import type {
  HydroStation,
  RawHydroStation,
  RawSynopStation,
  RawWarning,
  SynopStation,
  WeatherMood,
  WeatherWarning,
  WarningKind,
} from "@/types/imgw";
import { translate, type Language } from "@/lib/i18n";
import { getProvinceFromTeryt, normalizeProvinceName } from "@/lib/provinces";
import type { CurrentWeatherCondition } from "@/types/imgw-current";

const locales: Record<Language, string> = { pl: "pl-PL", en: "en-GB" };

export function toNumber(value: unknown): number | null {
  if (typeof value === "number") return Number.isFinite(value) ? value : null;
  if (typeof value !== "string" || value.trim() === "") return null;
  const parsed = Number(value.replace(",", "."));
  return Number.isFinite(parsed) ? parsed : null;
}

function normalizeDate(value?: string | null): string | null {
  if (!value?.trim()) return null;
  const isoCandidate = value.includes("T") ? value : value.replace(" ", "T");
  const date = new Date(isoCandidate);
  return Number.isNaN(date.getTime()) ? null : date.toISOString();
}

function synopMeasuredAt(date?: string | null, hour?: string | null) {
  if (!date?.trim() || !hour?.trim()) return null;
  return normalizeDate(`${date}T${hour.padStart(2, "0")}:00:00Z`);
}

export function normalizeSynopStation(raw: RawSynopStation): SynopStation | null {
  if (!raw.id_stacji?.trim() || !raw.stacja?.trim()) return null;
  return {
    id: raw.id_stacji,
    name: raw.stacja,
    measuredAt: synopMeasuredAt(raw.data_pomiaru, raw.godzina_pomiaru),
    temperature: toNumber(raw.temperatura),
    windSpeed: toNumber(raw.predkosc_wiatru),
    windDirection: toNumber(raw.kierunek_wiatru),
    humidity: toNumber(raw.wilgotnosc_wzgledna),
    rainfall: toNumber(raw.suma_opadu),
    pressure: toNumber(raw.cisnienie),
  };
}

export function normalizeHydroStation(raw: RawHydroStation): HydroStation | null {
  if (!raw.id_stacji?.trim() || !raw.stacja?.trim()) return null;
  return {
    id: raw.id_stacji,
    name: raw.stacja,
    river: raw.rzeka?.trim() || null,
    province: raw.wojewodztwo?.trim() || null,
    longitude: toNumber(raw.lon),
    latitude: toNumber(raw.lat),
    waterLevel: toNumber(raw.stan_wody),
    waterLevelMeasuredAt: normalizeDate(raw.stan_wody_data_pomiaru),
    waterTemperature: toNumber(raw.temperatura_wody),
    waterTemperatureMeasuredAt: normalizeDate(raw.temperatura_wody_data_pomiaru),
    flow: toNumber(raw.przeplyw),
    flowMeasuredAt: normalizeDate(raw.przeplyw_data),
    icePhenomenon: toNumber(raw.zjawisko_lodowe),
    overgrowthPhenomenon: toNumber(raw.zjawisko_zarastania),
  };
}

export function normalizeWarning(raw: RawWarning, kind: WarningKind, index: number): WeatherWarning {
  const provinces = [...new Set([
    ...(raw.obszary ?? []).map((area) => normalizeProvinceName(area.wojewodztwo)),
    ...(raw.teryt ?? []).map(getProvinceFromTeryt),
  ].filter((province) => province !== null))];
  const describedAreas = (raw.obszary ?? [])
    .map((area) => area.opis?.trim() || area.wojewodztwo?.trim())
    .filter((area): area is string => Boolean(area));
  const areas = describedAreas.length ? describedAreas : provinces;
  const title = raw.zdarzenie?.trim() || raw.nazwa_zdarzenia?.trim() || "";
  return {
    id: `${kind}-${raw.id ?? raw.numer ?? index}-${raw.data_od ?? raw.obowiazuje_od ?? "unknown"}`,
    kind,
    level: toNumber(raw["stopień"] ?? raw.stopien),
    title,
    description: raw.przebieg?.trim() || raw.tresc?.trim() || null,
    comment: raw.komentarz?.trim() || null,
    validFrom: normalizeDate(raw.data_od ?? raw.obowiazuje_od),
    validTo: raw.data_do?.startsWith("9999-") ? null : normalizeDate(raw.data_do ?? raw.obowiazuje_do),
    publishedAt: normalizeDate(raw.opublikowano),
    probability: toNumber(raw.prawdopodobienstwo),
    areas,
    provinces,
    office: raw.biuro?.trim() || null,
  };
}

