from datetime import UTC, datetime
from enum import StrEnum
from uuid import UUID

from pydantic import BaseModel, ConfigDict, Field, field_validator
from pydantic.networks import AnyHttpUrl


class State(StrEnum):
    unknown = "unknown"
    up = "up"
    down = "down"
    error = "error"


class MonitorInput(BaseModel):
    name: str = Field(min_length=1, max_length=100)
    url: AnyHttpUrl
    timeout_seconds: float | None = Field(default=None, gt=0, le=30)

    @field_validator("url")
    @classmethod
    def reject_credentials(cls, value: AnyHttpUrl) -> AnyHttpUrl:
        if value.username or value.password:
            raise ValueError("URL credentials are not allowed")
        return value


class CheckSnapshot(BaseModel):
    state: State = State.unknown
    checked_at: datetime | None = None
    latency_ms: float | None = None
    http_status: int | None = None
    error: str | None = None


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

    id: UUID
    name: str
    url: AnyHttpUrl
    timeout_seconds: float | None
    created_at: datetime
    updated_at: datetime
    revision: int
    status: CheckSnapshot


class CheckResult(CheckSnapshot):
    monitor_id: UUID


def now() -> datetime:
    return datetime.now(UTC)