// Map, wardley map editor for linux
// Copyright (C) 2026 Rubén Beltrán del Río

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.

// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

// Suppress warnings from relm4 view! macro internals
#![allow(unused_assignments)]

mod actions;
mod constants;
mod dialogs;
mod file_registry;
mod handlers;
mod i18n;
mod preferences;
mod stages;
mod ui_helpers;

mod icon_names {
    #![allow(clippy::doc_markdown)] // Generated code from relm4_icons_build
    include!(concat!(env!("OUT_DIR"), "/icon_names.rs"));
}

use std::cell::RefCell;
use std::path::PathBuf;

use crate::actions::Action;
use crate::icon_names::shipped::{
    IMAGE_REGULAR, MENU_LARGE, SPLIT_HORIZONTAL_REGULAR, SPLIT_VERTICAL_REGULAR, ZOOM_IN_REGULAR,
    ZOOM_OUT_REGULAR,
};
use cairo::ImageSurface;
use gtk::gio;
use gtk::glib;
use gtk::prelude::*;
use relm4::{
    Component, ComponentController, ComponentParts, ComponentSender, RelmApp, RelmWidgetExt,
    SimpleComponent,
    actions::{AccelsPlus, ActionablePlus, RelmAction, RelmActionGroup},
    gtk,
};
use sourceview5::LanguageManager;
use sourceview5::prelude::{BufferExt, TextBufferExt, TextViewExt};
use stages::{ALL_STAGE_TYPES, LocalizedStageType};
use wmap_parser::{Map, parse};
use wmap_renderer::{Configuration, StageType, render_to_surface};

// Action group and action type declarations
relm4::new_action_group!(WindowActionGroup, "window");
relm4::new_stateless_action!(NewAction, WindowActionGroup, "new");
relm4::new_stateless_action!(OpenAction, WindowActionGroup, "open");
relm4::new_stateless_action!(SaveAction, WindowActionGroup, "save");
relm4::new_stateless_action!(SaveAsAction, WindowActionGroup, "save-as");
relm4::new_stateless_action!(CloseAction, WindowActionGroup, "close");
relm4::new_stateless_action!(ExportImageAction, WindowActionGroup, "export-image");
relm4::new_stateless_action!(
    ChangeOrientationAction,
    WindowActionGroup,
    "change-orientation"
);
relm4::new_stateless_action!(ZoomInAction, WindowActionGroup, "zoom-in");
relm4::new_stateless_action!(ZoomOutAction, WindowActionGroup, "zoom-out");
relm4::new_stateless_action!(PreferencesAction, WindowActionGroup, "preferences");

struct NewFromTemplateAction;
impl relm4::actions::ActionName for NewFromTemplateAction {
    type Group = WindowActionGroup;
    type Target = String;
    type State = ();

    const NAME: &'static str = "new-from-template";
}

/// Macro to reduce boilerplate when registering actions with accelerators.
macro_rules! register_action {
    ($group:expr, $app:expr, $sender:expr, $action_type:ty, $message:expr, $accelerators:expr) => {{
        let sender = $sender.clone();
        let action: RelmAction<$action_type> = RelmAction::new_stateless(move |_| {
            sender.input($message);
        });
        $group.add_action(action);
        $app.set_accelerators_for_action::<$action_type>($accelerators);
    }};
}

fn setup_actions(window: &gtk::Window, sender: &ComponentSender<AppModel>) {
    let application = relm4::main_application();
    let mut action_group = RelmActionGroup::<WindowActionGroup>::new();

