// 导入Live2D控制器
import { Live2DController } from './live2d-controller.js';

class AITeacherApp {
    constructor() {
        // PDF相关变量
        this.pdfDoc = null;
        this.pageNum = 1;
        this.pageRendering = false;
        this.pageNumPending = null;
        this.scale = 1.0;
        this.canvas = document.getElementById('pdf-canvas');
        this.ctx = this.canvas.getContext('2d');
        this.messageTimeout = null;
        
        // Live2D控制器
        this.live2dController = null;
        
        // 初始化PDF.js
        pdfjsLib.GlobalWorkerOptions.workerSrc = 'https://cdnjs.cloudflare.com/ajax/libs/pdf.js/3.4.120/pdf.worker.min.js';
        
        // 初始化应用
        this.global_setting = null;
        this.api_host = null;

        // 音频相关
        this.audioPlayer = null;
        this.currentAudioBase64 = null;
        this.selectedVoice = 'zf_xiaoxiao';
        this.speechSpeed = 1.0;

        this.init();
    }
    
    async init() {
        this.global_setting = await fetch('setting.json').then(response => response.json());
        this.api_host = window.location.host;
        if(this.api_host.includes(':')) {
            this.api_host = this.api_host.split(':')[0];
        }
        this.api_host = `${this.api_host}:${this.global_setting.websocket_port}`;
        try {
            console.log('初始化AI教学助手...');
            
            // 初始化Live2D控制器
            try {
                console.log('初始化Live2D控制器...');
                this.live2dController = new Live2DController('live2d-container');
            } catch (error) {
                console.error('初始化Live2D控制器时出错:', error);
            }
            
            // 初始化音频播放器
            this.audioPlayer = document.getElementById('audio-player');
            
            // 初始化语音和语速控制
            this.initVoiceControls();
            
            await this.loadDefaultPDF();       
            this.setupEventListeners();
            
            console.log('AI教学助手初始化成功');
        } catch (error) {
            console.error('初始化AI教学助手时出错:', error);
            this.showMessage('初始化失败: ' + error.message, true);
        }
    }
    
    async loadDefaultPDF() {
        try {
            const defaultPdfPath = './public/pdf/test.pdf';
            const loadingTask = pdfjsLib.getDocument(defaultPdfPath);
            this.pdfDoc = await loadingTask.promise;
            document.getElementById('page-count').textContent = this.pdfDoc.numPages;
            this.renderPage(this.pageNum);
            
            // 通知服务器加载PDF
            this.notifyServerPdfLoad(defaultPdfPath);
        } catch (error) {
            console.error('加载PDF时出错:', error);
            this.showMessage('PDF加载失败: ' + error.message, true);
        }
    }
    
    async notifyServerPdfLoad(pdfPath) {
        try {
            const response = await fetch(`http://${this.api_host}/api/load_pdf`, {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/json'
                },
                body: JSON.stringify({ path: pdfPath })
            });
            
            if (!response.ok) {
                throw new Error('服务器响应错误');
            }
            
            const data = await response.json();
            console.log('服务器PDF加载响应:', data);
            
            if (data.success) {
                this.showMessage(data.message, false);
            } else {
                this.showMessage(data.message, true);
            }
        } catch (error) {
            console.error('通知服务器加载PDF时出错:', error);
            this.showMessage('通知服务器加载PDF时出错: ' + error.message, true);
        }
    }
    
    renderPage(num) {
        this.pageRendering = true;
        this.pdfDoc.getPage(num).then((page) => {
            const viewport = page.getViewport({ scale: this.scale });
            this.canvas.height = viewport.height;
            this.canvas.width = viewport.width;
            
            const renderContext = {
                canvasContext: this.ctx,
                viewport: viewport
            };
            
            const renderTask = page.render(renderContext);
            
            renderTask.promise.then(() => {
                this.pageRendering = false;
                if (this.pageNumPending !== null) {
                    this.renderPage(this.pageNumPending);
                    this.pageNumPending = null;
                }
                
                // 清空讲解区域和停止音频播放
                document.getElementById('explanation-text').textContent = '点击"生成讲解"按钮获取AI讲解';
                this.stopAudio();
                document.getElementById('play-btn').disabled = true;
            });
        });
        
        document.getElementById('page-num').value = num;
    }
    
    queueRenderPage(num) {
        if (this.pageRendering) {
            this.pageNumPending = num;
        } else {
            this.renderPage(num);
        }
    }
    
    onPrevPage() {
        if (this.pageNum <= 1) {
            return;
        }
        this.pageNum--;
        this.queueRenderPage(this.pageNum);
    }
    
    onNextPage() {
        if (this.pageNum >= this.pdfDoc.numPages) {
            return;
        }
        this.pageNum++;
        this.queueRenderPage(this.pageNum);
    }
    
