use crate::color_scheme::ColorScheme;
use anyhow::Result;
use gtk::glib;
use gtk::prelude::*;
use gtk::{
    Box as GtkBox, ColorDialog, ColorDialogButton, InfoBar, Label, MessageType, Orientation,
    Picture, ScrolledWindow,
};
use std::cell::RefCell;
use std::path::Path;
use std::rc::Rc;

pub fn build_editor_page(icon_path: &Path, on_back: impl Fn() + 'static) -> Result<gtk::Widget> {
    let scheme = ColorScheme::load(icon_path)?;
    let scheme = Rc::new(RefCell::new(scheme));

    let root = GtkBox::new(Orientation::Vertical, 8);
    root.set_margin_top(8);
    root.set_margin_bottom(8);
    root.set_margin_start(8);
    root.set_margin_end(8);

    let toolbar = GtkBox::new(Orientation::Horizontal, 8);
    let back_button = gtk::Button::with_label("← Choose another icon");
    back_button.connect_clicked(move |_| on_back());
    toolbar.append(&back_button);

    let undo_button = gtk::Button::with_label("Undo");
    let redo_button = gtk::Button::with_label("Redo");
    toolbar.append(&undo_button);
    toolbar.append(&redo_button);
    root.append(&toolbar);

    if scheme.borrow().colors.is_empty() {
        let info = InfoBar::new();
        info.set_message_type(MessageType::Warning);
        info.add_child(&Label::new(Some(
            "No ColorScheme tags were found in this SVG.",
        )));
        root.append(&info);
    }

    let content = GtkBox::new(Orientation::Horizontal, 8);
    content.set_vexpand(true);

    let swatches_scroller = ScrolledWindow::new();
    swatches_scroller.set_min_content_width(300);
    let swatches_box = GtkBox::new(Orientation::Vertical, 4);
    swatches_scroller.set_child(Some(&swatches_box));
    content.append(&swatches_scroller);

    let preview = Picture::new();
    preview.set_hexpand(true);
    content.append(&preview);

    root.append(&content);

    let refresh_preview = {
        let scheme = Rc::clone(&scheme);
        let preview = preview.clone();
        move || {
            let bytes = glib::Bytes::from_owned(scheme.borrow().content.clone().into_bytes());
            match gtk::gdk::Texture::from_bytes(&bytes) {
                Ok(texture) => preview.set_paintable(Some(&texture)),
                Err(_) => preview.set_paintable(gtk::gdk::Paintable::NONE),
            }
        }
    };
    refresh_preview();

    let rebuild_swatches: Rc<RefCell<Box<dyn Fn()>>> = Rc::new(RefCell::new(Box::new(|| {})));
    {
        let scheme = Rc::clone(&scheme);
        let swatches_box = swatches_box.clone();
        let refresh_preview = refresh_preview.clone();
        let rebuild_swatches_for_closure = Rc::clone(&rebuild_swatches);

        let build_fn = move || {
            while let Some(child) = swatches_box.first_child() {
                swatches_box.remove(&child);
            }

            let tags: Vec<(String, String)> = scheme.borrow().colors.clone();
            for (tag, hex) in tags {
                let row = GtkBox::new(Orientation::Horizontal, 8);
                let label = Label::new(Some(&tag));
                label.set_hexpand(true);
                label.set_xalign(0.0);

                let rgba = gtk::gdk::RGBA::parse(&hex).unwrap_or(gtk::gdk::RGBA::BLACK);
                let dialog = ColorDialog::builder().with_alpha(false).build();
                let button = ColorDialogButton::new(Some(dialog));
                button.set_rgba(&rgba);

                {
                    let scheme = Rc::clone(&scheme);
                    let tag = tag.clone();
                    let refresh_preview = refresh_preview.clone();
                    let rebuild_swatches_for_closure = Rc::clone(&rebuild_swatches_for_closure);
                    button.connect_rgba_notify(move |btn| {
                        let new_rgba = btn.rgba();
                        let new_hex = format!(
                            "#{:02x}{:02x}{:02x}",
                            (new_rgba.red() * 255.0).round() as u8,
                            (new_rgba.green() * 255.0).round() as u8,
                            (new_rgba.blue() * 255.0).round() as u8,
                        );
                        let changed = scheme
                            .borrow_mut()
                            .update_color(&tag, &new_hex)
                            .unwrap_or(false);
                        if changed {
                            refresh_preview();
                            (rebuild_swatches_for_closure.borrow())();
                        }
                    });
                }

                row.append(&label);
                row.append(&button);
                swatches_box.append(&row);
            }
        };

        *rebuild_swatches.borrow_mut() = Box::new(build_fn);
    }
    (rebuild_swatches.borrow())();

    {
        let scheme = Rc::clone(&scheme);
        let refresh_preview = refresh_preview.clone();
        let rebuild_swatches = Rc::clone(&rebuild_swatches);
        undo_button.connect_clicked(move |_| {
            if scheme.borrow_mut().undo().unwrap_or(false) {
                refresh_preview();
                (rebuild_swatches.borrow())();
            }
        });
    }
    {
        let scheme = Rc::clone(&scheme);
        let refresh_preview = refresh_preview.clone();
        let rebuild_swatches = Rc::clone(&rebuild_swatches);
        redo_button.connect_clicked(move |_| {
            if scheme.borrow_mut().redo().unwrap_or(false) {
                refresh_preview();
                (rebuild_swatches.borrow())();
            }
        });
    }

    Ok(root.upcast())
}