from transformers import AutoModelForCausalLM, AutoTokenizer
from utils.logger import setup_logger
from utils.model_loader import ModelLoader
from api.shopify_client import ShopifyClient

logger = setup_logger(__name__)

class SQLGenerator:
    def __init__(self):
        try:
            self.model_name = "premai-io/prem-1B-SQL"
            self.tokenizer = ModelLoader.load_model_with_retry(
                self.model_name,
                AutoTokenizer
            )
            self.model = ModelLoader.load_model_with_retry(
                self.model_name,
                AutoModelForCausalLM
            )
            self.shopify_client = ShopifyClient()
        except Exception as e:
            logger.error(f"Failed to initialize SQLGenerator: {str(e)}")
            raise

    def generate_query(self, natural_language_query):
        try:
            schema_info = """
            CREATE TABLE products (
                id DECIMAL(8,2) PRIMARY KEY,
                title VARCHAR(255),
                body_html VARCHAR(255),
                vendor VARCHAR(255),
                product_type VARCHAR(255),
                created_at VARCHAR(255),
                handle VARCHAR(255),
                updated_at DATE,
                published_at VARCHAR(255),
                template_suffix VARCHAR(255),
                published_scope VARCHAR(255),
                tags VARCHAR(255),
                status VARCHAR(255),
                admin_graphql_api_id DECIMAL(8,2),
                variants VARCHAR(255),
                options VARCHAR(255),
                images VARCHAR(255),
                image VARCHAR(255)
            );
            """
            
            prompt = f"""### Task: Generate a SQL query to answer the following question.
            ### Database Schema: {schema_info}
            ### Question: {natural_language_query}
            ### SQL Query:"""
            
            inputs = self.tokenizer(prompt, return_tensors="pt", add_special_tokens=False)
            outputs = self.model.generate(
                inputs["input_ids"],
                max_length=256,
                do_sample=False,
                num_return_sequences=1,
                eos_token_id=self.tokenizer.eos_token_id,
                pad_token_id=self.tokenizer.pad_token_id
            )
            return self.tokenizer.decode(outputs[0], skip_special_tokens=True).strip()
        except Exception as e:
            logger.error(f"Query generation error: {str(e)}")
            return "Failed to generate SQL query due to an error."

    def fetch_shopify_data(self, endpoint):
        return self.shopify_client.fetch_data(endpoint)