/**
 * Authentication Helper for UI Tests
 * Handles login and registration for Puppeteer tests
 */

const crypto = require('crypto');

/**
 * Timing utility for detailed performance logging
 */
class Timer {
    constructor(label) {
        this.label = label;
        this.startTime = Date.now();
        this.laps = [];
    }

    lap(description) {
        const now = Date.now();
        const elapsed = now - this.startTime;
        const lapTime = this.laps.length > 0
            ? now - this.laps[this.laps.length - 1].timestamp
            : elapsed;
        this.laps.push({ description, elapsed, lapTime, timestamp: now });
        return elapsed;
    }

    elapsed() {
        return Date.now() - this.startTime;
    }

    summary() {
        const total = this.elapsed();
        console.log(`  ⏱️  [${this.label}] TOTAL: ${total}ms (${(total/1000).toFixed(1)}s)`);
        return total;
    }
}

const DEFAULT_TEST_USER = {
    username: 'testuser',
    password: 'T3st!Secure#2024$LDR'
};

// CI pre-created test user (created in GitHub workflow's "Initialize database" step)
// This user is created BEFORE tests run, so no slow registration needed
const CI_TEST_USER = {
    username: 'test_admin',
    password: 'testpass123'
};

// Configuration constants - single source of truth for auth helper settings
const AUTH_CONFIG = {
    // Route paths
    paths: {
        login: '/auth/login',
        register: '/auth/register',
        logout: '/auth/logout'
    },
    // Timeouts (ms) - CI has longer timeouts due to:
    // 1. Slower CI runners with shared resources
    // 2. Registration creates encrypted SQLCipher database
    // 3. Key derivation from password is CPU intensive
    // 4. Creating 58 database tables takes time
    // 5. Importing 500+ settings from JSON files
    // Note: If registration takes >2min, something is likely wrong
    timeouts: {
        navigation: process.env.CI ? 60000 : 30000,       // 1 min in CI (reduced from 3 min)
        formSelector: process.env.CI ? 30000 : 5000,      // 30s in CI (reduced from 1 min)
        submitNavigation: process.env.CI ? 60000 : 60000,   // 1 min in CI (fast KDF makes 2 min unnecessary)
        urlCheck: process.env.CI ? 10000 : 5000,          // 10s in CI (reduced from 30s)
        errorCheck: process.env.CI ? 5000 : 2000,         // 5s in CI (reduced from 15s)
        logout: process.env.CI ? 30000 : 10000            // 30s in CI (reduced from 1 min)
    },
    // Delays (ms)
    delays: {
        retryNavigation: process.env.CI ? 2000 : 1000,    // 2s between retries in CI
        afterRegistration: process.env.CI ? 5000 : 3000,  // 5s after registration in CI
        beforeRetry: process.env.CI ? 5000 : 5000,        // 5s before retry in CI
        afterLogout: process.env.CI ? 2000 : 1000         // 2s after logout in CI
    },
    // CI-specific settings
    ci: {
        waitUntil: 'domcontentloaded',
        maxLoginAttempts: 10,        // Reduced from 15 - fail faster
        maxNavigationRetries: 3      // Reduced from 5 - fail faster
    }
};

// Generate random username for each test to avoid conflicts
function generateRandomUsername() {
    const timestamp = Date.now();
    let random;
    // Use rejection sampling to avoid bias
    const maxValue = 4294967295; // Max value for 32-bit unsigned int
    const limit = maxValue - (maxValue % 1000); // Largest multiple of 1000 that fits

    do {
        random = crypto.randomBytes(4).readUInt32BE(0);
    } while (random >= limit); // Reject values that would cause bias

    random %= 1000;
    return `testuser_${timestamp}_${random}`;
}

class AuthHelper {
    constructor(page, baseUrl = 'http://127.0.0.1:5000') {
        this.page = page;
        this.baseUrl = baseUrl;
        this.isCI = !!process.env.CI;
    }

    /**
     * Get the current page reference.
     * The page may have been replaced if a detached frame error was recovered.
     * Tests should call this after ensureAuthenticated() to get the working page.
     */
    getPage() {
        return this.page;
    }

