from datetime import datetime, timezone
from enum import Enum
from typing import Annotated
from uuid import UUID

from pydantic import AnyHttpUrl, BaseModel, ConfigDict, Field, StringConstraints, field_validator

Name = Annotated[str, StringConstraints(strip_whitespace=True, min_length=1, max_length=100)]


def utcnow() -> datetime:
    return datetime.now(timezone.utc)


class MonitorStatus(str, Enum):
    unknown = "unknown"
    up = "up"
    down = "down"
    error = "error"


class MonitorCreate(BaseModel):
    name: Name
    url: AnyHttpUrl

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


class MonitorUpdate(MonitorCreate):
    pass


class Monitor(BaseModel):
    model_config = ConfigDict(frozen=True)
    id: UUID
    name: str
    url: AnyHttpUrl
    status: MonitorStatus = MonitorStatus.unknown
    created_at: datetime
    updated_at: datetime
    checked_at: datetime | None = None
    latency_ms: float | None = Field(default=None, ge=0)
    http_status: int | None = Field(default=None, ge=100, le=599)
    error: str | None = None


class CheckResult(BaseModel):
    status: MonitorStatus
    checked_at: datetime
    latency_ms: float = Field(ge=0)
    http_status: int | None = None
    error: str | None = None


class StatusResponse(CheckResult):
    id: UUID


class ProbeResponse(BaseModel):
    status: str