from dotenv import load_dotenv
import os
import json
import redis
from transformers import (
    AutoTokenizer,
    AutoModelForSequenceClassification,
    AutoModelForCausalLM,
    TrainingArguments,
    Trainer,
)
from fastapi import FastAPI, HTTPException, Request
from fastapi.responses import HTMLResponse
import multiprocessing
import time
import uuid

load_dotenv()

REDIS_HOST = os.getenv('REDIS_HOST')
REDIS_PORT = os.getenv('REDIS_PORT')
REDIS_PASSWORD = os.getenv('REDIS_PASSWORD')

app = FastAPI()

default_language = "es"

class ChatbotService:
    def __init__(self):
        self.redis_client = redis.StrictRedis(host=REDIS_HOST, port=REDIS_PORT, password=REDIS_PASSWORD, decode_responses=True)
        self.model_name = "response_model"
        self.tokenizer_name = "response_tokenizer"
        self.model = self.load_model_from_redis()
        self.tokenizer = self.load_tokenizer_from_redis()

    def get_response(self, user_id, message, language=default_language):
        if self.model is None or self.tokenizer is None:
            return "El modelo aún no está listo. Por favor, inténtelo de nuevo más tarde."
        input_text = f"Usuario: {message} Asistente:"
        input_ids = self.tokenizer.encode(input_text, return_tensors="pt").to("cpu")
        with torch.no_grad():
            output = self.model.generate(input_ids=input_ids, max_length=100, num_beams=5, no_repeat_ngram_size=2, early_stopping=True)
        response = self.tokenizer.decode(output[0], skip_special_tokens=True)
        response = response.replace(input_text, "").strip()
        return response

    def load_model_from_redis(self):
        model_data_bytes = self.redis_client.get(f"model:{self.model_name}")
        if model_data_bytes:
            model = AutoModelForCausalLM.from_pretrained("gpt2")
            model.load_state_dict(torch.load(model_data_bytes))
            return model
        return None

    def load_tokenizer_from_redis(self):
        tokenizer_data_bytes = self.redis_client.get(f"tokenizer:{self.tokenizer_name}")
        if tokenizer_data_bytes:
            tokenizer = AutoTokenizer.from_pretrained("gpt2")
            tokenizer.add_tokens(json.loads(tokenizer_data_bytes))
            tokenizer.pad_token = tokenizer.eos_token
            return tokenizer
        return None

chatbot_service = ChatbotService()

class UnifiedModel(AutoModelForSequenceClassification):
    def __init__(self, config):
        super().__init__(config)

    @staticmethod
    def load_model_from_redis(redis_client):
        model_name = "unified_model"
        model_path = f"models/{model_name}"
        if redis_client.exists(f"model:{model_name}"):
            redis_client.delete(f"model:{model_name}")
        if not os.path.exists(model_path):
            model = UnifiedModel.from_pretrained("gpt2", num_labels=3)
            model.save_pretrained(model_path)
        else:
            model = UnifiedModel.from_pretrained(model_path)
        return model

class SyntheticDataset(Dataset):
    def __init__(self, tokenizer, data):
        self.tokenizer = tokenizer
        self.data = data

    def __len__(self):
        return len(self.data)

    def __getitem__(self, idx):
        item = self.data[idx]
        text = item['text']
        label = item['label']
        tokens = self.tokenizer(text, padding="max_length", truncation=True, max_length=128, return_tensors="pt")
        return {"input_ids": tokens["input_ids"].squeeze(), "attention_mask": tokens["attention_mask"].squeeze(), "labels": label}

conversation_history = {}

@app.post("/process")
async def process(request: Request):
    data = await request.json()
    redis_client = redis.StrictRedis(host=REDIS_HOST, port=REDIS_PORT, password=REDIS_PASSWORD, decode_responses=True)

    tokenizer_name = "unified_tokenizer"

    tokenizer_data_bytes = redis_client.get(f"tokenizer:{tokenizer_name}")

    if tokenizer_data_bytes:
        tokenizer = AutoTokenizer.from_pretrained("gpt2")
        tokenizer.add_tokens(json.loads(tokenizer_data_bytes))
        tokenizer.pad_token = tokenizer.eos_token
    else:
        tokenizer = AutoTokenizer.from_pretrained("gpt2")
        tokenizer.pad_token = tokenizer.eos_token

    unified_model = UnifiedModel.load_model_from_redis(redis_client)
    unified_model.to(torch.device("cpu"))

    if data.get("train"):
        user_data = data.get("user_data", [])
        if not user_data:
            user_data = [
                {"text": "Hola", "label": 1},
                {"text": "Necesito ayuda", "label": 2},
                {"text": "No entiendo", "label": 0}
            ]
        redis_client.rpush("training_queue", json.dumps({
            "tokenizers": {tokenizer_name: tokenizer.get_vocab()},
            "data": user_data
        }))
        return {"message": "Training data received. Model will be updated asynchronously."}
    elif data.get("message"):
        user_id = data.get("user_id")
        text = data['message']
        language = data.get("language", default_language)
        if user_id not in conversation_history:
            conversation_history[user_id] = []
        conversation_history[user_id].append(text)
        contextualized_text = " ".join(conversation_history[user_id][-3:])
        tokenized_input = tokenizer(contextualized_text, return_tensors="pt")
        with torch.no_grad():
            logits = unified_model(**tokenized_input).logits
            predicted_class = torch.argmax(logits, dim=-1).item()
        response = chatbot_service.get_response(user_id, contextualized_text, language)
        redis_client.rpush("training_queue", json.dumps({
            "tokenizers": {tokenizer_name: tokenizer.get_vocab()},
            "data": [{"text": contextualized_text, "label": predicted_class}]
        }))
        return {"answer": response}
    else:
        raise HTTPException(status_code=400, detail="Request must contain 'train' or 'message'.")

