// 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
mod actions;
mod components;
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::convert::identity;
use std::path::PathBuf;

use crate::actions::Action;
use adw::prelude::*;
use cairo::ImageSurface;
use gtk::glib;
use relm4::actions::{AccelsPlus, RelmAction, RelmActionGroup};
use relm4::prelude::*;

use sourceview5::LanguageManager;
use sourceview5::prelude::*;

use stages::LocalizedStageType;
use wmap_parser::{Map, parse};
use wmap_renderer::{Configuration, StageType, render_to_surface};

use components::footer::{Footer, FooterInit};
use components::header::{Header, HeaderInit};

/// 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 |_| {
            let _ = sender.input($message);
        });
        $group.add_action(action.clone());
        $app.set_accelerators_for_action::<$action_type>($accelerators);
        action
    }};
}

/// Macro to further reduce the boilerplate, by allowing terser registration.
macro_rules! register_actions {
    ($group:expr, $app:expr, $sender:expr, [
        $( $action_type:ty => $message:expr, $accelerators:expr );+ $(;)?
    ]) => {{
        $(
            register_action!(
                $group, $app, $sender,
                $action_type, $message, $accelerators
            );
        )+
    }};
}

// 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";
}

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

struct AppModel {
    orientation: gtk::Orientation,
    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: adw::Window,
    preferences: preferences::UserPreferences,
    preferences_window: Option<relm4::Controller<preferences::PreferencesWindow>>,
    editor_css_provider: gtk::CssProvider,
    horizontal_layout_enabled: bool,
    // Child Components
    header: Controller<Header>,
    footer: Controller<Footer>,
}

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!(
                ".map-editor {{ 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!(
                ".map-editor {{ font-size: {}pt; }}",
                self.preferences.editor_font_size as i32
            )
        };

        self.editor_css_provider.load_from_string(&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");
        }
    }

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

    // Initialize the buffer that will be used to hold and read the source code.
    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)
    }

    // Initializes the Source View that shows the colorized text.
    fn init_source_view(source: &sourceview5::Buffer) -> (sourceview5::View, gtk::CssProvider) {
        let source_view = sourceview5::View::with_buffer(source);
        source_view.set_monospace(true);

        let editor_css_provider = gtk::CssProvider::new();
        source_view.add_css_class("map-editor");
        if let Some(display) = gtk::gdk::Display::default() {
            gtk::style_context_add_provider_for_display(
                &display,
                &editor_css_provider,
                gtk::STYLE_PROVIDER_PRIORITY_APPLICATION,
            );
        }
        (source_view, editor_css_provider)
    }

    // Initializes the drawing area that shows the rendered map.
    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)
    }

    // Initializes the breakpoint logic
    fn init_breakpoints(sender: &ComponentSender<Self>, root: &adw::Window) {
        let breakpoint = adw::Breakpoint::new(adw::BreakpointCondition::new_length(
            adw::BreakpointConditionLengthType::MinWidth,
            440.0,
            adw::LengthUnit::Sp,
        ));
        {
            let sender = sender.clone();
            breakpoint.connect_apply(move |_| {
                sender.input(Action::EnableHorizontalLayout);
            });
        }

        {
            let sender = sender.clone();
            breakpoint.connect_unapply(move |_| {
                sender.input(Action::DisableHorizontalLayout);
            });
        }
        root.add_breakpoint(breakpoint);
    }
}

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

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

            adw::ToolbarView {
                add_top_bar = model.header.widget(),

                gtk::Paned {
                    #[watch]
                    set_orientation: if model.horizontal_layout_enabled { model.orientation } else { gtk::Orientation::Vertical },
                    set_expand: true,

                    #[wrap(Some)]
                    set_start_child = &gtk::ScrolledWindow {
                        #[local_ref]
                        source_view -> sourceview5::View {
                            set_expand: true,
                            set_buffer: Some(&model.source),
                            set_top_margin: 8,
                            set_bottom_margin: 8,
                            set_left_margin: 8,
                            set_right_margin: 8
                        }
                    },

                    #[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
                        }
                    }
                },

                add_bottom_bar = model.footer.widget(),
            }
        }
    }

    fn init(
        init: Self::Init,
        root: Self::Root,
        sender: ComponentSender<Self>,
    ) -> ComponentParts<Self> {
        let (source, initial_content, current_file) = Self::init_source_buffer(&init, &sender);
        let (source_view, editor_css_provider) = Self::init_source_view(&source);
        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 preferences = preferences::storage::load();

        let horizontal_layout_enabled = false;

        // Actions
        let application = relm4::main_application();
        let mut action_group = RelmActionGroup::<WindowActionGroup>::new();

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

        {
            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(&root);
        }

        // Child Components
        let header = Header::builder()
            .launch(HeaderInit {
                layout_action,
                custom_stages: preferences.custom_stages.clone(),
                templates: preferences.map_templates.clone(),
                orientation: init.orientation,
                horizontal_layout_enabled,
            })
            .forward(sender.input_sender(), identity);

        let footer = Footer::builder()
            .launch(FooterInit { zoom: init.zoom })
            .forward(sender.input_sender(), identity);

        let mut model = AppModel {
            orientation: init.orientation,
            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,
            preferences_window: None,
            editor_css_provider,
            horizontal_layout_enabled: true,
            header,
            footer,
        };

        model.apply_preferences();
        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!();

        // Breakpoints for Smaller Layouts
        Self::init_breakpoints(&sender, &root);
        ComponentParts { model, widgets }
    }

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

            // Layout Transition
            Action::DisableHorizontalLayout => {
                handlers::view::change_horizontal_layout(self, false);
            }
            Action::EnableHorizontalLayout => handlers::view::change_horizontal_layout(self, true),

            // Preferences
            Action::ShowPreferences => handlers::preferences::show(self, &sender),
            Action::PreferencesChanged(preferences) => {
                handlers::preferences::update(self, preferences);
            }
            Action::PreferencesWindowClosed => handlers::preferences::close(self),
            Action::ReloadPreferences => handlers::preferences::reload(self),
        }
    }
}

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

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

    let preferences = preferences::storage::load();
    let initial_content = preferences
        .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,
        orientation: gtk::Orientation::Horizontal,
        file_path: None,
        initial_content,
    });
}