    register_action!(
        action_group,
        application,
        sender,
        ZoomInAction,
        Action::ZoomIn,
        &["<Primary>equal", "<Primary>plus"]
    );
    register_action!(
        action_group,
        application,
        sender,
        ZoomOutAction,
        Action::ZoomOut,
        &["<Primary>minus"]
    );
    register_action!(
        action_group,
        application,
        sender,
        ChangeOrientationAction,
        Action::ChangeOrientation,
        &["<Primary>l"]
    );
    register_action!(
        action_group,
        application,
        sender,
        ExportImageAction,
        Action::ExportImage,
        &["<Primary>e"]
    );
    register_action!(
        action_group,
        application,
        sender,
        NewAction,
        Action::New,
        &["<Primary>n"]
    );
    register_action!(
        action_group,
        application,
        sender,
        SaveAction,
        Action::Save { close_after: false },
        &["<Primary>s"]
    );
    register_action!(
        action_group,
        application,
        sender,
        SaveAsAction,
        Action::SaveAs { close_after: false },
        &["<Primary><Shift>s"]
    );
    register_action!(
        action_group,
        application,
        sender,
        OpenAction,
        Action::Open,
        &["<Primary>o"]
    );
    register_action!(
        action_group,
        application,
        sender,
        CloseAction,
        Action::CloseWindow,
        &["<Primary>w"]
    );
    register_action!(
        action_group,
        application,
        sender,
        PreferencesAction,
        Action::ShowPreferences,
        &["<Primary>comma"]
    );

    let sender = sender.clone();
    let action: RelmAction<NewFromTemplateAction> =
        RelmAction::new_with_target_value(move |_, template_id| {
            sender.input(Action::NewFromTemplateById(template_id));
        });
    action_group.add_action(action);
    action_group.register_for_widget(window);
}

struct AppInit {
    zoom: f64,
    file_path: Option<PathBuf>,
    initial_content: Option<String>,
}

struct AppModel {
    orientation: gtk::Orientation,
    stage_type_list: gtk::StringList,
    available_stage_types: Vec<StageType>,
    stage_type: StageType,
    source: sourceview5::Buffer,
    source_view: sourceview5::View,
    map: Map,
    zoom: f64,
    render_configuration: Configuration,
    surface: ImageSurface,
    surface_width: i32,
    surface_height: i32,
    drawing_area: gtk::DrawingArea,
    current_file: Option<PathBuf>,
    modified: bool,
    pending_load_events: RefCell<u32>,
    initialized: bool,
    window: gtk::Window,
    preferences: preferences::UserPreferences,
    preferences_window: Option<relm4::Controller<preferences::PreferencesWindow>>,
    editor_css_provider: gtk::CssProvider,
    templates_menu: gio::Menu,
    main_menu: gio::Menu,
}

impl AppModel {
    #[allow(clippy::cast_possible_truncation)]
    fn update_image(&mut self) {
        if let Ok(surface) = render_to_surface(
            &self.map,
            &self.stage_type.to_localized(),
            &self.render_configuration,
        ) {
            self.surface_width = (f64::from(surface.width()) * self.zoom).round() as i32;
            self.surface_height = (f64::from(surface.height()) * self.zoom).round() as i32;
            self.surface = surface;

            let zoom = self.zoom;
            let surface_clone = self.surface.clone();
            self.drawing_area
                .set_draw_func(move |_, cr, _width, _height| {
                    cr.scale(zoom, zoom);
                    cr.set_source_surface(&surface_clone, 0.0, 0.0).ok();
                    cr.paint().ok();
                });

            self.drawing_area.set_content_width(self.surface_width);
            self.drawing_area.set_content_height(self.surface_height);
            self.drawing_area.queue_draw();
        }
    }

    fn window_title(&self) -> String {
        let default_name = tr!("document.untitled");
        let filename = self
            .current_file
            .as_ref()
            .and_then(|path| path.file_name())
            .and_then(|name| name.to_str())
            .unwrap_or(&default_name);

        if self.modified {
            format!("{}* - {}", filename, constants::APP_NAME)
        } else {
            format!("{} - {}", filename, constants::APP_NAME)
        }
    }

    fn is_empty_document(&self) -> bool {
        self.current_file.is_none() && !self.modified && self.source_text().is_empty()
    }

    fn source_text(&self) -> glib::GString {
        self.source
            .text(&self.source.start_iter(), &self.source.end_iter(), false)
    }

    fn set_source_text(&self, content: &str) {
        *self.pending_load_events.borrow_mut() += 1;
        self.source.set_text(content);
    }

