"""
Configuration loading and validation module
"""

import json
import os
from pathlib import Path
from typing import Dict, Any, Optional
from pydantic import BaseModel, Field
from dotenv import load_dotenv


class DatabaseConfig(BaseModel):
    url: str
    echo: bool = False
    pool_size: int = 5
    max_overflow: int = 10


class AIServiceConfig(BaseModel):
    provider: str = "openrouter"
    base_url: str = "https://openrouter.ai/api/v1"
    model: str = "anthropic/claude-3.5-sonnet"
    max_tokens: int = 4000
    temperature: float = 0.7
    timeout: int = 30
    available_models: Dict[str, str] = Field(default_factory=dict)


class UniversalRulesConfig(BaseModel):
    min_content_length: int = 1000
    max_content_length: int = 5000
    word_count_tolerance: int = 10
    default_term_frequency: int = 2
    title_exact_match_required: bool = True
    h1_exact_match_required: bool = True
    h2_exact_match_min: int = 1
    h3_exact_match_min: int = 1
    faq_section_required: bool = True
    faq_question_restatement_required: bool = True
    image_alt_text_keyword_required: bool = True
    image_alt_text_entity_required: bool = True


class CORAValidationConfig(BaseModel):
    enabled: bool = True
    tier_1_strict: bool = True
    tier_2_plus_warn_only: bool = True
    round_averages_down: bool = True


class ContentRulesConfig(BaseModel):
    universal: UniversalRulesConfig
    cora_validation: CORAValidationConfig


class TemplateConfig(BaseModel):
    default: str = "basic"
    mappings: Dict[str, str] = Field(default_factory=dict)


class DeploymentConfig(BaseModel):
    providers: Dict[str, Dict[str, Any]] = Field(default_factory=dict)


class InterlinkingConfig(BaseModel):
    wheel_links: bool = True
    home_page_link: bool = True
    random_article_link: bool = True
    max_links_per_article: int = 5


class LoggingConfig(BaseModel):
    level: str = "INFO"
    format: str = "json"
    file: str = "logs/app.log"
    max_size: str = "10MB"
    backup_count: int = 5


class APIConfig(BaseModel):
    host: str = "0.0.0.0"
    port: int = 8000
    reload: bool = True
    workers: int = 1


class ApplicationConfig(BaseModel):
    name: str
    version: str
    environment: str


class Config(BaseModel):
    application: ApplicationConfig
    database: DatabaseConfig
    ai_service: AIServiceConfig
    content_rules: ContentRulesConfig
    templates: TemplateConfig
    deployment: DeploymentConfig
    interlinking: InterlinkingConfig
    logging: LoggingConfig
    api: APIConfig
    
    def get(self, key: str, default: Any = None) -> Any:
        """Get config value using dot notation (e.g., 'content_rules.universal')"""
        try:
            parts = key.split('.')
            value = self
            for part in parts:
                if hasattr(value, part):
                    value = getattr(value, part)
                else:
                    return default
            
            if isinstance(value, BaseModel):
                return value.model_dump()
            return value
        except Exception:
            return default


class ConfigManager:
    """Manages application configuration loading and validation"""
    
    def __init__(self, config_path: Optional[str] = None):
        self.config_path = config_path or "master.config.json"
        self._config: Optional[Config] = None
        
    def load_config(self) -> Config:
        """Load and validate configuration from JSON file"""
        if self._config is None:
            # Load environment variables first
            load_dotenv()
            
            # Load JSON configuration
            config_path = Path(self.config_path)
            if not config_path.exists():
                raise FileNotFoundError(f"Configuration file not found: {config_path}")
            
            with open(config_path, 'r') as f:
                config_data = json.load(f)
            
            # Override with environment variables where applicable
            self._override_with_env(config_data)
            
            # Validate configuration
            self._config = Config(**config_data)
        
        return self._config
    
    def _override_with_env(self, config_data: Dict[str, Any]) -> None:
        """Override configuration with environment variables"""
        # Database URL
        if os.getenv("DATABASE_URL"):
            config_data["database"]["url"] = os.getenv("DATABASE_URL")
        
        # AI Service configuration
        if os.getenv("AI_API_KEY"):
            # Note: API key is handled separately for security
            pass
        if os.getenv("AI_API_BASE_URL"):
            config_data["ai_service"]["base_url"] = os.getenv("AI_API_BASE_URL")
        if os.getenv("AI_MODEL"):
            config_data["ai_service"]["model"] = os.getenv("AI_MODEL")
        
        # Logging level
        if os.getenv("LOG_LEVEL"):
            config_data["logging"]["level"] = os.getenv("LOG_LEVEL")
        
        # Environment
        if os.getenv("ENVIRONMENT"):
            config_data["application"]["environment"] = os.getenv("ENVIRONMENT")
    
    def get_config(self) -> Config:
        """Get the current configuration"""
        if self._config is None:
            return self.load_config()
        return self._config
    
    def reload_config(self) -> Config:
        """Reload configuration from file"""
        self._config = None
        return self.load_config()


# Global configuration instance
config_manager = ConfigManager()


def get_config() -> Config:
    """Get the application configuration"""
    return config_manager.get_config()


def reload_config() -> Config:
    """Reload the application configuration"""
    return config_manager.reload_config()


def get_ai_api_key() -> str:
    """Get the AI API key from environment variables"""
    api_key = os.getenv("AI_API_KEY")
    if not api_key:
        raise ValueError("AI_API_KEY environment variable is required")
    return api_key


def get_bunny_account_api_key() -> str:
    """Get the bunny.net Account API key from environment variables"""
    api_key = os.getenv("BUNNY_ACCOUNT_API_KEY")
    if not api_key:
        raise ValueError("BUNNY_ACCOUNT_API_KEY environment variable is required")
    return api_key