from datetime import datetime
from typing import Literal

from pydantic import BaseModel, ConfigDict, Field

class ScadaDeviceResponse(BaseModel):
    """Project SCADA metadata keyed by the canonical device identifier."""

    device_id: str
    device_type: str
    node_id: str | None = None
    link_id: str | None = None
    api_query_id: str | None = None
    measurement_unit: str
    transmission_mode: str
    transmission_frequency: str
    reliability: int | None = None
    x: float | None = None
    y: float | None = None
    longitude: float | None = None
    latitude: float | None = None


class ScadaLatestReadingResponse(BaseModel):
    """Latest persisted observation for one project SCADA device."""

    model_config = ConfigDict(extra="forbid", allow_inf_nan=False)

    device_id: str
    device_type: str
    measurement_unit: str
    transmission_mode: str
    transmission_frequency: str
    observed_at: datetime | None = None
    monitored_value: float | None = None
    cleaned_value: float | None = None


class ScadaLatestReadingsResponse(BaseModel):
    """Bounded device page with each device's latest persisted observation."""

    model_config = ConfigDict(extra="forbid", allow_inf_nan=False)

    items: list[ScadaLatestReadingResponse]
    total: int = Field(ge=0)
    limit: int = Field(ge=1, le=500)
    offset: int = Field(ge=0)
    observed_count: int = Field(ge=0)
    latest_observed_at: datetime | None = None


class ScadaRawReading(BaseModel):
    model_config = ConfigDict(extra="forbid", allow_inf_nan=False)

    time: datetime
    device_id: str
    monitored_value: float | None
    quality: Literal["unvalidated", "missing", "invalid"] = "unvalidated"


class ScadaRawPage(BaseModel):
    model_config = ConfigDict(extra="forbid", allow_inf_nan=False)

    items: list[ScadaRawReading]
    next_cursor: str | None
    scanned_through: datetime