class UIManager {
    constructor() {
        // 延迟初始化，确保DOM已加载
        if (document.readyState === 'loading') {
            document.addEventListener('DOMContentLoaded', () => this.init());
        } else {
            // 如果DOM已经加载完成，则立即初始化
            this.init();
        }
    }
    
    init() {
        console.log('初始化UI管理器...');
        // UI elements
        this.settingsPanel = document.getElementById('settingsPanel');
        this.settingsToggle = document.getElementById('settingsToggle');
        this.closeSettings = document.getElementById('closeSettings');
        this.themeToggle = document.getElementById('themeToggle');
        this.toastContainer = document.getElementById('toastContainer');
        
        // 验证关键元素是否存在
        if (!this.themeToggle) {
            console.error('主题切换按钮未找到！');
            return;
        }
        
        if (!this.toastContainer) {
            console.error('Toast容器未找到！');
            // 尝试创建Toast容器
            this.toastContainer = this.createToastContainer();
        }
        
        // Check for preferred color scheme
        this.checkPreferredColorScheme();
        
        // Initialize event listeners
        this.setupEventListeners();
        
        console.log('UI管理器初始化完成');
    }
    
    createToastContainer() {
        console.log('创建Toast容器');
        const container = document.createElement('div');
        container.id = 'toastContainer';
        container.className = 'toast-container';
        document.body.appendChild(container);
        return container;
    }
    
    checkPreferredColorScheme() {
        const savedTheme = localStorage.getItem('theme');
        const prefersDark = window.matchMedia('(prefers-color-scheme: dark)');
        
        if (savedTheme) {
            this.setTheme(savedTheme === 'dark');
        } else {
            this.setTheme(prefersDark.matches);
        }
        
        prefersDark.addEventListener('change', (e) => this.setTheme(e.matches));
    }
    
    setTheme(isDark) {
        try {
            document.documentElement.setAttribute('data-theme', isDark ? 'dark' : 'light');
            if (this.themeToggle) {
                this.themeToggle.innerHTML = `<i class="fas fa-${isDark ? 'sun' : 'moon'}"></i>`;
            }
            localStorage.setItem('theme', isDark ? 'dark' : 'light');
            console.log(`主题已切换为: ${isDark ? '深色' : '浅色'}`);
        } catch (error) {
            console.error('设置主题时出错:', error);
        }
    }
    
    /**
     * 显示一个Toast消息
     * @param {string} message 显示的消息内容
     * @param {string} type 消息类型，可以是'success', 'error', 'info', 'warning'
     * @param {number} displayTime 显示的时间(毫秒)，如果为-1则持续显示直到手动关闭
     * @returns {HTMLElement} 返回创建的Toast元素，可用于后续移除
     */
    showToast(message, type = 'success', displayTime) {
        try {
            if (!message) {
                console.warn('尝试显示空消息');
                message = '';
            }
            
            if (!this.toastContainer) {
                console.error('Toast容器不存在，正在创建新容器');
                this.toastContainer = this.createToastContainer();
                if (!this.toastContainer) {
                    console.error('无法创建Toast容器，放弃显示消息');
                    return null;
                }
            }
            
            // 检查是否已经存在相同内容的提示
            try {
                const existingToasts = this.toastContainer.querySelectorAll('.toast');
                for (const existingToast of existingToasts) {
                    try {
                        const spanElement = existingToast.querySelector('span');
                        if (spanElement && spanElement.textContent === message) {
                            // 已经存在相同的提示，不再创建新的
                            return existingToast;
                        }
                    } catch (e) {
                        console.warn('检查现有toast时出错:', e);
                        // 继续检查其他toast元素
                    }
                }
            } catch (e) {
                console.warn('查询现有toast时出错:', e);
                // 继续创建新的toast
            }
            
            const toast = document.createElement('div');
            toast.className = `toast ${type}`;
            
            // 根据类型设置图标
            let icon = 'check-circle';
            if (type === 'error') icon = 'exclamation-circle';
            else if (type === 'warning') icon = 'exclamation-triangle';
            else if (type === 'info') icon = 'info-circle';
            
            toast.innerHTML = `
                <i class="fas fa-${icon}"></i>
                <span>${message}</span>
            `;
            
