core-s3 0.3.1

use embedded_graphics::{Pixel, pixelcolor::Rgb565, prelude::*, primitives::Rectangle};
use embedded_hal::{
    delay::DelayNs,
    digital::{Error as DigitalError, OutputPin},
    spi::{Error as SpiErrorTrait, SpiDevice},
};

const COLOR_STREAM_PIXELS: usize = 128;
const PIXEL_STREAM_PIXELS: usize = 128;
const DRAW_ITER_PIXELS: usize = 64;

const CMD_SOFTWARE_RESET: u8 = 0x01;
const CMD_SLEEP_OUT: u8 = 0x11;
const CMD_DISPLAY_INVERSION_ON: u8 = 0x21;
const CMD_DISPLAY_ON: u8 = 0x29;
const CMD_IDLE_MODE_OFF: u8 = 0x38;
const CMD_COLUMN_ADDRESS_SET: u8 = 0x2A;
const CMD_ROW_ADDRESS_SET: u8 = 0x2B;
const CMD_MEMORY_WRITE: u8 = 0x2C;
const CMD_MEMORY_ACCESS_CONTROL: u8 = 0x36;
const CMD_PIXEL_FORMAT_SET: u8 = 0x3A;
const PIXEL_FORMAT_RGB565: u8 = 0x55;

const SOFTWARE_RESET_DELAY_NS: u32 = 150_000_000;
const SLEEP_OUT_DELAY_NS: u32 = 120_000_000;
const DISPLAY_ON_DELAY_NS: u32 = 20_000_000;

#[cfg_attr(feature = "defmt", derive(defmt::Format))]
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum DisplayError<SpiError, PinError> {
    Spi(SpiError),
    Pin(PinError),
    Text,
}

#[cfg_attr(feature = "defmt", derive(defmt::Format))]
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum DisplayOrientation {
    Portrait,
    PortraitInverted,
    Landscape,
    LandscapeInverted,
}

#[cfg_attr(feature = "defmt", derive(defmt::Format))]
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub struct DisplayGeometry {
    pub width: u16,
    pub height: u16,
    pub offset_x: u16,
    pub offset_y: u16,
}

#[cfg_attr(feature = "defmt", derive(defmt::Format))]
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub struct PanelConfig {
    pub geometry: DisplayGeometry,
    pub invert_colors: bool,
}

#[cfg_attr(feature = "defmt", derive(defmt::Format))]
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub struct BusConfig {
    pub write_hz: u32,
}

pub struct Display<SPI, DC, SDCS> {
    spi: SPI,
    dc: DC,
    sd_cs_guard: SDCS,
    bus: BusConfig,
    panel: PanelConfig,
    orientation: DisplayOrientation,
}

#[derive(Clone, Copy, Debug, Eq, PartialEq)]
struct PixelRun {
    y: i32,
    x_start: i32,
    x_end: i32,
    color: Rgb565,
}

impl PixelRun {
    const fn new(point: Point, color: Rgb565) -> Self {
        Self {
            y: point.y,
            x_start: point.x,
            x_end: point.x,
            color,
        }
    }

    fn try_extend(&mut self, point: Point, color: Rgb565) -> bool {
        if self.y == point.y && self.x_end.saturating_add(1) == point.x && self.color == color {
            self.x_end = point.x;
            true
        } else {
            false
        }
    }

    fn rectangle(self) -> Rectangle {
        Rectangle::new(
            Point::new(self.x_start, self.y),
            Size::new((self.x_end - self.x_start + 1) as u32, 1),
        )
    }
}

struct PixelRowBuffer {
    start: Point,
    colors: [Rgb565; DRAW_ITER_PIXELS],
    len: usize,
}

impl PixelRowBuffer {
    fn new(point: Point, color: Rgb565) -> Self {
        let mut colors = [Rgb565::BLACK; DRAW_ITER_PIXELS];
        colors[0] = color;
        Self {
            start: point,
            colors,
            len: 1,
        }
    }

    fn try_push(&mut self, point: Point, color: Rgb565) -> bool {
        if self.len == DRAW_ITER_PIXELS
            || point.y != self.start.y
            || point.x != self.start.x.saturating_add(self.len as i32)
        {
            return false;
        }
        self.colors[self.len] = color;
        self.len += 1;
        true
    }

    fn area(&self) -> Rectangle {
        Rectangle::new(self.start, Size::new(self.len as u32, 1))
    }

    fn colors(&self) -> &[Rgb565] {
        &self.colors[..self.len]
    }
}

impl<SPI, DC, SDCS> Display<SPI, DC, SDCS> {
    #[must_use]
    pub const fn new(
        spi: SPI,
        dc: DC,
        sd_cs_guard: SDCS,
        bus: BusConfig,
        panel: PanelConfig,
    ) -> Self {
        Self {
            spi,
            dc,
            sd_cs_guard,
            bus,
            panel,
            orientation: DisplayOrientation::Landscape,
        }
    }

