import gleam/int
import gleam/json
import gleam/list
import gleam/option.{type Option, None, Some}
import gleam/result
import gleam/string
import lustre
import lustre/attribute.{class}
import lustre/effect.{type Effect}
import lustre/element.{type Element}
import lustre/element/html
import lustre/event
import plinth/browser/document
import plinth/browser/element as plinth_element
import shared.{type Room}

pub fn main() {
  let initial_items =
    document.query_selector("#model")
    |> result.map(plinth_element.inner_text)
    |> result.try(fn(json) {
      json.parse(json, shared.grocery_list_decoder())
      |> result.replace_error(Nil)
    })
    |> result.unwrap([])

  let app = lustre.application(init, update, view)
  let assert Ok(_) = lustre.start(app, "#app", initial_items)

  Nil
}

type Model {
  Model(
    rooms: List(Room),
    name: Option(String),
    pin: Option(String),
    typed: String,
  )
}

fn init(items: List(Room)) -> #(Model, Effect(State)) {
  let model = Model(rooms: items, name: None, pin: None, typed: "")

  #(model, effect.none())
}

type State {
  SelectRoom(String)
  Initial
  KeyIn(String)
}

fn update(model: Model, msg: State) -> #(Model, Effect(msg)) {
  case msg {
    Initial ->
      case model.name {
        _ -> #(model, effect.none())
      }
    SelectRoom(text) -> {
      #(Model(..model, name: Some(text)), effect.none())
    }
    KeyIn(newpin) -> {
      case string.length(newpin) < 4 {
        False -> #(Model(..model, pin: Some(newpin)), effect.none())
        True -> #(Model(..model, typed: newpin), effect.none())
      }
    }
  }
}

fn view(model: Model) -> Element(State) {
  case model.name, model.pin {
    None, _ ->
      html.div([], [
        html.div([class("terminal-header")], [
          html.div([class("terminal-status")], [
            html.span([class("status-blink")], [html.text("●")]),
            html.text(" SYSTEM READY"),
            html.span([class("ml-8")], [
              html.text("<< Please Log On to use QuizTerm. >>"),
            ]),
          ]),
        ]),
        view_room_list(model.rooms),
      ])
    Some(_), None -> {
      html.div([], [
        html.div([class("terminal-header")], [
          html.div([class("terminal-status")], [
            html.span([class("status-blink")], [html.text("●")]),
            html.text(" SYSTEM READY"),
            html.span([class("ml-8")], [
              html.text("<< Please Log On to use QuizTerm. >>"),
            ]),
          ]),
        ]),
        pin(),
      ])
    }
    Some(_), Some(_) -> {
      html.div([], [
        html.div([class("terminal-header")], [
          html.div([class("terminal-status")], [
            html.span([class("status-blink")], [html.text("●")]),
            html.text(" SYSTEM READY"),
            html.span([class("ml-8")], [
              html.text("<< Please Log On to use QuizTerm. >>"),
            ]),
          ]),
        ]),
        html.text("FETCHING USERS FOR ROOM"),
      ])
    }
  }
}

fn pin() -> Element(State) {
  html.div([attribute.class("terminal-section")], [
    html.div([attribute.class("terminal-label mb-4")], [
      html.text("Select room to play in"),
    ]),
    html.div([attribute.class("participants-grid")], [
      html.text("Enter PIN code for room"),
      html.input([
        attribute.type_("password"),
        event.on_input(KeyIn),
        attribute.autofocus(True),
      ]),
    ]),
  ])
}

fn view_room_list(items: List(Room)) -> Element(State) {
  html.div([attribute.class("terminal-section")], [
    html.div([attribute.class("terminal-label mb-4")], [
      html.text("Select room to play in"),
    ]),
    html.div([attribute.class("participants-grid")], case items {
      [] -> [html.text("No items in your list yet.")]
      _ -> {
        list.index_map(items, fn(item, index) {
          content_cell(index, item, SelectRoom)
        })
      }
    }),
  ])
}

fn content_cell(
  number: Int,
  room: Room,
  on_click: fn(String) -> msg,
) -> Element(msg) {
  html.div([class("participant-login"), event.on_click(on_click(room.name))], [
    html.div([class("participant-name")], [
      html.text("► " <> "[#" <> int.to_string(number) <> "] Team " <> room.name),
    ]),
  ])
}