    /**
     * Helper method for delays
     */
    async _delay(ms) {
        return new Promise(resolve => setTimeout(resolve, ms));
    }

    /**
     * Wait for server to become responsive
     * Uses Node.js http.get instead of page.evaluate to avoid Puppeteer's
     * protocolTimeout (600s) when the page is in a bad state after navigation failure.
     */
    async _waitForServerReady(maxWaitMs = 120000, checkIntervalMs = 5000) {
        const http = require('http');
        const startTime = Date.now();

        while (Date.now() - startTime < maxWaitMs) {
            try {
                const ok = await new Promise((resolve) => {
                    const req = http.get(this.baseUrl, { timeout: 10000 }, (res) => {
                        resolve(res.statusCode >= 200 && res.statusCode < 400);
                        res.resume(); // drain the response
                    });
                    req.on('error', () => resolve(false));
                    req.on('timeout', () => { req.destroy(); resolve(false); });
                });

                if (ok) {
                    return true;
                }
            } catch {
                // ignore - will retry
            }

            await this._delay(checkIntervalMs);
        }

        console.log(`  Server did not become ready within ${maxWaitMs/1000}s`);
        return false;
    }

    /**
     * Navigate to an auth page with CI-aware retry logic
     * @param {string} path - The path to navigate to (e.g., AUTH_CONFIG.paths.login)
     * @param {string} expectedPathSegment - Path segment to verify arrival (e.g., '/auth/login')
     * @returns {string} The URL we arrived at
     */
    async _navigateToAuthPage(path, expectedPathSegment) {
        const timer = new Timer(`nav:${path}`);
        const targetUrl = `${this.baseUrl}${path}`;
        const waitUntil = this.isCI ? AUTH_CONFIG.ci.waitUntil : 'networkidle2';
        const maxRetries = this.isCI ? AUTH_CONFIG.ci.maxNavigationRetries : 1;
        const timeout = AUTH_CONFIG.timeouts.navigation;

        let arrivedUrl = '';
        let lastError = null;

        for (let attempt = 1; attempt <= maxRetries; attempt++) {
            try {
                timer.lap(`attempt ${attempt} start`);
                await this.page.goto(targetUrl, {
                    waitUntil,
                    timeout
                });
                timer.lap(`attempt ${attempt} navigation complete`);

                arrivedUrl = this.page.url();

                // Check if we arrived at expected page
                if (arrivedUrl.includes(expectedPathSegment)) {
                    return arrivedUrl;
                }

                // If redirected somewhere else (like home when logged in), that's also OK
                if (!arrivedUrl.includes('/auth/')) {
                    return arrivedUrl;
                }

                // If we didn't get where we wanted, retry
                if (attempt < maxRetries) {
                    await this._delay(AUTH_CONFIG.delays.retryNavigation);
                }
            } catch (navError) {
                lastError = navError;

                // If the frame is detached, create a fresh page and retry
                if (navError.message.includes('detached') || navError.message.includes('destroyed')) {
                    try {
                        const browser = this.page.browser();
                        const newPage = await browser.newPage();
                        try { await this.page.close(); } catch { /* already broken */ }
                        this.page = newPage;
                    } catch {
                        // Could not create fresh page
                    }
                }

                if (attempt < maxRetries) {
                    await this._delay(AUTH_CONFIG.delays.retryNavigation);
                }
            }
        }

        // If we got a URL but it wasn't what we expected, return it anyway
        if (arrivedUrl) {
            return arrivedUrl;
        }

        // If we never got a URL, throw the last error
        throw lastError || new Error(`Failed to navigate to ${path} after ${maxRetries} attempts`);
    }

    /**
     * Check if user is logged in by looking for logout button or username
     */
    async isLoggedIn() {
        try {
            const url = this.page.url();

            if (url.includes(AUTH_CONFIG.paths.login)) {
                return false;
            }

            // Check for logout button/link
            const logoutSelectors = [
                'a.logout-btn',
                '#logout-form',
                'form[action="/auth/logout"]',
                'a[onclick*="logout"]'
            ];

            for (const selector of logoutSelectors) {
                try {
                    const element = await this.page.$(selector);
                    if (element) {
                        return true;
                    }
                } catch {
                    // Some selectors might not be valid, continue
                }
            }

