/* Auth Module JavaScript - Login, Register, Forgot Password, Reset Password */

/**
 * Toggle password visibility
 * @param {string} inputId - ID of the password input
 * @param {string} eyeIconId - ID of the eye icon
 * @param {string} eyeOffIconId - ID of the eye-off icon
 */
function togglePassword(inputId = 'password', eyeIconId = 'eye-icon', eyeOffIconId = 'eye-off-icon') {
    const passwordInput = document.getElementById(inputId);
    const eyeIcon = document.getElementById(eyeIconId);
    const eyeOffIcon = document.getElementById(eyeOffIconId);

    if (passwordInput.type === 'password') {
        passwordInput.type = 'text';
        if (eyeIcon) eyeIcon.style.display = 'none';
        if (eyeOffIcon) eyeOffIcon.style.display = 'block';
    } else {
        passwordInput.type = 'password';
        if (eyeIcon) eyeIcon.style.display = 'block';
        if (eyeOffIcon) eyeOffIcon.style.display = 'none';
    }
}

/**
 * Initiate OAuth login flow
 * @param {string} provider - OAuth provider name (google, microsoft, github, apple)
 */
function oauthLogin(provider) {
    window.location.href = `/api/auth/oauth/${provider}`;
}

/**
 * Show 2FA challenge section
 * @param {string} sessionToken - Session token for 2FA verification
 */
function showTwoFAChallenge(sessionToken) {
    document.getElementById('login-section').style.display = 'none';
    document.getElementById('twofa-section').classList.add('visible');
    document.getElementById('session-token').value = sessionToken;

    // Focus first code input
    const firstInput = document.querySelector('.code-input[data-index="0"]');
    if (firstInput) firstInput.focus();
}

/**
 * Return to login section from 2FA
 */
function backToLogin() {
    document.getElementById('login-section').style.display = 'block';
    document.getElementById('twofa-section').classList.remove('visible');

    // Clear code inputs
    document.querySelectorAll('.code-input').forEach(input => {
        input.value = '';
        input.classList.remove('filled');
    });
}

/**
 * Update the hidden full code field from individual inputs
 */
function updateFullCode() {
    const codeInputs = document.querySelectorAll('.code-input');
    const code = Array.from(codeInputs).map(input => input.value).join('');
    const fullCodeInput = document.getElementById('full-code');
    if (fullCodeInput) fullCodeInput.value = code;
}

/**
 * Initialize 2FA code input handling
 */
function initCodeInputs() {
    const codeInputs = document.querySelectorAll('.code-input');

    codeInputs.forEach((input, index) => {
        input.addEventListener('input', (e) => {
            const value = e.target.value;

            // Only allow numbers
            e.target.value = value.replace(/[^0-9]/g, '');

            if (e.target.value) {
                e.target.classList.add('filled');
                // Move to next input
                if (index < codeInputs.length - 1) {
                    codeInputs[index + 1].focus();
                }
            } else {
                e.target.classList.remove('filled');
            }

            updateFullCode();
        });

        input.addEventListener('keydown', (e) => {
            // Handle backspace
            if (e.key === 'Backspace' && !e.target.value && index > 0) {
                codeInputs[index - 1].focus();
            }

            // Handle paste
            if (e.key === 'v' && (e.ctrlKey || e.metaKey)) {
                e.preventDefault();
                navigator.clipboard.readText().then(text => {
                    const code = text.replace(/[^0-9]/g, '').slice(0, 6);
                    code.split('').forEach((char, i) => {
                        if (codeInputs[i]) {
                            codeInputs[i].value = char;
                            codeInputs[i].classList.add('filled');
                        }
                    });
                    updateFullCode();
                    if (code.length === 6) {
                        codeInputs[5].focus();
                    }
                });
            }
        });

        // Handle paste directly on input
        input.addEventListener('paste', (e) => {
            e.preventDefault();
            const text = e.clipboardData.getData('text');
            const code = text.replace(/[^0-9]/g, '').slice(0, 6);
            code.split('').forEach((char, i) => {
                if (codeInputs[i]) {
                    codeInputs[i].value = char;
                    codeInputs[i].classList.add('filled');
                }
            });
            updateFullCode();
            if (code.length === 6) {
                codeInputs[5].focus();
            }
        });
    });
}

/**
 * Resend 2FA code with cooldown
 */
let resendCooldown = 0;
function resendCode() {
    if (resendCooldown > 0) return;

    const sessionToken = document.getElementById('session-token').value;
    fetch('/api/auth/2fa/resend', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ session_token: sessionToken })
    });

    // Start cooldown
    resendCooldown = 60;
    const resendBtn = document.getElementById('resend-btn');
    resendBtn.disabled = true;

    const interval = setInterval(() => {
        resendCooldown--;
        resendBtn.textContent = `Resend code (${resendCooldown}s)`;

        if (resendCooldown <= 0) {
            clearInterval(interval);
            resendBtn.textContent = 'Resend code';
            resendBtn.disabled = false;
        }
    }, 1000);
}

/**
 * Show error message
 * @param {string} message - Error message to display
 */
function showError(message) {
    const errorBox = document.getElementById('error-message');
    const errorText = document.getElementById('error-text');
    if (errorText) errorText.textContent = message;
    if (errorBox) errorBox.classList.add('visible');
}

