(() => {
    const API_BASE_URL = `https://${window.location.hostname}`;
    
    // API helper function
    async function api(endpoint, options = {}) {
        try {
            const url = endpoint.startsWith('http') ? endpoint : API_BASE_URL + endpoint;
            const response = await fetch(url, {
                ...options,
                credentials: 'include', // Include cookies
                headers: {
                    'Content-Type': 'application/json',
                    ...options.headers
                }
            });
            
            const data = await response.json();
            
            if (!response.ok) {
                throw new Error(data.message || 'API request failed');
            }
            
            return data;
        } catch (err) {
            console.error('API Error:', err);
            throw err;
        }
    }

    // Elements
    const loginForm = document.getElementById('loginForm');
    const signInBtn = document.getElementById('signInBtn');
    const anonBtn = document.getElementById('anonBtn');
    const emailInput = document.getElementById('loginEmail');
    const emailHint = document.getElementById('emailHint');
    const passwordInput = document.getElementById('loginPassword');
    const togglePasswordBtn = document.getElementById('togglePassword');
    const meter = document.getElementById('passwordMeter');
    const meterBar = document.getElementById('passwordMeterBar');
    const capsLockIndicator = document.getElementById('capsLockIndicator');
    const rememberMe = document.getElementById('rememberMe');
    const forgotLink = document.getElementById('forgotLink');
    // Forgot password elements
    const fpModal = document.getElementById('fpModal');
    const fpBackdrop = document.getElementById('fpBackdrop');
    const fpClose = document.getElementById('fpClose');
    const fpEmail = document.getElementById('fpEmail');
    const fpRequestBtn = document.getElementById('fpRequestBtn');
    const fpStep1 = document.querySelector('.fp-step-1');
    const fpStep2 = document.querySelector('.fp-step-2');
    const fpCode = document.getElementById('fpCode');
    const fpNewPassword = document.getElementById('fpNewPassword');
    const fpApplyBtn = document.getElementById('fpApplyBtn');
    const fpResendBtn = document.getElementById('fpResendBtn');
    const fpMessage = document.getElementById('fpMessage');
    // MFA elements
    const mfaModal = document.getElementById('mfaModal');
    const mfaBackdrop = document.getElementById('mfaBackdrop');
    const mfaClose = document.getElementById('mfaClose');
    const mfaCode = document.getElementById('mfaCode');
    const mfaVerifyBtn = document.getElementById('mfaVerifyBtn');
    const mfaResendBtn = document.getElementById('mfaResendBtn');
    const mfaMessage = document.getElementById('mfaMessage');
    
    // Show message
    function showMessage(text, type = 'error') {
        const existing = document.querySelector('.error-message, .success-message');
        if (existing) existing.remove();
        
        const message = document.createElement('div');
        message.className = type === 'error' ? 'error-message' : 'success-message';
        message.textContent = text;
        message.style.cssText = `
            padding: 12px 16px;
            margin: 16px 0;
            border-radius: 6px;
            font-size: 14px;
            font-weight: 500;
            ${type === 'error' ? 
                'background: rgba(239, 68, 68, 0.1); color: #ef4444; border: 1px solid rgba(239, 68, 68, 0.2);' : 
                'background: rgba(16, 185, 129, 0.1); color: #10b981; border: 1px solid rgba(16, 185, 129, 0.2);'
            }
        `;
        
        loginForm.insertBefore(message, loginForm.firstChild);
        
        setTimeout(() => message.remove(), 5000);
    }
    
    // Redirect to main app
    function redirectToApp(account = null) {
        if (account) {
            localStorage.setItem('aimhsa_account', account);
        }
        window.location.href = '/index.html';
    }

    // Utility: simple password strength score (0..4)
    function getPasswordStrengthScore(pw) {
        let score = 0;
        if (!pw) return 0;
        if (pw.length >= 8) score++;
        if (/[A-Z]/.test(pw)) score++;
        if (/[a-z]/.test(pw)) score++;
        if (/[0-9]/.test(pw)) score++;
        if (/[^A-Za-z0-9]/.test(pw)) score++;
        return Math.min(score, 4);
    }

    function updatePasswordMeter() {
        const pw = passwordInput.value;
        const score = getPasswordStrengthScore(pw);
        const pct = (score / 4) * 100;
        meterBar.style.width = pct + '%';
        let color = '#ef4444';
        if (score >= 3) color = '#f59e0b';
        if (score >= 4) color = '#10b981';
        meterBar.style.background = color;
        meter.setAttribute('aria-hidden', pw ? 'false' : 'true');
    }

    // Toggle password visibility
    togglePasswordBtn?.addEventListener('click', () => {
        const isPassword = passwordInput.type === 'password';
        passwordInput.type = isPassword ? 'text' : 'password';
        togglePasswordBtn.setAttribute('aria-pressed', String(isPassword));
    });

