"""
Configuration management for TreeTrack - Supabase Edition
Environment-based configuration for cloud deployment
"""

import os
from functools import lru_cache
from pathlib import Path
from typing import List, Optional

from pydantic import Field, field_validator
from pydantic_settings import BaseSettings


class SecurityConfig(BaseSettings):
    """Security configuration settings"""
    
    # CORS settings for web deployment
    cors_origins: List[str] = Field(
        default=["*"], env="CORS_ORIGINS"  # Allow all origins for HuggingFace Spaces
    )
    
    # Request limits
    max_request_size: int = Field(
        default=10485760, env="MAX_REQUEST_SIZE", ge=1024
    )  # 10MB default for file uploads
    
    @field_validator("cors_origins")
    def validate_cors_origins(cls, v):
        """Validate CORS origins"""
        if isinstance(v, str):
            # Handle comma-separated string
            return [origin.strip() for origin in v.split(",") if origin.strip()]
        return v


class ServerConfig(BaseSettings):
    """Server configuration settings"""
    
    # Server settings - optimized for HuggingFace Spaces
    host: str = Field(default="0.0.0.0", env="HOST")
    port: int = Field(default=7860, env="PORT", ge=1, le=65535)  # HF Spaces default
    workers: int = Field(default=1, env="WORKERS", ge=1, le=4)
    reload: bool = Field(default=False, env="RELOAD")
    debug: bool = Field(default=False, env="DEBUG")
    
    @field_validator("reload", "debug", mode='before')
    @classmethod
    def validate_server_boolean_fields(cls, v):
        """Convert string boolean values to actual booleans"""
        if isinstance(v, str):
            v = v.strip().lower()
            if v in ('true', '1', 'yes', 'on'):
                return True
            elif v in ('false', '0', 'no', 'off', ''):
                return False
            else:
                raise ValueError(f"Invalid boolean value: {v}")
        return v
    
    # Request handling
    request_timeout: int = Field(default=30, env="REQUEST_TIMEOUT", ge=1, le=300)
    max_trees_per_request: int = Field(
        default=3000, env="MAX_TREES_PER_REQUEST", ge=1, le=10000
    )


class SupabaseConfig(BaseSettings):
    """Supabase configuration settings"""
    
    # Supabase credentials - optional for development
    supabase_url: Optional[str] = Field(default=None, env="SUPABASE_URL")
    supabase_anon_key: Optional[str] = Field(default=None, env="SUPABASE_ANON_KEY") 
    supabase_service_role_key: Optional[str] = Field(default=None, env="SUPABASE_SERVICE_ROLE_KEY")
    
    # Storage bucket names
    image_bucket: str = Field(default="tree-images", env="IMAGE_BUCKET")
    audio_bucket: str = Field(default="tree-audios", env="AUDIO_BUCKET")
    
    # File URL expiry (in seconds)
    signed_url_expiry: int = Field(default=3600, env="SIGNED_URL_EXPIRY", ge=300)
    
    @field_validator("supabase_url")
    def validate_supabase_url(cls, v):
        """Validate Supabase URL format"""
        if v is not None and not v.startswith("https://"):
            raise ValueError("SUPABASE_URL must be a valid HTTPS URL")
        return v
    
    # Remove key validation - accept any provided keys for deployment flexibility


class ApplicationConfig(BaseSettings):
    """Main application configuration"""
    
    # Application metadata
    app_name: str = Field(default="TreeTrack", env="APP_NAME")
    app_version: str = Field(default="3.0.0", env="APP_VERSION")
    app_description: str = Field(
        default="Tree mapping and tracking with cloud storage", 
        env="APP_DESCRIPTION"
    )
    environment: str = Field(default="production", env="ENVIRONMENT")
    
    # Conference/Demo mode
    conference_mode: bool = Field(default=False, env="CONFERENCE_MODE")
    demo_mode: bool = Field(default=False, env="DEMO_MODE")
    