    #[allow(clippy::cast_possible_truncation)]
    fn apply_preferences(&mut self) {
        self.source_view
            .set_wrap_mode(if self.preferences.soft_wrap_lines {
                gtk::WrapMode::Word
            } else {
                gtk::WrapMode::None
            });

        let css = if self.preferences.use_custom_editor_font {
            self.source_view.set_monospace(false);
            format!(
                "textview {{ font-family: \"{}\"; font-size: {}pt; }}",
                self.preferences.custom_editor_font_name, self.preferences.editor_font_size as i32
            )
        } else {
            self.source_view.set_monospace(true);
            format!(
                "textview {{ font-size: {}pt; }}",
                self.preferences.editor_font_size as i32
            )
        };

        self.editor_css_provider.load_from_data(&css);

        self.render_configuration.options.smart_label_positioning =
            self.preferences.use_smart_label_positioning;
        self.render_configuration.options.show_background = self.preferences.show_map_background;

        if self.preferences.use_custom_font {
            self.render_configuration.theme.fonts.face = self.preferences.custom_font_name.clone();
        } else {
            self.render_configuration.theme.fonts.face = String::from("sans-serif");
        }
    }

    fn rebuild_stage_type_list(&mut self) {
        let mut stage_types: Vec<StageType> = ALL_STAGE_TYPES.to_vec();

        for custom in &self.preferences.custom_stages {
            stage_types.push(StageType::Custom {
                name: custom.name.clone(),
                i: custom.stage.i.clone(),
                ii: custom.stage.ii.clone(),
                iii: custom.stage.iii.clone(),
                iv: custom.stage.iv.clone(),
            });
        }

        while self.stage_type_list.n_items() > 0 {
            self.stage_type_list.remove(0);
        }

        for stage_type in &stage_types {
            self.stage_type_list.append(&stage_type.localized_name());
        }

        self.available_stage_types = stage_types;
    }

    fn rebuild_templates_menu(&self) {
        self.templates_menu.remove_all();
        for template in &self.preferences.map_templates {
            self.templates_menu.append(
                Some(&template.name),
                Some(&format!("window.new-from-template::{}", template.id)),
            );
        }
    }

    pub fn open_new_window(file_path: Option<PathBuf>, initial_content: Option<String>) {
        let controller = AppModel::builder()
            .launch(AppInit {
                zoom: 1.0,
                file_path,
                initial_content,
            })
            .detach();

        let application = relm4::main_application();
        let window = controller.widget();
        application.add_window(window);
        window.present();

        file_registry::store_controller(controller);
    }

    fn init_stage_type_list() -> gtk::StringList {
        let stage_types: Vec<String> = ALL_STAGE_TYPES
            .iter()
            .map(stages::LocalizedStageType::localized_name)
            .collect();
        let stage_type_refs: Vec<&str> = stage_types
            .iter()
            .map(std::string::String::as_str)
            .collect();
        gtk::StringList::new(&stage_type_refs)
    }

    fn init_source_buffer(
        init: &AppInit,
        sender: &ComponentSender<Self>,
    ) -> (sourceview5::Buffer, String, Option<PathBuf>) {
        let source = sourceview5::Buffer::new(None);
        source.set_highlight_syntax(true);

        let language_manager = LanguageManager::default();
        if let Some(language) = language_manager.language("wmap") {
            source.set_language(Some(&language));
        }

        let (initial_content, current_file) = if let Some(ref path) = init.file_path {
            match std::fs::read_to_string(path) {
                Ok(content) => (content, Some(path.clone())),
                Err(_) => (String::new(), None),
            }
        } else {
            (init.initial_content.clone().unwrap_or_default(), None)
        };

        source.set_text(&initial_content);

        {
            let sender = sender.clone();
            source.connect_changed(move |_| {
                sender.input(Action::SourceChanged);
            });
        }

        (source, initial_content, current_file)
    }

    fn init_drawing_area(
        initial_content: &str,
    ) -> (
        gtk::DrawingArea,
        Map,
        Configuration,
        StageType,
        ImageSurface,
    ) {
        let drawing_area = gtk::DrawingArea::new();
        let map = parse(initial_content);
        let mut render_configuration = Configuration::default();
        let stage_type = StageType::Activities;
        render_configuration.options.smart_label_positioning = true;
        let surface = render_to_surface(&map, &stage_type.to_localized(), &render_configuration)
            .or_else(|_| ImageSurface::create(cairo::Format::ARgb32, 1, 1))
            .unwrap_or_else(|e| {
                eprintln!("Fatal: Cairo failed to create surface: {e}");
                std::process::exit(1);
            });