    // Caps lock indicator
    function handleKeyEventForCaps(e) {
        if (typeof e.getModifierState === 'function') {
            const on = e.getModifierState('CapsLock');
            if (on) {
                capsLockIndicator?.removeAttribute('hidden');
            } else {
                capsLockIndicator?.setAttribute('hidden', '');
            }
        }
    }
    passwordInput.addEventListener('keydown', handleKeyEventForCaps);
    passwordInput.addEventListener('keyup', handleKeyEventForCaps);
    passwordInput.addEventListener('input', () => {
        updatePasswordMeter();
    });

    // Remember me: prefill email
    const savedEmail = localStorage.getItem('aimhsa_saved_email');
    if (savedEmail) {
        emailInput.value = savedEmail;
        rememberMe.checked = true;
    }

    // Email basic validation hint
    emailInput.addEventListener('input', () => {
        const v = emailInput.value.trim();
        if (!v) {
            emailHint.textContent = '';
            return;
        }
        const emailPattern = /^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$/;
        emailHint.textContent = !emailPattern.test(v) ? 'Please enter a valid email address' : '';
    });

    // Forgot password (client-side placeholder)
    forgotLink.addEventListener('click', (e) => {
        e.preventDefault();
        openFpModal();
    });

    // Simple cooldown after repeated failures
    const COOLDOWN_KEY = 'aimhsa_login_cooldown_until';
    function isInCooldown() {
        const until = Number(localStorage.getItem(COOLDOWN_KEY) || '0');
        return Date.now() < until;
    }
    function applyCooldown(seconds) {
        const until = Date.now() + seconds * 1000;
        localStorage.setItem(COOLDOWN_KEY, String(until));
    }
    function getCooldownRemainingMs() {
        const until = Number(localStorage.getItem(COOLDOWN_KEY) || '0');
        return Math.max(0, until - Date.now());
    }
    function updateCooldownUI() {
        const remaining = getCooldownRemainingMs();
        if (remaining > 0) {
            signInBtn.disabled = true;
            const secs = Math.ceil(remaining / 1000);
            signInBtn.textContent = `Try again in ${secs}s`;
        } else {
            signInBtn.disabled = false;
            signInBtn.textContent = 'Sign In';
        }
    }
    if (isInCooldown()) {
        updateCooldownUI();
        const timer = setInterval(() => {
            updateCooldownUI();
            if (!isInCooldown()) clearInterval(timer);
        }, 500);
    }
    
    // Login form submission
    loginForm.addEventListener('submit', async (e) => {
        e.preventDefault();
        if (isInCooldown()) {
            updateCooldownUI();
            return;
        }
        
        const email = emailInput.value.trim();
        const password = passwordInput.value;
        
        if (!email || !password) {
            showMessage('Please enter both email and password');
            return;
        }
        
        // Email validation
        const emailPattern = /^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$/;
        if (!emailPattern.test(email)) {
            showMessage('Please enter a valid email address');
            return;
        }
        
        if (rememberMe.checked) {
            localStorage.setItem('aimhsa_saved_email', email);
        } else {
            localStorage.removeItem('aimhsa_saved_email');
        }
        
        signInBtn.disabled = true;
        signInBtn.textContent = 'Signing in...';
        
        try {
            // Try user login first
            try {
                console.log('Trying user login for:', email);
                const res = await api('/api/login', {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({ email, password })
                });
                
                if (res && res.mfa_required) {
                    // Launch MFA modal
                    openMfaModal({ flow: 'user', email, token: res.mfa_token });
                } else {
                    showMessage('Successfully signed in as user!', 'success');
                    setTimeout(() => redirectToApp(res.account || email), 1000);
                }
                return;
            } catch (userErr) {
                console.log('User login failed:', userErr.message);
                console.log('Trying professional login...');
            }
            
            // Try professional login
            try {
                console.log('Trying professional login for:', email);
                const res = await api('/professional/login', {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({ email, password })
                });
                
                // Store professional data
                localStorage.setItem('aimhsa_professional', JSON.stringify(res));
                if (res && res.mfa_required) {
                    openMfaModal({ flow: 'professional', email, token: res.mfa_token });
                } else {
                    showMessage('Successfully signed in as professional!', 'success');
                    setTimeout(() => {
                        window.location.href = '/professional_dashboard.html';
                    }, 1000);
                }
                return;
            } catch (profErr) {
                console.log('Professional login failed:', profErr.message);
                console.log('Trying admin login...');
            }
            
