use std::path::PathBuf;
use std::time::Duration;
use adw::prelude::{WidgetExt, AdwApplicationWindowExt, Cast};
use gtk::prelude::{BoxExt, ButtonExt, GtkWindowExt, OrientableExt};
use relm4::actions::{AccelsPlus, RelmActionGroup, RelmAction};
use relm4::*;
use relm4::factory::FactoryVecDeque;
use relm4_components::{save_dialog::*, open_dialog::*};
use mossfets_game_of_life::game::{Game, Coord};
use crate::factory::cell::Cell;
use crate::widgets::runner::{RunModel, RunMsg, RunOutput};
use crate::widgets::preferences::{PreferencesModel, PreferencesMsg};

/// The model representing the application's state
#[tracker::track]
pub struct AppModel {
    #[do_not_track]
    pub game: Game,
    #[do_not_track]
    pub size: (Coord, Coord),
    #[do_not_track]
    running: bool,
    #[do_not_track]
    offset: Coord,
    toast: Option<adw::Toast>,
    #[do_not_track]
    pub cells: FactoryVecDeque<Cell>,
    #[do_not_track]
    runner: Controller<RunModel>,
    #[do_not_track]
    preferences: Controller<PreferencesModel>,
    #[do_not_track]
    save_dialog: Controller<SaveDialog>,
    #[do_not_track]
    open_dialog: Controller<OpenDialog>,
}

/// The messages given the the model to update its state
#[derive(Debug)]
pub enum AppMsg {
    Advance,
    Revert,
    ChangeAtPoint(Coord),
    ChangeAtGridSpacePoint(Coord),
    Move(Direction),
    Sync,
    Toggle,
    Size(Coord),
    Clear,
    SaveRequest,
    OpenRequest,
    SaveResponse(PathBuf),
    OpenResponse(PathBuf),
    ShowPreferences,
}

/// A direction to move the view of the grid
#[derive(Debug)]
pub enum Direction {
    Up,
    Down,
    Left,
    Right,
}

impl AppModel {
    /// Convert from a space on the visible grid (starting from 0,0 in top-left) to the board's
    /// coordinate system
    pub fn to_game_space(&self, coord: Coord) -> Coord {
        let c1 = self.size.0;
        (c1.0 + coord.0 + self.offset.0, c1.1 + coord.1 + self.offset.1)
    }
    /// Modify the factory vector to fit only cells in the appropriate range
    pub fn size(&mut self, c1: Coord, c2: Coord) {
        let mut cells_guard = self.cells.guard();
        cells_guard.clear();
        for i in 0..c2.0-c1.0 + 1 {
            for j in 0..c2.1-c1.1 + 1 {
                cells_guard.push_back(((i, j), false));
            }
        }
        self.size = (c1, c2);
    }

    /// Modify the cells of the factory to match the game's state
    pub fn sync(&mut self) {
        let c1 = (self.size.0.0 + self.offset.0, self.size.0.1 + self.offset.1);
        let c2 = (self.size.1.0 + self.offset.0, self.size.1.1 + self.offset.1);
        let view = self.game.get_view(c1, c2);
        let len = self.cells.len();
        let mut cells_guard = self.cells.guard();
        for index in 0..len { 
            let cell = cells_guard.get_mut(index).unwrap();
            let coord = cell.get_coordinate();
            let coord = (coord.0 + c1.0, coord.1 + c1.1);
            if view.contains(&&coord) {
                cell.value = true;
            } else {
                cell.value = false;
            }
        }
    }

    fn observe_window(sender: &ComponentSender<Self>, window: &adw::ApplicationWindow, exit_fullscreen: bool) {
        let window = window.clone();
        let sender = sender.clone();
        spawn_local(async move {
            async_std::task::sleep(Duration::from_millis(25)).await;
            if exit_fullscreen && (window.is_maximized() || window.is_fullscreened()) { return };
            let (x, y) = (window.width(), window.height());
            if x == 0 || y == 0 { return };
            sender.input(AppMsg::Size((x as isize, y as isize)));
        });
    }
}

