use crate::app::App;
use crate::common::CommonState;
use crate::edit::{apply_map_edits, check_sidewalk_connectivity, TrafficSignalEditor};
use crate::game::{State, Transition};
use crate::render::DrawIntersection;
use crate::sandbox::GameplayMode;
use abstutil::Timer;
use geom::Polygon;
use map_model::{
    ControlStopSign, ControlTrafficSignal, EditCmd, EditIntersection, IntersectionID, RoadID,
};
use maplit::btreeset;
use std::collections::HashMap;
use widgetry::{
    hotkey, Btn, EventCtx, GeomBatch, GfxCtx, HorizontalAlignment, Key, Line, Outcome, Panel, Text,
    VerticalAlignment, Widget,
};

// TODO For now, individual turns can't be manipulated. Banning turns could be useful, but I'm not
// sure what to do about the player orphaning a section of the map.
pub struct StopSignEditor {
    panel: Panel,
    id: IntersectionID,
    mode: GameplayMode,
    // (octagon, pole)
    geom: HashMap<RoadID, (Polygon, Polygon)>,
    selected_sign: Option<RoadID>,
}

impl StopSignEditor {
    pub fn new(
        ctx: &mut EventCtx,
        app: &mut App,
        id: IntersectionID,
        mode: GameplayMode,
    ) -> Box<dyn State> {
        app.primary.current_selection = None;
        let geom = app
            .primary
            .map
            .get_stop_sign(id)
            .roads
            .iter()
            .map(|(r, ss)| {
                let (octagon, pole) =
                    DrawIntersection::stop_sign_geom(ss, &app.primary.map).unwrap();
                (*r, (octagon, pole))
            })
            .collect();

        let panel = Panel::new(Widget::col(vec![
            Line("Stop sign editor").small_heading().draw(ctx),
            if ControlStopSign::new(&app.primary.map, id)
                != app.primary.map.get_stop_sign(id).clone()
            {
                Btn::text_fg("reset to default").build_def(ctx, hotkey(Key::R))
            } else {
                Btn::text_fg("reset to default").inactive(ctx)
            },
            Btn::text_fg("close intersection for construction").build_def(ctx, hotkey(Key::C)),
            Btn::text_fg("convert to traffic signal").build_def(ctx, None),
            Btn::text_fg("Finish").build_def(ctx, hotkey(Key::Escape)),
        ]))
        .aligned(HorizontalAlignment::Center, VerticalAlignment::Top)
        .build(ctx);

        Box::new(StopSignEditor {
            panel,
            id,
            mode,
            geom,
            selected_sign: None,
        })
    }
}

impl State for StopSignEditor {
    fn event(&mut self, ctx: &mut EventCtx, app: &mut App) -> Transition {
        ctx.canvas_movement();

        if ctx.redo_mouseover() {
            self.selected_sign = None;
            if let Some(pt) = ctx.canvas.get_cursor_in_map_space() {
                for (r, (octagon, _)) in &self.geom {
                    if octagon.contains_pt(pt) {
                        self.selected_sign = Some(*r);
                        break;
                    }
                }
            }
        }

        if let Some(r) = self.selected_sign {
            let mut sign = app.primary.map.get_stop_sign(self.id).clone();
            let label = if sign.roads[&r].must_stop {
                "remove stop sign"
            } else {
                "add stop sign"
            };
            if app.per_obj.left_click(ctx, label) {
                sign.flip_sign(r);

                let mut edits = app.primary.map.get_edits().clone();
                edits.commands.push(EditCmd::ChangeIntersection {
                    i: self.id,
                    old: app.primary.map.get_i_edit(self.id),
                    new: EditIntersection::StopSign(sign),
                });
                apply_map_edits(ctx, app, edits);
                return Transition::Replace(StopSignEditor::new(
                    ctx,
                    app,
                    self.id,
                    self.mode.clone(),
                ));
            }
        }

        match self.panel.event(ctx) {
            Outcome::Clicked(x) => match x.as_ref() {
                "Finish" => {
                    return Transition::Pop;
                }
                "reset to default" => {
                    let mut edits = app.primary.map.get_edits().clone();
                    edits.commands.push(EditCmd::ChangeIntersection {
                        i: self.id,
                        old: app.primary.map.get_i_edit(self.id),
                        new: EditIntersection::StopSign(ControlStopSign::new(
                            &app.primary.map,
                            self.id,
                        )),
                    });
                    apply_map_edits(ctx, app, edits);
                    return Transition::Replace(StopSignEditor::new(
                        ctx,
                        app,
                        self.id,
                        self.mode.clone(),
                    ));
                }
                "close intersection for construction" => {
                    let cmd = EditCmd::ChangeIntersection {
                        i: self.id,
                        old: app.primary.map.get_i_edit(self.id),
                        new: EditIntersection::Closed,
                    };
                    if let Some(err) = check_sidewalk_connectivity(ctx, app, cmd.clone()) {
                        return Transition::Push(err);
                    } else {
                        let mut edits = app.primary.map.get_edits().clone();
                        edits.commands.push(cmd);
                        apply_map_edits(ctx, app, edits);

                        return Transition::Pop;
                    }
                }
                "convert to traffic signal" => {
                    let mut edits = app.primary.map.get_edits().clone();
                    edits.commands.push(EditCmd::ChangeIntersection {
                        i: self.id,
                        old: app.primary.map.get_i_edit(self.id),
                        new: EditIntersection::TrafficSignal(
                            ControlTrafficSignal::new(
                                &app.primary.map,
                                self.id,
                                &mut Timer::throwaway(),
                            )
                            .export(&app.primary.map),
                        ),
                    });
                    apply_map_edits(ctx, app, edits);
                    app.primary
                        .sim
                        .handle_live_edited_traffic_signals(&app.primary.map);
                    return Transition::Replace(TrafficSignalEditor::new(
                        ctx,
                        app,
                        btreeset! {self.id},
                        self.mode.clone(),
                    ));
                }
                _ => unreachable!(),
            },
            _ => {}
        }
        Transition::Keep
    }

    fn draw(&self, g: &mut GfxCtx, app: &App) {
        let map = &app.primary.map;
        let sign = map.get_stop_sign(self.id);

        let mut batch = GeomBatch::new();

        for (r, (octagon, pole)) in &self.geom {
            // The intersection will already draw enabled stop signs
            if Some(*r) == self.selected_sign {
                batch.push(app.cs.perma_selected_object, octagon.clone());
                if !sign.roads[r].must_stop {
                    batch.push(app.cs.stop_sign_pole.alpha(0.6), pole.clone());
                }
            } else if !sign.roads[r].must_stop {
                batch.push(app.cs.stop_sign.alpha(0.6), octagon.clone());
                batch.push(app.cs.stop_sign_pole.alpha(0.6), pole.clone());
            }
        }

        batch.draw(g);

        self.panel.draw(g);
        if let Some(r) = self.selected_sign {
            let mut osd = Text::new();
            osd.add_appended(vec![
                Line("Stop sign for "),
                Line(
                    app.primary
                        .map
                        .get_r(r)
                        .get_name(app.opts.language.as_ref()),
                )
                .fg(app.cs.bottom_bar_name),
            ]);
            CommonState::draw_custom_osd(g, app, osd);
        } else {
            CommonState::draw_osd(g, app);
        }
    }
}