# @name    YouTube
# @desc    Subscriber count of a YouTube channel
# @author  Blueforcer
# @version 2.0
# @config  chan  text   "Channel ID" default="UCpGLALzRO0uaasWTsm9M99w" maxlen=32 help="The UC... part of youtube.com/channel/UC..., not the @handle"

class YouTube
  var url, chan, period
  var subs, label, full, err
  var ticks, busy
  var ramp

  def init()
    self.chan = store.get("chan")
    self.url = "https://api.socialcounts.org/youtube-live-subscriber-count/" +
               self.chan
    self.period = 3600            # once an hour

    self.subs = store.get("who") == self.chan ? store.get("n") : nil
    self.label = self.subs == nil ? nil : self.human(self.subs)
    self.full = self.subs == nil ? nil : str(self.subs)
    self.err = false
    self.ticks = 21
    self.busy = false
    self.ramp = [0xFF0000, 0xFF6666]
  end


  def human(n)
    if n < 1000 return str(n) end
    var d = 1000
    var suf = "K"
    if n >= 1000000000
      d = 1000000000
      suf = "B"
    elif n >= 1000000
      d = 1000000
      suf = "M"
    end
    var v = n / (d + 0.0)
    if v >= 10 return str(round(v)) + suf end
    var t = round(v * 10)
    return str(int(t / 10)) + "." + str(t % 10) + suf
  end

  def on_body(body, status)
    self.busy = false
    shared.set("f", 0)
    if status != 200 || body == nil
      self.err = true
      return
    end

    var m = re.search("(\\d+)", body)
    if m == nil
      self.err = true
      return
    end

    var n = num(m[1])
    if n == nil return end
    self.err = false
    if n == self.subs return end

    self.subs = n
    self.full = str(n)
    self.label = self.human(n)       # built here, not per frame
    store.set("n", n)
    store.set("who", self.chan)
  end


  def tls_busy()
    for k : shared.keys()
      if size(k) > 2 && k[size(k) - 2 .. size(k) - 1] == ".f" && shared.get(k) == 1
        var a = shared.age(k)
        if a != nil && a < 20000 return true end
      end
    end
    return false
  end

  def loop()
    if self.ticks <= 0
      if !self.busy && !self.tls_busy()
        self.ticks = self.period
        self.busy = true
        shared.set("f", 1)
        # The first hit in the body is the live estimate.
        http.get(self.url, / b, st -> self.on_body(b, st),
                 {'find': "\"subscriberCount\":", 'keep': 32})
      end
    end
    self.ticks -= 1
  end

  def draw()
    clear()
    rect_fill(0, 1, 8, 6, 0xFF0000)
    line(1, 0, 6, 0, 0xFF0000)
    line(1, 7, 6, 7, 0xFF0000)
    line(3, 2, 3, 6, 0xFFFFFF)
    line(4, 3, 4, 5, 0xFFFFFF)
    pixel(5, 4, 0xFFFFFF)

    if self.label != nil
      var avail = width() - 9
      var s = self.full
      var w = text_ink_width(s)
      if w > avail
        s = self.label
        w = text_ink_width(s)
      end
      ramp_text(9 + (avail - w) / 2, 6, s, self.ramp)
      return
    end

    var s = self.err ? "?" : "..."
    var w = text_ink_width(s)
    text(9 + (width() - 9 - w) / 2, 6, s, self.err ? 0xCC7722 : 0x555555)
  end

end

return YouTube()