use crate::{
    accounts::render_accounts_route,
    actionbar::NoteAction,
    app_style::{get_font_size, NotedeckTextStyle},
    fonts::NamedFontFamily,
    notes_holder::NotesHolder,
    profile::Profile,
    relay_pool_manager::RelayPoolManager,
    route::Route,
    storage::{self},
    thread::Thread,
    timeline::{
        route::{render_timeline_route, TimelineRoute},
        Timeline,
    },
    ui::{
        self,
        add_column::render_add_column_routes,
        anim::{AnimationHelper, ICON_EXPANSION_MULTIPLE},
        note::{PostAction, PostType},
        support::SupportView,
        RelayView, View,
    },
    Damus,
};

use egui::{pos2, Color32, InnerResponse, Stroke};
use egui_nav::{Nav, NavAction, NavResponse, TitleBarResponse};
use nostrdb::{Ndb, Transaction};
use tracing::{error, info};

pub enum RenderNavAction {
    PostAction(PostAction),
    NoteAction(NoteAction),
}

impl From<PostAction> for RenderNavAction {
    fn from(post_action: PostAction) -> Self {
        Self::PostAction(post_action)
    }
}

impl From<NoteAction> for RenderNavAction {
    fn from(note_action: NoteAction) -> RenderNavAction {
        Self::NoteAction(note_action)
    }
}

pub struct RenderNavResponse {
    column: usize,
    response: NavResponse<Option<RenderNavAction>, TitleResponse>,
}

impl RenderNavResponse {
    #[allow(private_interfaces)]
    pub fn new(
        column: usize,
        response: NavResponse<Option<RenderNavAction>, TitleResponse>,
    ) -> Self {
        RenderNavResponse { column, response }
    }

    pub fn process_render_nav_response(&self, app: &mut Damus) {
        let mut col_changed: bool = false;
        let col = self.column;

        if let Some(action) = &self.response.inner {
            // start returning when we're finished posting
            match action {
                RenderNavAction::PostAction(post_action) => {
                    let txn = Transaction::new(&app.ndb).expect("txn");
                    let _ = post_action.execute(&app.ndb, &txn, &mut app.pool, &mut app.drafts);
                    app.columns_mut().column_mut(col).router_mut().go_back();
                }

                RenderNavAction::NoteAction(note_action) => {
                    let txn = Transaction::new(&app.ndb).expect("txn");

                    note_action.execute_and_process_result(
                        &app.ndb,
                        &mut app.columns,
                        col,
                        &mut app.threads,
                        &mut app.profiles,
                        &mut app.note_cache,
                        &mut app.pool,
                        &txn,
                    );
                }
            }
        }

        if let Some(NavAction::Returned) = self.response.action {
            let r = app.columns_mut().column_mut(col).router_mut().pop();
            let txn = Transaction::new(&app.ndb).expect("txn");
            if let Some(Route::Timeline(TimelineRoute::Thread(id))) = r {
                let root_id = {
                    crate::note::root_note_id_from_selected_id(
                        &app.ndb,
                        &mut app.note_cache,
                        &txn,
                        id.bytes(),
                    )
                };
                Thread::unsubscribe_locally(
                    &txn,
                    &app.ndb,
                    &mut app.note_cache,
                    &mut app.threads,
                    &mut app.pool,
                    root_id,
                );
            }

            if let Some(Route::Timeline(TimelineRoute::Profile(pubkey))) = r {
                Profile::unsubscribe_locally(
                    &txn,
                    &app.ndb,
                    &mut app.note_cache,
                    &mut app.profiles,
                    &mut app.pool,
                    pubkey.bytes(),
                );
            }
            col_changed = true;
        } else if let Some(NavAction::Navigated) = self.response.action {
            let cur_router = app.columns_mut().column_mut(col).router_mut();
            cur_router.navigating = false;
            if cur_router.is_replacing() {
                cur_router.remove_previous_routes();
            }
            col_changed = true;
        }

        if let Some(title_response) = &self.response.title_response {
            match title_response {
                TitleResponse::RemoveColumn => {
                    let tl = app.columns().find_timeline_for_column_index(col);
                    if let Some(timeline) = tl {
                        unsubscribe_timeline(app.ndb(), timeline);
                    }

                    app.columns_mut().delete_column(col);
                    col_changed = true;
                }
            }
        }

        if col_changed {
            storage::save_columns(&app.path, app.columns().as_serializable_columns());
        }
    }
}