    #[must_use]
    pub const fn bus_config(&self) -> BusConfig {
        self.bus
    }

    #[must_use]
    pub const fn panel_config(&self) -> PanelConfig {
        self.panel
    }

    #[must_use]
    pub const fn geometry(&self) -> DisplayGeometry {
        self.panel.geometry
    }

    #[must_use]
    pub const fn orientation(&self) -> DisplayOrientation {
        self.orientation
    }

    pub fn set_orientation(&mut self, orientation: DisplayOrientation) {
        self.orientation = orientation;
    }

    pub fn clip_rectangle(&self, area: Rectangle) -> Rectangle {
        area.intersection(&self.bounding_box())
    }

    pub fn map_logical_rectangle_to_native(&self, area: &Rectangle) -> Rectangle {
        self.map_rectangle_to_native(area)
    }

    pub fn release(self) -> (SPI, DC, SDCS) {
        (self.spi, self.dc, self.sd_cs_guard)
    }

    fn logical_size(&self) -> Size {
        let geometry = self.panel.geometry;
        match self.orientation {
            DisplayOrientation::Portrait | DisplayOrientation::PortraitInverted => {
                Size::new(u32::from(geometry.height), u32::from(geometry.width))
            }
            DisplayOrientation::Landscape | DisplayOrientation::LandscapeInverted => {
                Size::new(u32::from(geometry.width), u32::from(geometry.height))
            }
        }
    }

    fn map_rectangle_to_native(&self, area: &Rectangle) -> Rectangle {
        let geometry = self.panel.geometry;
        let native_width = i32::from(geometry.width);
        let native_height = i32::from(geometry.height);
        let x = area.top_left.x;
        let y = area.top_left.y;
        let width = area.size.width as i32;
        let height = area.size.height as i32;

        match self.orientation {
            DisplayOrientation::Landscape => *area,
            DisplayOrientation::LandscapeInverted => Rectangle::new(
                Point::new(native_width - x - width, native_height - y - height),
                area.size,
            ),
            DisplayOrientation::Portrait => Rectangle::new(
                Point::new(y, native_height - x - width),
                Size::new(area.size.height, area.size.width),
            ),
            DisplayOrientation::PortraitInverted => Rectangle::new(
                Point::new(native_width - y - height, x),
                Size::new(area.size.height, area.size.width),
            ),
        }
    }
}

impl<SPI, DC, SDCS, SpiError, PinError> Display<SPI, DC, SDCS>
where
    SPI: SpiDevice<Error = SpiError>,
    DC: OutputPin<Error = PinError>,
    SDCS: OutputPin<Error = PinError>,
    SpiError: SpiErrorTrait,
    PinError: DigitalError,
{
    pub fn init(
        &mut self,
        delay: &mut impl DelayNs,
    ) -> Result<(), DisplayError<SpiError, PinError>> {
        self.sd_cs_guard.set_high().map_err(DisplayError::Pin)?;
        self.command(CMD_SOFTWARE_RESET, &[])?;
        delay.delay_ns(SOFTWARE_RESET_DELAY_NS);
        self.init_ili9342_registers()?;
        self.command(CMD_SLEEP_OUT, &[])?;
        delay.delay_ns(SLEEP_OUT_DELAY_NS);
        self.command(CMD_PIXEL_FORMAT_SET, &[PIXEL_FORMAT_RGB565])?;
        self.write_orientation()?;
        if self.panel.invert_colors {
            self.command(CMD_DISPLAY_INVERSION_ON, &[])?;
        }
        self.command(CMD_IDLE_MODE_OFF, &[])?;
        self.command(CMD_DISPLAY_ON, &[])?;
        delay.delay_ns(DISPLAY_ON_DELAY_NS);
        Ok(())
    }

    fn init_ili9342_registers(&mut self) -> Result<(), DisplayError<SpiError, PinError>> {
        self.command(0xC8, &[0xFF, 0x93, 0x42])?;
        self.command(0xC0, &[0x12, 0x12])?;
        self.command(0xC1, &[0x03])?;
        self.command(0xC5, &[0xF2])?;
        self.command(0xB0, &[0xE0])?;
        self.command(0xF6, &[0x01, 0x00, 0x00])?;
        self.command(
            0xE0,
            &[
                0x00, 0x0C, 0x11, 0x04, 0x11, 0x08, 0x37, 0x89, 0x4C, 0x06, 0x0C, 0x0A, 0x2E, 0x34,
                0x0F,
            ],
        )?;
        self.command(
            0xE1,
            &[
                0x00, 0x0B, 0x11, 0x05, 0x13, 0x09, 0x33, 0x67, 0x48, 0x07, 0x0E, 0x0B, 0x2E, 0x33,
                0x0F,
            ],
        )?;
        self.command(0xB6, &[0x08, 0x82, 0x1D, 0x04])
    }

