"""
Google Cloud CDN Core Implementation

Core attributes and authentication for Google Cloud CDN.
Provides the foundation for the modular content delivery network.
"""

from typing import Dict, Any, List, Optional, Union
from ..base_resource import BaseGcpResource


class CloudCdnCore(BaseGcpResource):
    """
    Core class for Google Cloud CDN functionality.
    
    This class provides:
    - Basic Cloud CDN attributes and configuration
    - Authentication setup
    - Common utilities for CDN operations
    - Validation and state tracking foundations
    """
    
    def __init__(self, name: str):
        """
        Initialize Cloud CDN core with CDN name.
        
        Args:
            name: CDN configuration name
        """
        super().__init__(name)
        
        # Core CDN attributes
        self.cdn_name = name
        self.cdn_description = f"Cloud CDN configuration: {name}"
        self.cdn_type = "cloud_cdn"
        
        # CDN configuration
        self.project_id = None
        self.enabled = True
        self.negative_caching = True
        self.negative_caching_policy = []
        
        # Cache configuration
        self.cache_mode = "CACHE_ALL_STATIC"
        self.default_ttl = 3600  # 1 hour
        self.max_ttl = 86400     # 24 hours
        self.client_ttl = 3600   # 1 hour
        self.serve_while_stale = 86400  # 24 hours
        
        # Compression configuration
        self.compression_mode = "AUTOMATIC"
        
        # Security configuration
        self.signed_url_cache_max_age = 3600
        self.bypass_cache_on_request_headers = []
        
        # Backend configuration
        self.backend_service = None
        self.backend_bucket = None
        
        # Path matcher configuration
        self.url_map = None
        self.path_matchers = []
        self.default_service = None
        
        # Cache key policy
        self.cache_key_policy = {
            "include_protocol": True,
            "include_host": True,
            "include_query_string": True,
            "query_string_whitelist": [],
            "query_string_blacklist": [],
            "include_http_headers": [],
            "include_named_cookies": []
        }
        
        # Origin configuration
        self.origin_override = None
        self.origin_redirect = False
        
        # State tracking
        self.cdn_exists = False
        self.cdn_created = False
        self.cdn_state = None
        self.deployment_status = None
        
        # Labels and metadata
        self.cdn_labels = {}
        self.cdn_annotations = {}
        
        # Cost tracking
        self.estimated_monthly_cost = "$50.00/month"
        
    def _initialize_managers(self):
        """Initialize CDN specific managers"""
        self.compute_client = None
        
    def _post_authentication_setup(self):
        """Setup managers after authentication"""
        try:
            from google.cloud import compute_v1
            
            self.compute_client = compute_v1.BackendServicesClient()
            
            # Set project ID from GCP client if available
            if hasattr(self.gcp_client, 'project'):
                self.project_id = self.gcp_client.project
                
        except Exception as e:
            print(f"⚠️  Cloud CDN setup note: {str(e)}")
            
    def _validate_cache_mode(self, cache_mode: str) -> bool:
        """Validate if cache mode is valid"""
        valid_modes = [
            "USE_ORIGIN_HEADERS",
            "FORCE_CACHE_ALL",
            "CACHE_ALL_STATIC"
        ]
        return cache_mode in valid_modes
        
    def _validate_ttl(self, ttl: int) -> bool:
        """Validate TTL values"""
        return 0 <= ttl <= 2592000  # 0 to 30 days
        
    def _validate_compression_mode(self, compression_mode: str) -> bool:
        """Validate compression mode"""
        valid_modes = [
            "AUTOMATIC",
            "DISABLED"
        ]
        return compression_mode in valid_modes
        
    def _get_cdn_type_from_config(self) -> str:
        """Determine CDN type from configuration"""
        # Check by backend type
        if self.backend_service and self.backend_bucket:
            return "hybrid_cdn"
        elif self.backend_service:
            return "compute_cdn"
        elif self.backend_bucket:
            return "storage_cdn"
            
        # Check by cache configuration
        if self.cache_mode == "FORCE_CACHE_ALL":
            return "aggressive_caching"
        elif self.cache_mode == "USE_ORIGIN_HEADERS":
            return "origin_controlled"
        else:
            return "standard_cdn"
            
    def _estimate_cdn_cost(self) -> float:
        """Estimate monthly cost for Cloud CDN"""
        # Cloud CDN pricing (simplified)
        
        # Cache fill charges (estimated 100GB origin traffic per month)
        cache_fill_gb = 100
        cache_fill_cost = cache_fill_gb * 0.085  # $0.085/GB for cache fill
        
        # Cache egress charges (estimated 1TB served per month)
        cache_egress_gb = 1000
        
        # Tiered pricing for cache egress
        if cache_egress_gb <= 10000:  # First 10TB
            egress_cost = cache_egress_gb * 0.04  # $0.04/GB
        else:
            egress_cost = (10000 * 0.04) + ((cache_egress_gb - 10000) * 0.035)
            
        # HTTP/HTTPS requests (estimated 10M requests per month)
        requests_millions = 10
        request_cost = requests_millions * 0.0075  # $0.0075 per 10,000 requests
        
        # Invalidation requests (estimated 1000 per month)
        invalidations = 1000
        invalidation_cost = max(0, invalidations - 1000) * 0.005  # First 1000 free
        
        total_cost = cache_fill_cost + egress_cost + request_cost + invalidation_cost
        
        return total_cost
        
    def _fetch_current_cdn_state(self) -> Dict[str, Any]:
        """Fetch current state of CDN configuration"""
        try:
            if not self.compute_client or not self.project_id:
                return {
                    "exists": False,
                    "cdn_name": self.cdn_name,
                    "error": "Compute client not initialized or no project ID"
                }
                
            # For CDN, we check backend services and URL maps
            # This is a simplified check - real implementation would check specific CDN resources
            return {
                "exists": False,  # Simplified for now
                "cdn_name": self.cdn_name,
                "project_id": self.project_id,
                "reason": "CDN state check simplified"
            }
            
        except Exception as e:
            return {
                "exists": False,
                "cdn_name": self.cdn_name,
                "error": str(e)
            }
            
    def _discover_existing_cdns(self) -> Dict[str, Dict[str, Any]]:
        """Discover existing CDN configurations in the project"""
        existing_cdns = {}
        
        try:
            if not self.compute_client or not self.project_id:
                return existing_cdns
                
            # This would typically list backend services with CDN enabled
            # Simplified for now
            print(f"⚠️  CDN discovery not yet implemented in simplified version")
            
        except Exception as e:
            print(f"⚠️  Failed to discover existing CDNs: {str(e)}")
            
        return existing_cdns