@app.get("/")
async def get_home():
    user_id = str(uuid.uuid4())
    html_code = f"""
    <!DOCTYPE html>
    <html>
    <head>
        <meta charset="UTF-8">
        <title>Chatbot</title>
        <style>
            body {{
                font-family: 'Arial', sans-serif;
                background-color: #f4f4f9;
                margin: 0;
                padding: 0;
                display: flex;
                align-items: center;
                justify-content: center;
                min-height: 100vh;
            }}
            .container {{
                background-color: #fff;
                border-radius: 10px;
                box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
                overflow: hidden;
                width: 400px;
                max-width: 90%;
            }}
            h1 {{
                color: #333;
                text-align: center;
                padding: 20px;
                margin: 0;
                background-color: #f8f9fa;
                border-bottom: 1px solid #eee;
            }}
            #chatbox {{
                height: 300px;
                overflow-y: auto;
                padding: 10px;
                border-bottom: 1px solid #eee;
            }}
            .message {{
                margin-bottom: 10px;
                padding: 10px;
                border-radius: 5px;
            }}
            .message.user {{
                background-color: #e1f5fe;
                text-align: right;
            }}
            .message.bot {{
                background-color: #f1f1f1;
                text-align: left;
            }}
            #input {{
                display: flex;
                padding: 10px;
            }}
            #input textarea {{
                flex: 1;
                padding: 10px;
                border: 1px solid #ddd;
                border-radius: 4px;
                margin-right: 10px;
            }}
            #input button {{
                padding: 10px 20px;
                border: none;
                border-radius: 4px;
                background-color: #007bff;
                color: #fff;
                cursor: pointer;
            }}
            #input button:hover {{
                background-color: #0056b3;
            }}
        </style>
    </head>
    <body>
        <div class="container">
            <h1>Chatbot</h1>
            <div id="chatbox"></div>
            <div id="input">
                <textarea id="message" rows="3" placeholder="Escribe tu mensaje aquí..."></textarea>
                <button id="send">Enviar</button>
            </div>
        </div>
        <script>
            const chatbox = document.getElementById('chatbox');
            const messageInput = document.getElementById('message');
            const sendButton = document.getElementById('send');

            function appendMessage(text, sender) {{
                const messageDiv = document.createElement('div');
                messageDiv.classList.add('message', sender);
                messageDiv.textContent = text;
                chatbox.appendChild(messageDiv);
                chatbox.scrollTop = chatbox.scrollHeight;
            }}

            async function sendMessage() {{
                const message = messageInput.value;
                if (!message.trim()) return;

                appendMessage(message, 'user');
                messageInput.value = '';

                const response = await fetch('/process', {{
                    method: 'POST',
                    headers: {{
                        'Content-Type': 'application/json'
                    }},
                    body: JSON.stringify({{
                        message: message,
                        user_id: '{user_id}'
                    }})
                }});
                const data = await response.json();
                appendMessage(data.answer, 'bot');
            }}

            sendButton.addEventListener('click', sendMessage);
            messageInput.addEventListener('keypress', (e) => {{
                if (e.key === 'Enter' && !e.shiftKey) {{
                    e.preventDefault();
                    sendMessage();
                }}
            }});
        </script>
    </body>
    </html>
    """
    return HTMLResponse(content=html_code)

def train_unified_model():
    redis_client = redis.StrictRedis(host=REDIS_HOST, port=REDIS_PORT, password=REDIS_PASSWORD, decode_responses=True)
    while True:
        training_queue = redis_client.lrange("training_queue", 0, -1)
        if training_queue:
            for item in training_queue:
                item_data = json.loads(item)
                tokenizer_data = item_data["tokenizers"]
                tokenizer_name = list(tokenizer_data.keys())[0]
                tokenizer = AutoTokenizer.from_pretrained("gpt2")
                tokenizer.add_tokens(json.loads(tokenizer_data[tokenizer_name]))
                tokenizer.pad_token = tokenizer.eos_token
                data = item_data["data"]
                dataset = SyntheticDataset(tokenizer, data)

                model_name = "unified_model"
                model_path = f"models/{model_name}"
                model = UnifiedModel.from_pretrained(model_path)
                
                training_args = TrainingArguments(
                    output_dir="./results",
                    per_device_train_batch_size=8,
                    num_train_epochs=3,
                )
                trainer = Trainer(model=model, args=training_args, train_dataset=dataset)
                trainer.train()
                model.save_pretrained(model_path)
                redis_client.delete("training_queue")
        time.sleep(60)

if __name__ == "__main__":
    training_process = multiprocessing.Process(target=train_unified_model)
    training_process.start()
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=7860)