        (drawing_area, map, render_configuration, stage_type, surface)
    }

    fn init_main_menu(prefs: &preferences::UserPreferences) -> (gio::Menu, gio::Menu) {
        let templates_menu = gio::Menu::new();
        for template in &prefs.map_templates {
            templates_menu.append(
                Some(&template.name),
                Some(&format!("window.new-from-template::{}", template.id)),
            );
        }

        let main_menu = gio::Menu::new();
        main_menu.append(Some(&tr!("command.file.new")), Some("window.new"));
        main_menu.append_submenu(
            Some(&tr!("command.file.new_from_template")),
            &templates_menu,
        );
        main_menu.append(Some(&tr!("command.file.open")), Some("window.open"));
        main_menu.append(Some(&tr!("command.file.save")), Some("window.save"));
        main_menu.append(Some(&tr!("command.file.save_as")), Some("window.save-as"));
        main_menu.append(Some(&tr!("command.file.close")), Some("window.close"));
        main_menu.append(
            Some(&tr!("command.file.export")),
            Some("window.export-image"),
        );

        let layout_section = gio::Menu::new();
        layout_section.append(
            Some(&tr!("command.view.use_vertical_layout")),
            Some("window.change-orientation"),
        );
        main_menu.append_section(None, &layout_section);

        let zoom_section = gio::Menu::new();
        zoom_section.append(Some(&tr!("command.view.zoom_in")), Some("window.zoom-in"));
        zoom_section.append(Some(&tr!("command.view.zoom_out")), Some("window.zoom-out"));
        main_menu.append_section(None, &zoom_section);

        let prefs_section = gio::Menu::new();
        prefs_section.append(
            Some(&tr!("command.application.preferences")),
            Some("window.preferences"),
        );
        main_menu.append_section(None, &prefs_section);

        (templates_menu, main_menu)
    }
}

#[relm4::component]
impl SimpleComponent for AppModel {
    type Input = Action;
    type Output = ();
    type Init = AppInit;

    view! {
        #[root]
        gtk::Window {
            #[watch]
            set_title: Some(&model.window_title()),
            set_default_width: constants::DEFAULT_WINDOW_WIDTH,
            set_default_height: constants::DEFAULT_WINDOW_HEIGHT,

            gtk::Box {
                set_orientation: gtk::Orientation::Vertical,
                set_spacing: 0,

                gtk::HeaderBar {
                    pack_start = &gtk::Box {
                        set_orientation: gtk::Orientation::Horizontal,

                        gtk::Button::with_label(&match model.orientation {
                                gtk::Orientation::Horizontal => tr!("command.view.use_vertical_layout"),
                                _ => tr!("command.view.layout.use_horizontal_layout")
                            }) {
                            #[watch]
                            set_icon_name: match model.orientation {
                                gtk::Orientation::Horizontal => SPLIT_VERTICAL_REGULAR,
                                _ => SPLIT_HORIZONTAL_REGULAR
                            },
                            ActionablePlus::set_stateless_action::<ChangeOrientationAction>: &(),
                        }
                    },
                    pack_end = &gtk::Box {
                        set_orientation: gtk::Orientation::Horizontal,

                        gtk::Button::with_label(&tr!("command.file.export")) {
                            set_icon_name: IMAGE_REGULAR,
                            ActionablePlus::set_stateless_action::<ExportImageAction>: &(),
                        },

                        gtk::DropDown {
                            set_model: Some(&model.stage_type_list),
                            set_show_arrow: true,
                            set_selected: 0,
                            connect_selected_notify[sender] => move |dropdown| {
                                let selected = dropdown.selected();
                                sender.input(Action::StageTypeSelected(selected as usize));
                            },
                        },
                        gtk::MenuButton {
                            set_icon_name: MENU_LARGE,
                            #[wrap(Some)]
                            set_popover = &gtk::PopoverMenu::from_model(Some(&model.main_menu)) {}
                        }
                    }
                },

                gtk::Paned {
                    #[watch]
                    set_orientation: model.orientation,
                    set_expand: true,

