//! Clock module: subscribes to the clock service, renders the time in the
//! bar. Left-click toggles the seconds suffix — and pokes the running clock
//! service to switch which kind it publishes; right-click opens a popup.

use iced::widget::{container, mouse_area, text};
use iced::{Element, Task};

use common::{BarModule, ClockKind, ClockMsg, ClockPayload, Endpoint, ModuleEffect, Service, Wire};
use serde::Deserialize;
use toml::Table;

/// Big-text popup size (logical px).
const POPUP_W: u32 = 360;
const POPUP_H: u32 = 160;

/// Errors digesting the `module.clock` config table.
#[derive(Debug, thiserror::Error)]
pub enum ClockError {
    /// Config value was present but not a bool.
    #[error("module.clock.{0} must be a bool")]
    NotBool(&'static str),
}

pub struct Clock {
    value: String,
    show_seconds: bool,
}

#[derive(Deserialize, Default)]
struct ClockConfig {
    #[serde(default)]
    show_seconds: bool,
}

impl Clock {
    pub fn new(config: Option<Table>) -> Self {
        match config_clock(config) {
            Some(x) => Self {
                value: "--:--:--".to_string(),
                show_seconds: x.show_seconds,
            },
            None => Self::default(),
        }
    }

    /// Display string: HH:MM:SS, or HH:MM when seconds are hidden.
    fn shown(&self) -> String {
        if self.show_seconds {
            self.value.clone()
        } else {
            self.value
                .split(':') // [hh, mm, ss]
                .take(2)
                .collect::<Vec<_>>()
                .join(":")
        }
    }
}

impl Default for Clock {
    fn default() -> Self {
        Self {
            value: "--:--:--".to_string(),
            show_seconds: false,
        }
    }
}

fn config_clock(table: Option<Table>) -> Option<ClockConfig> {
    let clock = table?.get("clock")?.clone();
    clock.try_into().ok()
}

impl BarModule for Clock {
    fn id(&self) -> &'static str {
        "clock"
    }

    fn view(&self, window_id: Option<iced::window::Id>) -> Element<'_, Wire> {
        let me = Endpoint::module(self.id());
        match window_id {
            // Popup surface: current time in large text.
            Some(_) => container(text(&self.value).size(56)).padding(20).into(),
            // Bar surface: clickable time. Container carries the module id
            // so the popup can anchor to these bounds.
            None => container(
                mouse_area(text(self.shown()).size(16))
                    .on_press(Wire::module(me, self.id(), ClockMsg::ToggleSeconds))
                    .on_right_press(Wire::module(me, self.id(), ClockMsg::OpenPopup)),
            )
            .id(iced::widget::Id::from(self.id()))
            .into(),
        }
    }

    fn update(&mut self, msg: Wire) -> Task<ModuleEffect> {
        // The service publishes a raw `ClockPayload`; UI sends `ClockMsg`.
        if let Some(payload) = msg.downcast::<ClockPayload>() {
            self.value = payload.value.clone();
            return Task::none();
        }
        match msg.downcast::<ClockMsg>() {
            Some(ClockMsg::ToggleSeconds) => {
                self.show_seconds = !self.show_seconds;
                tracing::debug!(show_seconds = self.show_seconds, "clock toggle");
                let want = if self.show_seconds {
                    ClockKind::Seconds
                } else {
                    ClockKind::Mins
                };
                // Poke the running clock service: tell it which kind to publish.
                Task::done(ModuleEffect::Send(Wire::service(
                    Endpoint::module(self.id()),
                    ClockKind::Seconds.key().0,
                    want,
                )))
            }
            Some(ClockMsg::OpenPopup) => Task::done(ModuleEffect::RequestPopup(
                self.id().to_string(),
                self.id().to_string(),
            )),
            None => Task::none(),
        }
    }

    fn services(&self) -> Vec<Service> {
        vec![ClockKind::Seconds.key()]
    }

    fn popup_size(&self) -> Option<(u32, u32)> {
        Some((POPUP_W, POPUP_H))
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    /// Regression: `new(None)` used to call `default()`, which called
    /// `new(None)` — infinite recursion (hard stack overflow) whenever the
    /// clock config was absent or failed to parse.
    #[test]
    fn no_config_terminates() {
        assert!(!Clock::new(None).show_seconds);
        assert!(!Clock::default().show_seconds);
    }
}