// Tests for util.ts
// Pure unit tests with filesystem

import assert from "node:assert/strict";
import { mkdir, rm, writeFile } from "node:fs/promises";
import { join } from "node:path";
import { after, before, describe, it } from "node:test";
import { loadFile } from "./util";

describe("util", () => {
    const testDir = join(import.meta.dirname, ".test-util-tmp");

    before(async () => {
        await mkdir(testDir, { recursive: true });
    });

    after(async () => {
        await rm(testDir, { recursive: true, force: true });
    });

    describe("loadFile", () => {
        it("loads file contents as string", async () => {
            const testFile = join(testDir, "test.txt");
            await writeFile(testFile, "hello world");

            const content = await loadFile(testFile);
            assert.equal(content, "hello world");
        });

        it("handles utf-8 content", async () => {
            const testFile = join(testDir, "utf8.txt");
            await writeFile(testFile, "hello \u{1F511} world");

            const content = await loadFile(testFile);
            assert.equal(content, "hello \u{1F511} world");
        });

        it("handles empty file", async () => {
            const testFile = join(testDir, "empty.txt");
            await writeFile(testFile, "");

            const content = await loadFile(testFile);
            assert.equal(content, "");
        });

        it("handles multiline content", async () => {
            const testFile = join(testDir, "multiline.txt");
            await writeFile(testFile, "line1\nline2\nline3");

            const content = await loadFile(testFile);
            assert.equal(content, "line1\nline2\nline3");
        });

        it("throws for nonexistent file", async () => {
            await assert.rejects(
                loadFile(join(testDir, "nonexistent.txt")),
                /ENOENT/,
            );
        });
    });
});