#![windows_subsystem = "windows"]
use bevy::{prelude::*, winit::WinitSettings};
use bevy_egui::{
    egui::{self},
    EguiContexts, EguiPlugin,
};

#[cfg(windows)]
const LINE_ENDING: &str = "\r\n";
#[cfg(not(windows))]
const LINE_ENDING: &str = "\n";

#[derive(Resource, Debug)]
struct State {
    input_value: String,
    output_value: String,
    needs_update: bool,
}

fn main() {
    App::new()
        .insert_resource(WinitSettings::desktop_app())
        .insert_resource(State {
            input_value: "".to_string(),
            output_value: "".to_string(),
            needs_update: false,
        })
        .add_plugins(DefaultPlugins.set(WindowPlugin {
            primary_window: Some(Window {
                title: "dsort".to_string(),
                ..Default::default()
            }),
            ..Default::default()
        }))
        .add_plugins(EguiPlugin)
        .add_systems(Update, ui_system)
        .add_systems(Update, process_text)
        .run();
}

fn process_text(mut state: ResMut<State>) {
    if state.needs_update {
        let mut arr = state.input_value.lines().collect::<Vec<_>>();
        arr.retain(|&x| !x.is_empty());
        arr.sort_by(|&a, &b| vsort::compare(a, b));
        state.output_value = arr.join(LINE_ENDING);
        state.needs_update = false;
    }
}

fn ui_system(mut contexts: EguiContexts, mut state: ResMut<State>) {
    contexts.ctx_mut().set_visuals(egui::Visuals::light());

    egui::CentralPanel::default().show(contexts.ctx_mut(), |ui| {
        let window_size = ui.available_size();
        let height = window_size[1];

        ui.with_layout(egui::Layout::top_down(egui::Align::Center), |ui| {
            ui.with_layout(egui::Layout::left_to_right(egui::Align::LEFT), |ui| {
                let sort_button = ui.button("Sort & Remove Blanks");
                if sort_button.clicked() {
                    state.needs_update = true;
                }

                let copy_button = ui.button("Copy");
                if copy_button.clicked() {
                    ui.output_mut(|o| o.copied_text = state.output_value.clone());
                }

                let clear_button = ui.button("Clear");
                if clear_button.clicked() {
                    state.input_value = "".to_string();
                    state.needs_update = true;
                }
            });

            ui.with_layout(
                egui::Layout::left_to_right(egui::Align::Center).with_cross_justify(true),
                |ui| {
                    egui::ScrollArea::vertical()
                        .id_source("left")
                        .show(ui, |ui| {
                            ui.add_sized(
                                [ui.available_width() / 2., height],
                                egui::TextEdit::multiline(&mut state.input_value),
                            );
                        });

                    egui::ScrollArea::vertical()
                        .id_source("right")
                        .show(ui, |ui| {
                            ui.with_layout(
                                egui::Layout::top_down_justified(egui::Align::LEFT),
                                |ui| {
                                    ui.add(egui::Label::new(&state.output_value).selectable(true));
                                },
                            )
                        });
                },
            );
        });
    });
}