            // Check if we can access protected pages
            const currentUrl = this.page.url();
            if (currentUrl.includes('/settings') || currentUrl.includes('/metrics') || currentUrl.includes('/history')) {
                return true;
            }

            // If we're on the home page, check for research form
            const researchForm = await this.page.$('form[action*="research"], #query, button[type="submit"]');
            if (researchForm) {
                return true;
            }

            return false;
        } catch {
            return false;
        }
    }

    /**
     * Login with existing user credentials
     */
    async login(username = DEFAULT_TEST_USER.username, password = DEFAULT_TEST_USER.password) {
        const timer = new Timer('login');
        console.log(`🔐 Attempting login as ${username}...`);

        // Check if already logged in
        if (await this.isLoggedIn()) {
            console.log('✅ Already logged in');
            timer.summary();
            return true;
        }
        timer.lap('checked login status');

        // Always navigate to login page to ensure fresh CSRF token
        // (After logout, the page may have a stale token from the previous session)
        await this._navigateToAuthPage(AUTH_CONFIG.paths.login, AUTH_CONFIG.paths.login);
        timer.lap('navigated to login page');

        // Wait for login form
        await this.page.waitForSelector('input[name="username"]', { timeout: AUTH_CONFIG.timeouts.formSelector });
        timer.lap('login form ready');

        // Clear fields first to ensure clean state
        await this.page.$eval('input[name="username"]', el => { el.value = ''; });
        await this.page.$eval('input[name="password"]', el => { el.value = ''; });

        // Type credentials
        await this.page.type('input[name="username"]', username);
        await this.page.type('input[name="password"]', password);
        timer.lap('credentials filled');

        // Listen to page errors
        this.page.on('pageerror', error => console.log('  Page error:', error.message));

        try {
            // In CI, use a simpler and faster approach
            // NOTE: Previous implementation used a polling loop that called page.evaluate()
            // 30 times with 10s timeouts each. When the page was navigating, evaluate()
            // would hang, causing 5+ minute delays ("URL check timeout" x30).
            // This simpler Promise.all approach completes in seconds.
            if (this.isCI) {
                timer.lap('starting CI login');

                // Use Promise.all with waitForNavigation - the standard Puppeteer approach
                // This is more reliable than polling page.evaluate() which hangs during navigation
                try {
                    await Promise.all([
                        this.page.waitForNavigation({
                            waitUntil: 'domcontentloaded',
                            timeout: AUTH_CONFIG.timeouts.navigation  // 60s in CI, 30s locally
                        }),
                        this.page.click('button[type="submit"]')
                    ]);
                    timer.lap('navigation complete after submit');
                } catch (navError) {
                    timer.lap(`navigation error: ${navError.message.substring(0, 50)}`);

                    // Check if we actually succeeded despite the error
                    const currentUrl = this.page.url();

                    if (!currentUrl.includes(AUTH_CONFIG.paths.login)) {
                        // Actually redirected successfully
                    } else {
                        // Check for session cookie - login may have worked
                        const cookies = await this.page.cookies();
                        const sessionCookie = cookies.find(c => c.name === 'session');
                        if (sessionCookie) {
                            // NOTE: Using configured navigation timeout instead of hardcoded 15s
                            // because CI runners can be slow and 15s often isn't enough
                            await this.page.goto(this.baseUrl, {
                                waitUntil: 'domcontentloaded',
                                timeout: AUTH_CONFIG.timeouts.navigation  // 60s in CI
                            });
                            timer.lap('navigated to home via cookie');
                        } else {
                            // Check for error message
                            const errorEl = await this.page.$('.alert-danger, .error-message');
                            if (errorEl) {
                                const errorText = await this.page.evaluate(el => el.textContent.trim(), errorEl);
                                throw new Error(`Login failed: ${errorText}`);
                            }
                            throw new Error('Login failed - no redirect, no cookie');
                        }
                    }
                }

                timer.lap('CI login complete');
            } else {
                // Non-CI logic - use domcontentloaded instead of networkidle2 to avoid WebSocket/polling timeouts
                await Promise.all([
                    this.page.waitForNavigation({
                        waitUntil: 'domcontentloaded',
                        timeout: AUTH_CONFIG.timeouts.submitNavigation
                    }),
                    this.page.click('button[type="submit"]')
                ]);
            }
        } catch (navError) {
            timer.lap(`navigation error: ${navError.message.substring(0, 40)}`);
            timer.summary();
            throw navError;
        }