    @field_validator("conference_mode", "demo_mode", mode='before')
    @classmethod
    def validate_boolean_fields(cls, v):
        """Convert string boolean values to actual booleans"""
        if isinstance(v, str):
            v = v.strip().lower()
            if v in ('true', '1', 'yes', 'on'):
                return True
            elif v in ('false', '0', 'no', 'off', ''):
                return False
            else:
                raise ValueError(f"Invalid boolean value: {v}")
        return v
    
    # Feature flags
    enable_api_docs: bool = Field(default=True, env="ENABLE_API_DOCS")
    enable_frontend: bool = Field(default=True, env="ENABLE_FRONTEND") 
    enable_statistics: bool = Field(default=True, env="ENABLE_STATISTICS")
    enable_master_db: bool = Field(default=True, env="ENABLE_MASTER_DB")
    
    @field_validator("enable_api_docs", "enable_frontend", "enable_statistics", "enable_master_db", mode='before')
    @classmethod
    def validate_feature_flags(cls, v):
        """Convert string boolean values to actual booleans"""
        if isinstance(v, str):
            v = v.strip().lower()
            if v in ('true', '1', 'yes', 'on'):
                return True
            elif v in ('false', '0', 'no', 'off', ''):
                return False
            else:
                raise ValueError(f"Invalid boolean value: {v}")
        return v
    
    # Data validation limits
    max_species_length: int = Field(default=200, env="MAX_SPECIES_LENGTH", ge=1, le=500)
    max_notes_length: int = Field(default=2000, env="MAX_NOTES_LENGTH", ge=1, le=10000)
    
    @field_validator("environment")
    def validate_environment(cls, v):
        """Validate environment"""
        valid_envs = ["development", "testing", "staging", "production"]
        if v.lower() not in valid_envs:
            raise ValueError(f"Environment must be one of: {valid_envs}")
        return v.lower()


class Settings(BaseSettings):
    """Combined application settings"""
    
    # Sub-configurations
    security: SecurityConfig = SecurityConfig()
    server: ServerConfig = ServerConfig()
    supabase: SupabaseConfig = SupabaseConfig()
    app: ApplicationConfig = ApplicationConfig()
    
    def is_development(self) -> bool:
        """Check if running in development mode"""
        return self.app.environment == "development"
    
    def is_production(self) -> bool:
        """Check if running in production mode"""
        return self.app.environment == "production"
    
    def is_conference_mode(self) -> bool:
        """Check if running in conference demo mode"""
        return self.app.conference_mode
    
    def is_demo_mode(self) -> bool:
        """Check if running in demo mode (no database writes)"""
        return self.app.demo_mode or self.app.conference_mode
    
    def get_cors_config(self) -> dict:
        """Get CORS configuration"""
        return {
            "allow_origins": self.security.cors_origins,
            "allow_credentials": True,
            "allow_methods": ["GET", "POST", "PUT", "DELETE", "OPTIONS"],
            "allow_headers": ["*"],
        }
    
    class Config:
        env_file = ".env"
        env_file_encoding = "utf-8"
        case_sensitive = False
        extra = "allow"  # Allow extra fields during development


@lru_cache
def get_settings() -> Settings:
    """Get cached application settings"""
    return Settings()


# For backward compatibility - expose individual configs
def get_security_config():
    return get_settings().security

def get_server_config():
    return get_settings().server

def get_supabase_config():
    return get_settings().supabase


if __name__ == "__main__":
    # Test configuration loading
    try:
        settings = get_settings()
        print("Configuration loaded successfully")
        print(f"App: {settings.app.app_name} v{settings.app.app_version}")
        print(f"Environment: {settings.app.environment}")
        print(f"Server: {settings.server.host}:{settings.server.port}")
        print(f"Supabase URL: {settings.supabase.supabase_url}")
        print(f"CORS Origins: {settings.security.cors_origins}")
        
    except Exception as e:
        print(f"Configuration error: {e}")
        exit(1)