    pub fn set_orientation_and_apply(
        &mut self,
        orientation: DisplayOrientation,
    ) -> Result<(), DisplayError<SpiError, PinError>> {
        self.orientation = orientation;
        self.write_orientation()
    }

    fn write_orientation(&mut self) -> Result<(), DisplayError<SpiError, PinError>> {
        self.command(
            CMD_MEMORY_ACCESS_CONTROL,
            &[madctl_for_orientation(self.orientation)],
        )
    }

    pub fn command(
        &mut self,
        command: u8,
        data: &[u8],
    ) -> Result<(), DisplayError<SpiError, PinError>> {
        self.dc.set_low().map_err(DisplayError::Pin)?;
        self.spi.write(&[command]).map_err(DisplayError::Spi)?;
        if !data.is_empty() {
            self.dc.set_high().map_err(DisplayError::Pin)?;
            self.spi.write(data).map_err(DisplayError::Spi)?;
        }
        Ok(())
    }

    pub fn clear(&mut self, color: Rgb565) -> Result<(), DisplayError<SpiError, PinError>> {
        self.fill_solid(&Rectangle::new(Point::zero(), self.logical_size()), color)
    }

    pub fn blit_pixels<I>(
        &mut self,
        area: &Rectangle,
        pixels: I,
    ) -> Result<(), DisplayError<SpiError, PinError>>
    where
        I: IntoIterator<Item = Rgb565>,
    {
        let clipped = area.intersection(&self.bounding_box());
        if clipped.is_zero_sized() {
            return Ok(());
        }
        if self.orientation == DisplayOrientation::Landscape && clipped == *area {
            self.set_address_window(&clipped)?;
            self.write_color_stream(
                pixels,
                clipped.size.width.saturating_mul(clipped.size.height) as usize,
            )
        } else {
            self.fill_contiguous(area, pixels)
        }
    }

    fn flush_run(&mut self, run: PixelRun) -> Result<(), DisplayError<SpiError, PinError>> {
        self.fill_solid(&run.rectangle(), run.color)
    }

    fn flush_pixel_row(
        &mut self,
        row: &PixelRowBuffer,
    ) -> Result<(), DisplayError<SpiError, PinError>> {
        self.blit_pixels(&row.area(), row.colors().iter().copied())
    }

    fn set_address_window(
        &mut self,
        area: &Rectangle,
    ) -> Result<(), DisplayError<SpiError, PinError>> {
        let geometry = self.panel.geometry;
        let x0 = geometry.offset_x + area.top_left.x.max(0) as u16;
        let y0 = geometry.offset_y + area.top_left.y.max(0) as u16;
        let x1 = x0 + area.size.width.saturating_sub(1) as u16;
        let y1 = y0 + area.size.height.saturating_sub(1) as u16;
        self.command(
            CMD_COLUMN_ADDRESS_SET,
            &[(x0 >> 8) as u8, x0 as u8, (x1 >> 8) as u8, x1 as u8],
        )?;
        self.command(
            CMD_ROW_ADDRESS_SET,
            &[(y0 >> 8) as u8, y0 as u8, (y1 >> 8) as u8, y1 as u8],
        )?;
        self.dc.set_low().map_err(DisplayError::Pin)?;
        self.spi
            .write(&[CMD_MEMORY_WRITE])
            .map_err(DisplayError::Spi)?;
        self.dc.set_high().map_err(DisplayError::Pin)
    }

    fn write_repeated_color(
        &mut self,
        color: Rgb565,
        pixels: usize,
    ) -> Result<(), DisplayError<SpiError, PinError>> {
        let raw = color.into_storage().to_be_bytes();
        let mut chunk = [0u8; COLOR_STREAM_PIXELS * 2];
        for pixel in chunk.chunks_exact_mut(2) {
            pixel.copy_from_slice(&raw);
        }
        let mut remaining = pixels;
        while remaining > 0 {
            let write_pixels = remaining.min(COLOR_STREAM_PIXELS);
            let write_len = write_pixels * 2;
            self.spi
                .write(&chunk[..write_len])
                .map_err(DisplayError::Spi)?;
            remaining -= write_pixels;
        }
        Ok(())
    }