        // Check if login was successful
        const finalUrl = this.page.url();

        if (finalUrl.includes(AUTH_CONFIG.paths.login)) {
            // Still on login page - check for error
            const error = await this.page.$('.alert-danger, .error-message, .alert');
            if (error) {
                const errorText = await this.page.evaluate(el => el.textContent, error);
                timer.summary();
                throw new Error(`Login failed: ${errorText.trim()}`);
            }

            timer.summary();
            throw new Error('Login failed - still on login page');
        }

        timer.summary();
        console.log('✅ Login successful');
        return true;
    }

    /**
     * Register a new user
     */
    async register(username = DEFAULT_TEST_USER.username, password = DEFAULT_TEST_USER.password) {
        const timer = new Timer('register');
        console.log(`📝 Attempting registration for ${username}...`);
        // Navigate to registration page using the helper
        const arrivedUrl = await this._navigateToAuthPage(AUTH_CONFIG.paths.register, AUTH_CONFIG.paths.register);
        timer.lap('navigation complete');

        // If redirected to login, registration might be disabled
        if (arrivedUrl.includes(AUTH_CONFIG.paths.login)) {
            throw new Error('Registration page redirected to login - registrations may be disabled');
        }

        // Wait for registration form
        await this.page.waitForSelector('input[name="username"]', { timeout: AUTH_CONFIG.timeouts.formSelector });
        timer.lap('form ready');
        await this.page.type('input[name="username"]', username);
        await this.page.type('input[name="password"]', password);
        await this.page.type('input[name="confirm_password"]', password);
        timer.lap('form filled');

        // Check acknowledgment checkbox if present
        const acknowledgeCheckbox = await this.page.$('input[name="acknowledge"]');
        if (acknowledgeCheckbox) {
            await this.page.click('input[name="acknowledge"]');
            timer.lap('checkbox clicked');
        }

        // Submit form - use CI-specific approach with waitForNavigation + retries
        if (this.isCI) {
            // In CI, registration can take 2+ minutes due to encrypted DB creation.
            // The page.evaluate() approach doesn't work because the page is unresponsive
            // during server processing. Instead, we use waitForNavigation with retries.

            let registrationSucceeded = false;

            try {
                await Promise.all([
                    this.page.waitForNavigation({
                        waitUntil: 'domcontentloaded',
                        timeout: AUTH_CONFIG.timeouts.submitNavigation  // 5 minutes
                    }),
                    this.page.click('button[type="submit"]')
                ]);

                const currentUrl = this.page.url();

                if (!currentUrl.includes(AUTH_CONFIG.paths.register)) {
                    registrationSucceeded = true;
                }
            } catch (navError) {
                // Handle frame detachment (page was replaced)
                if (navError.message.includes('detached') || navError.message.includes('destroyed')) {
                    await this._delay(AUTH_CONFIG.delays.afterRegistration);

                    // The current page's frame is broken - get a fresh page from the browser
                    try {
                        const browser = this.page.browser();
                        const newPage = await browser.newPage();
                        try { await this.page.close(); } catch { /* already broken */ }
                        this.page = newPage;

                        await this.page.goto(this.baseUrl, {
                            waitUntil: AUTH_CONFIG.ci.waitUntil,
                            timeout: AUTH_CONFIG.timeouts.formSelector
                        });
                        registrationSucceeded = true;
                    } catch {
                        // Could not navigate to home after frame detachment
                    }
                }
                // For timeout errors, fall through to session verification below
            }

            // If navigation didn't clearly succeed, verify via session with retries
            if (!registrationSucceeded) {
                // Ensure we have a working page (may have been replaced above)
                try {
                    await this.page.url();
                } catch {
                    const browser = this.page.browser();
                    try { await this.page.close(); } catch { /* already broken */ }
                    this.page = await browser.newPage();
                }

