use api::*;
use canary_script::*;

use canary_music_player::{AlbumInfo, TrackInfo};

use crate::widgets::prelude::*;
use dialog::{DialogBodyStyle, DialogFooterStyle};
use shell::Offset;
use text::{HorizontalAlignment, Label, LabelText};

pub struct MusicPlayerPanel {
    panel: Panel,
    widget: Option<MusicPlayerWidget>,
    disconnected: Offset<Label>,
}

impl BindPanel for MusicPlayerPanel {
    fn bind(panel: Panel, _msg: Message) -> Box<dyn PanelImpl> {
        let dc_text = LabelText {
            font: Font::new(crate::DISPLAY_FONT),
            text: "Disconnected".to_string(),
        };

        let disconnected = Label::new_centered(dc_text, 10.0, Color::WHITE);
        let disconnected = Offset::new(disconnected, Vec2::ZERO);

        Box::new(Self {
            panel,
            widget: None,
            disconnected,
        })
    }
}

impl PanelImpl for MusicPlayerPanel {
    fn update(&mut self, dt: f32) {
        if let Some(widget) = self.widget.as_mut() {
            Widget::update(widget, dt);
        }
    }

    fn draw(&mut self) {
        let ctx = DrawContext::new(self.panel);

        if let Some(widget) = self.widget.as_mut() {
            Widget::draw(widget, &ctx);
        } else {
            self.disconnected.draw(&ctx);
        }
    }

    fn on_resize(&mut self, new_size: Vec2) {
        self.disconnected.set_offset(new_size / 2.0);

        if let Some(widget) = self.widget.as_mut() {
            widget.resize(new_size);
        }
    }

    fn on_cursor_event(&mut self, kind: CursorEventKind, at: Vec2) {
        if let Some(widget) = self.widget.as_mut() {
            Widget::on_cursor_event(widget, kind, at);
        }
    }

    fn on_message(&mut self, msg: Message) {
        use canary_music_player::{serde_json::from_slice, InMsg};
        let msg = msg.to_vec();
        let msg: InMsg = match from_slice(&msg) {
            Ok(msg) => msg,
            Err(_) => return,
        };

        use InMsg::*;
        match (self.widget.as_mut(), msg) {
            (Some(_), Disconnected) => self.widget = None,
            (None, Connected) => self.widget = Some(MusicPlayerWidget::new()),
            (Some(widget), AlbumChanged(info)) => widget.update_album(info),
            (Some(widget), TrackChanged(info)) => widget.update_track(info),
            _ => {}
        }
    }
}

pub struct MusicPlayerStyle {
    pub body: DialogBodyStyle,
    pub footer: DialogFooterStyle,
    pub rounding: f32,
    pub art_margin: f32,
}

impl Default for MusicPlayerStyle {
    fn default() -> Self {
        Self {
            body: Default::default(),
            footer: Default::default(),
            rounding: 5.0,
            art_margin: 5.0,
        }
    }
}

pub struct MusicPlayerWidget {
    artist: Offset<Label>,
    album: Offset<Label>,
    track: Offset<Label>,
    style: MusicPlayerStyle,
    art_rect: Rect,
    body_rect: Rect,
    footer_rect: Rect,
}

impl Container for MusicPlayerWidget {
    fn with_children(&mut self, mut f: impl FnMut(&mut dyn Widget)) {
        f(&mut self.artist);
        f(&mut self.album);
        f(&mut self.track);
    }

    fn draw(&mut self, ctx: &DrawContext) {
        ctx.draw_partially_rounded_rect(
            CornerFlags::TOP,
            self.body_rect,
            self.style.rounding,
            self.style.body.color,
        );

        ctx.draw_rounded_rect(self.art_rect, self.style.rounding, Color::MAGENTA);

        ctx.draw_partially_rounded_rect(
            CornerFlags::BOTTOM,
            self.footer_rect,
            self.style.rounding,
            self.style.footer.color,
        );
    }
}

impl MusicPlayerWidget {
    pub fn new() -> Self {
        let font = Font::new(crate::DISPLAY_FONT);

        let make_label = |content: &str| {
            let text = LabelText {
                font,
                text: content.to_string(),
            };

            let label = Label::new_centered(text, 10.0, Color::BLACK);
            Offset::new(label, Vec2::ZERO)
        };

        Self {
            artist: make_label("Artist"),
            album: make_label("Album"),
            track: make_label("Track"),
            style: Default::default(),
            art_rect: Rect::from_xy_size(Vec2::ZERO, Vec2::ZERO),
            body_rect: Rect::from_xy_size(Vec2::ZERO, Vec2::ZERO),
            footer_rect: Rect::from_xy_size(Vec2::ZERO, Vec2::ZERO),
        }
    }

    pub fn resize(&mut self, new_size: Vec2) {
        let style = &self.style;
        let width = new_size.x;
        let body_height = new_size.y - style.footer.height;
        let body_height = body_height.max(0.0);
        let body_size = Vec2::new(width, body_height);
        let footer_size = Vec2::new(width, style.footer.height);

        let art_size = body_height - style.art_margin * 2.0;
        self.art_rect = Rect::from_xy_size(Vec2::splat(style.art_margin), Vec2::splat(art_size));

        let label_x = (width + self.art_rect.br.x) / 2.0;
        let artist_baseline = body_height * 0.25;
        let album_baseline = body_height * 0.55;
        let track_baseline = body_height * 0.85;

        self.artist.set_offset(Vec2::new(label_x, artist_baseline));
        self.album.set_offset(Vec2::new(label_x, album_baseline));
        self.track.set_offset(Vec2::new(label_x, track_baseline));

        self.body_rect = Rect::from_xy_size(Vec2::ZERO, body_size);
        self.footer_rect = Rect::from_xy_size(self.body_rect.bl(), footer_size);
    }

    pub fn update_album(&mut self, info: AlbumInfo) {
        self.album.set_text(
            info.title
                .as_ref()
                .map(|s| s.as_str())
                .unwrap_or("<album here>"),
        );
    }

    pub fn update_track(&mut self, info: TrackInfo) {
        self.artist.set_text(
            info.artists
                .first()
                .map(|s| s.as_str())
                .unwrap_or("<artist here>"),
        );

        self.track.set_text(
            info.title
                .as_ref()
                .map(|s| s.as_str())
                .unwrap_or("<album here>"),
        );
    }
}