    onPageNumChange(e) {
        const newPageNum = parseInt(e.target.value);
        if (newPageNum > 0 && newPageNum <= this.pdfDoc.numPages) {
            this.pageNum = newPageNum;
            this.queueRenderPage(this.pageNum);
        }
    }
    
    onZoomIn() {
        this.scale += 0.1;
        this.queueRenderPage(this.pageNum);
    }
    
    onZoomOut() {
        if (this.scale <= 0.2) return;
        this.scale -= 0.1;
        this.queueRenderPage(this.pageNum);
    }
    
    onZoomReset() {
        this.scale = 1.0;
        this.queueRenderPage(this.pageNum);
    }
    
    async onFileUpload(e) {
        const file = e.target.files[0];
        if (file && file.type === 'application/pdf') {
            const fileReader = new FileReader();
            
            fileReader.onload = async (event) => {
                const typedarray = new Uint8Array(event.target.result);
                try {
                    const loadingTask = pdfjsLib.getDocument(typedarray);
                    this.pdfDoc = await loadingTask.promise;
                    this.pageNum = 1;
                    document.getElementById('page-count').textContent = this.pdfDoc.numPages;
                    this.renderPage(this.pageNum);
                    this.showMessage('PDF加载成功', false);
                } catch (error) {
                    console.error('加载PDF时出错:', error);
                    this.showMessage('PDF加载失败: ' + error.message, true);
                }
            };
            
            fileReader.readAsArrayBuffer(file);
        } else {
            this.showMessage('请选择有效的PDF文件', true);
        }
    }
    
    async onExplain() {
        try {
            // 显示加载中的消息
            document.getElementById('explanation-text').textContent = '正在生成AI讲解...';
            document.getElementById('play-btn').disabled = true;
            this.stopAudio();
            
            // 获取当前选择的语音和语速
            const voice = this.selectedVoice;
            const speed = this.speechSpeed;
            
            // 发送到服务器获取AI讲解和音频
            const response = await fetch(`http://${this.api_host}/api/explain_with_audio`, {
                method: 'POST',
                headers: {
                    'Content-Type': 'application/json'
                },
                body: JSON.stringify({ 
                    page: this.pageNum,
                    voice: voice,
                    speed: speed
                })
            });
            
            if (!response.ok) {
                throw new Error('服务器响应错误');
            }
            
            const data = await response.json();
            
            if (data.success) {
                document.getElementById('explanation-text').textContent = data.explanation;
                
                // 如果有音频数据，启用播放按钮并自动播放
                if (data.audio_base64) {
                    this.currentAudioBase64 = data.audio_base64;
                    document.getElementById('play-btn').disabled = false;
                    this.playAudio();
                } else if (data.tts_error) {
                    console.error('TTS生成失败:', data.tts_error);
                    this.showMessage('语音生成失败，但文本讲解已生成', true);
                }
                
                // 如果Live2D控制器已初始化，播放说话动作
                if (this.live2dController && this.live2dController.initialized) {
                    this.live2dController.playMotion('Talk', 0);
                }
            } else {
                document.getElementById('explanation-text').textContent = data.explanation || '生成讲解失败';
                this.showMessage('生成讲解失败', true);
            }
        } catch (error) {
            console.error('获取AI讲解时出错:', error);
            document.getElementById('explanation-text').textContent = '获取AI讲解时出错: ' + error.message;
            this.showMessage('获取AI讲解时出错: ' + error.message, true);
        }
    }
    
    playAudio() {
        if (!this.currentAudioBase64) {
            this.showMessage('没有可播放的音频', true);
            return;
        }
        
        try {
            // 将base64转换为Blob
            const byteCharacters = atob(this.currentAudioBase64);
            const byteNumbers = new Array(byteCharacters.length);
            for (let i = 0; i < byteCharacters.length; i++) {
                byteNumbers[i] = byteCharacters.charCodeAt(i);
            }
            const byteArray = new Uint8Array(byteNumbers);
            const blob = new Blob([byteArray], { type: 'audio/wav' });
            
            // 创建URL并设置到音频播放器
            const audioUrl = URL.createObjectURL(blob);
            this.audioPlayer.src = audioUrl;
            this.audioPlayer.style.display = 'block';
            
            // 播放音频
            this.audioPlayer.play();
            
            // 更新播放按钮状态
            const playBtn = document.getElementById('play-btn');
            playBtn.innerHTML = '<i class="bi bi-pause-fill"></i> 暂停';
            playBtn.classList.remove('btn-success');
            playBtn.classList.add('btn-warning');
            
