from fastapi import FastAPI, WebSocket, WebSocketDisconnect
import uvicorn
import asyncio
import os
import subprocess
import struct
import base64
import time
import hashlib
import json
from dotenv import load_dotenv
import dashscope
from dashscope.audio.asr import Recognition, RecognitionCallback, RecognitionResult
from dashscope import ImageSynthesis
from dashscope import Generation

# 加载环境变量
load_dotenv()
dashscope.api_key = os.getenv("DASHSCOPE_API_KEY")

app = FastAPI()

# 字体文件配置
FONT_FILE = "GB2312-16.bin"
FONT_CHUNK_SIZE = 512
HIGH_FREQ_CHARS = "的一是在不了有和人这中大为上个国我以要他时来用们生到作地于出就分对成会可主发年动同工也能下过子说产种面而方后多定行学法所民得经十三之进着等部度家电力里如水化高自二理起小物现实加量都两体制机当使点从业本去把性好应开它合还因由其些然前外天政四日那社义事平形相全表间样与关各重新线内数正心反你明看原又么利比或但质气第向道命此变条只没结解问意建月公无系军很情者最立代想已通并提直题党程展五果料象员革位入常文总次品式活设及管特件长求老头基资边流路级少图山统接知较将组见计别她手角期根论运农指几九区强放决西被干做必战先回则任取据处队南给色光门即保治北造百规热领七海口东导器压志世金增争济阶油思术极交受联什认六共权收证改清己美再采转更单风切打白教速花带安场身车例真务具万每目至达走积示议声报斗完类八离华名确才科张信马节话米整空元况今集温传土许步群广石记需段研界拉林律叫且究观越织装影算低持音众书布复容儿须际商非验连断深难近矿千周委素技备半办青省列习响约支般史感劳便团往酸历市克何除消构府称太准精值号率族维划选标写存候毛亲快效斯院查江型眼王按格养易置派层片始却专状育厂京识适属圆包火住调满县局照参红细引听该铁价严龙飞"

# 高频字对应的Unicode码点列表
HIGH_FREQ_UNICODE = [ord(c) for c in HIGH_FREQ_CHARS]

# 字体缓存
font_cache = {}
font_md5 = {}

def calculate_md5(filepath):
    """计算文件的MD5哈希值"""
    if not os.path.exists(filepath):
        return None
    hash_md5 = hashlib.md5()
    with open(filepath, "rb") as f:
        for chunk in iter(lambda: f.read(4096), b""):
            hash_md5.update(chunk)
    return hash_md5.hexdigest()

def init_font_cache():
    """初始化字体缓存和MD5"""
    global font_cache, font_md5
    script_dir = os.path.dirname(os.path.abspath(__file__))
    font_path = os.path.join(script_dir, FONT_FILE)
    
    if not os.path.exists(font_path):
        font_path = os.path.join(script_dir, "..", FONT_FILE)
    
    if os.path.exists(font_path):
        font_md5 = calculate_md5(font_path)
        print(f"Font MD5: {font_md5}")
        
        # 预加载高频字到缓存
        for unicode_val in HIGH_FREQ_UNICODE:
            try:
                char = chr(unicode_val)
                gb_bytes = char.encode('gb2312')
                if len(gb_bytes) == 2:
                    code = struct.unpack('>H', gb_bytes)[0]
                    area = (code >> 8) - 0xA0
                    index = (code & 0xFF) - 0xA0
                    if area >= 1 and index >= 1:
                        offset = ((area - 1) * 94 + (index - 1)) * 32
                        with open(font_path, "rb") as f:
                            f.seek(offset)
                            font_data = f.read(32)
                            if len(font_data) == 32:
                                font_cache[unicode_val] = font_data
            except:
                pass
        print(f"Preloaded {len(font_cache)} high-frequency characters")