    fn write_color_stream<I>(
        &mut self,
        pixels: I,
        max_pixels: usize,
    ) -> Result<(), DisplayError<SpiError, PinError>>
    where
        I: IntoIterator<Item = Rgb565>,
    {
        let mut chunk = [0u8; PIXEL_STREAM_PIXELS * 2];
        let mut buffered_pixels = 0usize;

        for (written_pixels, color) in pixels.into_iter().enumerate() {
            if written_pixels >= max_pixels {
                break;
            }
            let raw = color.into_storage().to_be_bytes();
            let offset = buffered_pixels * 2;
            chunk[offset] = raw[0];
            chunk[offset + 1] = raw[1];
            buffered_pixels += 1;

            if buffered_pixels == PIXEL_STREAM_PIXELS {
                self.spi.write(&chunk).map_err(DisplayError::Spi)?;
                buffered_pixels = 0;
            }
        }

        if buffered_pixels > 0 {
            self.spi
                .write(&chunk[..buffered_pixels * 2])
                .map_err(DisplayError::Spi)?;
        }
        Ok(())
    }
}

impl<SPI, DC, SDCS, SpiError, PinError> DrawTarget for Display<SPI, DC, SDCS>
where
    SPI: SpiDevice<Error = SpiError>,
    DC: OutputPin<Error = PinError>,
    SDCS: OutputPin<Error = PinError>,
    SpiError: SpiErrorTrait,
    PinError: DigitalError,
{
    type Color = Rgb565;
    type Error = DisplayError<SpiError, PinError>;

    fn draw_iter<I>(&mut self, pixels: I) -> Result<(), Self::Error>
    where
        I: IntoIterator<Item = Pixel<Self::Color>>,
    {
        let mut row = None;
        for Pixel(point, color) in pixels {
            if !self.bounding_box().contains(point) {
                if let Some(current) = row.take() {
                    self.flush_pixel_row(&current)?;
                }
                continue;
            }
            if let Some(mut current) = row.take() {
                if current.try_push(point, color) {
                    row = Some(current);
                } else {
                    self.flush_pixel_row(&current)?;
                    row = Some(PixelRowBuffer::new(point, color));
                }
            } else {
                row = Some(PixelRowBuffer::new(point, color));
            }
        }
        if let Some(current) = row {
            self.flush_pixel_row(&current)?;
        }
        Ok(())
    }

    fn fill_solid(&mut self, area: &Rectangle, color: Self::Color) -> Result<(), Self::Error> {
        let clipped = area.intersection(&self.bounding_box());
        if clipped.is_zero_sized() {
            return Ok(());
        }
        let native = self.map_rectangle_to_native(&clipped);
        self.set_address_window(&native)?;
        self.write_repeated_color(
            color,
            clipped.size.width.saturating_mul(clipped.size.height) as usize,
        )
    }

    fn fill_contiguous<I>(&mut self, area: &Rectangle, colors: I) -> Result<(), Self::Error>
    where
        I: IntoIterator<Item = Self::Color>,
    {
        let clipped = area.intersection(&self.bounding_box());
        if clipped.is_zero_sized() {
            return Ok(());
        }
        if self.orientation == DisplayOrientation::Landscape && clipped == *area {
            self.set_address_window(&clipped)?;
            return self.write_color_stream(
                colors,
                clipped.size.width.saturating_mul(clipped.size.height) as usize,
            );
        }

        let area_width = area.size.width as i32;
        let mut run = None;
        for (index, color) in colors.into_iter().enumerate() {
            let index = index as i32;
            let point = Point::new(
                area.top_left.x + index % area_width,
                area.top_left.y + index / area_width,
            );
            if !clipped.contains(point) {
                if let Some(current) = run.take() {
                    self.flush_run(current)?;
                }
                continue;
            }
            if let Some(mut current) = run.take() {
                if current.try_extend(point, color) {
                    run = Some(current);
                } else {
                    self.flush_run(current)?;
                    run = Some(PixelRun::new(point, color));
                }
            } else {
                run = Some(PixelRun::new(point, color));
            }
        }
        if let Some(current) = run {
            self.flush_run(current)?;
        }
        Ok(())
    }
}

const fn madctl_for_orientation(orientation: DisplayOrientation) -> u8 {
    match orientation {
        DisplayOrientation::Landscape => 0x08,
        DisplayOrientation::LandscapeInverted => 0xC8,
        DisplayOrientation::Portrait => 0x68,
        DisplayOrientation::PortraitInverted => 0xA8,
    }
}

impl<SPI, DC, SDCS> OriginDimensions for Display<SPI, DC, SDCS> {
    fn size(&self) -> Size {
        self.logical_size()
    }
}