"""
Pydantic Configuration Models for OWILIX

This module provides type-safe configuration management using Pydantic.
Configurations can be loaded from YAML files or environment variables.
"""

from typing import Dict, List, Literal, Optional, Any
from pydantic import BaseModel, Field, field_validator
from pydantic_settings import BaseSettings
import os


class RepositoryConfig(BaseModel):
    """Configuration for a single repository.
    
    Attributes:
        repository: Type of repository backend.
        options: Backend-specific configuration options.
    """
    repository: Literal["lexis", "lexis+http", "s3a", "file"]
    options: Dict[str, Any] = Field(default_factory=dict)
    
    model_config = {"extra": "allow"}


class ProfileConfig(BaseModel):
    """Display profile configuration.
    
    Attributes:
        showfields: Comma-separated list of fields to display.
        nodisplay: Regex pattern for fields to hide.
        sort: Sort specification (e.g., "+startDate").
        colorder: Column ordering.
    """
    showfields: str = ""
    nodisplay: str = ".*"
    sort: str = "+startDate"
    colorder: str = ""
    
    model_config = {"extra": "allow"}


class ThemeConfig(BaseModel):
    """CLI theme colors."""
    info: str = "dim cyan"
    warning: str = "magenta"
    danger: str = "bold red"
    error: str = "bold red"
    
    model_config = {"extra": "allow"}


class UserConfig(BaseModel):
    """User metadata."""
    name: str = ""
    email: str = ""
    organisation: str = ""
    
    model_config = {"extra": "allow"}


class LoginConfig(BaseModel):
    """Authentication configuration."""
    username: Optional[str] = None
    password: Optional[str] = None
    
    model_config = {"extra": "allow"}


class GeneralConfig(BaseModel):
    """General settings."""
    version: str = ""
    server_update_url: str = Field(
        default="https://dashboard.ows.eu/api/owilix/default-cfg-0-17",
        alias="server-update-url"
    )
    license: Optional[str] = None
    
    model_config = {"extra": "allow", "populate_by_name": True}


class RepositoriesConfig(BaseModel):
    """Repositories configuration section."""
    config: Dict[str, RepositoryConfig] = Field(default_factory=dict)
    selected_remote: List[str] = Field(default_factory=list)
    selected_local: List[str] = Field(default_factory=list)
    
    model_config = {"extra": "allow"}


class OWILIXSettings(BaseModel):
    """
    Complete OWILIX configuration model.
    
    This model represents the full owilix.cfg YAML structure.
    
    Example YAML:
        general:
          version: "0.17.0"
          server-update-url: "https://..."
        repositories:
          config:
            it4i:
              repository: lexis+http
              options:
                zone: IT4ILexisV2
          selected_remote: [it4i]
          selected_local: [local]
        profiles:
          default:
            showfields: "..."
        theme:
          info: "dim cyan"
    """
    general: GeneralConfig = Field(default_factory=GeneralConfig)
    repositories: RepositoriesConfig = Field(default_factory=RepositoriesConfig)
    profiles: Dict[str, ProfileConfig] = Field(default_factory=dict)
    theme: ThemeConfig = Field(default_factory=ThemeConfig)
    user: UserConfig = Field(default_factory=UserConfig)
    dataset: Dict[str, Any] = Field(default_factory=dict)
    login: LoginConfig = Field(default_factory=LoginConfig)
    
    # Server-provided config (merged at runtime)
    server_config: Dict[str, Any] = Field(default_factory=dict, alias="server-config")
    
    model_config = {"extra": "allow", "populate_by_name": True}
    
    def get_repository(self, name: str) -> Optional[RepositoryConfig]:
        """Get a specific repository configuration."""
        return self.repositories.config.get(name)
    
    def get_remote_repositories(self) -> Dict[str, RepositoryConfig]:
        """Get all selected remote repositories."""
        return {
            k: v for k, v in self.repositories.config.items()
            if k in self.repositories.selected_remote
        }
    
    def get_local_repositories(self) -> Dict[str, RepositoryConfig]:
        """Get all selected local repositories."""
        return {
            k: v for k, v in self.repositories.config.items()
            if k in self.repositories.selected_local
        }
    
    def get_profile(self, name: str = "default") -> ProfileConfig:
        """Get a profile, merging with default."""
        default = self.profiles.get("default", ProfileConfig())
        if name == "default" or name not in self.profiles:
            return default
        # Merge specific profile over default
        profile_data = default.model_dump()
        profile_data.update(self.profiles[name].model_dump(exclude_unset=True))
        return ProfileConfig(**profile_data)


class OWILIXEnvSettings(BaseSettings):
    """
    Environment-based settings for OWILIX.
    
    These override or supplement file-based configuration.
    
    Environment Variables:
        OWILIX_LEXIS_PROJECT_NAME: Project name
        OWILIX_LEXIS_PROJECT_ID: Project ID
        OWS_OWI_PATH: Base path for OWILIX data
        OWILIX_IRODS_CONNECTION_TIMEOUT: iRODS timeout in seconds
        PY4LEXIS_TOKEN: Refresh token for authentication
    """
    project_name: str = Field(default="openwebsearch", alias="OWILIX_LEXIS_PROJECT_NAME")
    project_id: Optional[str] = Field(default=None, alias="OWILIX_LEXIS_PROJECT_ID")
    owi_path: str = Field(default="~/.owi", alias="OWS_OWI_PATH")
    irods_connection_timeout: int = Field(default=120, alias="OWILIX_IRODS_CONNECTION_TIMEOUT")
    py4lexis_token: Optional[str] = Field(default=None, alias="PY4LEXIS_TOKEN")
    
    model_config = {
        "env_prefix": "",  # Use explicit aliases
        "extra": "ignore",
        "populate_by_name": True,
    }
    
    @field_validator("owi_path")
    @classmethod
    def expand_path(cls, v: str) -> str:
        return os.path.expanduser(v)