import secrets
import hashlib
from typing import Optional, Dict, Tuple
from app.utils import read_json, write_json
from pathlib import Path

class DatabaseAPIKeyManager:
    """Manage per-database API keys with secret key authentication"""
    
    def __init__(self):
        pass
    
    def _generate_pair(self) -> Tuple[str, str, str]:
        """Generate api_key (CDB- prefix), secret (NNNN-NNNN-NNNN numeric), and secret_hash."""
        api_key = f"CDB-{secrets.token_urlsafe(24)[:32]}"
        secret_key = '-'.join(str(secrets.randbelow(10000)).zfill(4) for _ in range(3))
        secret_hash = hashlib.sha256(secret_key.encode()).hexdigest()
        return api_key, secret_key, secret_hash

    def generate_db_api_key(self, workspace_id: str, database: str) -> str:
        """Legacy single-value generator — use generate_db_api_key_with_secret for new keys"""
        return f"CDB-{secrets.token_urlsafe(24)[:32]}"
    
    def store_db_api_key(self, user_store, database: str, api_key: str, secret_hash: str = '', workspace_id: str = '') -> Dict:
        """Store database API key and secret hash"""
        keys_file = user_store.local("metadata", "db_api_keys.json")
        keys = read_json(keys_file, {})
        keys[database] = {
            'api_key': api_key,
            'secret_hash': secret_hash,
            'workspace_id': workspace_id,
            'database': database,
            'created_at': self._utc_now(),
            'last_used': None,
            'usage_count': 0
        }
        write_json(keys_file, keys)
        user_store.upload_file(keys_file, "metadata/db_api_keys.json", f"Create API key for {database}")
        return keys[database]

    def create_db_api_key(self, user_store, database: str, workspace_id: str = '') -> Dict:
        """Generate, store, and return api_key + secret_key (plaintext shown once)"""
        api_key, secret_key, secret_hash = self._generate_pair()
        self.store_db_api_key(user_store, database, api_key, secret_hash, workspace_id)
        return {'api_key': api_key, 'secret_key': secret_key}

    def get_db_api_key(self, user_store, database: str) -> Optional[str]:
        """Get API key for a database"""
        keys_file = user_store.local("metadata", "db_api_keys.json")
        keys = read_json(keys_file, {})
        if database in keys:
            return keys[database]['api_key']
        return None
    
    def verify_db_api_key(self, user_store, api_key: str, secret_key: str) -> Optional[Dict]:
        """Verify database API key + secret. Returns {database, workspace_id} or None."""
        keys_file = user_store.local("metadata", "db_api_keys.json")
        keys = read_json(keys_file, {})
        secret_hash = hashlib.sha256(secret_key.encode()).hexdigest()
        for database, key_info in keys.items():
            if key_info['api_key'] != api_key:
                continue
            stored_hash = key_info.get('secret_hash', '')
            if stored_hash and stored_hash != secret_hash:
                continue
            key_info['last_used'] = self._utc_now()
            key_info['usage_count'] = key_info.get('usage_count', 0) + 1
            write_json(keys_file, keys)
            return {'database': database, 'workspace_id': key_info.get('workspace_id', '')}
        return None
    
    def regenerate_db_api_key(self, user_store, workspace_id: str, database: str) -> Dict:
        """Regenerate API key + secret for a database. Returns new api_key + secret_key (shown once)"""
        api_key, secret_key, secret_hash = self._generate_pair()
        self.store_db_api_key(user_store, database, api_key, secret_hash)
        return {'api_key': api_key, 'secret_key': secret_key}
    
    def revoke_db_api_key(self, user_store, database: str) -> bool:
        """Revoke API key for a database"""
        keys_file = user_store.local("metadata", "db_api_keys.json")
        keys = read_json(keys_file, {})
        
        if database in keys:
            del keys[database]
            write_json(keys_file, keys)
            user_store.upload_file(keys_file, "metadata/db_api_keys.json", f"Revoke API key for {database}")
            return True
        
        return False
    
    def list_db_api_keys(self, user_store) -> Dict:
        """List all database API keys"""
        keys_file = user_store.local("metadata", "db_api_keys.json")
        return read_json(keys_file, {})
    
    def get_connection_string(self, base_url: str, database: str, api_key: str) -> Dict:
        """Generate connection string for a database"""
        return {
            'database': database,
            'api_endpoint': f"{base_url}/api/db/{database}",
            'api_key': api_key,
            'websocket': f"{base_url.replace('http', 'ws')}/ws?db={database}&key={api_key}",
            'examples': {
                'python': f'''import requests

BASE_URL = "{base_url}/api/db/{database}"
HEADERS = {{"X-Database-Key": "{api_key}"}}

# Query data
response = requests.get(f"{{BASE_URL}}/query", 
    params={{"sql": "SELECT * FROM my_table LIMIT 10"}},
    headers=HEADERS)
data = response.json()

# Insert data
response = requests.post(f"{{BASE_URL}}/insert",
    json={{"table": "my_table", "data": {{"id": 1, "name": "John"}}}},
    headers=HEADERS)
''',
                'javascript': f'''const BASE_URL = '{base_url}/api/db/{database}';
const HEADERS = {{ 'X-Database-Key': '{api_key}' }};

// Query data
fetch(`${{BASE_URL}}/query?sql=SELECT * FROM my_table LIMIT 10`, {{
  headers: HEADERS
}})
.then(res => res.json())
.then(data => console.log(data));

// Insert data
fetch(`${{BASE_URL}}/insert`, {{
  method: 'POST',
  headers: {{ ...HEADERS, 'Content-Type': 'application/json' }},
  body: JSON.stringify({{
    table: 'my_table',
    data: {{ id: 1, name: 'John' }}
  }})
}});
''',
                'curl': f'''# Query data
curl "{base_url}/api/db/{database}/query?sql=SELECT%20*%20FROM%20my_table%20LIMIT%2010" \\
  -H "X-Database-Key: {api_key}"

# Insert data
curl -X POST "{base_url}/api/db/{database}/insert" \\
  -H "X-Database-Key: {api_key}" \\
  -H "Content-Type: application/json" \\
  -d '{{"table": "my_table", "data": {{"id": 1, "name": "John"}}}}'
'''
            }
        }
    
    def _utc_now(self):
        from datetime import datetime
        return datetime.utcnow().isoformat()

db_api_key_manager = DatabaseAPIKeyManager()