# 启动时初始化字体缓存
init_font_cache()

# 存储接收到的音频数据
audio_buffer = bytearray()
RECORDING_RAW_FILE = "received_audio.raw"
RECORDING_MP3_FILE = "received_audio.mp3"
VOLUME_GAIN = 10.0
GENERATED_IMAGE_FILE = "generated_image.png"
GENERATED_THUMB_FILE = "generated_thumb.bin"
OUTPUT_DIR = "output_images"

if not os.path.exists(OUTPUT_DIR):
    os.makedirs(OUTPUT_DIR)

image_counter = 0

def get_output_path():
    global image_counter
    image_counter += 1
    timestamp = time.strftime("%Y%m%d_%H%M%S")
    return os.path.join(OUTPUT_DIR, f"image_{timestamp}_{image_counter}.png")

THUMB_SIZE = 245

# 字体请求队列（用于重试机制）
font_request_queue = {}
FONT_RETRY_MAX = 3


def get_font_data(unicode_val):
    """从字体文件获取单个字符数据（带缓存）"""
    if unicode_val in font_cache:
        return font_cache[unicode_val]
    
    try:
        char = chr(unicode_val)
        gb_bytes = char.encode('gb2312')
        if len(gb_bytes) == 2:
            code = struct.unpack('>H', gb_bytes)[0]
            area = (code >> 8) - 0xA0
            index = (code & 0xFF) - 0xA0
            
            if area >= 1 and index >= 1:
                offset = ((area - 1) * 94 + (index - 1)) * 32
                
                script_dir = os.path.dirname(os.path.abspath(__file__))
                font_path = os.path.join(script_dir, FONT_FILE)
                if not os.path.exists(font_path):
                    font_path = os.path.join(script_dir, "..", FONT_FILE)
                if not os.path.exists(font_path):
                    font_path = FONT_FILE
                
                if os.path.exists(font_path):
                    with open(font_path, "rb") as f:
                        f.seek(offset)
                        font_data = f.read(32)
                        if len(font_data) == 32:
                            font_cache[unicode_val] = font_data
                            return font_data
    except:
        pass
    return None


def send_font_batch_with_retry(websocket, code_list, retry_count=0):
    """批量发送字体数据（带重试机制）"""
    global font_request_queue
    
    success_codes = set()
    failed_codes = []
    
    for code_str in code_list:
        if not code_str:
            continue
        
        try:
            unicode_val = int(code_str)
            font_data = get_font_data(unicode_val)
            
            if font_data:
                import binascii
                hex_data = binascii.hexlify(font_data).decode('utf-8')
                response = f"FONT_DATA:{code_str}:{hex_data}"
                asyncio.run_coroutine_threadsafe(
                    websocket.send_text(response),
                    asyncio.get_event_loop()
                )
                success_codes.add(unicode_val)
            else:
                failed_codes.append(code_str)
        except Exception as e:
            print(f"Error processing font {code_str}: {e}")
            failed_codes.append(code_str)
    
    # 记录失败的请求用于重试
    if failed_codes and retry_count < FONT_RETRY_MAX:
        req_key = f"retry_{retry_count}_{time.time()}"
        font_request_queue[req_key] = {
            'codes': failed_codes,
            'retry': retry_count + 1,
            'timestamp': time.time()
        }
    
    return len(success_codes), failed_codes


async def send_font_with_fragment(websocket, unicode_val):
    """使用二进制分片方式发送字体数据"""
    font_data = get_font_data(unicode_val)
    if not font_data:
        return False
    
    # 分片发送
    total_size = len(font_data)
    chunk_size = FONT_CHUNK_SIZE
    
    for i in range(0, total_size, chunk_size):
        chunk = font_data[i:i+chunk_size]
        seq_num = i // chunk_size
        
