"""
FetcherPay API Client
"""

import hmac
import hashlib
from typing import Optional
import requests
from requests.adapters import HTTPAdapter
from urllib.parse import urljoin

from .exceptions import (
    FetcherPayError,
    AuthenticationError,
    ValidationError,
    NotFoundError,
    IdempotencyError,
)
from .api.payments import PaymentsAPI
from .api.ledger import LedgerAPI
from .api.payment_methods import PaymentMethodsAPI
from .api.webhooks import WebhooksAPI


class FetcherPay:
    """
    Main FetcherPay client
    
    Args:
        api_key: Your FetcherPay API key
        environment: 'sandbox' or 'production'
        base_url: Optional custom base URL
        timeout: Request timeout in seconds (default: 30)
    """
    
    def __init__(
        self,
        api_key: str,
        environment: str = 'sandbox',
        base_url: Optional[str] = None,
        timeout: int = 30
    ):
        self.api_key = api_key
        self.environment = environment
        self.timeout = timeout
        
        if base_url:
            self.base_url = base_url
        elif environment == 'production':
            self.base_url = 'https://api.fetcherpay.com/v1'
        else:
            self.base_url = 'https://sandbox.fetcherpay.com/v1'
        
        # Create session with retries
        self.session = requests.Session()
        self.session.headers.update({
            'Authorization': f'Bearer {api_key}',
            'Content-Type': 'application/json',
        })
        
        # Initialize API modules
        self.payments = PaymentsAPI(self)
        self.ledger = LedgerAPI(self)
        self.payment_methods = PaymentMethodsAPI(self)
        self.webhooks = WebhooksAPI(self)
    
    def _request(
        self,
        method: str,
        path: str,
        params: Optional[dict] = None,
        json: Optional[dict] = None,
        headers: Optional[dict] = None,
        idempotency_key: Optional[str] = None
    ) -> dict:
        """Make an HTTP request"""
        url = urljoin(self.base_url, path)
        
        request_headers = {}
        if headers:
            request_headers.update(headers)
        if idempotency_key:
            request_headers['Idempotency-Key'] = idempotency_key
        
        try:
            response = self.session.request(
                method=method,
                url=url,
                params=params,
                json=json,
                headers=request_headers,
                timeout=self.timeout
            )
            
            # Handle errors
            if response.status_code >= 400:
                self._handle_error(response)
            
            return response.json() if response.content else {}
            
        except requests.exceptions.Timeout:
            raise FetcherPayError('Request timeout', 'timeout_error')
        except requests.exceptions.ConnectionError:
            raise FetcherPayError('Connection error', 'connection_error')
    
    def _handle_error(self, response):
        """Handle API errors"""
        try:
            data = response.json()
            error = data.get('error', {})
        except:
            error = {}
        
        message = error.get('message', 'An error occurred')
        error_type = error.get('type', 'api_error')
        param = error.get('param')
        code = error.get('code')
        
        if response.status_code == 401:
            raise AuthenticationError(message)
        elif response.status_code == 404:
            raise NotFoundError(message)
        elif response.status_code == 422:
            raise ValidationError(message, param)
        elif response.status_code == 409:
            raise IdempotencyError(message)
        else:
            raise FetcherPayError(message, error_type, response.status_code, param, code)
    
    def verify_webhook_signature(
        self,
        payload: str,
        signature: str,
        secret: str
    ) -> bool:
        """
        Verify a webhook signature
        
        Args:
            payload: The raw webhook payload string
            signature: The signature from X-FetcherPay-Signature header
            secret: Your webhook secret
        
        Returns:
            True if signature is valid
        """
        expected = hmac.new(
            secret.encode('utf-8'),
            payload.encode('utf-8'),
            hashlib.sha256
        ).hexdigest()
        
        return hmac.compare_digest(signature, expected)