bk/src/bk.nim

import htmlparser, json, net, options, os, strscans, times, unicode, uri, xmltree
from strutils import ffDecimal, formatFloat, replace
import cligen, colorize, elvis
from bakalari as baka import Grade, newBakalari

type
  Config = object
    website: string
    username: string
    refreshToken: string

const
  defaultConfigFile = getConfigDir() / "bk.json"
  dayNames = [
    1: "Mon",
    2: "Tue",
    3: "Wed",
    4: "Thu",
    5: "Fri",
    6: "Sat",
    7: "Sun",
  ]

proc error(message: string) {.noReturn.} =
  stderr.writeLine("Error: " & message)
  quit QuitFailure

proc loadConfig(configFile = defaultConfigFile): Config =
  try:
    configFile.readFile.parseJson.to(Config)
  except IOError:
    error "Can't read the config file. Are you signed in?"
  except JsonParsingError, JsonKindError:
    error "Invalid config file. Make sure it's in JSON format."
  except KeyError:
    error "The config file doesn't contain all necessary fields."

proc saveConfig(configFile = defaultConfigFile, config: Config) =
  try:
    configFile.writeFile((%*config).pretty)
  except IOError:
    error "Can't write the config file."

template withBakalari(configFile: string, body: untyped): untyped =
  var config = configFile.loadConfig
  let bakalari {.inject.} = newBakalari(config.website.parseUri, config.refreshToken)
  try:
    body
  finally:
    config.refreshToken = bakalari.refreshToken
    configFile.saveConfig(config)

proc signin(
  website: string,
  username: string,
  password: string,
  configFile = defaultConfigFile,
  ) =
  ## sign in to Bakaláři and save the credentials
  let
    bakalari = newBakalari(website.parseUri, username, password)
    config = Config(
      website: website,
      username: username,
      refreshToken: bakalari.refreshToken,
    )
  configFile.saveConfig(config)

proc average(grades: seq[Grade]): float =
  var sum, weightSum: float
  for grade in grades:
    var value: int
    if scanf(grade.text, "$i-", value):
      sum += (value.float + 0.5) * grade.weight.float
      weightSum += grade.weight.float
    elif scanf(grade.text, "$i", value):
      sum += value.float * grade.weight.float
      weightSum += grade.weight.float
  return weightSum ? (sum / weightSum) ! 0.0

proc grades(
  configFile = defaultConfigFile,
  ) =
  ## display the list of grades and calculate averages
  withBakalari(configFile):
    for subject in baka.grades(bakalari):
      stdout.writeLine subject.name.fgLightYellow & " " & subject.grades.average.formatFloat(ffDecimal, 2)
      for grade in subject.grades:
        var line = ""
        line &= grade.text.align(2).fgLightMagenta
        line &= " "
        line &= ($grade.weight).align(2).fgLightCyan
        line &= " "
        line &= grade.caption
        stdout.writeLine line

proc homework(
  configFile = defaultConfigFile,
  ) =
  ## display the list of homework
  withBakalari(configFile):
    for homework in baka.homework(bakalari):
      stdout.writeLine "----------------------------------------------------------------".fgLightGray
      stdout.writeLine (homework.startTime.format("yyyy-MM-dd") & " / " & homework.endTime.format("yyyy-MM-dd")).fgLightCyan
      stdout.writeLine homework.subject.fgLightYellow
      stdout.writeLine homework.teacher.fgLightMagenta
      stdout.writeLine homework.content

proc messages(
  configFile = defaultConfigFile,
  ) =
  withBakalari(defaultConfigFile):
    for message in baka.messages(bakalari):
      stdout.writeLine "----------------------------------------------------------------".fgLightGray
      stdout.writeLine message.sentTime.format("yyyy-MM-dd") .fgLightCyan
      stdout.writeLine message.title.fgLightYellow
      stdout.writeLine message.sender.fgLightMagenta
      stdout.writeLine message.text.replace("<br />", "{{br}}").parseHtml.innerText.replace("{{br}}", "\n")

proc timetable(
  configFile = defaultConfigFile,
  date = "",
  nextWeek = false,
  oneDay = false,
  permanent = false,
  ) =
  ## display the timetable (for the current week by default)
  let date = if ?date:
    try:
      date.parse("yyyyMMdd")
    except TimeParseError:
      error "Can't parse the date. Make sure it's in YYYYMMDD format."
  else:
    nextWeek ? (now() + 1.weeks) ! now()
  withBakalari(configFile):
    let timetable = baka.timetable(bakalari, permanent, some(date))
    for day in timetable.days:
      if oneDay:
        if date.format("yyyyMMdd") != day.date.format("yyyyMMdd"):
          continue
      stdout.writeLine dayNames[day.dayOfWeek] & " " & day.date.format("yyyy-MM-dd")
      for lesson in day.lessons:
        var line = ""
        line &= lesson.hour.number
        line &= ". "
        line &= lesson.hour.beginTime.align(5, '0'.Rune).fgLightCyan
        line &= "-".fgLightCyan
        line &= lesson.hour.endTime.align(5, '0'.Rune).fgLightCyan
        line &= " "
        line &= lesson.subject.abbrev.align(4).fgLightYellow
        line &= " "
        line &= lesson.teacher.abbrev.align(4).fgLightMagenta
        line &= " "
        line &= lesson.room.abbrev.align(4).fgLightGreen
        stdout.writeLine line
        if lesson.change.isSome:
          stdout.writeLine ("^ " & lesson.change.unsafeGet.fgLightRed).fgLightRed

try:
  dispatchMulti(
    [signin, help = {
      "website": "the URL for Bakaláři (e.g. https://bakalari.myschool.cz)",
      "username": "your username",
      "password": "your password (will not be stored anywhere)",
      "config-file": "where to store the credentials",
    }],
    [grades, help = {
      "config-file": "where the credentials are stored",
    }],
    [homework, help = {
      "config-file": "where the credentials are stored",
    }],
    [messages, help = {
      "config-file": "where the credentials are stored",
    }],
    [timetable, help = {
      "config-file": "where the credentials are stored",
      "date": "any date inside the week you want to display, in YYYYMMDD format (defaults to today)",
      "nextWeek": "display the next week rather that the current week (overriden by --date)",
      "one-day": "display only the specified day",
      "permanent": "display the permanent timetable",
    }],
    )
except OSError:
  error "Generic OS error. Check your internet connection."
except SslError:
  error "Connection interrupted. Check your internet connection."