export function formatTemperature(value: number | null, language: Language = "pl") {
  return value === null ? translate(language, "common.noData") : `${Math.round(value)}°`;
}

export function formatPressure(value: number | null, language: Language = "pl") {
  return value === null ? translate(language, "common.noData") : `${value.toFixed(1)} hPa`;
}

export function formatHumidity(value: number | null, language: Language = "pl") {
  return value === null ? translate(language, "common.noData") : `${Math.round(value)}%`;
}

export function formatWind(speed: number | null, direction?: number | null, language: Language = "pl") {
  if (speed === null) return translate(language, "common.noData");
  const directionLabel = direction === null || direction === undefined ? "" : ` ${getWindDirection(direction)}`;
  return `${speed.toFixed(1)} m/s${directionLabel}`;
}

export function formatRainfall(value: number | null, language: Language = "pl") {
  return value === null ? translate(language, "common.noData") : `${value.toFixed(value < 1 ? 2 : 1)} mm`;
}

export function formatWaterLevel(value: number | null, language: Language = "pl") {
  return value === null ? translate(language, "common.noData") : `${Math.round(value)} cm`;
}

export function formatFlow(value: number | null, language: Language = "pl") {
  return value === null ? translate(language, "common.noData") : `${value.toFixed(2)} m³/s`;
}

export function formatDateTime(value: string | null, language: Language = "pl", fallback = translate(language, "common.noData")) {
  if (!value) return fallback;
  const date = new Date(value);
  if (Number.isNaN(date.getTime())) return fallback;
  return new Intl.DateTimeFormat(locales[language], {
    day: "numeric",
    month: "long",
    hour: "2-digit",
    minute: "2-digit",
  }).format(date);
}

export function calculateFeelsLike(temperature: number | null, humidity: number | null, windSpeed: number | null) {
  if (temperature === null) return null;
  if (temperature <= 10 && windSpeed !== null && windSpeed > 1.34) {
    const windKmh = windSpeed * 3.6;
    return 13.12 + 0.6215 * temperature - 11.37 * windKmh ** 0.16 + 0.3965 * temperature * windKmh ** 0.16;
  }
  if (temperature >= 27 && humidity !== null) {
    const c1 = -8.78469475556;
    const c2 = 1.61139411;
    const c3 = 2.33854883889;
    const c4 = -0.14611605;
    const c5 = -0.012308094;
    const c6 = -0.0164248277778;
    const c7 = 0.002211732;
    const c8 = 0.00072546;
    const c9 = -0.000003582;
    return c1 + c2 * temperature + c3 * humidity + c4 * temperature * humidity + c5 * temperature ** 2 +
      c6 * humidity ** 2 + c7 * temperature ** 2 * humidity + c8 * temperature * humidity ** 2 +
      c9 * temperature ** 2 * humidity ** 2;
  }
  return temperature;
}

export function getWindDirection(degrees: number) {
  const labels = ["N", "NE", "E", "SE", "S", "SW", "W", "NW"];
  return labels[Math.round((((degrees % 360) + 360) % 360) / 45) % 8];
}

export function getWeatherMoodFromData(station: SynopStation, date = new Date()): WeatherMood {
  const hour = date.getHours();
  if (hour < 6 || hour >= 21) return "night";
  if ((station.windSpeed ?? 0) >= 8) return "wind";
  if ((station.temperature ?? 15) <= 3) return "cold";
  if ((station.humidity ?? 0) >= 80) return "cloudy";
  if ((station.temperature ?? 15) >= 20) return "warm";
  return "mild";
}

export function getWeatherDescription(station: SynopStation, language: Language = "pl", condition?: CurrentWeatherCondition) {
  if (condition === "thunderstorm") return translate(language, "weather.thunderstorm");
  if (condition === "snow") return translate(language, "weather.currentSnow");
  if (condition === "rain") return translate(language, "weather.currentRain");
  if ((station.windSpeed ?? 0) >= 8) return translate(language, "weather.strongWind");
  if ((station.humidity ?? 0) >= 90) return translate(language, "weather.humid");
  return translate(language, "weather.calm");
}

export function moodGradient(mood: WeatherMood) {
  return {
    warm: "from-blue-500 via-blue-700 to-slate-900",
    cloudy: "from-slate-600 via-slate-700 to-slate-900",
    wind: "from-slate-500 via-blue-700 to-slate-900",
    cold: "from-blue-300 via-slate-500 to-slate-800",
    night: "from-slate-800 via-slate-900 to-slate-950",
    mild: "from-blue-500 via-slate-700 to-slate-900",
  }[mood];
}