import assert from "node:assert/strict";
import { mkdtemp } from "node:fs/promises";
import { tmpdir } from "node:os";
import { join } from "node:path";
import test from "node:test";

import { argumentCompletions } from "../index.ts";
import { addEntry, updateState, type WorktreeEntry } from "../src/state.ts";

function entry(overrides: Partial<WorktreeEntry> = {}): WorktreeEntry {
	return {
		slug: "demo",
		path: "/nonexistent/demo",
		branch: "wt/demo",
		sourcePath: "/nonexistent/source",
		sourceBranch: "main",
		sourceSha: "0".repeat(40),
		createdAt: new Date().toISOString(),
		...overrides,
	};
}

test("first-token completion returns subcommand names", async () => {
	const items = await argumentCompletions("mer");
	assert.ok(items?.some((item) => item.value === "merge"));
});

test("merge flag completions expand to the full argument line", async () => {
	const items = await argumentCompletions("merge --c");
	assert.deepEqual(
		items?.map((item) => ({ value: item.value, label: item.label })),
		[{ value: "merge --continue", label: "--continue" }],
	);
});

test("bare -- after merge offers all four flags as full lines", async () => {
	const items = await argumentCompletions("merge --");
	assert.equal(items?.length, 4);
	for (const item of items ?? []) {
		assert.ok(item.value.startsWith("merge --"), item.value);
	}
});

test("slug completions keep the subcommand in the replacement value", async (t) => {
	const agentDir = await mkdtemp(join(tmpdir(), "pi-worktree-agent-"));
	const previous = process.env.PI_CODING_AGENT_DIR;
	process.env.PI_CODING_AGENT_DIR = agentDir;
	t.after(() => {
		if (previous === undefined) delete process.env.PI_CODING_AGENT_DIR;
		else process.env.PI_CODING_AGENT_DIR = previous;
	});
	await updateState((s) => addEntry(s, entry()));

	const switchItems = await argumentCompletions("switch ");
	const values = switchItems?.map((item) => item.value) ?? [];
	assert.ok(values.includes("switch main"), JSON.stringify(values));
	assert.ok(values.includes("switch demo"), JSON.stringify(values));

	const removeItems = await argumentCompletions("remove d");
	assert.deepEqual(
		removeItems?.map((item) => ({ value: item.value, label: item.label })),
		[{ value: "remove demo", label: "demo" }],
	);
});