                // Wait for server to become ready (might be still processing)
                // In CI, registration can take 2+ minutes due to encrypted DB creation
                const serverReady = await this._waitForServerReady(180000, 10000);  // 3 min max, check every 10s

                if (serverReady) {
                    // Try to navigate and verify session
                    for (let retryAttempt = 1; retryAttempt <= 3; retryAttempt++) {
                        try {
                            await this.page.goto(this.baseUrl, {
                                waitUntil: AUTH_CONFIG.ci.waitUntil,
                                timeout: AUTH_CONFIG.timeouts.formSelector
                            });

                            const homeUrl = this.page.url();

                            if (!homeUrl.includes('/auth/login') && !homeUrl.includes('/auth/register')) {
                                const logoutBtn = await this.page.$('#logout-form, a[href*="logout"], .logout');
                                if (logoutBtn) {
                                    registrationSucceeded = true;
                                    break;
                                }
                            }
                        } catch {
                            if (retryAttempt < 3) {
                                await this._delay(10000);  // Wait 10s before retry
                            }
                        }
                    }
                }
            }

            if (registrationSucceeded) {
                console.log('✅ Registration successful');
                return true;
            }

            // Check if still on registration page with an error
            const currentUrl = this.page.url();
            if (currentUrl.includes(AUTH_CONFIG.paths.register)) {
                try {
                    const error = await this.page.$('.alert-danger:not(.alert-warning), .error-message');
                    if (error) {
                        const errorText = await this.page.evaluate(el => el.textContent, error);
                        if (errorText.includes('already exists')) {
                            console.log('⚠️  User already exists, attempting login instead');
                            return await this.login(username, password);
                        }
                        throw new Error(`Registration failed: ${errorText.trim()}`);
                    }
                } catch (e) {
                    if (e.message.includes('Registration failed')) throw e;
                    // Ignore error checking errors
                }
            }

            throw new Error('Registration failed - could not verify success');
        }

        // Non-CI logic - use waitForNavigation
        try {
            await Promise.all([
                this.page.waitForNavigation({
                    waitUntil: 'domcontentloaded',
                    timeout: AUTH_CONFIG.timeouts.submitNavigation
                }),
                this.page.click('button[type="submit"]')
            ]);
            timer.lap('form submitted + navigation complete');
        } catch (navError) {
            timer.lap(`submit error: ${navError.message.substring(0, 50)}`);

            // Handle frame detachment errors
            if (navError.message.includes('detached')) {
                // Wait for registration to complete server-side
                await this._delay(AUTH_CONFIG.delays.afterRegistration);
                timer.lap('post-registration delay complete');

                // The current page's frame is broken - get a fresh page
                try {
                    const browser = this.page.browser();
                    const newPage = await browser.newPage();
                    try { await this.page.close(); } catch { /* already broken */ }
                    this.page = newPage;

                    await this.page.goto(this.baseUrl, {
                        waitUntil: 'domcontentloaded',
                        timeout: AUTH_CONFIG.timeouts.formSelector
                    });
                    timer.lap('navigated to home');
                } catch {
                    // Could not navigate after registration
                }

                timer.summary();
                console.log('✅ Registration completed');
                return true;
            }
            timer.summary();
            throw navError;
        }

        // Check if registration was successful
        const currentUrl = this.page.url();
        timer.lap('checking result URL');
        if (currentUrl.includes(AUTH_CONFIG.paths.register)) {
            // Still on registration page - check for actual errors (not warnings)
            const error = await this.page.$('.alert-danger:not(.alert-warning), .error-message');
            if (error) {
                const errorText = await this.page.evaluate(el => el.textContent, error);
                if (errorText.includes('already exists')) {
                    console.log('⚠️  User already exists, attempting login instead');
                    timer.summary();
                    return await this.login(username, password);
                }
                timer.summary();
                throw new Error(`Registration failed: ${errorText}`);
            }

            // Check for security warnings (these are not errors)
            const warning = await this.page.$('.alert-warning');
            if (warning) {
                const warningText = await this.page.evaluate(el => el.textContent, warning);
                console.log('⚠️  Security warning:', warningText.trim().replace(/\s+/g, ' '));
            }

            timer.summary();
            throw new Error('Registration failed - still on registration page');
        }

        timer.summary();
        console.log('✅ Registration successful');
        return true;
    }

