use super::theme;
use crate::ui::{
    component::{
        base::ComponentExt, label::Label, text::TextStyle, Child, Component, Event, EventCtx,
    },
    display::Icon,
    geometry::{Alignment, Insets, Rect},
    model_mercury::component::{Button, ButtonMsg, CancelInfoConfirmMsg},
    shape::Renderer,
};

const TITLE_HEIGHT: i16 = 42;
const TITLE_SPACE: i16 = 2;

pub struct Frame<T, U> {
    border: Insets,
    title: Child<Label<U>>,
    subtitle: Option<Child<Label<U>>>,
    button: Option<Child<Button<&'static str>>>,
    button_msg: CancelInfoConfirmMsg,
    content: Child<T>,
}

pub enum FrameMsg<T> {
    Content(T),
    Button(CancelInfoConfirmMsg),
}

impl<T, U> Frame<T, U>
where
    T: Component,
    U: AsRef<str>,
{
    pub fn new(alignment: Alignment, title: U, content: T) -> Self {
        let style: TextStyle = theme::label_title_main();
        Self {
            title: Child::new(Label::new(title, alignment, style).vertically_centered()),
            subtitle: None,
            border: theme::borders(),
            button: None,
            button_msg: CancelInfoConfirmMsg::Cancelled,
            content: Child::new(content),
        }
    }

    pub fn left_aligned(title: U, content: T) -> Self {
        Self::new(Alignment::Start, title, content)
    }

    pub fn right_aligned(title: U, content: T) -> Self {
        Self::new(Alignment::End, title, content)
    }

    pub fn centered(title: U, content: T) -> Self {
        Self::new(Alignment::Center, title, content)
    }

    pub fn with_border(mut self, border: Insets) -> Self {
        self.border = border;
        self
    }

    pub fn with_subtitle(mut self, subtitle: U) -> Self {
        let style = theme::label_title_sub();
        self.title = Child::new(self.title.into_inner().top_aligned());
        self.subtitle = Some(Child::new(Label::new(
            subtitle,
            self.title.inner().alignment(),
            style,
        )));
        self
    }

    fn with_button(mut self, icon: Icon, msg: CancelInfoConfirmMsg) -> Self {
        let touch_area = Insets {
            left: self.border.left * 4,
            bottom: self.border.bottom * 4,
            ..self.border
        };
        self.button = Some(Child::new(
            Button::with_icon(icon)
                .with_expanded_touch_area(touch_area)
                .styled(theme::button_moreinfo()),
        ));
        self.button_msg = msg;
        self
    }

    pub fn with_cancel_button(self) -> Self {
        self.with_button(theme::ICON_CORNER_CANCEL, CancelInfoConfirmMsg::Cancelled)
    }

    pub fn with_info_button(self) -> Self {
        self.with_button(theme::ICON_MENU, CancelInfoConfirmMsg::Info)
    }

    pub fn inner(&self) -> &T {
        self.content.inner()
    }

    pub fn update_title(&mut self, ctx: &mut EventCtx, new_title: U) {
        self.title.mutate(ctx, |ctx, t| {
            t.set_text(new_title);
            t.request_complete_repaint(ctx)
        })
    }

    pub fn update_content<F, R>(&mut self, ctx: &mut EventCtx, update_fn: F) -> R
    where
        F: Fn(&mut T) -> R,
    {
        self.content.mutate(ctx, |ctx, c| {
            let res = update_fn(c);
            c.request_complete_repaint(ctx);
            res
        })
    }
}

impl<T, U> Component for Frame<T, U>
where
    T: Component,
    U: AsRef<str>,
{
    type Msg = FrameMsg<T::Msg>;

    fn place(&mut self, bounds: Rect) -> Rect {
        let (mut header_area, content_area) = bounds.split_top(TITLE_HEIGHT);
        let content_area = content_area.inset(Insets::right(TITLE_SPACE));

        if let Some(b) = &mut self.button {
            let (rest, button_area) = header_area.split_right(TITLE_HEIGHT);
            header_area = rest;
            b.place(button_area);
        }

        if self.subtitle.is_some() {
            let title_area = self.title.place(header_area);
            let remaining = header_area.inset(Insets::top(title_area.height()));
            let _subtitle_area = self.subtitle.place(remaining);
        } else {
            self.title.place(header_area);
        }
        self.content.place(content_area);
        bounds
    }

    fn event(&mut self, ctx: &mut EventCtx, event: Event) -> Option<Self::Msg> {
        self.title.event(ctx, event);
        self.subtitle.event(ctx, event);
        if let Some(ButtonMsg::Clicked) = self.button.event(ctx, event) {
            return Some(FrameMsg::Button(self.button_msg));
        }
        self.content.event(ctx, event).map(FrameMsg::Content)
    }

    fn paint(&mut self) {
        self.title.paint();
        self.subtitle.paint();
        self.button.paint();
        self.content.paint();
    }

    fn render<'s>(&'s self, target: &mut impl Renderer<'s>) {
        self.title.render(target);
        self.subtitle.render(target);
        self.button.render(target);
        self.content.render(target);
    }

    #[cfg(feature = "ui_bounds")]
    fn bounds(&self, sink: &mut dyn FnMut(Rect)) {
        self.title.bounds(sink);
        self.subtitle.bounds(sink);
        self.button.bounds(sink);
        self.content.bounds(sink);
    }
}

#[cfg(feature = "ui_debug")]
impl<T, U> crate::trace::Trace for Frame<T, U>
where
    T: crate::trace::Trace,
    U: AsRef<str>,
{
    fn trace(&self, t: &mut dyn crate::trace::Tracer) {
        t.component("Frame");
        t.child("title", &self.title);
        t.child("content", &self.content);
        if let Some(subtitle) = &self.subtitle {
            t.child("subtitle", subtitle);
        }
        if let Some(button) = &self.button {
            t.child("button", button);
        }
    }
}