use std::sync::Arc;

use chrono::{DateTime, Utc};
use iocraft::prelude::*;

use crate::{
    common::{ICONS, one_line, shown_title},
    store::{Task, ThingsStore},
    ui::components::{deadline_badge::DeadlineBadge, tags_badge::TagsBadge},
};

#[derive(Default, Props)]
pub struct TaskLineProps<'a> {
    pub task: Option<&'a Task>,
    pub show_today_markers: bool,
    pub show_staged_today_marker: bool,
    pub show_tags: bool,
    pub show_project: bool,
    pub show_area: bool,
}

#[component]
pub fn TaskLine<'a>(hooks: Hooks, props: &TaskLineProps<'a>) -> impl Into<AnyElement<'a>> {
    let Some(task) = props.task else {
        return element!(Fragment).into_any();
    };

    let store = hooks.use_context::<Arc<ThingsStore>>().clone();
    let today = *hooks.use_context::<DateTime<Utc>>();

    let leading = vec![
        marker_element(
            &store,
            task,
            &today,
            props.show_today_markers,
            props.show_staged_today_marker,
        ),
        title_element(task),
    ];

    let tags = if props.show_tags {
        element! { TagsBadge(tags: task.tags.clone()) }.into_any()
    } else {
        element!(Fragment).into_any()
    };

    let context = vec![
        reminder_element(task),
        tags,
        context_element(task, store.as_ref(), props.show_project, props.show_area),
        element! { DeadlineBadge(deadline: task.deadline) }.into_any(),
    ];

    element! {
        View(flex_direction: FlexDirection::Row, gap: 2) {
            View(flex_direction: FlexDirection::Row, gap: 1) { #(leading) }
            View(flex_direction: FlexDirection::Row, gap: 1) { #(context) }
        }
    }
    .into_any()
}

/// the markers of a to-do that Today lists
///
/// a to-do in the Trash or in a closed project or heading carries none
fn marker_element<'a>(
    store: &ThingsStore,
    task: &Task,
    today: &DateTime<Utc>,
    show_today_markers: bool,
    show_staged_today_marker: bool,
) -> AnyElement<'a> {
    if !store.in_today(task, today) {
        return element!(Fragment).into_any();
    }
    if show_today_markers {
        if task.evening {
            return element! { Text(content: ICONS.evening, color: Color::Blue) }.into_any();
        }
        return element! { Text(content: ICONS.today, color: Color::Yellow) }.into_any();
    }

    if show_staged_today_marker && task.is_staged_for_today(today) {
        return element! { Text(content: ICONS.today_staged, color: Color::Yellow) }.into_any();
    }

    element!(Fragment).into_any()
}

fn reminder_element<'a>(task: &Task) -> AnyElement<'a> {
    let Some(time) = task.reminder() else {
        return element!(Fragment).into_any();
    };
    element!(Text(content: format!("@{time}"), color: Color::DarkGrey)).into_any()
}

fn title_element<'a>(task: &Task) -> AnyElement<'a> {
    if task.title.trim().is_empty() {
        return element!(Text(content: "(untitled)", color: Color::DarkGrey)).into_any();
    }

    let content = one_line(&task.title);
    element!(Text(content: content)).into_any()
}

fn context_element<'a>(
    task: &Task,
    store: &ThingsStore,
    show_project: bool,
    show_area: bool,
) -> AnyElement<'a> {
    if show_project && let Some(proj) = store.effective_project_uuid(task) {
        let title = store.resolve_project_title(&proj);
        return element! {
            Text(content: format!("[{} {}]", ICONS.project, one_line(&title)), color: Color::DarkGrey)
        }
        .into_any();
    }

    if show_area && let Some(area) = store.effective_area_uuid(task) {
        let title = store.resolve_area_title(&area);
        return element! {
            Text(content: format!("[{} {}]", ICONS.area, shown_title(&title)), color: Color::DarkGrey)
        }
        .into_any();
    }

    element!(Fragment).into_any()
}