import { describe, it, expect } from "vitest";
import { extractFileLLM } from "../src/llm/llm-extract.js";
import { writeFileSync, mkdtempSync } from "fs";
import { join } from "path";
import { tmpdir } from "os";
import type { LLMClient } from "../src/llm/llm-client.js";

function createMockClient(response: string): LLMClient {
	return {
		async complete() {
			return response;
		},
	};
}

describe("llm-extract with mock client", () => {
	it("uses LLM client when provided", async () => {
		const dir = mkdtempSync(join(tmpdir(), "pi-map-"));
		const file = join(dir, "test.ts");
		writeFileSync(file, `export const foo = 1;`);

		const mockClient = createMockClient(
			"PURPOSE: Test file\nDEPS: none\nCONCEPTS: testing",
		);

		const result = await extractFileLLM(file, mockClient, tmpdir());
		expect(result.purpose).toBe("Test file");
		expect(result.deps).toEqual([]);
		expect(result.concepts).toContain("testing");
	});

	it("throws without LLM client", async () => {
		const dir = mkdtempSync(join(tmpdir(), "pi-map-"));
		const file = join(dir, "test.ts");
		writeFileSync(file, `export const foo = 1;`);

		await expect(extractFileLLM(file)).rejects.toThrow("No LLM client configured");
	});

	it("skips large files", async () => {
		const dir = mkdtempSync(join(tmpdir(), "pi-map-"));
		const file = join(dir, "big.ts");
		writeFileSync(file, "x".repeat(600 * 1024));

		const mockClient = createMockClient(
			"PURPOSE: Should not call\nDEPS: none\nCONCEPTS: none",
		);

		const result = await extractFileLLM(file, mockClient);
		expect(result.purpose).toBe("Large file");
	});

	it("skips binary files", async () => {
		const dir = mkdtempSync(join(tmpdir(), "pi-map-"));
		const file = join(dir, "image.png");
		// Write some binary-looking content with null bytes
		const buf = Buffer.from([0x89, 0x50, 0x4e, 0x47, 0x0d, 0x0a, 0x1a, 0x0a]);
		writeFileSync(file, buf);

		const mockClient = createMockClient(
			"PURPOSE: Should not call\nDEPS: none\nCONCEPTS: none",
		);

		const result = await extractFileLLM(file, mockClient);
		expect(result.purpose).toBe("Binary file");
	});

	it("parses response with deps and concepts", async () => {
		const dir = mkdtempSync(join(tmpdir(), "pi-map-"));
		const file = join(dir, "test.ts");
		writeFileSync(file, `import { foo } from "bar";\nexport const x = 1;`);

		const mockClient = createMockClient(
			"PURPOSE: Config module\nDEPS: bar, baz\nCONCEPTS: constants, config",
		);

		const result = await extractFileLLM(file, mockClient, tmpdir());
		expect(result.purpose).toBe("Config module");
		expect(result.deps).toEqual(["bar", "baz"]);
		expect(result.concepts).toEqual(["constants", "config"]);
	});
});