#[relm4::component(pub)]
impl SimpleComponent for AppModel {
    type Widgets = AppWidgets;
    type Init = Game;
    type Input = AppMsg;
    type Output = ();

    view! {
        main_window = adw::ApplicationWindow {
            set_title: Some("Game of Life"),
            set_default_width: 600,
            set_default_height: 500,
            #[wrap(Some)]
            set_content: toast_overlay = &adw::ToastOverlay {
                #[wrap(Some)]
                set_child = &gtk::Box {
                    set_orientation: gtk::Orientation::Vertical,
                    append = &adw::HeaderBar {
                        set_show_start_title_buttons: true,
                        // Main menu
                        pack_end = &gtk::MenuButton {
                            set_tooltip_text: Some("Main Menu"),
                            set_icon_name: "open-menu-symbolic",
                            set_menu_model: Some(&main_menu),
                            set_primary: true,
                        },
                        // Window controls
                        #[wrap(Some)]
                        set_title_widget = &gtk::Box {
                            set_orientation: gtk::Orientation::Horizontal,
                            append: prev = &gtk::Button {
                                set_tooltip_text: Some("Step Backward"),
                                set_icon_name: "go-previous-symbolic",
                                connect_clicked[sender] => move |_| {
                                    sender.input(AppMsg::Revert)
                                }
                            },
                            append = &gtk::Button {
                                set_tooltip_text: Some("Step Forward"),
                                set_icon_name: "go-next-symbolic",
                                connect_clicked[sender] => move |_| {
                                    sender.input(AppMsg::Advance);
                                },
                            },
                            // Runner component has to be inserted after everything else
                            insert_child_after[Some(&prev)]: model.runner.widget(),
                        },
                        set_show_end_title_buttons: true,
                    },

                    gtk::Overlay {
                        add_overlay = &gtk::AspectFrame {
                            #[local_ref]
                            #[wrap(Some)]
                            set_child = cell_grid -> gtk::Grid {
                                set_valign: gtk::Align::Center,
                                set_halign: gtk::Align::Center,
                            }
                        },
                        #[wrap(Some)]
                        set_child = &gtk::Box {
                            set_height_request: 200,
                            set_width_request: 300,
                        }
                    }
                }
            }
        }
    }
    // The application's main menu
    menu! {
        main_menu: {
            "_Clear" => ClearAction,
            "_Open File" => OpenAction,
            "_Save File" => SaveAction,
            "_Preferences" => PreferencesAction,
            "_About" => AboutAction,
        }
    }
    fn init(
        init: Self::Init,
        root: &Self::Root,
        sender: ComponentSender<Self>,
        ) -> ComponentParts<Self> {
        let game = init;
        let runner = RunModel::builder()
            .launch(())
            .forward(sender.input_sender(), 
                    |msg| match msg {
                        RunOutput::Advance => AppMsg::Advance,
                    });
        let open_dialog = OpenDialog::builder()
            .transient_for_native(root)
            .launch(OpenDialogSettings::default())
            .forward(sender.input_sender(), |response| match response {
                OpenDialogResponse::Accept(path) => AppMsg::OpenResponse(path),
                OpenDialogResponse::Cancel => AppMsg::Sync,
            });

        let save_dialog = SaveDialog::builder()
            .transient_for_native(root)
            .launch(SaveDialogSettings::default())
            .forward(sender.input_sender(), |response| match response {
                SaveDialogResponse::Accept(path) => AppMsg::SaveResponse(path),
                SaveDialogResponse::Cancel => AppMsg::Sync,
            });
        let preferences = PreferencesModel::builder()
            .launch(root.clone().upcast())
            .forward(sender.input_sender(), |_| AppMsg::Sync);
        let model = AppModel { 
            cells: FactoryVecDeque::new(gtk::Grid::default(), sender.input_sender()), 
            game, 
            size: ((-1, -1), (1, 1)), 
            running: false, 
            toast: None, 
            tracker: 0, 
            offset: (0,0), 
            runner, 
            open_dialog, 
            save_dialog, 
            preferences,
        };
        let cell_grid = model.cells.widget();
        let widgets = view_output!();
        let app = relm4::main_application();
        app.set_accelerators_for_action::<UpAction>(&["k", "w", "Up"]);
        app.set_accelerators_for_action::<DownAction>(&["j", "s", "Down"]);
        app.set_accelerators_for_action::<RightAction>(&["l", "d", "Right"]);
        app.set_accelerators_for_action::<LeftAction>(&["h", "a", "Left"]);

