import os
from typing import List, Optional, Union
try:
    from pydantic_settings import BaseSettings, SettingsConfigDict
except ImportError:
    from pydantic import BaseModel
    class BaseSettings(BaseModel):  # type: ignore
        def __init__(self, **kwargs):
            env_kwargs = {}
            for field_name, field_info in self.model_fields.items():
                alias = getattr(field_info, 'alias', None)
                keys_to_check = [k for k in [alias, field_name.upper(), field_name] if k]
                for k in keys_to_check:
                    if k in os.environ:
                        env_kwargs[field_name] = os.environ[k]
                        break
            env_kwargs.update(kwargs)
            super().__init__(**env_kwargs)
    SettingsConfigDict = dict  # type: ignore
from pydantic import Field, field_validator


class Settings(BaseSettings):
    # Environment
    app_env: str = Field(default="production", alias="APP_ENV")
    app_name: str = "CropAI Cloud Inference Backend"
    app_version: str = "1.2.0"
    debug: bool = Field(default=False, alias="DEBUG")

    # Server Network
    host: str = Field(default="0.0.0.0", alias="HOST")
    port: int = Field(default=8000, alias="PORT")
    allowed_origins: Union[List[str], str] = Field(
        default=["*"],
        alias="ALLOWED_ORIGINS"
    )

    # Google Gemini Multimodal Vision API Key (Confidential Server-Side)
    gemini_api_key: Optional[str] = Field(default=None, alias="GEMINI_API_KEY")
    gemini_model_name: str = Field(default="gemini-3.8-flash", alias="GEMINI_MODEL_NAME")

    # ML Inference Settings
    primary_hf_model: str = Field(
        default="linkanjarad/mobilenet_v2_1.0_224-plant-disease-identification",
        alias="PRIMARY_HF_MODEL"
    )
    rice_hf_model: str = Field(
        default="prithivMLmods/Rice-Leaf-Disease",
        alias="RICE_HF_MODEL"
    )
    enable_warmup: bool = True
    max_image_size_mb: int = Field(default=15, alias="MAX_IMAGE_SIZE_MB")
    confidence_threshold_warning: float = 0.70

    # Rate Limiting & Security
    rate_limit_per_minute: int = Field(default=120, alias="RATE_LIMIT_PER_MINUTE")
    secret_key: str = Field(default="cropai-secret-key-prod-2026", alias="SECRET_KEY")

    # Agronomic Hotlines
    kisan_helpline: str = "+918817814859"
    expert_whatsapp: str = "+918817814859"

    # Cloud Persistence (Google Cloud Firestore / GCP)
    gcp_project_id: Optional[str] = Field(default=None, alias="GCP_PROJECT_ID")
    firestore_collection_tickets: str = "cropai_expert_tickets"
    firestore_collection_diagnoses: str = "cropai_diagnoses"

    @property
    def cors_origins(self) -> List[str]:
        if isinstance(self.allowed_origins, str):
            return [o.strip() for o in self.allowed_origins.split(",") if o.strip()]
        return self.allowed_origins

    model_config = SettingsConfigDict(
        env_file=os.path.join(os.path.dirname(__file__), ".env"),
        env_file_encoding="utf-8",
        extra="ignore"
    )


settings = Settings()