-entry bookmarks across rel=next pages, oldest first", async () => {
		const asked: string[] = [];
		const pages: Record<string, string> = {
			"/public/dckc-madmode?in=2026-W40&by=created": page(
				[
					entry(
						3,
						"2026-10-03T12:00:00.000Z",
						` <a class="p-category" href="/public/dckc-madmode?q=%23ocap">ocap</a> <a class="p-category" href="/public/dckc-madmode?q=%23weekly">weekly</a><br><small class="p-summary">a week of fragments</small>`,
					),
					entry(2, "2026-10-01T12:00:00.000Z"),
				],
				"/public/dckc-madmode?in=2026-W40&by=created&page=2",
			),
			"/public/dckc-madmode?in=2026-W40&by=created&page=2": page([entry(1, "2026-09-28T12:00:00.000Z")]),
		};
		const get = async (path: string) => {
			asked.push(path);
			const html = pages[path];
			if (!html) throw new Error(`no page ${path}`);
			return html;
		};
		const bookmarks = await readWeek(get, "dckc-madmode", "2026-W40");
		expect(asked).toHaveLength(2);
		expect(bookmarks.map((b) => b.title)).toEqual(["bookmark 1", "bookmark 2", "bookmark 3"]);
		expect(bookmarks[2]).toEqual({
			url: "https://ex.example/3",
			title: "bookmark 3",
			description: "a week of fragments",
			tags: ["ocap", "weekly"],
			published: "2026-10-03T12:00:00.000Z",
		});
	});

	it("doesn't follow a rel=next to another site", async () => {
		const asked: string[] = [];
		const get = async (path: string) => {
			asked.push(path);
			return page([entry(1, "2026-10-01T12:00:00.000Z")], "https://elsewhere.example/public/x");
		};
		await readWeek(get, "dckc-madmode", "2026-W40");
		expect(asked).toHaveLength(1);
	});
});

describe("weeks", () => {
	it("lastWeek is the full ISO week before now", () => {
		expect(lastWeek(new Date("2026-10-09T01:00:00Z"))).toBe("2026-W40");
		// Monday 2026-01-05 starts W02; W01 began Monday 2025-12-29
		expect(lastWeek(new Date("2026-01-05T00:00:00Z"))).toBe("2026-W01");
	});

	it("weekStart is Monday 00:00Z, and refuses a week that doesn't exist", () => {
		expect(weekStart("2026-W40")?.toISOString()).toBe("2026-09-28T00:00:00.000Z");
		expect(weekStart("2025-W01")?.toISOString()).toBe("2024-12-30T00:00:00.000Z");
		expect(weekStart("2025-W53")).toBeUndefined();
		expect(weekStart("2026-40")).toBeUndefined();
	});
});

describe("draftIssue", () => {
	it("drafts title, week, dek, and a body: an intro, then a paragraph per bookmark with tag links", () => {
		const issue = draftIssue("2026-W40", [
			{ url: "https://ex.example/1", title: "one", description: "nice", tags: ["ocap"], published: "2026-09-28T12:00:00.000Z" },
		]);
		expect(issue.title).toBe("Week 2026-W40");
		expect(issue.week).toBe("2026-W40");
		expect(issue.dek).toBe("Sep 28–Oct 4: 1 bookmark. (draft)");
		const [intro, b] = issue.body as { markDefs: { href: string }[]; children: { text: string }[] }[];
		expect(intro.children[0].text).toMatch(/draft/);
		expect(b.markDefs.map((m) => m.href)).toEqual(["https://ex.example/1", "/tag/ocap"]);
		expect(b.children.map((c) => c.text).join("")).toBe("one: nice ocap");
	});

	it("refuses a malformed week", () => {
		expect(() => draftIssue("last week", [])).toThrow(/ISO week/);
	});
});

describe("issueTags", () => {
	it("is every bookmark's tags, once each, in order of first use", () => {
		const b = (tags: string[]) => ({ url: "https://ex.example/", title: "", description: "", tags, published: "" });
		expect(issueTags([b(["governance", "economics"]), b([]), b(["governance", "scaling"])])).toEqual(["governance", "economics", "scaling"]);
	});
});