    /**
     * Ensure user is authenticated - register if needed, then login
     * In CI mode, first tries the pre-created CI test user for speed
     */
    async ensureAuthenticated(username = null, password = DEFAULT_TEST_USER.password, retries = null) {
        const timer = new Timer('ensureAuthenticated');

        // Use more retries in CI environment
        if (retries === null) {
            retries = this.isCI ? 2 : 2;
        }

        // Check if already logged in
        try {
            if (await this.isLoggedIn()) {
                console.log('✅ Already logged in');
                timer.summary();
                return true;
            }
        } catch (checkError) {
            console.log(`⚠️  Could not check login status: ${checkError.message}`);
            // Continue with authentication attempt
        }
        timer.lap('login status checked');

        // In CI, try the pre-created CI test user first (much faster than registration!)
        // If CI login fails, fall back to registration (slower but reliable).
        // This allows incremental migration - workflows with init_test_database.py
        // get the speed benefit, while others still work via registration fallback.
        if (this.isCI) {
            try {
                console.log('🔐 Trying CI test user login...');
                await this.login(CI_TEST_USER.username, CI_TEST_USER.password);
                console.log('✅ Logged in with CI test user');
                timer.summary();
                return true;
            } catch (ciLoginError) {
                console.log(`⚠️  CI test user login failed: ${ciLoginError.message.substring(0, 80)}`);
                // Fall back to registration (slower but reliable)
            }
        }

        // ---------------------------------------------------------------
        // GOTCHA — fresh-user fallback can masquerade as a server FD/DB leak.
        //
        // When the CI test-user login above fails, every test falls back to
        // registering a BRAND-NEW user (generateRandomUsername() below). The
        // most common cause locally is the shared `test_admin` getting
        // failed-login *lockout-locked* after several iterations — once that
        // happens, each test in a shard registers its own `testuser_<ts>`.
        //
        // Each fresh user gets its own per-user encrypted DB + SQLAlchemy
        // engine on the server. Those engines are only disposed by logout or
        // the periodic connection-cleanup sweep (~300s; see
        // docs/developing/resource-cleanup.md and ADR-0004), so within a
        // single sub-300s shard run they accumulate. The server's open
        // file-descriptor count to encrypted_databases/*.db(-wal/-shm) then
        // climbs ~linearly across tests — which looks EXACTLY like a per-user
        // DB connection leak but is purely this test artifact.
        //
        // In real CI a single working `test_admin` is reused, so there is one
        // engine and FDs stay bounded by the pool cap (pool_size 20 +
        // max_overflow 40 = 60). Before chasing a "chat shards leak / hang",
        // confirm you are NOT in this fallback: grep the server log for many
        // distinct `testuser_<ts>` opens. The chat-shard CI failures
        // themselves are runner contention (60s navigation timeouts under a
        // heavily-loaded Docker runner), not a server-side connection leak —
        // both chat shards pass locally in faithful CI mode with bounded FDs.
        // ---------------------------------------------------------------

        // Generate random username if not provided
        if (!username) {
            username = generateRandomUsername();
        }

        let lastError;
        for (let attempt = 1; attempt <= retries; attempt++) {
            try {
                return await this.register(username, password);
            } catch (registerError) {
                // If user already exists, try login
                if (registerError.message.includes('already exists') ||
                    registerError.message.includes('still on registration page')) {
                    try {
                        return await this.login(username, password);
                    } catch (loginError) {
                        lastError = loginError;
                    }
                } else {
                    lastError = registerError;
                }

                console.log(`🔄 Auth attempt ${attempt}/${retries} failed: ${lastError.message.substring(0, 80)}`);

                // If timeout or network error, wait and retry
                if (attempt < retries &&
                    (lastError.message.includes('timeout') ||
                     lastError.message.includes('net::') ||
                     lastError.message.includes('Navigation'))) {
                    await this._delay(AUTH_CONFIG.delays.beforeRetry);
                    continue;
                }

                if (attempt === retries) {
                    console.log(`❌ Auth failed after ${retries} attempts. Last error: ${lastError.message}`);
                    timer.summary();
                    throw lastError;
                }
            }
        }

        timer.summary();
        throw lastError || new Error('Failed to authenticate after retries');
    }

