from datetime import datetime
from typing import Literal
from uuid import UUID

from pydantic import AnyHttpUrl, BaseModel, ConfigDict, Field, model_validator

StatusState = Literal["unknown", "up", "down", "error"]


class CheckStatus(BaseModel):
    state: StatusState = "unknown"
    checked_at: datetime | None = None
    status_code: int | None = None
    latency_ms: float | None = Field(default=None, ge=0)
    error: str | None = None


class MonitorCreate(BaseModel):
    name: str = Field(min_length=1, max_length=200)
    url: AnyHttpUrl


class MonitorUpdate(BaseModel):
    name: str | None = Field(default=None, min_length=1, max_length=200)
    url: AnyHttpUrl | None = None

    @model_validator(mode="after")
    def not_empty(self) -> "MonitorUpdate":
        if self.name is None and self.url is None:
            raise ValueError("at least one field is required")
        return self


class Monitor(BaseModel):
    model_config = ConfigDict(from_attributes=True)

    id: UUID
    name: str
    url: AnyHttpUrl
    created_at: datetime
    updated_at: datetime
    status: CheckStatus


class CheckResult(CheckStatus):
    monitor_id: UUID
    status_applied: bool = True


class HealthResponse(BaseModel):
    status: Literal["ok", "ready"]