import io
import re
import time
import asyncio
from typing import List, Optional
from gtts import gTTS
import edge_tts
from config.settings import settings
from models.schemas import TTSRequest

class EnhancedTTSService:
    def __init__(self):
        self.supported_languages = settings.SUPPORTED_LANGUAGES
        self.max_chunk_length = settings.MAX_CHUNK_LENGTH
    
    def detect_language(self, text: str) -> str:
        """Đơn giản phát hiện ngôn ngữ dựa trên ký tự"""
        vietnamese_chars = set('àáâãèéêìíòóôõùúýăđĩũơưạảấầẩẫậắằẳẵặẹẻẽếềểễệỉịọỏốồổỗộớờởỡợụủứừửữựỳỵỷỹ')
        if any(char in vietnamese_chars for char in text.lower()):
            return 'vi'
        elif any(char in text for char in 'あいうえお'):
            return 'ja'
        elif any(char in text for char in '你好'):
            return 'zh'
        elif any(char in text for char in '안녕'):
            return 'ko'
        else:
            return 'en'
    
    def split_text_into_chunks(self, text: str, max_length: int = None) -> List[str]:
        """Chia văn bản thành các đoạn nhỏ cho TTS"""
        if max_length is None:
            max_length = self.max_chunk_length
        
        sentences = re.split(r'[.!?]+', text)
        chunks = []
        current_chunk = ""
        
        for sentence in sentences:
            sentence = sentence.strip()
            if not sentence:
                continue
                
            if len(sentence) > max_length:
                parts = re.split(r'[,;:]', sentence)
                for part in parts:
                    part = part.strip()
                    if not part:
                        continue
                    if len(current_chunk) + len(part) + 2 <= max_length:
                        if current_chunk:
                            current_chunk += ". " + part
                        else:
                            current_chunk = part
                    else:
                        if current_chunk:
                            chunks.append(current_chunk)
                        current_chunk = part
            else:
                if len(current_chunk) + len(sentence) + 2 <= max_length:
                    if current_chunk:
                        current_chunk += ". " + sentence
                    else:
                        current_chunk = sentence
                else:
                    if current_chunk:
                        chunks.append(current_chunk)
                    current_chunk = sentence
        
        if current_chunk:
            chunks.append(current_chunk)
        
        return chunks
    
    def text_to_speech_gtts(self, text: str, language: str = 'vi') -> Optional[bytes]:
        """Sử dụng gTTS (Google Text-to-Speech) library"""
        try:
            chunks = self.split_text_into_chunks(text)
            audio_chunks = []
            
            for chunk in chunks:
                if not chunk.strip():
                    continue
                    
                tts = gTTS(text=chunk, lang=language, slow=False)
                audio_buffer = io.BytesIO()
                tts.write_to_fp(audio_buffer)
                audio_buffer.seek(0)
                audio_chunks.append(audio_buffer.read())
                
                time.sleep(0.1)
            
            if audio_chunks:
                return b''.join(audio_chunks)
            return None
            
        except Exception as e:
            print(f"❌ Lỗi gTTS: {e}")
            return None
    
    async def text_to_speech_edgetts(self, text: str, voice: str = 'vi-VN-NamMinhNeural') -> Optional[bytes]:
        """Sử dụng Edge-TTS (Microsoft Edge) - async version"""
        try:
            communicate = edge_tts.Communicate(text, voice)
            audio_buffer = io.BytesIO()
            
            async for chunk in communicate.stream():
                if chunk["type"] == "audio":
                    audio_buffer.write(chunk["data"])
            
            audio_buffer.seek(0)
            return audio_buffer.read()
            
        except Exception as e:
            print(f"❌ Lỗi Edge-TTS: {e}")
            return None
    
    def text_to_speech_edgetts_sync(self, text: str, voice: str = 'vi-VN-NamMinhNeural') -> Optional[bytes]:
        """Sync wrapper for Edge-TTS"""
        try:
            return asyncio.run(self.text_to_speech_edgetts(text, voice))
        except Exception as e:
            print(f"❌ Lỗi Edge-TTS sync: {e}")
            return None
    
    def text_to_speech(self, text: str, language: str = None, provider: str = "auto") -> Optional[bytes]:
        """Chuyển văn bản thành giọng nói với nhiều nhà cung cấp"""
        if not text or len(text.strip()) == 0:
            return None
        
        if language is None:
            language = self.detect_language(text)
        
        text = self.clean_text(text)
        
        try:
            if provider == "auto" or provider == "gtts":
                print(f"🔊 Đang sử dụng gTTS cho văn bản {len(text)} ký tự...")
                audio_bytes = self.text_to_speech_gtts(text, language)
                if audio_bytes:
                    return audio_bytes
            
            if provider == "auto" or provider == "edgetts":
                print(f"🔊 Đang thử Edge-TTS cho văn bản {len(text)} ký tự...")
                voice_map = {
                    'vi': 'vi-VN-NamMinhNeural',
                    'en': 'en-US-AriaNeural',
                    'fr': 'fr-FR-DeniseNeural',
                    'es': 'es-ES-ElviraNeural',
                    'de': 'de-DE-KatjaNeural',
                    'ja': 'ja-JP-NanamiNeural',
                    'ko': 'ko-KR-SunHiNeural',
                    'zh': 'zh-CN-XiaoxiaoNeural'
                }
                voice = voice_map.get(language, 'vi-VN-NamMinhNeural')
                audio_bytes = self.text_to_speech_edgetts_sync(text, voice)
                if audio_bytes:
                    return audio_bytes
            
            return self.text_to_speech_gtts(text, language)
            
        except Exception as e:
            print(f"❌ Lỗi TTS tổng hợp: {e}")
            return None
    
    def clean_text(self, text: str) -> str:
        """Làm sạch văn bản trước khi chuyển thành giọng nói"""
        text = re.sub(r'http\S+', '', text)
        text = re.sub(r'[^\w\sàáâãèéêìíòóôõùúýăđĩũơưạảấầẩẫậắằẳẵặẹẻẽếềểễệỉịọỏốồổỗộớờởỡợụủứừửữựỳỵỷỹ.,!?;:()-]', '', text)
        text = re.sub(r'\s+', ' ', text)
        return text.strip()
    
    def save_audio_to_file(self, audio_bytes: bytes, filename: str = None) -> str:
        """Lưu audio bytes thành file tạm thời"""
        if audio_bytes is None:
            return None
            
        if filename is None:
            filename = f"tts_output_{int(time.time())}.mp3"
            
        import os
        temp_dir = "temp_audio"
        os.makedirs(temp_dir, exist_ok=True)
        
        filepath = os.path.join(temp_dir, filename)
        with open(filepath, 'wb') as f:
            f.write(audio_bytes)
            
        return filepath
    def save_tts_audio(self, audio_bytes: bytes, filename: str = None) -> str:
        """Lưu audio bytes thành file tạm thời - tương thích với chat service"""
        if audio_bytes is None:
            return None
            
        if filename is None:
            import time
            filename = f"tts_output_{int(time.time())}.mp3"
            
        import os
        temp_dir = "temp_audio"
        os.makedirs(temp_dir, exist_ok=True)
        
        filepath = os.path.join(temp_dir, filename)
        with open(filepath, 'wb') as f:
            f.write(audio_bytes)
            
        return filepath