//! barbar — a Wayland layer-shell status bar built on `iced` + `iced_layershell`.
//!
//! Renders a full-width bar pinned to the top of the screen via the
//! `wlr-layer-shell` protocol. Optionally target a specific output by
//! passing its name as the first CLI argument.

use iced::widget::{row, text};
use iced::{Alignment, Element, Length, Task, Theme};
use iced_layershell::application;
use iced_layershell::reexport::Anchor;
use iced_layershell::settings::{LayerShellSettings, StartMode, Settings};
use iced_layershell::to_layer_message;

/// Height of the bar in logical pixels.
const BAR_HEIGHT: u32 = 36;

/// Optional width of the bar; `None` means "as wide as the output".
const BAR_WIDTH: Option<u32> = None;

pub fn main() -> Result<(), iced_layershell::Error> {
    // Target a specific output if one was given, otherwise the active one.
    let start_mode = match std::env::args().nth(1) {
        Some(output) => StartMode::TargetScreen(output),
        None => StartMode::Active,
    };

    application(Bar::default, namespace, update, view)
        .style(style)
        .settings(Settings {
            layer_settings: LayerShellSettings {
                size: Some((BAR_WIDTH.unwrap_or(0), BAR_HEIGHT)),
                exclusive_zone: BAR_HEIGHT as i32,
                anchor: Anchor::Top | Anchor::Left | Anchor::Right,
                start_mode,
                ..Default::default()
            },
            ..Default::default()
        })
        .run()
}

/// Application state. Empty for now; placeholders will evolve into
/// workspace/clock/system modules.
#[derive(Debug, Default)]
struct Bar;

/// Messages produced by user input, events and subscriptions.
#[to_layer_message]
#[derive(Debug, Clone)]
enum Message {
    /// No-op used as a fallback target for pending subscriptions.
    Noop,
}

fn namespace() -> String {
    String::from("barbar")
}

fn update(_bar: &mut Bar, _message: Message) -> Task<Message> {
    Task::none()
}

fn view(_bar: &Bar) -> Element<'_, Message> {
    row![
        text("workspaces").size(14),
        text("|").size(14),
        text("clock").size(14),
        text("|").size(14),
        text("system").size(14),
    ]
    .spacing(12)
    .padding(8)
    .align_y(Alignment::Center)
    .width(Length::Fill)
    .height(Length::Fill)
    .into()
}

fn style(_bar: &Bar, theme: &Theme) -> iced::theme::Style {
    use iced::theme::Style;
    Style {
        background_color: theme.palette().background,
        text_color: theme.palette().text,
    }
}