#[must_use = "RenderNavResponse must be handled by calling .process_render_nav_response(..)"]
pub fn render_nav(col: usize, app: &mut Damus, ui: &mut egui::Ui) -> RenderNavResponse {
    let col_id = app.columns.get_column_id_at_index(col);
    // TODO(jb55): clean up this router_mut mess by using Router<R> in egui-nav directly
    let routes = app
        .columns()
        .column(col)
        .router()
        .routes()
        .iter()
        .map(|r| r.get_titled_route(&app.columns, &app.ndb))
        .collect();

    let nav_response = Nav::new(routes)
        .navigating(app.columns_mut().column_mut(col).router_mut().navigating)
        .returning(app.columns_mut().column_mut(col).router_mut().returning)
        .id_source(egui::Id::new(col_id))
        .title(48.0, title_bar)
        .show_mut(ui, |ui, nav| match &nav.top().route {
            Route::Timeline(tlr) => render_timeline_route(
                &app.ndb,
                &mut app.columns,
                &mut app.drafts,
                &mut app.img_cache,
                &mut app.unknown_ids,
                &mut app.note_cache,
                &mut app.threads,
                &mut app.profiles,
                &mut app.accounts,
                *tlr,
                col,
                app.textmode,
                ui,
            ),
            Route::Accounts(amr) => {
                let action = render_accounts_route(
                    ui,
                    &app.ndb,
                    col,
                    &mut app.columns,
                    &mut app.img_cache,
                    &mut app.accounts,
                    &mut app.view_state.login,
                    *amr,
                );
                let txn = Transaction::new(&app.ndb).expect("txn");
                action.process_action(&mut app.unknown_ids, &app.ndb, &txn);
                None
            }
            Route::Relays => {
                let manager = RelayPoolManager::new(app.pool_mut());
                RelayView::new(manager).ui(ui);
                None
            }
            Route::ComposeNote => {
                let kp = app.accounts.selected_or_first_nsec()?;
                let draft = app.drafts.compose_mut();

                let txn = nostrdb::Transaction::new(&app.ndb).expect("txn");
                let post_response = ui::PostView::new(
                    &app.ndb,
                    draft,
                    PostType::New,
                    &mut app.img_cache,
                    &mut app.note_cache,
                    kp,
                )
                .ui(&txn, ui);

                post_response.action.map(Into::into)
            }
            Route::AddColumn(route) => {
                render_add_column_routes(ui, app, col, route);

                None
            }

            Route::Support => {
                SupportView::new(&mut app.support).show(ui);
                None
            }
        });

    RenderNavResponse::new(col, nav_response)
}

fn unsubscribe_timeline(ndb: &Ndb, timeline: &Timeline) {
    if let Some(sub_id) = timeline.subscription {
        if let Err(e) = ndb.unsubscribe(sub_id) {
            error!("unsubscribe error: {}", e);
        } else {
            info!(
                "successfully unsubscribed from timeline {} with sub id {}",
                timeline.id,
                sub_id.id()
            );
        }
    }
}

fn title_bar(
    ui: &mut egui::Ui,
    allocated_response: egui::Response,
    title_name: String,
    back_name: Option<String>,
) -> egui::InnerResponse<TitleBarResponse<TitleResponse>> {
    let icon_width = 32.0;
    let padding_external = 16.0;
    let padding_internal = 8.0;
    let has_back = back_name.is_some();

    let (spacing_rect, titlebar_rect) = allocated_response
        .rect
        .split_left_right_at_x(allocated_response.rect.left() + padding_external);
    ui.advance_cursor_after_rect(spacing_rect);

    let (titlebar_resp, maybe_button_resp) = if has_back {
        let (button_rect, titlebar_rect) = titlebar_rect
            .split_left_right_at_x(allocated_response.rect.left() + icon_width + padding_external);
        (
            allocated_response.with_new_rect(titlebar_rect),
            Some(back_button(ui, button_rect)),
        )
    } else {
        (allocated_response, None)
    };

    title(
        ui,
        title_name,
        titlebar_resp.rect,
        icon_width,
        if has_back {
            padding_internal
        } else {
            padding_external
        },
    );

    let delete_button_resp = delete_column_button(ui, titlebar_resp, icon_width, padding_external);
    let title_response = if delete_button_resp.clicked() {
        Some(TitleResponse::RemoveColumn)
    } else {
        None
    };

    let titlebar_resp = TitleBarResponse {
        title_response,
        go_back: maybe_button_resp.map_or(false, |r| r.clicked()),
    };

