guiedit 0.1.0

use std::{hash::Hasher, ops::DerefMut};

use crate::inspectable::Inspectable;

pub trait TreeNode: Inspectable {
    /// Searches for an object with the ID given in this element and its children, and calls its
    /// inspect_ui function if it is found.
    // TODO: Return controlflow for more performant search
    fn inspect_child(&mut self, this_id: u64, search_id: u64, ui: &mut egui::Ui);

    fn node_ui(&mut self, name: &str, id: u64, selected: &mut Option<u64>, ui: &mut egui::Ui) {
        default_parent_node_ui(
            std::any::type_name::<Self>(),
            name,
            id,
            selected,
            ui,
            |id, selected, ui| self.contents_ui(id, selected, ui),
        );
    }

    fn contents_ui(&mut self, _id: u64, _selected: &mut Option<u64>, _ui: &mut egui::Ui) {}
}

pub fn default_node_ui(
    type_name: &str,
    name: &str,
    id: u64,
    selected: &mut Option<u64>,
    ui: &mut egui::Ui,
) {
    ui.horizontal(|ui| {
        if ui
            .selectable_label(matches!(*selected, Some(i) if i == id), name)
            .clicked()
        {
            *selected = Some(id);
        }
        ui.add_enabled_ui(false, |ui| ui.small(type_name));
    });
}

pub fn default_parent_node_ui(
    type_name: &str,
    name: &str,
    id: u64,
    selected: &mut Option<u64>,
    ui: &mut egui::Ui,
    body: impl FnOnce(u64, &mut Option<u64>, &mut egui::Ui),
) {
    egui::collapsing_header::CollapsingState::load_with_default_open(
        ui.ctx(),
        ui.make_persistent_id(id),
        false,
    )
    .show_header(ui, |ui| {
        if ui
            .selectable_label(matches!(*selected, Some(i) if i == id), name)
            .clicked()
        {
            *selected = Some(id);
        }
        ui.add_enabled_ui(false, |ui| ui.small(type_name));
    })
    .body(|ui| body(id, selected, ui));
}

impl<T: TreeNode, const X: usize> TreeNode for [T; X] {
    fn inspect_child(&mut self, this_id: u64, search_id: u64, ui: &mut egui::Ui) {
        if this_id == search_id {
            self.inspect_ui(ui);
        } else {
            for (i, element) in self.into_iter().enumerate() {
                let mut hasher = std::collections::hash_map::DefaultHasher::default();
                hasher.write_u64(this_id);
                hasher.write_u64(i as u64);
                // Depth-first search
                element.inspect_child(this_id, search_id, ui);
            }
        }
    }

    fn contents_ui(&mut self, id: u64, selected: &mut Option<u64>, ui: &mut egui::Ui) {
        for (i, element) in self.into_iter().enumerate() {
            let mut hasher = std::collections::hash_map::DefaultHasher::default();
            hasher.write_u64(id);
            hasher.write_u64(i as u64);
            element.node_ui(&i.to_string(), hasher.finish(), selected, ui);
        }
    }
}

impl<T: TreeNode> TreeNode for Vec<T> {
    fn inspect_child(&mut self, this_id: u64, search_id: u64, ui: &mut egui::Ui) {
        if this_id == search_id {
            self.inspect_ui(ui);
        } else {
            for (i, element) in self.into_iter().enumerate() {
                let mut hasher = std::collections::hash_map::DefaultHasher::default();
                hasher.write_u64(this_id);
                hasher.write_u64(i as u64);
                // Depth-first search
                element.inspect_child(hasher.finish(), search_id, ui);
            }
        }
    }

    fn contents_ui(&mut self, id: u64, selected: &mut Option<u64>, ui: &mut egui::Ui) {
        for (i, element) in self.into_iter().enumerate() {
            let mut hasher = std::collections::hash_map::DefaultHasher::default();
            hasher.write_u64(id);
            hasher.write_u64(i as u64);
            element.node_ui(&i.to_string(), hasher.finish(), selected, ui);
        }
    }
}

impl<T: TreeNode + ?Sized> TreeNode for &mut T {
    fn inspect_child(&mut self, this_id: u64, search_id: u64, ui: &mut egui::Ui) {
        (*self).inspect_child(this_id, search_id, ui)
    }

    fn contents_ui(&mut self, id: u64, selected: &mut Option<u64>, ui: &mut egui::Ui) {
        (*self).contents_ui(id, selected, ui)
    }

    fn node_ui(&mut self, name: &str, id: u64, selected: &mut Option<u64>, ui: &mut egui::Ui) {
        (*self).node_ui(name, id, selected, ui)
    }
}

impl<T: TreeNode + ?Sized> TreeNode for Box<T> {
    fn inspect_child(&mut self, this_id: u64, search_id: u64, ui: &mut egui::Ui) {
        self.deref_mut().inspect_child(this_id, search_id, ui)
    }

    fn contents_ui(&mut self, id: u64, selected: &mut Option<u64>, ui: &mut egui::Ui) {
        self.deref_mut().contents_ui(id, selected, ui)
    }

    fn node_ui(&mut self, name: &str, id: u64, selected: &mut Option<u64>, ui: &mut egui::Ui) {
        self.deref_mut().node_ui(name, id, selected, ui)
    }
}