/*
* Global variables for the script
*/
const isWidget = config.runsInWidget

const dayColors = [
  new Color("#ff7b1c"),
  new Color("#ce6a23")
]

const nightColors = [
  new Color("#1b2556"),
  new Color("#1e2c72")
]

const locationFileName = "location.json"

const parseDateFormatter = new DateFormatter()
parseDateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"

const uiDateFormatter = new DateFormatter()
uiDateFormatter.dateFormat = "HH:mm"

const fileManager = FileManager.local()

/*
 * Methods
 */

const getFilePath = (fileName) => {
  const docsPath = fileManager.documentsDirectory()
  const path = fileManager.joinPath(docsPath, fileName)

  return path
}

const saveToFile = (content, fileName) => {
  fileManager.writeString(getFilePath(fileName), content)
}

const readFromFile = (fileName) => {
  return fileManager.readString(getFilePath(fileName))
}

const fetchTimes = async (location) => {

  const { latitude, longitude } = location

  // fetch sunrise/sunset times
  const sunriseApiUrl = "https://api.sunrise-sunset.org/json?lat=" + latitude + "&lng=" + longitude + "&formatted=0"

  const timesRequest = new Request(sunriseApiUrl)
  const timesJsonResponse = (await timesRequest.loadJSON())

  const timesJson = timesJsonResponse.results

  const sunriseDateRaw = timesJson.sunrise
  const sunsetDateRaw = timesJson.sunset

  const sunriseDate = parseDateFormatter.date(sunriseDateRaw)
  const sunsetDate = parseDateFormatter.date(sunsetDateRaw)

  return {
    sunriseDate, sunsetDate
  }
}

const buildWidget = (
  sunriseDateFormatted,
  sunsetDateFormatted,
  bgColors
) => {
  const list = new ListWidget()
  const background = new LinearGradient()
  background.colors = bgColors
  background.locations = [0.0, 1.0]
  list.backgroundGradient = background

  const timesFont = Font.systemFont(15)

  const sunriseTitle = list.addText("Sunrise")
  sunriseTitle.font = Font.title2()

  const sunriseDateText = list.addText(sunriseDateFormatted)
  sunriseDateText.font = timesFont

  list.addSpacer(16)

  const sunsetTitle = list.addText("Sunset")
  sunsetTitle.font = Font.title2()

  const sunsetText = list.addText(sunsetDateFormatted)
  sunsetText.font = timesFont

  return list
}

const fetchLocationForeground = async () => {
  // fetch approximate location
  Location.setAccuracyToThreeKilometers()
  const location = Location.current()
  const fetchedLocation = await location
  const latitude = fetchedLocation.latitude
  const longitude = fetchedLocation.longitude

  return {
    latitude, longitude
  }
}

const fetchLocation = async () => {
  if (isWidget) {
    const cachedLocationRaw = readFromFile(locationFileName)

    return JSON.parse(cachedLocationRaw)
  } else {
    return await fetchLocationForeground()
  }
}

const isDayMode = (sunriseDate, sunsetDate) => {
  const date = new Date()

  return date >= sunriseDate || date <= sunsetDate
}

// Main body
const location = await fetchLocation()

const {
  sunriseDate, sunsetDate
} = await fetchTimes(location)

const sunsetDateFormatted = uiDateFormatter.string(sunsetDate)
const sunriseDateFormatted = uiDateFormatter.string(sunriseDate)

const list = buildWidget(
sunriseDateFormatted,
sunsetDateFormatted,
isDayMode(sunriseDate, sunsetDate) ? dayColors : nightColors
)

if (!isWidget) {
  saveToFile(JSON.stringify(location), locationFileName)

  const alert = new Alert()
  alert.title = "Updated current location successfully"

  alert.addAction("OK")
  alert.addAction("See widget preview (small)")
  alert.addAction("See widget preview (medium)")
  alert.addAction("See widget preview (large)")

  const selection = await alert.present()

  switch (selection) {
    case 1:
      await list.presentSmall()
      break
    case 2:
      await list.presentMedium()
      break
    case 3:
      await list.presentLarge()
      break
  }


  Script.complete()
  return
}

Script.setWidget(list)
Script.complete()