import { describe, expect, test, mock, beforeEach, afterAll } from "bun:test";

// Mock child_process BEFORE importing the service
const mockExec = mock((cmd: string, callback: any) => {
    // console.log("Mock Exec Called with:", cmd);
    if (cmd.includes("git rev-parse")) {
        callback(null, { stdout: "main\n" });
    } else if (cmd.includes("git fetch")) {
        callback(null, { stdout: "" });
    } else if (cmd.includes("git log")) {
        callback(null, { stdout: "abcdef Update 1\n123456 Update 2" });
    } else if (cmd.includes("git diff")) {
        callback(null, { stdout: "package.json\nsrc/index.ts" });
    } else if (cmd.includes("bun install")) {
        callback(null, { stdout: "Installed dependencies" });
    } else {
        callback(null, { stdout: "" });
    }
});

mock.module("child_process", () => ({
    exec: mockExec
}));

describe("UpdateService", () => {
    let UpdateService: any;

    beforeEach(async () => {
        mockExec.mockClear();
        // Dynamically import to ensure mock is used
        const module = await import("./update.service");
        UpdateService = module.UpdateService;
    });

    afterAll(() => {
        mock.restore();
    });

    test("checkForUpdates should return updates if log is not empty", async () => {
        const result = await UpdateService.checkForUpdates();
        expect(result.hasUpdates).toBe(true);
        expect(result.branch).toBe("main");
        // Check calls. Note: promisify wraps exec, so expecting specific arguments might be tricky if promisify adds options.
        // But the command string should be there.
        // calls[0] -> rev-parse
        // calls[1] -> fetch
        // calls[2] -> log
        expect(mockExec).toHaveBeenCalledTimes(3);
    });

    test("checkDependencies should detect package.json change", async () => {
        const changed = await UpdateService.checkDependencies("main");
        expect(changed).toBe(true);
        // Note: checking args on mockExec when called via promisify:
        // promisify passes (command, callback) or (command, options, callback).
        // call arguments: [cmd, callback]
        const lastCall = mockExec.mock.lastCall;
        expect(lastCall).toBeDefined();
        if (lastCall) {
            expect(lastCall[0]).toContain("git diff");
        }
    });

    test("installDependencies should run bun install", async () => {
        await UpdateService.installDependencies();
        const lastCall = mockExec.mock.lastCall;
        expect(lastCall).toBeDefined();
        if (lastCall) {
            expect(lastCall[0]).toContain("bun install");
        }
    });
});