from pydantic import BaseModel, Field, field_validator
from typing import Optional, List
from datetime import datetime
from decimal import Decimal


class UserBase(BaseModel):
    email: str = Field(..., max_length=255)
    name: str = Field(..., min_length=1, max_length=200)
    department_id: Optional[str] = None
    role_id: Optional[str] = None
    skills: Optional[List[str]] = None
    capacity: Optional[Decimal] = Field(Decimal("40.00"), ge=0, le=168)


class UserCreate(UserBase):
    pass


class UserUpdate(BaseModel):
    name: Optional[str] = Field(None, min_length=1, max_length=200)
    department_id: Optional[str] = None
    role_id: Optional[str] = None
    skills: Optional[List[str]] = None
    capacity: Optional[Decimal] = Field(None, ge=0, le=168)
    is_active: Optional[bool] = None


class UserResponse(UserBase):
    id: str
    is_active: bool
    is_system_admin: bool
    created_at: datetime
    updated_at: datetime

    class Config:
        from_attributes = True


class UserInDB(UserResponse):
    pass


class CapacityUpdate(BaseModel):
    """Schema for updating user's weekly capacity hours."""
    capacity_hours: Decimal

    @field_validator("capacity_hours")
    @classmethod
    def validate_capacity_hours(cls, v: Decimal) -> Decimal:
        """Validate capacity hours is within valid range (0-168)."""
        if v < 0:
            raise ValueError("Capacity hours must be non-negative")
        if v > 168:
            raise ValueError("Capacity hours cannot exceed 168 (hours in a week)")
        return v

    class Config:
        json_schema_extra = {
            "example": {
                "capacity_hours": 40.00
            }
        }