"""Pydantic schemas for file attachments"""

from datetime import datetime
from typing import Optional

from pydantic import (BaseModel, ConfigDict, Field, field_serializer,
                      field_validator)


class FileUploadRequest(BaseModel):
    """Schema for file upload request"""

    entity_type: str = Field(..., description="Type of entity (Card, Comment, etc.)")
    entity_id: int = Field(..., description="ID of entity")

    @field_validator("entity_type")
    @classmethod
    def validate_entity_type(cls, v: str) -> str:
        """Validate entity type is allowed"""
        valid_types = ["Card", "Comment", "Epic", "Board"]
        if v not in valid_types:
            raise ValueError(f"Invalid entity_type: {v}. Must be one of {valid_types}")
        return v

    model_config = ConfigDict(from_attributes=True)


class FileAttachmentWithUrlResponse(BaseModel):
    """
    Schema for file attachment with secure URLs

    Security: Only exposes public-facing information.
    Internal details (MinIO paths, IDs, etc.) are hidden.
    """

    uuid: str
    original_name: str
    file_type: str
    file_size: int
    created_at: datetime
    download_url: str
    thumbnail_url: Optional[str] = None
    view_url: str
    mime_type: str

    @field_serializer("created_at")
    def serialize_created_at(self, value: datetime) -> str:
        """Serialize datetime to ISO format string"""
        return value.isoformat() if value else None

    model_config = ConfigDict(from_attributes=True)


class FileDeleteResponse(BaseModel):
    """Schema for file delete response"""

    message: str = Field(..., description="Deletion status message")
    file_id: int = Field(..., description="ID of deleted file")


class MultipleFilesResponse(BaseModel):
    """Schema for multiple files response"""

    files: list[FileAttachmentWithUrlResponse]
    count: int = Field(..., description="Number of files")


class ValidationError(BaseModel):
    """Schema for validation errors"""

    error: str = Field(..., description="Error message")
    details: Optional[dict] = None