/**
 * User Manager Module
 * Handles user registration, preferences, and status management
 */

class UserManager {
    constructor(apiClient, uiComponents) {
        this.apiClient = apiClient;
        this.ui = uiComponents;
        this.currentUser = null;
    }

    /**
     * Check if user exists and load their preferences
     * @param {string} email - User email
     * @param {boolean} showLoading - Whether to show loading indicator
     */
    async loadUserByEmail(email, showLoading = false) {
        try {
            if (showLoading) {
                this.ui.showLoading('Loading user data...');
            }
            
            const user = await this.apiClient.getUserByEmail(email);
            if (user) {
                this.currentUser = user;
                return user;
            }
            return null;
        } catch (error) {
            console.log('User not found or error loading user:', error.message);
            return null;
        } finally {
            if (showLoading) {
                this.ui.hideLoading();
            }
        }
    }

    /**
     * Register a new user or update existing user
     * @param {string} email - User email
     * @param {string} preferences - User preferences
     */
    async registerOrUpdateUser(email, preferences) {
        try {
            // Check if user exists first
            const existingUser = await this.loadUserByEmail(email);
            
            let result;
            let message;
            
            if (existingUser) {
                // Update existing user
                result = await this.apiClient.updateUserPreferences(email, preferences);
                message = 'Preferences updated successfully!';
            } else {
                // Register new user
                result = await this.apiClient.registerUser(email, preferences);
                message = 'User registered successfully!';
            }
            
            if (result.success) {
                this.currentUser = result.user;
                this.ui.showSuccessMessage(message);
                return result;
            } else {
                throw new Error(result.message || 'Failed to register/update user');
            }
            
        } catch (error) {
            this.ui.showError(`Failed to register/update user: ${error.message}`);
            throw error;
        }
    }

    /**
     * Toggle user active status
     * @param {string} email - User email
     * @param {boolean} active - Active status
     */
    async toggleUserActive(email, active) {
        try {
            const result = await this.apiClient.toggleUserActive(email, active);
            
            if (result.success) {
                const action = active ? 'activated' : 'deactivated';
                this.ui.showSuccessMessage(`Notifications ${action} successfully!`);
                
                // Update current user if it matches
                if (this.currentUser && this.currentUser.email === email) {
                    this.currentUser.active = active;
                }
                
                return result;
            } else {
                throw new Error(result.message || 'Failed to toggle user status');
            }
            
        } catch (error) {
            this.ui.showError(`Failed to toggle user status: ${error.message}`);
            throw error;
        }
    }

    /**
     * Deactivate user notifications
     * @param {string} email - User email
     */
    async deactivateUser(email) {
        const confirmed = confirm(`Are you sure you want to deactivate daily notifications for ${email}?`);
        if (!confirmed) return false;
        
        return await this.toggleUserActive(email, false);
    }

    /**
     * Reactivate user notifications
     * @param {string} email - User email
     */
    async reactivateUser(email) {
        return await this.toggleUserActive(email, true);
    }

    /**
     * Get current user data
     */
    getCurrentUser() {
        return this.currentUser;
    }

    /**
     * Check if current user is active
     */
    isCurrentUserActive() {
        return this.currentUser && this.currentUser.active;
    }

    /**
     * Clear current user data
     */
    clearCurrentUser() {
        this.currentUser = null;
    }

    /**
     * Validate email format
     * @param {string} email - Email to validate
     */
    validateEmail(email) {
        const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
        return emailRegex.test(email);
    }

    /**
     * Auto-fill user preferences if they exist
     * @param {string} email - User email
     * @param {HTMLElement} preferencesInput - Preferences input field
     */
    async autoFillPreferences(email, preferencesInput) {
        if (!email || !this.validateEmail(email)) {
            return;
        }

        const user = await this.loadUserByEmail(email);
        if (user && user.preferences_text && !preferencesInput.value.trim()) {
            preferencesInput.value = user.preferences_text;
            
            // Auto-resize textarea if it has this functionality
            if (preferencesInput.style) {
                preferencesInput.style.height = 'auto';
                preferencesInput.style.height = preferencesInput.scrollHeight + 'px';
            }
        }
        
        return user;
    }

    /**
     * Create user status display for forms
     * @param {Object} user - User object
     * @param {Function} deactivateCallback - Callback for deactivate action
     * @param {Function} reactivateCallback - Callback for reactivate action
     */
    createUserStatusDisplay(user, deactivateCallback, reactivateCallback) {
        const statusContainer = document.createElement('div');
        statusContainer.id = 'userStatusDisplay';
        statusContainer.style.cssText = `
            margin-top: 1rem;
            padding: 1rem;
            background: #f8f9fa;
            border-radius: 8px;
            border-left: 4px solid var(--success-color);
        `;
        
        const isActive = user.active;
        const statusText = isActive ? 'Scheduled' : 'Inactive';
        const statusColor = isActive ? 'var(--success-color)' : 'var(--warning-color)';
        
        statusContainer.innerHTML = `
            <div style="display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 1rem;">
                <div style="display: flex; align-items: center; gap: 0.5rem;">
                    <i class="fas fa-${isActive ? 'check-circle' : 'pause-circle'}" style="color: ${statusColor};"></i>
                    <span style="font-weight: 500;">Daily notifications: <span style="color: ${statusColor};">${statusText}</span></span>
                </div>
                <div style="display: flex; gap: 0.5rem;">
                    ${isActive ? `
                        <button type="button" class="btn btn-success btn-sm" style="pointer-events: none;">
                            <i class="fas fa-check"></i> Scheduled
                        </button>
                        <button type="button" class="btn btn-danger btn-sm" id="deactivateFromForm">
                            <i class="fas fa-times"></i> Deactivate
                        </button>
                    ` : `
                        <button type="button" class="btn btn-primary btn-sm" id="reactivateFromForm">
                            <i class="fas fa-play"></i> Reactivate
                        </button>
                    `}
                </div>
            </div>
        `;
        
        // Add event listeners
        const deactivateBtn = statusContainer.querySelector('#deactivateFromForm');
        const reactivateBtn = statusContainer.querySelector('#reactivateFromForm');
        
        if (deactivateBtn) {
            deactivateBtn.addEventListener('click', deactivateCallback);
        }
        if (reactivateBtn) {
            reactivateBtn.addEventListener('click', reactivateCallback);
        }
        
        return statusContainer;
    }

    /**
     * Remove user status display
     */
    removeUserStatusDisplay() {
        const statusDisplay = document.getElementById('userStatusDisplay');
        if (statusDisplay) {
            statusDisplay.remove();
        }
    }
}