        let group = RelmActionGroup::<WindowActionGroup>::new();
        let sender_clone = sender.clone();
        let action: RelmAction<UpAction> = RelmAction::new_stateless(move |_| {
            sender_clone.input(AppMsg::Move(Direction::Up));
        });
        let sender_clone = sender.clone();
        let action2: RelmAction<DownAction> = RelmAction::new_stateless(move |_| {
            sender_clone.input(AppMsg::Move(Direction::Down));
        });
        let sender_clone = sender.clone();
        let action3: RelmAction<LeftAction> = RelmAction::new_stateless(move |_| {
            sender_clone.input(AppMsg::Move(Direction::Left));
        });
        let sender_clone = sender.clone();
        let action4: RelmAction<RightAction> = RelmAction::new_stateless(move |_| {
            sender_clone.input(AppMsg::Move(Direction::Right));
        });
        let sender_clone = sender.clone();
        let action5: RelmAction<ClearAction> = RelmAction::new_stateless(move |_| {
            sender_clone.input(AppMsg::Clear);
        });
        let sender_clone = sender.clone();
        let action6: RelmAction<OpenAction> = RelmAction::new_stateless(move |_| {
            sender_clone.input(AppMsg::OpenRequest);
        });
        let sender_clone = sender.clone();
        let action7: RelmAction<SaveAction> = RelmAction::new_stateless(move |_| {
            sender_clone.input(AppMsg::SaveRequest);
        });

        // Open the about menu
        let action8: RelmAction<AboutAction> = RelmAction::new_stateless(move |_| {
            adw::builders::AboutWindowBuilder::new()
                .copyright("Copyright. Mossfet")
                .license_type(gtk::License::Gpl30)
                .application_name("Life")
                .comments("A GTK4 Conway's Game of Life emulator")
                .title("About Life")
                .developer_name("Mossfet")
                .application_icon("view-app-grid-symbolic")
                .height_request(600)
                .width_request(360)
                .build()
                .show();
        });

        let sender_clone = sender.clone();
        let action9: RelmAction<PreferencesAction> = RelmAction::new_stateless(move |_| {
            sender_clone.input(AppMsg::ShowPreferences);
        });


        group.add_action(&action);
        group.add_action(&action2);
        group.add_action(&action3);
        group.add_action(&action4);
        group.add_action(&action5);
        group.add_action(&action6);
        group.add_action(&action7);
        group.add_action(&action8);
        group.add_action(&action9);

        let actions = group.into_action_group();
        widgets.main_window.insert_action_group("win", Some(&actions));
        let sender_clone = sender.clone();
        widgets.main_window.connect_default_height_notify(move |window| {
            AppModel::observe_window(&sender_clone, &window, true);
        });
        let sender_clone = sender.clone();
        widgets.main_window.connect_default_width_notify(move |window| {
            AppModel::observe_window(&sender_clone, &window, true);
        });
        let sender_clone = sender.clone();
        widgets.main_window.connect_maximized_notify(move |window| {
            AppModel::observe_window(&sender_clone, &window, false);
        });

        let sender_clone = sender.clone();
        AppModel::observe_window(&sender_clone, &widgets.main_window, false);

