import assert from "node:assert/strict";
import test from "node:test";
import {
	JavaScriptFuzzyIndex,
	extractCurrentWordPrefix,
	extractExistingPaths,
	extractWords,
	replaceCurrentWordPrefix,
	shouldDelegateToBuiltIn,
} from "../index.ts";

test("JavaScriptFuzzyIndex deduplicates and ranks matching candidates", async () => {
	const index = new JavaScriptFuzzyIndex();
	const added = await index.addCandidatesAsync([
		{ text: "Terminal", source: "session:user" },
		{ text: "terminal", source: "session:assistant" },
		{ text: "template", source: "session:user" },
	]);

	assert.equal(added, 2);
	assert.equal(index.len(), 2);
	assert.deepEqual(
		(await index.queryAsync("te", 8)).map((match) => match.text).sort(),
		["Terminal", "template"].sort(),
	);
});

test("extractCurrentWordPrefix only returns eligible word prefixes", () => {
	assert.equal(extractCurrentWordPrefix("please te"), "te");
	assert.equal(extractCurrentWordPrefix("please t"), undefined);
	assert.equal(extractCurrentWordPrefix("number 123"), undefined);
	assert.equal(extractCurrentWordPrefix("path/to"), "to");
});

test("built-in completion contexts are delegated", () => {
	assert.equal(shouldDelegateToBuiltIn("/hel"), true);
	assert.equal(shouldDelegateToBuiltIn("read @src/"), true);
	assert.equal(shouldDelegateToBuiltIn("open ./index.ts"), true);
	assert.equal(shouldDelegateToBuiltIn("please te"), false);
});

test("replaceCurrentWordPrefix replaces the word around the cursor", () => {
	assert.deepEqual(
		replaceCurrentWordPrefix(["please te now"], 0, 9, "test"),
		{ lines: ["please test now"], cursorLine: 0, cursorCol: 11 },
	);
});

test("extractWords returns bounded word candidates", () => {
	assert.deepEqual(extractWords("Use pi-frizbee and @file_name.", "session:user"), [
		{ text: "Use", source: "session:user" },
		{ text: "pi-frizbee", source: "session:user" },
		{ text: "and", source: "session:user" },
		{ text: "file_name", source: "session:user" },
	]);
});

test("extractExistingPaths keeps only paths that exist", () => {
	const candidates = extractExistingPaths("Read ./index.ts and ./does-not-exist", process.cwd());
	assert.deepEqual(candidates.map((candidate) => candidate.text), [`${process.cwd()}/index.ts`]);
});