            // Try admin login
            try {
                console.log('Trying admin login for:', email);
                const res = await api('/admin/login', {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({ username: email, password })
                });
                
                console.log('Admin login successful:', res);
                // Store admin data
                localStorage.setItem('aimhsa_admin', JSON.stringify(res));
                if (res && res.mfa_required) {
                    openMfaModal({ flow: 'admin', email, token: res.mfa_token });
                } else {
                    showMessage('Successfully signed in as admin!', 'success');
                    setTimeout(() => {
                        window.location.href = res.redirect || '/admin_dashboard.html';
                    }, 1000);
                }
                return;
            } catch (adminErr) {
                console.log('Admin login failed:', adminErr.message);
            }
            
            // If all login attempts failed
            showMessage('Invalid username or password. Please check your credentials.');
            // backoff: 10s cooldown after aggregated failure
            applyCooldown(10);
            updateCooldownUI();
            
        } catch (err) {
            console.error('Login error:', err);
            showMessage('Login failed. Please try again.');
        } finally {
            signInBtn.disabled = false;
            signInBtn.textContent = 'Sign In';
        }
    });
    
    // Anonymous access
    anonBtn.addEventListener('click', () => {
        localStorage.setItem('aimhsa_account', 'null');
        window.location.href = '/index.html';
    });
    
    // Check if already logged in
    const account = localStorage.getItem('aimhsa_account');
    if (account && account !== 'null') {
        redirectToApp(account);
    }

    // --- MFA helpers ---
    function openMfaModal(context) {
        mfaModal.classList.add('open');
        mfaModal.setAttribute('aria-hidden', 'false');
        mfaCode.value = '';
        mfaMessage.textContent = '';
        mfaCode.focus();

        function close() {
            mfaModal.classList.remove('open');
            mfaModal.setAttribute('aria-hidden', 'true');
        }

        function onClose() {
            close();
            cleanup();
        }

        async function verify() {
            const code = mfaCode.value.trim();
            if (!/^[0-9]{6}$/.test(code)) {
                mfaMessage.textContent = 'Please enter a valid 6-digit code.';
                return;
            }
            mfaVerifyBtn.disabled = true;
            mfaVerifyBtn.textContent = 'Verifying...';
            try {
                const endpoint =
                    context.flow === 'admin' ? '/admin/mfa/verify' :
                    context.flow === 'professional' ? '/professional/mfa/verify' :
                    '/mfa/verify';
                const res = await api(endpoint, {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({ username: context.username, code, token: context.token })
                });
                mfaMessage.textContent = 'MFA verified. Redirecting...';
                setTimeout(() => {
                    if (context.flow === 'admin') {
                        window.location.href = '/admin_dashboard.html';
                    } else if (context.flow === 'professional') {
                        window.location.href = '/professional_dashboard.html';
                    } else {
                        redirectToApp(context.username);
                    }
                }, 600);
            } catch (err) {
                mfaMessage.textContent = 'Invalid or expired code. Please try again.';
            } finally {
                mfaVerifyBtn.disabled = false;
                mfaVerifyBtn.textContent = 'Verify';
            }
        }

        async function resend() {
            try {
                const endpoint =
                    context.flow === 'admin' ? '/admin/mfa/resend' :
                    context.flow === 'professional' ? '/professional/mfa/resend' :
                    '/mfa/resend';
                await api(endpoint, {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({ username: context.username, token: context.token })
                });
                mfaMessage.textContent = 'Code resent.';
            } catch (err) {
                mfaMessage.textContent = 'Could not resend code. Try again later.';
            }
        }

        function cleanup() {
            mfaBackdrop.removeEventListener('click', onClose);
            mfaClose.removeEventListener('click', onClose);
            mfaVerifyBtn.removeEventListener('click', verify);
            mfaResendBtn.removeEventListener('click', resend);
        }

        mfaBackdrop.addEventListener('click', onClose);
        mfaClose.addEventListener('click', onClose);
        mfaVerifyBtn.addEventListener('click', verify);
        mfaResendBtn.addEventListener('click', resend);
    }

    // --- Forgot Password helpers ---
    function openFpModal() {
        fpModal.classList.add('open');
        fpModal.setAttribute('aria-hidden', 'false');
        fpMessage.textContent = '';
        fpStep1.classList.remove('hidden');
        fpStep2.classList.add('hidden');
        fpEmail.value = emailInput.value.trim();
        setTimeout(() => fpEmail.focus(), 0);

        function close() {
            fpModal.classList.remove('open');
            fpModal.setAttribute('aria-hidden', 'true');
        }

        function onClose() {
            close();
            cleanup();
        }

        async function requestCode() {
            console.log('Request code function called');
            console.log('fpEmail element:', fpEmail);
            console.log('fpEmail value:', fpEmail ? fpEmail.value : 'fpEmail is null');
            const email = fpEmail.value.trim();
            console.log('Email:', email);
            
            if (!email) {
                fpMessage.textContent = 'Please enter your email address.';
                fpMessage.style.display = 'block';
                return;
            }
            