    /**
     * Wrapper around ensureAuthenticated() with a timeout guard.
     * Prevents auth from hanging indefinitely in CI when the server is unresponsive.
     * Default: 120s CI, 30s local.
     */
    async ensureAuthenticatedWithTimeout(username = null, password = DEFAULT_TEST_USER.password, timeoutMs = null) {
        if (timeoutMs === null) {
            timeoutMs = this.isCI ? 120000 : 30000;
        }
        return new Promise((resolve, reject) => {
            const timer = setTimeout(() => {
                console.log(`⏱️  Auth timeout after ${timeoutMs / 1000}s — ensureAuthenticated did not complete`);
                reject(new Error(`Auth timeout: did not complete within ${timeoutMs / 1000}s`));
            }, timeoutMs);
            this.ensureAuthenticated(username, password).then(
                (val) => { clearTimeout(timer); resolve(val); },
                (err) => { clearTimeout(timer); reject(err); }
            );
        });
    }

    /**
     * Logout the current user
     */
    async logout() {
        console.log('🚪 Logging out...');

        try {
            // Try to find and submit the logout form directly (more reliable than clicking link)
            const logoutForm = await this.page.$('#logout-form');
            if (logoutForm) {
                await Promise.all([
                    this.page.waitForNavigation({
                        waitUntil: 'networkidle2',
                        timeout: AUTH_CONFIG.timeouts.logout
                    }).catch(() => {}),
                    this.page.evaluate(() => {
                        document.getElementById('logout-form').submit();
                    })
                ]);
            } else {
                const logoutLink = await this.page.$('a.logout-btn');
                if (logoutLink) {
                    await Promise.all([
                        this.page.waitForNavigation({
                            waitUntil: 'networkidle2',
                            timeout: AUTH_CONFIG.timeouts.logout
                        }).catch(() => {}),
                        this.page.click('a.logout-btn')
                    ]);
                } else {
                    // Last resort: navigate directly to logout URL
                    await this.page.goto(`${this.page.url().split('/').slice(0, 3).join('/')}${AUTH_CONFIG.paths.logout}`, {
                        waitUntil: 'networkidle2',
                        timeout: AUTH_CONFIG.timeouts.logout
                    });
                }
            }

            // Give it a moment for any redirects
            await this._delay(AUTH_CONFIG.delays.afterLogout);

            const currentUrl = this.page.url();
            const loginForm = await this.page.$('form[action*="login"], input[name="username"]');
            if (loginForm || currentUrl.includes(AUTH_CONFIG.paths.login)) {
                console.log('✅ Logged out successfully');
            } else {
                // Double-check by trying to access a protected page
                await this.page.goto(`${this.page.url().split('/').slice(0, 3).join('/')}/settings/`, {
                    waitUntil: 'networkidle2',
                    timeout: AUTH_CONFIG.timeouts.formSelector
                }).catch(() => {});

                const finalUrl = this.page.url();
                if (!finalUrl.includes(AUTH_CONFIG.paths.login)) {
                    console.log(`Warning: May not be fully logged out. Current URL: ${finalUrl}`);
                } else {
                    console.log('✅ Logged out successfully');
                }
            }
        } catch (error) {
            console.log(`⚠️ Logout error: ${error.message}`);
        }
    }
}

/**
 * Safe click utility - waits for element to be visible and clickable
 * Use this instead of direct element.click() to avoid "not clickable" errors
 *
 * @param {Page} page - Puppeteer page object
 * @param {string|ElementHandle} selectorOrElement - CSS selector or element handle
 * @param {Object} options - Options for the click
 * @param {number} options.timeout - Max time to wait for element (default: 10000ms)
 * @param {boolean} options.scrollIntoView - Scroll element into view before clicking (default: true)
 * @returns {Promise<boolean>} - True if click succeeded
 */
async function safeClick(page, selectorOrElement, options = {}) {
    const timeout = options.timeout || (process.env.CI ? 15000 : 10000);
    const scrollIntoView = options.scrollIntoView !== false;

    let element;

