from datetime import datetime
from typing import Literal, Optional
from uuid import UUID
from pydantic import BaseModel, EmailStr, Field, model_validator


class InviteCodeCreate(BaseModel):
    """Schema for creating a new invite code."""
    expires_at: Optional[datetime] = Field(None, description="Optional expiration time")
    note: Optional[str] = Field(None, max_length=255, description="Note about who this code is for")
    email: Optional[EmailStr] = Field(None, description="Recipient email for invite delivery")
    assigned_plan: Literal["free", "pro", "starter", "enterprise"] = Field("free", description="Plan to assign on registration")
    trial_duration_days: Optional[int] = Field(None, ge=1, le=90, description="Trial duration in days (1-90)")

    @model_validator(mode="after")
    def free_plan_no_trial(self):
        if self.assigned_plan == "free" and self.trial_duration_days is not None:
            raise ValueError("Free plan cannot have a trial duration")
        return self


class InviteCodeResponse(BaseModel):
    """Schema for invite code response."""
    id: UUID
    code: str
    created_by_id: UUID
    used_by_id: Optional[UUID] = None
    expires_at: Optional[datetime] = None
    note: Optional[str] = None
    created_at: datetime
    used_at: Optional[datetime] = None
    is_used: bool
    is_expired: bool
    is_valid: bool
    email: Optional[str] = None
    assigned_plan: str = "free"
    trial_duration_days: Optional[int] = None
    email_sent_at: Optional[datetime] = None
    has_trial: bool = False
    email_sent: bool = False

    class Config:
        from_attributes = True


class InviteCodeValidation(BaseModel):
    """Schema for invite code validation response."""
    valid: bool
    message: str