        # 构造二进制消息头: 2字节序列号 + 2字节总片数 + 数据
        header = struct.pack('<HH', seq_num, (total_size + chunk_size - 1) // chunk_size)
        payload = header + chunk
        
        await websocket.send_bytes(payload)
    
    return True


async def handle_font_request(websocket, message_type, data):
    """处理字体请求"""
    if message_type == "GET_FONT_MD5":
        # 发送字体文件MD5
        await websocket.send_text(f"FONT_MD5:{font_md5}")
        return
    
    elif message_type == "GET_HIGH_FREQ":
        # 批量获取高频字
        high_freq_list = HIGH_FREQ_UNICODE[:100]  # 限制每次100个
        req_str = ",".join([str(c) for c in high_freq_list])
        await websocket.send_text(f"GET_FONTS_BATCH:{req_str}")
        return
    
    elif message_type.startswith("GET_FONTS_BATCH:"):
        # 批量请求字体
        try:
            codes_str = data
            code_list = codes_str.split(",")
            print(f"Batch Font Request for {len(code_list)} chars")
            
            success_count, failed = send_font_batch_with_retry(websocket, code_list)
            print(f"Font batch: {success_count} success, {len(failed)} failed")
            
            # 发送完成标记
            await websocket.send_text(f"FONT_BATCH_END:{success_count}:{len(failed)}")
            
            # 如果有失败的，进行重试
            if failed:
                await asyncio.sleep(0.5)
                send_font_batch_with_retry(websocket, failed, retry_count=1)
                
        except Exception as e:
            print(f"Error handling batch font request: {e}")
            await websocket.send_text("FONT_BATCH_END:0:0")
        return
    
    elif message_type.startswith("GET_FONT_FRAGMENT:"):
        # 二进制分片传输请求
        try:
            unicode_val = int(data)
            await send_font_with_fragment(websocket, unicode_val)
        except Exception as e:
            print(f"Error sending font fragment: {e}")
        return
    
    elif message_type.startswith("GET_FONT_UNICODE:") or message_type.startswith("GET_FONT:"):
        # 单个字体请求（兼容旧版）
        try:
            is_unicode = message_type.startswith("GET_FONT_UNICODE:")
            code_str = data
            
            if is_unicode:
                unicode_val = int(code_str)
                font_data = get_font_data(unicode_val)
            else:
                code = int(code_str, 16)
                area = (code >> 8) - 0xA0
                index = (code & 0xFF) - 0xA0
                if area >= 1 and index >= 1:
                    offset = ((area - 1) * 94 + (index - 1)) * 32
                    script_dir = os.path.dirname(os.path.abspath(__file__))
                    font_path = os.path.join(script_dir, FONT_FILE)
                    if not os.path.exists(font_path):
                        font_path = os.path.join(script_dir, "..", FONT_FILE)
                    if os.path.exists(font_path):
                        with open(font_path, "rb") as f:
                            f.seek(offset)
                            font_data = f.read(32)
                    else:
                        font_data = None
                else:
                    font_data = None
            
            if font_data:
                import binascii
                hex_data = binascii.hexlify(font_data).decode('utf-8')
                response = f"FONT_DATA:{code_str}:{hex_data}"
                await websocket.send_text(response)
        except Exception as e:
            print(f"Error handling font request: {e}")

class MyRecognitionCallback(RecognitionCallback):
    def __init__(self, websocket: WebSocket, loop: asyncio.AbstractEventLoop):
        self.websocket = websocket
        self.loop = loop
        self.final_text = ""  # 保存最终识别结果

    def on_open(self) -> None:
        print("ASR Session started")

    def on_close(self) -> None:
        print("ASR Session closed")

    def on_event(self, result: RecognitionResult) -> None:
        if result.get_sentence():
             text = result.get_sentence()['text']
             print(f"ASR Result: {text}")
             self.final_text = text  # 保存识别结果
             # 将识别结果发送回客户端
             try:
                 asyncio.run_coroutine_threadsafe(
                     self.websocket.send_text(f"ASR:{text}"), 
                     self.loop
                 )
             except Exception as e:
                 print(f"Failed to send ASR result to client: {e}")

def process_chunk_32_to_16(chunk_bytes, gain=1.0):
    processed_chunk = bytearray()
    # Iterate 4 bytes at a time
    for i in range(0, len(chunk_bytes), 4):
        if i+3 < len(chunk_bytes):
             # 取 chunk[i+2] 和 chunk[i+3] 组成 16-bit signed int
             sample = struct.unpack_from('<h', chunk_bytes, i+2)[0]
             