            // 监听音频播放结束事件
            this.audioPlayer.onended = () => {
                playBtn.innerHTML = '<i class="bi bi-play-fill"></i> 播放';
                playBtn.classList.remove('btn-warning');
                playBtn.classList.add('btn-success');
            };
        } catch (error) {
            console.error('播放音频时出错:', error);
            this.showMessage('播放音频时出错: ' + error.message, true);
        }
    }
    
    stopAudio() {
        if (this.audioPlayer) {
            this.audioPlayer.pause();
            this.audioPlayer.currentTime = 0;
            this.audioPlayer.style.display = 'none';
            
            // 更新播放按钮状态
            const playBtn = document.getElementById('play-btn');
            playBtn.innerHTML = '<i class="bi bi-play-fill"></i> 播放';
            playBtn.classList.remove('btn-warning');
            playBtn.classList.add('btn-success');
        }
    }
    
    toggleAudio() {
        if (this.audioPlayer.paused) {
            this.audioPlayer.play();
            document.getElementById('play-btn').innerHTML = '<i class="bi bi-pause-fill"></i> 暂停';
            document.getElementById('play-btn').classList.remove('btn-success');
            document.getElementById('play-btn').classList.add('btn-warning');
        } else {
            this.audioPlayer.pause();
            document.getElementById('play-btn').innerHTML = '<i class="bi bi-play-fill"></i> 播放';
            document.getElementById('play-btn').classList.remove('btn-warning');
            document.getElementById('play-btn').classList.add('btn-success');
        }
    }
    
    initVoiceControls() {
        // 初始化语音选择器
        const voiceSelect = document.getElementById('voice-select');
        voiceSelect.addEventListener('change', () => {
            this.selectedVoice = voiceSelect.value;
        });
        
        // 初始化语速控制
        const speedRange = document.getElementById('speed-range');
        const speedValue = document.getElementById('speed-value');
        
        speedRange.addEventListener('input', () => {
            this.speechSpeed = parseFloat(speedRange.value);
            speedValue.textContent = this.speechSpeed.toFixed(1);
        });
        
        // 设置初始值
        this.selectedVoice = voiceSelect.value;
        this.speechSpeed = parseFloat(speedRange.value);
        speedValue.textContent = this.speechSpeed.toFixed(1);
    }
    
    async loadVoices() {
        try {
            const response = await fetch(`http://${this.api_host}/api/voices`);
            if (!response.ok) {
                throw new Error('获取语音列表失败');
            }
            
            const data = await response.json();
            if (data.success && data.voices && data.voices.length > 0) {
                const voiceSelect = document.getElementById('voice-select');
                
                // 清空现有选项
                voiceSelect.innerHTML = '';
                
                // 添加新选项
                data.voices.forEach(voice => {
                    const option = document.createElement('option');
                    option.value = voice.id;
                    option.textContent = `${voice.name} (${voice.gender === 'female' ? '女' : '男'})`;
                    voiceSelect.appendChild(option);
                });
                
                // 更新选中的语音
                this.selectedVoice = voiceSelect.value;
            }
        } catch (error) {
            console.error('加载语音列表时出错:', error);
        }
    }
    
    showMessage(message, isError = false) {
        const statusMessage = document.getElementById('status-message');
        statusMessage.textContent = message;
        statusMessage.className = isError ? 'error' : 'success';
        statusMessage.style.display = 'block';
        
        // 清除之前的超时
        if (this.messageTimeout) {
            clearTimeout(this.messageTimeout);
        }
        
        // 3秒后隐藏消息
        this.messageTimeout = setTimeout(() => {
            statusMessage.style.display = 'none';
        }, 3000);
    }
    
    setupEventListeners() {
        document.getElementById('prev-page').addEventListener('click', () => this.onPrevPage());
        document.getElementById('next-page').addEventListener('click', () => this.onNextPage());
        document.getElementById('page-num').addEventListener('change', (e) => this.onPageNumChange(e));
        document.getElementById('zoom-in').addEventListener('click', () => this.onZoomIn());
        document.getElementById('zoom-out').addEventListener('click', () => this.onZoomOut());
        document.getElementById('zoom-reset').addEventListener('click', () => this.onZoomReset());
        document.getElementById('pdf-upload').addEventListener('change', (e) => this.onFileUpload(e));
        document.getElementById('explain-btn').addEventListener('click', () => this.onExplain());
        document.getElementById('play-btn').addEventListener('click', () => this.toggleAudio());
        document.getElementById('model-select').addEventListener('change', () => {
            const modelName = document.getElementById('model-select').value;
            this.live2dController.loadModel(modelName);
        });
        
        // 尝试加载可用的语音列表
        this.loadVoices();
    }
}

// 当页面加载完成后初始化应用
window.addEventListener('DOMContentLoaded', () => {
    window.aiTeacherApp = new AITeacherApp();
});