                    #[wrap(Some)]
                    set_start_child = &gtk::ScrolledWindow {
                        #[local_ref]
                        source_view -> sourceview5::View {
                            set_expand: true,
                            set_buffer: Some(&model.source)
                        }
                    },

                    #[wrap(Some)]
                    set_end_child = &gtk::ScrolledWindow {
                        #[local_ref]
                        drawing_area -> gtk::DrawingArea {
                            #[watch]
                            set_content_width: model.surface_width,
                            #[watch]
                            set_content_height: model.surface_height
                        }
                    }
                },

                gtk::ActionBar {
                    pack_end = &gtk::Box {
                        set_orientation: gtk::Orientation::Horizontal,

                        gtk::Label {
                            #[watch]
                            set_label: &format!("{:.1}x", model.zoom),
                            set_margin_end: 5
                        },

                        gtk::Button::with_label(&tr!("command.view.zoom_out")) {
                            set_icon_name: ZOOM_OUT_REGULAR,
                            set_margin_end: 5,
                            add_css_class: "flat",
                            add_css_class: "zoom",
                            add_css_class: "zoom-out",
                            ActionablePlus::set_stateless_action::<ZoomOutAction>: &(),
                        },

                        gtk::Scale {
                            set_orientation: gtk::Orientation::Horizontal,
                            #[watch]
                            set_value: model.zoom,
                            set_draw_value: false,
                            set_range: (constants::MIN_ZOOM, constants::MAX_ZOOM),
                            set_increments: (constants::ZOOM_STEP, constants::ZOOM_STEP),
                            set_value_pos: gtk::PositionType::Left,
                            set_width_request: 100,
                            connect_value_changed[sender] => move |scale| {
                                sender.input(Action::Zoom(scale.value()));
                            }
                        },

                        gtk::Button::with_label(&tr!("command.view.zoom_in")) {
                            set_icon_name: ZOOM_IN_REGULAR,
                            add_css_class: "flat",
                            add_css_class: "zoom",
                            add_css_class: "zoom-in",
                            ActionablePlus::set_stateless_action::<ZoomInAction>: &(),
                        },
                    }
                }
            }
        }
    }

    fn init(
        init: Self::Init,
        root: Self::Root,
        sender: ComponentSender<Self>,
    ) -> ComponentParts<Self> {
        let stage_type_list = Self::init_stage_type_list();

        let (source, initial_content, current_file) = Self::init_source_buffer(&init, &sender);

        setup_actions(&root, &sender);

        let source_view = sourceview5::View::with_buffer(&source);
        source_view.set_monospace(true);

        let editor_css_provider = gtk::CssProvider::new();
        source_view.style_context().add_provider(
            &editor_css_provider,
            gtk::STYLE_PROVIDER_PRIORITY_APPLICATION,
        );

        let (drawing_area, map, render_configuration, stage_type, surface) =
            Self::init_drawing_area(&initial_content);

        if let Some(ref path) = current_file {
            file_registry::register_file(path, &root);
        }

        let prefs = preferences::storage::load();
        let (templates_menu, main_menu) = Self::init_main_menu(&prefs);

        let mut model = AppModel {
            orientation: gtk::Orientation::Horizontal,
            stage_type_list,
            available_stage_types: ALL_STAGE_TYPES.to_vec(),
            stage_type,
            source,
            source_view: source_view.clone(),
            map,
            zoom: init.zoom,
            render_configuration,
            surface,
            surface_width: 0,
            surface_height: 0,
            drawing_area: drawing_area.clone(),
            current_file,
            modified: false,
            pending_load_events: RefCell::new(0),
            initialized: false,
            window: root.clone(),
            preferences: prefs,
            preferences_window: None,
            editor_css_provider,
            templates_menu,
            main_menu,
        };

        model.apply_preferences();
        model.rebuild_stage_type_list();
        model.update_image();

        file_registry::register_sender(sender.input_sender().clone());

        {
            let sender = sender.clone();
            glib::idle_add_local_once(move || {
                sender.input(Action::MarkInitialized);
            });
        }