        sender.input(AppMsg::Sync);
        ComponentParts { model, widgets }
    }
    fn update(
        &mut self,
        msg: Self::Input,
        _sender: ComponentSender<Self>,
        ) {
        self.reset();
        match msg {
            AppMsg::Size(c) => {
                let (width, height) = c;
                let mut horizontal_count = width/56;
                // If there are less than 15 pixels of free horizontal space, shrink the grid
                if width%56 < 2 {
                    horizontal_count -= 1;
                }
                let mut vertical_count = height/56;
                // If there are less than 15 pixels of free vertical space (offset to include
                // headerbar), shrink the grid
                if (height%56 - 47) < 1 {
                    vertical_count -= 1;
                }
                // When there is an even number of rows/columns, the origin should be left/above
                // the center. 
                //println!("{}, {}", horizontal_count, vertical_count);
                let c1 = (-(horizontal_count.div_ceil(2)-1), -(vertical_count.div_ceil(2)-1));
                let c2 = (horizontal_count/2, vertical_count/2);
                if (c1, c2) != self.size {
                    self.size(c1, c2);
                }
            }
            AppMsg::Advance => {
                self.game.advance_board();
            }
            AppMsg::Revert => {
                self.game.revert_board();
            }
            AppMsg::ChangeAtPoint(coord) => {
                self.game.flip_state(coord);
            }
            AppMsg::ChangeAtGridSpacePoint(coord) => {
                self.game.flip_state(self.to_game_space(coord));
            }
            AppMsg::Move(direction) => {
                let mut offset = self.offset;
                match direction {
                    Direction::Left => {
                        offset = (offset.0 - 1, offset.1);
                    }
                    Direction::Right => {
                        offset = (offset.0 + 1, offset.1);
                    }
                    Direction::Up => {
                        offset = (offset.0, offset.1 - 1);
                    }
                    Direction::Down => {
                        offset = (offset.0, offset.1 + 1);
                    }
                }
                self.offset = offset;
            }
            AppMsg::Sync => {}
            AppMsg::Toggle => {
                self.runner.emit(RunMsg::Toggle);
                self.running = !self.running;
            }
            AppMsg::Clear => {
                self.game = Game::new();
            }
            AppMsg::SaveRequest => {
                self.save_dialog.emit(SaveDialogMsg::SaveAs(format!("pattern.lif")));
            }
            AppMsg::OpenRequest => {
                self.open_dialog.emit(OpenDialogMsg::Open);
            }
            AppMsg::SaveResponse(path) => {
                match mossfets_game_of_life::writer::write_game_at_path(path, &self.game) {
                    Ok(_) => {},
                    Err(_) => self.set_toast(Some(adw::Toast::builder().title("Failed to write file!").priority(adw::ToastPriority::High).build())),
                }
            },
            AppMsg::OpenResponse(path) => {
                let path = path.to_str().unwrap();
                match mossfets_game_of_life::reader::read_game_at_path(path) {
                    Ok(game) => self.game = game,
                    Err(_) => self.set_toast(Some(adw::Toast::builder().title("Failed to read file!").priority(adw::ToastPriority::High).build())),
                }
            }
            AppMsg::ShowPreferences => {
                self.preferences.emit(PreferencesMsg::Show);
            }
            /*AppMsg::SetDark(theme_enabled) => {
              let style = adw::StyleManager::default();
              match theme_enabled {
              ThemeVariant::Dark => {
              style.set_color_scheme(adw::ColorScheme::PreferDark);
              }
              ThemeVariant::Light => {
              style.set_color_scheme(adw::ColorScheme::PreferLight);
              }
              ThemeVariant::Default => {
              style.set_color_scheme(adw::ColorScheme::Default);
              }
              }
              }*/
        }
        self.sync();
    }

    fn pre_view() {
        if model.changed(AppModel::toast()) {
            toast_overlay.add_toast(model.toast.as_ref().unwrap());
            sender.input(AppMsg::Sync);
        }
    }
}

/*fn setup_action<T, F, U> (sender: Sender<T>, f: F, group: RelmActionGroup<U>)
  where F: Fn(&gio::SimpleAction) + 'static,
  U: ActionGroupName 
  {
  let sender = sender.clone();
  let action: RelmAction<U> = RelmAction::new_stateless(f);
  group.add_action(action);

  }*/
relm4::new_action_group!(WindowActionGroup, "win");
relm4::new_stateless_action!(UpAction, WindowActionGroup, "up");
relm4::new_stateless_action!(DownAction, WindowActionGroup, "down");
relm4::new_stateless_action!(LeftAction, WindowActionGroup, "left");
relm4::new_stateless_action!(RightAction, WindowActionGroup, "right");
relm4::new_stateless_action!(ClearAction, WindowActionGroup, "clear");
relm4::new_stateless_action!(OpenAction, WindowActionGroup, "open-file");
relm4::new_stateless_action!(SaveAction, WindowActionGroup, "save");
relm4::new_stateless_action!(AboutAction, WindowActionGroup, "about");
relm4::new_stateless_action!(PreferencesAction, WindowActionGroup, "preferences");