             # 放大音量
             sample = int(sample * gain)
             
             # 限幅 (Clamping) 防止溢出爆音
             if sample > 32767: sample = 32767
             elif sample < -32768: sample = -32768
             
             # 重新打包为 16-bit little-endian
             processed_chunk.extend(struct.pack('<h', sample))
    return processed_chunk


def optimize_prompt(asr_text):
    """使用大模型优化提示词"""
    print(f"Optimizing prompt for: {asr_text}")
    
    system_prompt = """你是一个AI图像提示词优化专家。将用户简短的语音识别结果转化为详细的、适合AI图像生成的英文提示词。
要求：
1. 保留核心内容和主要元素
2. 添加适合AI绘画的描述词（风格、光线、氛围等）
3. 用英文输出
4. 简洁但描述详细
5. 不要添加多余解释，直接输出优化后的提示词"""

    try:
        response = Generation.call(
            model='qwen-turbo',
            prompt=f'{system_prompt}\n\n用户语音识别结果：{asr_text}\n\n优化后的提示词：',
            max_tokens=200,
            temperature=0.8
        )
        
        if response.status_code == 200:
            optimized = response.output.choices[0].message.content.strip()
            print(f"Optimized prompt: {optimized}")
            return optimized
        else:
            print(f"Prompt optimization failed: {response.code} - {response.message}")
            return asr_text
            
    except Exception as e:
        print(f"Error optimizing prompt: {e}")
        return asr_text


def generate_image(prompt, websocket=None):
    """调用万相文生图API生成图片"""
    print(f"Generating image for prompt: {prompt}")
    
    try:
        response = ImageSynthesis.call(
            model='wan2.6-t2i',
            prompt=prompt,
            size='512x512',
            n=1
        )
        
        if response.status_code == 200:
            image_url = response.output['results'][0]['url']
            print(f"Image generated, downloading from: {image_url}")
            
            import urllib.request
            urllib.request.urlretrieve(image_url, GENERATED_IMAGE_FILE)
            print(f"Image saved to {GENERATED_IMAGE_FILE}")
            
            # 保存一份到 output_images 目录
            output_path = get_output_path()
            import shutil
            shutil.copy(GENERATED_IMAGE_FILE, output_path)
            print(f"Image also saved to {output_path}")
            
            # 缩放图片并转换为RGB565格式
            try:
                from PIL import Image
                img = Image.open(GENERATED_IMAGE_FILE)
                
                # 缩小到THUMB_SIZE x THUMB_SIZE
                img = img.resize((THUMB_SIZE, THUMB_SIZE), Image.LANCZOS)
                
                # 转换为RGB565格式的原始数据
                # 每个像素2字节 (R5 G6 B5)
                rgb565_data = bytearray()
                
                for y in range(THUMB_SIZE):
                    for x in range(THUMB_SIZE):
                        r, g, b = img.getpixel((x, y))[:3]
                        
                        # 转换为RGB565
                        r5 = (r >> 3) & 0x1F
                        g6 = (g >> 2) & 0x3F
                        b5 = (b >> 3) & 0x1F
                        
                        # 小端模式：低字节在前
                        rgb565 = (r5 << 11) | (g6 << 5) | b5
                        rgb565_data.extend(struct.pack('<H', rgb565))
                
                # 保存为.bin文件
                with open(GENERATED_THUMB_FILE, 'wb') as f:
                    f.write(rgb565_data)
                
                print(f"Thumbnail saved to {GENERATED_THUMB_FILE}, size: {len(rgb565_data)} bytes")
                return GENERATED_THUMB_FILE
                
            except ImportError:
                print("PIL not available, sending original image")
                return GENERATED_IMAGE_FILE
            except Exception as e:
                print(f"Error processing image: {e}")
                return GENERATED_IMAGE_FILE
        else:
            print(f"Image generation failed: {response.code} - {response.message}")
            return None
            
    except Exception as e:
        print(f"Error generating image: {e}")
        return None