    InnerResponse::new(titlebar_resp, delete_button_resp)
}

fn back_button(ui: &mut egui::Ui, button_rect: egui::Rect) -> egui::Response {
    let horizontal_length = 10.0;
    let arrow_length = 5.0;

    let helper = AnimationHelper::new_from_rect(ui, "note-compose-button", button_rect);
    let painter = ui.painter_at(helper.get_animation_rect());
    let stroke = Stroke::new(1.5, ui.visuals().text_color());

    // Horizontal segment
    let left_horizontal_point = pos2(-horizontal_length / 2., 0.);
    let right_horizontal_point = pos2(horizontal_length / 2., 0.);
    let scaled_left_horizontal_point = helper.scale_pos_from_center(left_horizontal_point);
    let scaled_right_horizontal_point = helper.scale_pos_from_center(right_horizontal_point);

    painter.line_segment(
        [scaled_left_horizontal_point, scaled_right_horizontal_point],
        stroke,
    );

    // Top Arrow
    let sqrt_2_over_2 = std::f32::consts::SQRT_2 / 2.;
    let right_top_arrow_point = helper.scale_pos_from_center(pos2(
        left_horizontal_point.x + (sqrt_2_over_2 * arrow_length),
        right_horizontal_point.y + sqrt_2_over_2 * arrow_length,
    ));

    let scaled_left_arrow_point = scaled_left_horizontal_point;
    painter.line_segment([scaled_left_arrow_point, right_top_arrow_point], stroke);

    let right_bottom_arrow_point = helper.scale_pos_from_center(pos2(
        left_horizontal_point.x + (sqrt_2_over_2 * arrow_length),
        right_horizontal_point.y - sqrt_2_over_2 * arrow_length,
    ));

    painter.line_segment([scaled_left_arrow_point, right_bottom_arrow_point], stroke);

    helper.take_animation_response()
}

fn delete_column_button(
    ui: &mut egui::Ui,
    allocation_response: egui::Response,
    icon_width: f32,
    padding: f32,
) -> egui::Response {
    let img_size = 16.0;
    let max_size = icon_width * ICON_EXPANSION_MULTIPLE;

    let img_data = egui::include_image!("../assets/icons/column_delete_icon_4x.png");
    let img = egui::Image::new(img_data).max_width(img_size);

    let button_rect = {
        let titlebar_rect = allocation_response.rect;
        let titlebar_width = titlebar_rect.width();
        let titlebar_center = titlebar_rect.center();
        let button_center_y = titlebar_center.y;
        let button_center_x =
            titlebar_center.x + (titlebar_width / 2.0) - (max_size / 2.0) - padding;
        egui::Rect::from_center_size(
            pos2(button_center_x, button_center_y),
            egui::vec2(max_size, max_size),
        )
    };

    let helper = AnimationHelper::new_from_rect(ui, "delete-column-button", button_rect);

    let cur_img_size = helper.scale_1d_pos(img_size);

    let animation_rect = helper.get_animation_rect();
    let animation_resp = helper.take_animation_response();
    if allocation_response.union(animation_resp.clone()).hovered() {
        img.paint_at(ui, animation_rect.shrink((max_size - cur_img_size) / 2.0));
    }

    animation_resp
}

fn title(
    ui: &mut egui::Ui,
    title_name: String,
    titlebar_rect: egui::Rect,
    icon_width: f32,
    padding: f32,
) {
    let painter = ui.painter_at(titlebar_rect);

    let font = egui::FontId::new(
        get_font_size(ui.ctx(), &NotedeckTextStyle::Body),
        egui::FontFamily::Name(NamedFontFamily::Bold.as_str().into()),
    );

    let max_title_width = titlebar_rect.width() - icon_width - padding * 2.;
    let title_galley =
        ui.fonts(|f| f.layout(title_name, font, ui.visuals().text_color(), max_title_width));

    let pos = {
        let titlebar_center = titlebar_rect.center();
        let text_height = title_galley.rect.height();

        let galley_pos_x = titlebar_rect.left() + padding;
        let galley_pos_y = titlebar_center.y - (text_height / 2.);
        pos2(galley_pos_x, galley_pos_y)
    };

    painter.galley(pos, title_galley, Color32::WHITE);
}

enum TitleResponse {
    RemoveColumn,
}