            // 如果是持续显示的Toast，添加关闭按钮
            if (displayTime === -1) {
                const closeButton = document.createElement('button');
                closeButton.className = 'toast-close';
                closeButton.innerHTML = '<i class="fas fa-times"></i>';
                closeButton.addEventListener('click', (e) => {
                    this.hideToast(toast);
                });
                toast.appendChild(closeButton);
                toast.classList.add('persistent');
            }
            
            this.toastContainer.appendChild(toast);
            
            // 为不同类型的提示设置不同的显示时间
            if (displayTime !== -1) {
                // 如果没有指定时间，则根据消息类型和内容长度设置默认时间
                if (displayTime === undefined) {
                    displayTime = message === '截图成功' ? 1500 : 
                                 type === 'error' ? 5000 : 
                                 message.length > 50 ? 4000 : 3000;
                }
                
                setTimeout(() => {
                    this.hideToast(toast);
                }, displayTime);
            }
            
            return toast;
        } catch (error) {
            console.error('显示Toast消息时出错:', error);
            return null;
        }
    }
    
    /**
     * 隐藏一个Toast消息
     * @param {HTMLElement} toast 要隐藏的Toast元素
     */
    hideToast(toast) {
        if (!toast || !toast.parentNode) return;
        
        toast.style.opacity = '0';
        setTimeout(() => {
            if (toast.parentNode) {
                toast.remove();
            }
        }, 300);
    }
    
    closeAllPanels() {
        if (this.settingsPanel) {
            this.settingsPanel.classList.remove('active');
        }
    }
    
    hideSettingsPanel() {
        if (this.settingsPanel) {
            this.settingsPanel.classList.remove('active');
        }
    }
    
    toggleSettingsPanel() {
        if (this.settingsPanel) {
            this.settingsPanel.classList.toggle('active');
        }
    }
    
    closeSettingsPanel() {
        if (this.settingsPanel) {
            this.settingsPanel.classList.remove('active');
        }
    }
    
    // 检查点击事件，如果点击了设置面板外部，则关闭设置面板
    checkClickOutsideSettings(e) {
        if (this.settingsPanel &&
            !this.settingsPanel.contains(e.target) &&
            !e.target.closest('#settingsToggle')) {
            this.settingsPanel.classList.remove('active');
        }
    }
    
    setupEventListeners() {
        // 确保所有元素都存在
        if (!this.settingsToggle || !this.closeSettings || !this.themeToggle) {
            console.error('无法设置事件监听器：一些UI元素未找到');
            return;
        }
        
        // Settings panel
        this.settingsToggle.addEventListener('click', () => {
            this.closeAllPanels();
            this.settingsPanel.classList.toggle('active');
        });
        
        this.closeSettings.addEventListener('click', () => {
            this.settingsPanel.classList.remove('active');
        });
        
        // Theme toggle
        this.themeToggle.addEventListener('click', () => {
            try {
                const currentTheme = document.documentElement.getAttribute('data-theme');
                console.log('当前主题:', currentTheme);
                this.setTheme(currentTheme !== 'dark');
            } catch (error) {
                console.error('切换主题时出错:', error);
            }
        });
        
        // Close panels when clicking outside
        document.addEventListener('click', (e) => {
            this.checkClickOutsideSettings(e);
        });
    }
}

// 创建全局实例
window.UIManager = UIManager;

// 确保在DOM加载完毕后才创建UIManager实例
if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', () => {
        window.uiManager = new UIManager();
    });
} else {
    window.uiManager = new UIManager();
}

// 导出全局辅助函数
window.showToast = (message, type) => {
    if (window.uiManager) {
        return window.uiManager.showToast(message, type);
    } else {
        console.error('UI管理器未初始化，无法显示Toast');
        return null;
    }
};

window.closeAllPanels = () => {
    if (window.uiManager) {
        window.uiManager.closeAllPanels();
    } else {
        console.error('UI管理器未初始化，无法关闭面板');
    }
};