@app.websocket("/ws/audio")
async def websocket_endpoint(websocket: WebSocket):
    global audio_buffer
    await websocket.accept()
    print("Client connected")
    
    recognition = None
    callback = None  # 保存callback对象
    processed_buffer = bytearray()
    loop = asyncio.get_running_loop()
    
    try:
        while True:
            # 接收消息 (可能是文本指令或二进制音频数据)
            try:
                message = await websocket.receive()
            except RuntimeError as e:
                if "Cannot call \"receive\" once a disconnect message has been received" in str(e):
                    print("Client disconnected (RuntimeError caught)")
                    break
                raise e
            
            if "text" in message:
                text = message["text"]
                print(f"Received text: {text}")
                
                if text == "START_RECORDING":
                    print("Start recording...")
                    audio_buffer = bytearray() # 清空缓冲区
                    processed_buffer = bytearray()
                    
                    # 启动实时语音识别
                    try:
                        callback = MyRecognitionCallback(websocket, loop)
                        recognition = Recognition(
                            model='paraformer-realtime-v2',
                            format='pcm',
                            sample_rate=16000,
                            callback=callback
                        )
                        recognition.start()
                        print("DashScope ASR started")
                    except Exception as e:
                        print(f"Failed to start ASR: {e}")
                        recognition = None
                        callback = None
                    
                elif text == "STOP_RECORDING":
                    print(f"Stop recording. Total raw bytes: {len(audio_buffer)}")
                    
                    # 停止语音识别
                    if recognition:
                        try:
                            recognition.stop()
                            print("DashScope ASR stopped")
                        except Exception as e:
                            print(f"Error stopping ASR: {e}")
                        recognition = None
                    
                    # 使用实时处理过的音频数据
                    processed_audio = processed_buffer
                    
                    print(f"Processed audio size: {len(processed_audio)} bytes (Gain: {VOLUME_GAIN}x)")
                    
                    # 获取ASR识别结果
                    asr_text = ""
                    if callback:
                        asr_text = callback.final_text
                        print(f"Final ASR text: {asr_text}")
                    
                    # 2. 保存原始 RAW 文件 (16-bit PCM)
                    with open(RECORDING_RAW_FILE, "wb") as f:
                        f.write(processed_audio)
                        
                    # 3. 转换为 MP3 并保存 (使用 ffmpeg 命令行，避免 Python 3.13 audioop 问题)
                    try:
                        # ffmpeg -y -f s16le -ar 16000 -ac 1 -i received_audio.raw received_audio.mp3
                        cmd = [
                            "ffmpeg",
                            "-y", # 覆盖输出文件
                            "-f", "s16le", # 输入格式: signed 16-bit little endian
                            "-ar", "16000", # 输入采样率
                            "-ac", "1", # 输入声道数
                            "-i", RECORDING_RAW_FILE,
                            RECORDING_MP3_FILE
                        ]
                        print(f"Running command: {' '.join(cmd)}")
                        
                        # Use asyncio.create_subprocess_exec instead of subprocess.run to avoid blocking the event loop
                        process = await asyncio.create_subprocess_exec(
                            *cmd,
                            stdout=asyncio.subprocess.PIPE,
                            stderr=asyncio.subprocess.PIPE
                        )
                        stdout, stderr = await process.communicate()
                        
                        if process.returncode != 0:
                            raise subprocess.CalledProcessError(process.returncode, cmd, output=stdout, stderr=stderr)
                            
                        print(f"Saved MP3 to {RECORDING_MP3_FILE}")
                    except subprocess.CalledProcessError as e:
                        print(f"Error converting to MP3: {e}")
                        # stderr might be bytes
                        error_msg = e.stderr.decode() if isinstance(e.stderr, bytes) else str(e.stderr)
                        print(f"FFmpeg stderr: {error_msg}")
                    except FileNotFoundError:
                        print("Error: ffmpeg not found. Please install ffmpeg.")
                    except Exception as e:
                         print(f"Error converting to MP3: {e}")

                    # 4. 如果有识别结果，调用文生图API生成图片
                    if asr_text:
                        print(f"Generating image for: {asr_text}")
                        
                        # 先发送 ASR 文字到 ESP32 显示
                        await websocket.send_text(f"ASR:{asr_text}")
                        await websocket.send_text("GENERATING_IMAGE:正在优化提示词...")
                        