    // Get the element handle
    if (typeof selectorOrElement === 'string') {
        try {
            await page.waitForSelector(selectorOrElement, {
                visible: true,
                timeout
            });
            element = await page.$(selectorOrElement);
        } catch {
            console.log(`safeClick: Element not found or not visible: ${selectorOrElement}`);
            return false;
        }
    } else {
        element = selectorOrElement;
    }

    if (!element) {
        console.log('safeClick: No element to click');
        return false;
    }

    try {
        // Scroll element into view if needed
        if (scrollIntoView) {
            await page.evaluate(el => {
                el.scrollIntoView({ behavior: 'instant', block: 'center', inline: 'center' });
            }, element);
            // Small delay after scrolling
            await new Promise(r => setTimeout(r, 100));
        }

        // Wait for element to be in a clickable state
        await page.evaluate(el => {
            return new Promise((resolve, reject) => {
                const checkClickable = () => {
                    const rect = el.getBoundingClientRect();
                    const isVisible = rect.width > 0 && rect.height > 0;
                    const isInViewport = rect.top >= 0 && rect.left >= 0;
                    const style = window.getComputedStyle(el);
                    const notHidden = style.visibility !== 'hidden' && style.display !== 'none';

                    if (isVisible && notHidden) {
                        resolve(true);
                    } else {
                        reject(new Error('Element not clickable'));
                    }
                };

                // Check immediately and after a short delay
                setTimeout(checkClickable, 50);
            });
        }, element);

        // Perform the click
        await element.click();
        return true;

    } catch (clickError) {
        console.log(`safeClick: Click failed - ${clickError.message}`);

        // Fallback: try clicking via JavaScript
        try {
            await page.evaluate(el => el.click(), element);
            console.log('safeClick: Fallback JS click succeeded');
            return true;
        } catch (jsClickError) {
            console.log(`safeClick: JS click also failed - ${jsClickError.message}`);
            return false;
        }
    }
}

/**
 * Wait for a selector to be present and visually stable.
 *
 * Use this instead of `await delay(N)` after an action that triggers UI to
 * settle (e.g., a button click that reveals a panel, a typed input that
 * triggers debounced validation). It resolves as soon as the element's
 * bounding box hasn't moved for `idleMs` of `requestAnimationFrame` ticks,
 * up to a 3s in-page budget.
 *
 * DO NOT replace `delay()` calls that intentionally exercise wall-clock
 * behavior (e.g., a 10s timer the app is supposed to respect) — those tests
 * need real elapsed time, not a settle wait.
 *
 * @param {Page} page - Puppeteer page object
 * @param {string} selector - CSS selector to wait for
 * @param {Object} [options]
 * @param {number} [options.timeout=5000]  Max time to wait for the selector to appear
 * @param {number} [options.idleMs=200]    Final settle pause after layout stabilizes
 */
async function waitForStable(page, selector, options = {}) {
    const timeout = options.timeout || 5000;
    const idleMs = options.idleMs ?? 200;

    await page.waitForSelector(selector, { visible: true, timeout });
    await page.evaluate(async (sel, idle) => {
        const el = document.querySelector(sel);
        if (!el) return;
        let last = el.getBoundingClientRect();
        const start = Date.now();
        // Bounded in-page poll: returns as soon as the layout settles, or after
        // 3s if the element keeps moving (caller can extend via outer logic).
        while (Date.now() - start < 3000) {
            await new Promise((r) => requestAnimationFrame(r));
            const now = el.getBoundingClientRect();
            if (
                now.x === last.x &&
                now.y === last.y &&
                now.width === last.width &&
                now.height === last.height
            ) {
                await new Promise((r) => setTimeout(r, idle));
                return;
            }
            last = now;
        }
    }, selector, idleMs);
}

module.exports = AuthHelper;
module.exports.safeClick = safeClick;
module.exports.waitForStable = waitForStable;
module.exports.AUTH_CONFIG = AUTH_CONFIG;
module.exports.Timer = Timer;
module.exports.CI_TEST_USER = CI_TEST_USER;
module.exports.DEFAULT_TEST_USER = DEFAULT_TEST_USER;