/**
 * Hide error message
 */
function hideError() {
    const errorBox = document.getElementById('error-message');
    if (errorBox) errorBox.classList.remove('visible');
}

/**
 * Show success message
 * @param {string} message - Success message to display
 */
function showSuccess(message) {
    const successBox = document.getElementById('success-message');
    const successText = document.getElementById('success-text');
    if (successText) successText.textContent = message;
    if (successBox) successBox.classList.add('visible');
}

/**
 * Set loading state on a button
 * @param {string} btnId - Button ID
 * @param {boolean} loading - Loading state
 */
function setLoading(btnId, loading) {
    const btn = document.getElementById(btnId);
    if (!btn) return;
    
    if (loading) {
        btn.classList.add('loading');
        btn.disabled = true;
    } else {
        btn.classList.remove('loading');
        btn.disabled = false;
    }
}

/**
 * Check password strength
 * @param {string} password - Password to check
 * @returns {object} - Strength level and requirements met
 */
function checkPasswordStrength(password) {
    const requirements = {
        length: password.length >= 8,
        lowercase: /[a-z]/.test(password),
        uppercase: /[A-Z]/.test(password),
        number: /[0-9]/.test(password),
        special: /[!@#$%^&*(),.?":{}|<>]/.test(password)
    };

    const metCount = Object.values(requirements).filter(Boolean).length;
    
    let strength = 'weak';
    if (metCount >= 5) strength = 'strong';
    else if (metCount >= 4) strength = 'good';
    else if (metCount >= 3) strength = 'fair';

    return { strength, requirements, metCount };
}

/**
 * Update password strength indicator
 * @param {string} password - Password to check
 */
function updatePasswordStrength(password) {
    const { strength, requirements } = checkPasswordStrength(password);
    
    const strengthFill = document.querySelector('.strength-fill');
    const strengthText = document.querySelector('.strength-text');
    
    if (strengthFill) {
        strengthFill.className = 'strength-fill ' + strength;
    }
    
    if (strengthText) {
        const labels = { weak: 'Weak', fair: 'Fair', good: 'Good', strong: 'Strong' };
        strengthText.textContent = labels[strength];
    }

    // Update requirement indicators
    Object.entries(requirements).forEach(([key, met]) => {
        const reqEl = document.querySelector(`.requirement[data-req="${key}"]`);
        if (reqEl) {
            reqEl.classList.toggle('met', met);
        }
    });
}

/**
 * Initialize password strength checker
 */
function initPasswordStrength() {
    const passwordInput = document.getElementById('password');
    if (passwordInput) {
        passwordInput.addEventListener('input', (e) => {
            updatePasswordStrength(e.target.value);
        });
    }
}

/**
 * Handle HTMX events for auth forms
 */
function initHtmxHandlers() {
    document.body.addEventListener('htmx:beforeRequest', function(event) {
        hideError();
        if (event.target.id === 'login-form') {
            setLoading('login-btn', true);
        } else if (event.target.id === 'twofa-form') {
            setLoading('verify-btn', true);
        } else if (event.target.id === 'register-form') {
            setLoading('register-btn', true);
        } else if (event.target.id === 'forgot-form') {
            setLoading('forgot-btn', true);
        } else if (event.target.id === 'reset-form') {
            setLoading('reset-btn', true);
        }
    });

    document.body.addEventListener('htmx:afterRequest', function(event) {
        if (event.target.id === 'login-form') {
            setLoading('login-btn', false);
        } else if (event.target.id === 'twofa-form') {
            setLoading('verify-btn', false);
        } else if (event.target.id === 'register-form') {
            setLoading('register-btn', false);
        } else if (event.target.id === 'forgot-form') {
            setLoading('forgot-btn', false);
        } else if (event.target.id === 'reset-form') {
            setLoading('reset-btn', false);
        }

        if (event.detail.successful) {
            try {
                const response = JSON.parse(event.detail.xhr.responseText);

                // Check if 2FA is required
                if (response.requires_2fa) {
                    showTwoFAChallenge(response.session_token);
                    return;
                }

                // Successful login/register - redirect
                if (response.redirect || response.success) {
                    window.location.href = response.redirect || '/';
                }

                // Show success message
                if (response.message) {
                    showSuccess(response.message);
                }
            } catch (e) {
                // If response is not JSON, check for redirect header
                if (event.detail.xhr.status === 200) {
                    window.location.href = '/';
                }
            }
        } else {
            // Show error
            try {
                const response = JSON.parse(event.detail.xhr.responseText);
                showError(response.error || 'An error occurred. Please try again.');
            } catch (e) {
                showError('An error occurred. Please try again.');
            }
        }
    });
}

/**
 * Initialize auth module
 */
function initAuth() {
    initCodeInputs();
    initPasswordStrength();
    initHtmxHandlers();

    // Clear error when user starts typing
    document.querySelectorAll('.form-input').forEach(input => {
        input.addEventListener('input', hideError);
    });
}

// Auto-initialize when DOM is ready
if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', initAuth);
} else {
    initAuth();
}