                        # 等待一会让 ESP32 显示文字
                        await asyncio.sleep(0.5)
                        
                        # 优化提示词
                        optimized_prompt = await asyncio.to_thread(optimize_prompt, asr_text)
                        
                        await websocket.send_text(f"PROMPT:{optimized_prompt}")
                        await websocket.send_text("GENERATING_IMAGE:正在生成图片，请稍候...")
                        
                        # 调用文生图API
                        image_path = await asyncio.to_thread(generate_image, optimized_prompt)
                        
                        if image_path and os.path.exists(image_path):
                            # 读取图片并发送回ESP32
                            with open(image_path, 'rb') as f:
                                image_data = f.read()
                            
                            print(f"Sending image to ESP32, size: {len(image_data)} bytes")
                            
                            # 使用hex编码发送（每个字节2个字符）
                            image_hex = image_data.hex()
                            await websocket.send_text(f"IMAGE_START:{len(image_data)}:{THUMB_SIZE}")
                            
                            # 分片发送图片数据
                            chunk_size = 1024
                            for i in range(0, len(image_hex), chunk_size):
                                chunk = image_hex[i:i+chunk_size]
                                await websocket.send_text(f"IMAGE_DATA:{chunk}")
                            
                            await websocket.send_text("IMAGE_END")
                            print("Image sent to ESP32")
                        else:
                            await websocket.send_text("IMAGE_ERROR:图片生成失败")
                    else:
                        print("No ASR text, skipping image generation")

                    print("Server processing finished.")
                    
                elif text.startswith("GET_FONTS_BATCH:"):
                    # Format: GET_FONTS_BATCH:code1,code2,code3 (decimal unicode)
                    try:
                        codes_str = text.split(":")[1]
                        code_list = codes_str.split(",")
                        print(f"Batch Font Request for {len(code_list)} chars: {code_list}")
                        
                        for code_str in code_list:
                            if not code_str: continue
                            
                            try:
                                unicode_val = int(code_str)
                                char = chr(unicode_val)
                                
                                gb_bytes = char.encode('gb2312')
                                if len(gb_bytes) == 2:
                                    code = struct.unpack('>H', gb_bytes)[0]
                                else:
                                    print(f"Character {char} is not a valid 2-byte GB2312 char")
                                    # Send empty/dummy? Or just skip.
                                    # Better to send something so client doesn't wait forever if it counts responses.
                                    # But client probably uses a set of missing chars.
                                    continue
                                
                                # Calc offset
                                area = (code >> 8) - 0xA0
                                index = (code & 0xFF) - 0xA0
                                
                                if area >= 1 and index >= 1:
                                    offset = ((area - 1) * 94 + (index - 1)) * 32
                                    
                                    # Read font file
                                    # Optimization: Open file once outside loop? 
                                    # For simplicity, keep it here, OS caching helps.
                                    
                                    script_dir = os.path.dirname(os.path.abspath(__file__))
                                    font_path = os.path.join(script_dir, FONT_FILE)
                                    if not os.path.exists(font_path):
                                        font_path = os.path.join(script_dir, "..", FONT_FILE)
                                    if not os.path.exists(font_path):
                                        font_path = FONT_FILE

                                    if os.path.exists(font_path):
                                        with open(font_path, "rb") as f:
                                            f.seek(offset)
                                            font_data = f.read(32)
                                            if len(font_data) == 32:
                                                import binascii
                                                hex_data = binascii.hexlify(font_data).decode('utf-8')
                                                response = f"FONT_DATA:{code_str}:{hex_data}"
                                                await websocket.send_text(response)
                                                # Small yield to let network flush?
                                                # await asyncio.sleep(0.001) 
                            except Exception as e:
                                print(f"Error processing batch item {code_str}: {e}")
                        
