//! Dialog helper functions for file operations and error display.

use std::path::PathBuf;

use gtk::prelude::*;
use relm4::{ComponentSender, gtk};

use crate::actions::Action;
use crate::constants;
use crate::file_registry;
use crate::AppModel;

/// Creates a file filter for .wmap files.
pub fn create_file_filter() -> gtk::FileFilter {
    let filter = gtk::FileFilter::new();
    filter.add_pattern(&format!("*.{}", constants::FILE_EXTENSION));
    filter.add_mime_type(constants::MIME_TYPE);
    filter.set_name(Some("Wardley Map Files"));
    filter
}

/// Shows an error dialog with the given title and message.
pub fn show_error(window: &gtk::Window, title: &str, message: &str) {
    let dialog = gtk::MessageDialog::new(
        Some(window),
        gtk::DialogFlags::MODAL | gtk::DialogFlags::DESTROY_WITH_PARENT,
        gtk::MessageType::Error,
        gtk::ButtonsType::Ok,
        message,
    );
    dialog.set_title(Some(title));
    dialog.connect_response(|dialog, _| {
        dialog.close();
    });
    dialog.show();
}

/// Shows a file open dialog and handles the response.
pub fn show_open_dialog(
    window: &gtk::Window,
    is_empty_document: bool,
    sender: ComponentSender<AppModel>,
) {
    let dialog = gtk::FileChooserDialog::new(
        Some("Open Map"),
        Some(window),
        gtk::FileChooserAction::Open,
        &[
            ("Cancel", gtk::ResponseType::Cancel),
            ("Open", gtk::ResponseType::Accept),
        ],
    );
    dialog.add_filter(&create_file_filter());

    dialog.connect_response(move |dialog, response| {
        dialog.close();
        if response == gtk::ResponseType::Accept
            && let Some(file) = dialog.file()
            && let Some(path) = file.path()
        {
            // Check if file is already open - if so, focus that window
            if let Some(existing_window) = file_registry::find_window_for_file(&path) {
                existing_window.present();
                return;
            }

            if is_empty_document {
                sender.input(Action::LoadFile(path));
            } else {
                AppModel::open_new_window(Some(path));
            }
        }
    });
    dialog.present();
}

/// Shows a file save dialog and handles the response.
pub fn show_save_dialog(
    window: &gtk::Window,
    current_file: Option<PathBuf>,
    close_after: bool,
    sender: ComponentSender<AppModel>,
) {
    let dialog = gtk::FileChooserDialog::new(
        Some("Save Map As"),
        Some(window),
        gtk::FileChooserAction::Save,
        &[
            ("Cancel", gtk::ResponseType::Cancel),
            ("Save", gtk::ResponseType::Accept),
        ],
    );
    dialog.add_filter(&create_file_filter());

    if let Some(ref current_path) = current_file {
        if let Some(parent) = current_path.parent() {
            let folder = gtk::gio::File::for_path(parent);
            dialog.set_current_folder(Some(&folder)).ok();
        }
        if let Some(filename) = current_path.file_name() {
            dialog.set_current_name(filename.to_str().unwrap_or("map.wmap"));
        }
    } else {
        dialog.set_current_name("map.wmap");
    }

    dialog.connect_response(move |dialog, response| {
        dialog.close();
        if response == gtk::ResponseType::Accept
            && let Some(file) = dialog.file()
            && let Some(path) = file.path()
        {
            sender.input(Action::SaveToFile { path, close_after });
        }
    });
    dialog.present();
}

/// Shows a dialog asking whether to save unsaved changes before closing.
pub fn show_unsaved_changes_dialog(
    window: &gtk::Window,
    current_file: Option<PathBuf>,
    sender: ComponentSender<AppModel>,
) {
    let dialog = gtk::MessageDialog::new(
        Some(window),
        gtk::DialogFlags::MODAL | gtk::DialogFlags::DESTROY_WITH_PARENT,
        gtk::MessageType::Warning,
        gtk::ButtonsType::None,
        "Save changes before closing?",
    );
    dialog.set_title(Some("Unsaved Changes"));
    dialog.add_button("Don't Save", gtk::ResponseType::Reject);
    dialog.add_button("Cancel", gtk::ResponseType::Cancel);
    dialog.add_button("Save", gtk::ResponseType::Accept);

    let window = window.clone();
    dialog.connect_response(move |dialog, response| {
        dialog.close();
        match response {
            gtk::ResponseType::Accept => {
                if current_file.is_some() {
                    sender.input(Action::Save { close_after: true });
                } else {
                    sender.input(Action::SaveAs { close_after: true });
                }
            }
            gtk::ResponseType::Reject => {
                if let Some(ref path) = current_file {
                    file_registry::unregister_file(path);
                }
                window.destroy();
            }
            _ => {}
        }
    });
    dialog.show();
}