use std::{fmt, mem};
use std::error::Error;
#[cfg(feature = "icon_loading")]
use std::io::{BufRead, Seek};
#[cfg(feature = "icon_loading")]
use std::path::Path;
#[cfg(feature = "icon_loading")]
use image;
#[repr(C)]
#[derive(Debug)]
pub(crate) struct Pixel {
pub(crate) r: u8,
pub(crate) g: u8,
pub(crate) b: u8,
pub(crate) a: u8,
}
pub(crate) const PIXEL_SIZE: usize = mem::size_of::<Pixel>();
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum BadIcon {
ByteCountNotDivisibleBy4 {
byte_count: usize,
},
DimensionsVsPixelCount {
width: u32,
height: u32,
width_x_height: usize,
pixel_count: usize,
},
}
impl fmt::Display for BadIcon {
fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
let msg = match self {
&BadIcon::ByteCountNotDivisibleBy4 { byte_count } => format!(
"The length of the `rgba` argument ({:?}) isn't divisible by 4, making it impossible to interpret as 32bpp RGBA pixels.",
byte_count,
),
&BadIcon::DimensionsVsPixelCount {
width,
height,
width_x_height,
pixel_count,
} => format!(
"The specified dimensions ({:?}x{:?}) don't match the number of pixels supplied by the `rgba` argument ({:?}). For those dimensions, the expected pixel count is {:?}.",
width, height, pixel_count, width_x_height,
),
};
write!(formatter, "{}", msg)
}
}
impl Error for BadIcon {
fn description(&self) -> &str {
"A valid icon cannot be created from these arguments"
}
fn cause(&self) -> Option<&Error> {
Some(self)
}
}
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct Icon {
pub(crate) rgba: Vec<u8>,
pub(crate) width: u32,
pub(crate) height: u32,
}
impl Icon {
pub fn from_rgba(rgba: Vec<u8>, width: u32, height: u32) -> Result<Self, BadIcon> {
if rgba.len() % PIXEL_SIZE != 0 {
return Err(BadIcon::ByteCountNotDivisibleBy4 { byte_count: rgba.len() });
}
let pixel_count = rgba.len() / PIXEL_SIZE;
if pixel_count != (width * height) as usize {
Err(BadIcon::DimensionsVsPixelCount {
width,
height,
width_x_height: (width * height) as usize,
pixel_count,
})
} else {
Ok(Icon { rgba, width, height })
}
}
#[cfg(feature = "icon_loading")]
pub fn from_path<P: AsRef<Path>>(path: P) -> image::ImageResult<Self> {
image::open(path).map(Into::into)
}
#[cfg(feature = "icon_loading")]
pub fn from_reader<R: BufRead + Seek>(
reader: R,
format: image::ImageFormat,
) -> image::ImageResult<Self> {
image::load(reader, format).map(Into::into)
}
#[cfg(feature = "icon_loading")]
pub fn from_bytes(bytes: &[u8]) -> image::ImageResult<Self> {
image::load_from_memory(bytes).map(Into::into)
}
#[cfg(feature = "icon_loading")]
pub fn from_bytes_with_format(
bytes: &[u8],
format: image::ImageFormat,
) -> image::ImageResult<Self> {
image::load_from_memory_with_format(bytes, format).map(Into::into)
}
}
#[cfg(feature = "icon_loading")]
impl From<image::DynamicImage> for Icon {
fn from(image: image::DynamicImage) -> Self {
use image::{GenericImageView, Pixel};
let (width, height) = image.dimensions();
let mut rgba = Vec::with_capacity((width * height) as usize * PIXEL_SIZE);
for (_, _, pixel) in image.pixels() {
rgba.extend_from_slice(&pixel.to_rgba().data);
}
Icon { rgba, width, height }
}
}
#[cfg(feature = "icon_loading")]
impl From<image::RgbaImage> for Icon {
fn from(buf: image::RgbaImage) -> Self {
let (width, height) = buf.dimensions();
let mut rgba = Vec::with_capacity((width * height) as usize * PIXEL_SIZE);
for (_, _, pixel) in buf.enumerate_pixels() {
rgba.extend_from_slice(&pixel.data);
}
Icon { rgba, width, height }
}
}