                        # Send a completion marker
                        await websocket.send_text("FONT_BATCH_END")
                        
                    except Exception as e:
                         print(f"Error handling BATCH FONT request: {e}")
                         await websocket.send_text("FONT_BATCH_END") # Ensure we unblock client

                elif text.startswith("GET_FONT_UNICODE:") or text.startswith("GET_FONT:"):
                    # 格式: GET_FONT_UNICODE:12345 (decimal) or GET_FONT:0xA1A1 (hex)
                    try:
                        is_unicode = text.startswith("GET_FONT_UNICODE:")
                        code_str = text.split(":")[1]
                        
                        target_code_str = code_str # Used for response
                        
                        if is_unicode:
                            unicode_val = int(code_str)
                            char = chr(unicode_val)
                            try:
                                gb_bytes = char.encode('gb2312')
                                if len(gb_bytes) == 2:
                                    code = struct.unpack('>H', gb_bytes)[0]
                                else:
                                    print(f"Character {char} is not a valid 2-byte GB2312 char")
                                    continue
                            except Exception as e:
                                print(f"Failed to encode {char} to gb2312: {e}")
                                continue
                        else:
                            code = int(code_str, 16)

                        # 计算偏移量
                        # GB2312 编码范围：0xA1A1 - 0xFEFE
                        # 区码：高字节 - 0xA0
                        # 位码：低字节 - 0xA0
                        area = (code >> 8) - 0xA0
                        index = (code & 0xFF) - 0xA0
                        
                        if area >= 1 and index >= 1:
                            offset = ((area - 1) * 94 + (index - 1)) * 32
                            
                            # 读取字体文件
                            # 注意：这里为了简单，每次都打开文件。如果并发高，应该缓存文件句柄或内容。
                            # 假设字体文件在当前目录或上级目录
                            # Prioritize finding the file in the script's directory
                            script_dir = os.path.dirname(os.path.abspath(__file__))
                            font_path = os.path.join(script_dir, FONT_FILE)
                            
                            # Fallback: check one level up
                            if not os.path.exists(font_path):
                                font_path = os.path.join(script_dir, "..", FONT_FILE)
                                
                            # Fallback: check current working directory
                            if not os.path.exists(font_path):
                                font_path = FONT_FILE
                            
                            if os.path.exists(font_path):
                                print(f"Reading font from: {font_path} (Offset: {offset})")
                                with open(font_path, "rb") as f:
                                    f.seek(offset)
                                    font_data = f.read(32)
                                    
                                    if len(font_data) == 32:
                                        import binascii
                                        hex_data = binascii.hexlify(font_data).decode('utf-8')
                                        # Return the original requested code (unicode or hex) so client can map it back
                                        response = f"FONT_DATA:{target_code_str}:{hex_data}"
                                        # print(f"Sending Font Response: {response[:30]}...")
                                        await websocket.send_text(response)
                                    else:
                                        print(f"Error: Read {len(font_data)} bytes for font data (expected 32)")
                            else:
                                print(f"Font file not found: {font_path}")
                        else:
                             print(f"Invalid GB2312 code derived: {code:X} (Area: {area}, Index: {index})")
                    except Exception as e:
                        print(f"Error handling FONT request: {e}")
            
            elif "bytes" in message:
                # 接收音频数据并追加到缓冲区
                data = message["bytes"]
                audio_buffer.extend(data)
                
                # 实时处理并发送给 ASR
                pcm_chunk = process_chunk_32_to_16(data, VOLUME_GAIN)
                processed_buffer.extend(pcm_chunk)
                
                if recognition:
                    try:
                        recognition.send_audio_frame(pcm_chunk)
                    except Exception as e:
                        print(f"Error sending audio frame to ASR: {e}")
                
    except WebSocketDisconnect:
        print("Client disconnected")
        if recognition:
            try:
                recognition.stop()
            except:
                pass
    except Exception as e:
        print(f"Error: {e}")
        if recognition:
            try:
                recognition.stop()
            except:
                pass

if __name__ == "__main__":
    # 获取本机IP，方便ESP32连接
    import socket
    hostname = socket.gethostname()
    local_ip = socket.gethostbyname(hostname)
    print(f"Server running on ws://{local_ip}:8000/ws/audio")
    
    uvicorn.run(app, host="0.0.0.0", port=8000)