            // Email validation
            const emailPattern = /^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$/;
            if (!emailPattern.test(email)) {
                fpMessage.textContent = 'Please enter a valid email address.';
                fpMessage.style.display = 'block';
                return;
            }
            
            fpRequestBtn.disabled = true;
            fpRequestBtn.textContent = 'Sending...';
            fpMessage.style.display = 'none';
            
            try {
                console.log('Making API call to /forgot_password');
                const res = await api('/forgot_password', {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({ email: email })
                });
                
                console.log('API response:', res);
                
                if (res && res.ok) {
                    // Show success message and token
                    let message = res.message || 'Reset code sent successfully!';
                    if (res.token) {
                        message += ` Your reset code is: ${res.token}`;
                    }
                    fpMessage.textContent = message;
                    fpMessage.style.display = 'block';
                    fpMessage.className = 'modal-message success';
                    
                    // Move to step 2
                    fpStep1.classList.add('hidden');
                    fpStep2.classList.remove('hidden');
                    fpCode.value = '';
                    fpNewPassword.value = '';
                    setTimeout(() => fpCode.focus(), 0);
                } else {
                    fpMessage.textContent = res.error || 'Failed to send reset code.';
                    fpMessage.style.display = 'block';
                    fpMessage.className = 'modal-message error';
                }
            } catch (err) {
                console.error('Forgot password error:', err);
                fpMessage.textContent = 'Could not initiate reset. Please check your connection and try again.';
                fpMessage.style.display = 'block';
                fpMessage.className = 'modal-message error';
            } finally {
                fpRequestBtn.disabled = false;
                fpRequestBtn.textContent = 'Send code';
            }
        }

        async function applyReset() {
            console.log('Apply reset function called');
            const email = fpEmail.value.trim();
            const code = fpCode.value.trim();
            const newPw = fpNewPassword.value;
            
            console.log('Reset data:', { email, code, newPw: '***' });
            
            if (!/^[0-9A-Z]{6}$/.test(code)) {
                fpMessage.textContent = 'Please enter the 6-character code.';
                fpMessage.style.display = 'block';
                fpMessage.className = 'modal-message error';
                return;
            }
            if (newPw.length < 6) {
                fpMessage.textContent = 'New password must be at least 6 characters.';
                fpMessage.style.display = 'block';
                fpMessage.className = 'modal-message error';
                return;
            }
            
            fpApplyBtn.disabled = true;
            fpApplyBtn.textContent = 'Resetting...';
            fpMessage.style.display = 'none';
            
            try {
                console.log('Making API call to /reset_password');
                const res = await api('/reset_password', {
                    method: 'POST',
                    headers: { 'Content-Type': 'application/json' },
                    body: JSON.stringify({ email: email, token: code, new_password: newPw })
                });
                
                console.log('Reset password response:', res);
                
                if (res && res.ok) {
                    fpMessage.textContent = res.message || 'Password updated successfully! You can now sign in.';
                    fpMessage.style.display = 'block';
                    fpMessage.className = 'modal-message success';
                    
                    setTimeout(() => {
                        onClose();
                        emailInput.value = email;
                        passwordInput.focus();
                    }, 2000);
                } else {
                    fpMessage.textContent = res.error || 'Invalid code or error updating password.';
                    fpMessage.style.display = 'block';
                    fpMessage.className = 'modal-message error';
                }
            } catch (err) {
                console.error('Reset password error:', err);
                fpMessage.textContent = 'Invalid code or error updating password. Please try again.';
                fpMessage.style.display = 'block';
                fpMessage.className = 'modal-message error';
            } finally {
                fpApplyBtn.disabled = false;
                fpApplyBtn.textContent = 'Reset password';
            }
        }

        async function resendCode() {
            // Reuse forgot_password to resend
            requestCode();
        }

        function cleanup() {
            fpBackdrop.removeEventListener('click', onClose);
            fpClose.removeEventListener('click', onClose);
            fpRequestBtn.removeEventListener('click', requestCode);
            fpApplyBtn.removeEventListener('click', applyReset);
            fpResendBtn.removeEventListener('click', resendCode);
        }

        fpBackdrop.addEventListener('click', onClose);
        fpClose.addEventListener('click', onClose);
        
        console.log('Attaching event listener to fpRequestBtn:', fpRequestBtn);
        fpRequestBtn.addEventListener('click', requestCode);
        
        fpApplyBtn.addEventListener('click', applyReset);
        fpResendBtn.addEventListener('click', resendCode);
    }
})();