import os
import json
import sys
from dotenv import load_dotenv

# Load environment variables from .env file if it exists
load_dotenv()

# Check for required environment variables and provide guidance if missing
required_vars = ["OPENAI_API_KEY", "PROJECT_ID", "DATASET_ID", "BIGQUERY_KEY_PATH"]
missing_vars = [var for var in required_vars if not os.environ.get(var)]

if missing_vars:
    print("ERROR: Missing required environment variables:")
    for var in missing_vars:
        print(f"- {var}")
    print("\nPlease set these variables in your environment or in a .env file.")
    print("Example .env file:")
    print("""
    OPENAI_API_KEY=your_openai_api_key
    PROJECT_ID=your_gcp_project_id
    DATASET_ID=your_bigquery_dataset_id
    BIGQUERY_KEY_PATH=path/to/your/bigquery/credentials.json
    """)

# Handle BigQuery credentials
print("DEBUG: Handling BigQuery credentials...")

if os.environ.get("BIGQUERY_KEY_PATH"):
    bigquery_key = os.environ.get("BIGQUERY_KEY_PATH")
    print(f"DEBUG: BIGQUERY_KEY_PATH is set, length: {len(bigquery_key)} characters")
    print(f"DEBUG: First 20 chars: {bigquery_key[:20]}...")
    
    # If BIGQUERY_KEY_PATH contains the actual JSON content (as in HF Spaces secrets)
    if bigquery_key.strip().startswith("{"):
        print("DEBUG: BIGQUERY_KEY_PATH appears to contain JSON content")
        try:
            # Validate JSON
            json_obj = json.loads(bigquery_key)
            print("DEBUG: Successfully parsed JSON content")
            
            # Create a temporary credentials file from the environment variable
            credentials_path = "/tmp/bigquery_credentials.json"
            
            with open(credentials_path, "w") as f:
                f.write(bigquery_key)
            
            print(f"DEBUG: Wrote credentials to {credentials_path}")
            
            # Set the credentials path to the temporary file
            os.environ["GOOGLE_APPLICATION_CREDENTIALS"] = credentials_path
            print(f"DEBUG: Set GOOGLE_APPLICATION_CREDENTIALS to {credentials_path}")
            
            # Verify the file exists
            if os.path.exists(credentials_path):
                print(f"DEBUG: Confirmed credentials file exists at {credentials_path}")
                with open(credentials_path, "r") as f:
                    first_line = f.readline()
                    print(f"DEBUG: First line of credentials file: {first_line[:20]}...")
            else:
                print(f"ERROR: Failed to create credentials file at {credentials_path}")
        except json.JSONDecodeError as e:
            print(f"ERROR: BIGQUERY_KEY_PATH contains invalid JSON: {str(e)}")
            print("Please ensure your secret contains valid JSON content")
    # If BIGQUERY_KEY_PATH is a file path
    elif os.path.exists(bigquery_key):
        print(f"DEBUG: BIGQUERY_KEY_PATH points to existing file: {bigquery_key}")
        os.environ["GOOGLE_APPLICATION_CREDENTIALS"] = bigquery_key
    else:
        print(f"WARNING: BIGQUERY_KEY_PATH is set but does not contain JSON and is not a valid file path: {bigquery_key}")
else:
    print("WARNING: BIGQUERY_KEY_PATH environment variable is not set")

# BigQuery configuration
BIGQUERY_KEY_PATH = os.environ.get("BIGQUERY_KEY_PATH")
PROJECT_ID = os.environ.get("PROJECT_ID")
DATASET_ID = os.environ.get("DATASET_ID")

# Final check for GOOGLE_APPLICATION_CREDENTIALS
if os.environ.get("GOOGLE_APPLICATION_CREDENTIALS"):
    print(f"DEBUG: GOOGLE_APPLICATION_CREDENTIALS is set to: {os.environ.get('GOOGLE_APPLICATION_CREDENTIALS')}")
    if os.path.exists(os.environ.get("GOOGLE_APPLICATION_CREDENTIALS")):
        print("DEBUG: GOOGLE_APPLICATION_CREDENTIALS file exists")
    else:
        print("ERROR: GOOGLE_APPLICATION_CREDENTIALS file does not exist")
else:
    print("WARNING: GOOGLE_APPLICATION_CREDENTIALS is not set")