        {
            let sender = sender.clone();
            root.connect_close_request(move |_| {
                sender.input(Action::CloseWindow);
                glib::Propagation::Stop
            });
        }

        let widgets = view_output!();

        ComponentParts { model, widgets }
    }

    fn update(&mut self, message: Self::Input, sender: ComponentSender<Self>) {
        match message {
            Action::ChangeOrientation => handlers::view::change_orientation(self),
            Action::StageTypeSelected(index) => handlers::view::stage_type_selected(self, index),

            Action::SourceChanged => {
                let pending = *self.pending_load_events.borrow();
                if pending > 0 {
                    *self.pending_load_events.borrow_mut() -= 1;
                } else if self.initialized {
                    self.modified = true;
                }
                self.map = parse(&self.source_text());
                self.update_image();
            }

            Action::Zoom(level) => handlers::zoom::zoom(self, level),
            Action::ZoomIn => handlers::zoom::zoom_in(self),
            Action::ZoomOut => handlers::zoom::zoom_out(self),

            Action::ExportImage => {
                dialogs::show_export_dialog(&self.window, self.current_file.as_ref(), sender);
            }
            Action::ExportToFile { path, format } => {
                handlers::export::export_to_file(self, &path, format);
            }

            Action::New => {
                let content = self
                    .preferences
                    .map_templates
                    .iter()
                    .find(|t| t.is_default)
                    .map(|t| t.content.clone());
                Self::open_new_window(None, content);
            }
            Action::NewFromTemplateById(template_id) => {
                if let Ok(id) = uuid::Uuid::parse_str(&template_id)
                    && let Some(template) =
                        self.preferences.map_templates.iter().find(|t| t.id == id)
                {
                    Self::open_new_window(None, Some(template.content.clone()));
                }
            }
            Action::Open => {
                dialogs::show_open_dialog(&self.window, self.is_empty_document(), sender);
            }
            Action::Save { close_after } => handlers::file::save(self, close_after, &sender),
            Action::SaveAs { close_after } => dialogs::show_save_dialog(
                &self.window,
                self.current_file.as_ref(),
                close_after,
                sender,
            ),
            Action::LoadFile(path) => handlers::file::load_file(self, path),
            Action::SaveToFile { path, close_after } => {
                handlers::file::save_to_file(self, path, close_after);
            }
            Action::CloseWindow => handlers::file::close_window(self, &sender),

            Action::MarkInitialized => self.initialized = true,

            Action::ShowPreferences => {
                if self.preferences_window.is_none() {
                    let controller = preferences::PreferencesWindow::builder()
                        .transient_for(&self.window)
                        .launch(self.preferences.clone())
                        .forward(sender.input_sender(), |output| match output {
                            preferences::window::PreferencesOutput::PreferencesChanged(prefs) => {
                                Action::PreferencesChanged(prefs)
                            }
                            preferences::window::PreferencesOutput::Closed => {
                                Action::PreferencesWindowClosed
                            }
                        });
                    self.preferences_window = Some(controller);
                }
                if let Some(ref controller) = self.preferences_window {
                    controller.widget().present();
                }
            }
            Action::PreferencesChanged(prefs) => {
                self.preferences = prefs;
                self.apply_preferences();
                self.rebuild_stage_type_list();
                self.rebuild_templates_menu();
                self.update_image();
                file_registry::broadcast_to_all_windows(&Action::ReloadPreferences);
            }
            Action::PreferencesWindowClosed => {
                self.preferences_window = None;
            }
            Action::ReloadPreferences => {
                self.preferences = preferences::storage::load();
                self.apply_preferences();
                self.rebuild_stage_type_list();
                self.rebuild_templates_menu();
                self.update_image();
            }
        }
    }
}

fn main() {
    i18n::init();

    relm4_icons::initialize_icons(icon_names::GRESOURCE_BYTES, icon_names::RESOURCE_PREFIX);

    let prefs = preferences::storage::load();
    let initial_content = prefs
        .map_templates
        .iter()
        .find(|t| t.is_default)
        .map(|t| t.content.clone());

    let application = RelmApp::new(constants::APP_ID);
    application.run::<AppModel>(AppInit {
        zoom: 1.0,
        file_path: None,
        initial_content,
    });
}