use crate::common::IResult;
#[cfg(feature = "cover")]
mod text_width {
use ab_glyph::PxScale;
use image::{DynamicImage, GenericImageView, Rgba};
pub struct ImageCrop {
pub original: DynamicImage,
}
impl ImageCrop {
pub fn new(text: &str, width: u32, height: u32, font: &impl ab_glyph::Font) -> ImageCrop {
let mut img = DynamicImage::new_rgb8(width, height);
imageproc::drawing::draw_text_mut(
&mut img,
image::Rgba([255u8, 255u8, 255u8, 1u8]),
0,
0,
PxScale {
x: width as f32,
y: height as f32,
},
font,
text,
);
ImageCrop { original: img }
}
pub fn text_width(&self) -> (u32, u32) {
let (width, height) = self.original.dimensions();
let mut left_x = 0;
let mut right_x = 0;
#[inline]
fn is_not_black(pixel: Rgba<u8>) -> bool {
pixel[0] != 0 && pixel[1] != 0 && pixel[2] != 0
}
for x in 0..width {
for y in 0..height {
let pixel = self.original.get_pixel(x, y);
if is_not_black(pixel) {
if left_x == 0 {
left_x = x;
}
if x >= right_x {
right_x = x;
}
}
}
}
if right_x == left_x {
panic!("找不到文字，可能是字体中不包含该文字");
}
(right_x - left_x, left_x)
}
}
#[cfg(test)]
mod tests {
use super::ImageCrop;
#[test]
fn test() {
let f = if std::path::Path::new("target").exists() {
"target/SourceHanSansSC-Bold.otf"
} else {
"../target/SourceHanSansSC-Bold.otf"
};
let font = std::fs::read(f).or_else( |_|{
tinyget::get("https://github.com/adobe-fonts/source-han-serif/raw/refs/heads/release/SubsetOTF/CN/SourceHanSerifCN-Bold.otf").send().map(|v|{
let s =v.as_bytes().to_vec();
println!("{} {:?}",s.len(),v.headers);
if &s.len().to_string() != v.headers.get("content-length").unwrap_or(&String::new()) && v.status_code !=200 {
panic!("字体文件下载失败");
}
let _ = std::fs::write(f, s.clone());
s
})
}).unwrap();
let font = ab_glyph::FontRef::try_from_slice(&font).unwrap();
let img = ImageCrop::new("的", 70, 120, &font);
let mut f = std::fs::File::create(if std::path::Path::new("target").exists() {
"target/single.jpeg"
} else {
"../target/single.jpeg"
})
.unwrap();
img.original
.write_to(&mut f, image::ImageFormat::Jpeg)
.unwrap();
println!("real_width {}", img.text_width().0);
}
}
}
#[cfg(feature = "cover")]
pub(crate) fn gen_cover(book_name: &str, font: &[u8]) -> IResult<Vec<u8>> {
use ab_glyph::{FontRef, PxScale};
use image::DynamicImage;
use text_width::ImageCrop;
let width = 150;
let height = 240;
let margin = 5;
let text = book_name;
let mut img = DynamicImage::new_rgb8(width, height);
let row_count;
let col_count;
if text.chars().count() % 3 == 0 {
col_count = 3;
row_count = (text.chars().count() / 3) as u32;
} else if text.chars().count() % 2 == 0 {
col_count = 2;
row_count = (text.chars().count() / 2) as u32;
} else {
col_count = 3.min(text.chars().count()) as u32;
row_count = 1.max((text.chars().count() as f32 / col_count as f32).ceil() as u32);
}
let use_width = (width - margin * 2) / col_count;
let use_height = (height - margin * 2) / row_count;
let sc = PxScale {
x: use_width as f32,
y: use_height as f32,
};
let font = FontRef::try_from_slice(font).unwrap();
for row in 0..row_count {
for col in 0..col_count {
let t = match text.chars().nth((row * col_count + col) as usize) {
Some(v) => v.to_string(),
None => break,
};
let crop = ImageCrop::new(t.as_str(), use_width, 120, &font);
let (real_width, begin_x) = crop.text_width();
let mut x = ((use_width - real_width) / 2) as i32;
x -= begin_x as i32;
x += margin as i32;
x += (col * use_width) as i32;
imageproc::drawing::draw_text_mut(
&mut img,
image::Rgba([255u8, 255u8, 255u8, 1u8]),
x,
(margin + row * use_height) as i32,
sc,
&font,
t.as_str(),
);
}
}
let mut buf = std::io::Cursor::new(Vec::new());
img.write_to(&mut buf, image::ImageFormat::Jpeg).unwrap();
Ok(buf.into_inner())
}
#[cfg(not(feature = "cover"))]
pub(crate) fn gen_cover(book_name: &str, font: &[u8]) -> IResult<Vec<u8>> {
panic!("自动封面需要启用 cover features")
}
#[cfg(all(test, feature = "cover"))]
mod tests {
#[test]
fn test_wqy() {
let z = "/usr/share/fonts/truetype/wqy/wqy-zenhei.ttc";
if !std::fs::metadata(z).map_or(false, |_| true) {
return;
}
println!("test sub overflow");
let font = std::fs::read(z).unwrap();
let m = super::gen_cover("测试括号（2024测试全集）", &font).unwrap();
std::fs::write(
if std::path::Path::new("target").exists() {
"target/cover5.jpeg"
} else {
"../target/cover5.jpeg"
},
m,
)
.unwrap();
}
#[test]
fn test_gen_cover() {
let f = if std::path::Path::new("target").exists() {
"target/SourceHanSansSC-Bold.otf"
} else {
"../target/SourceHanSansSC-Bold.otf"
};
let font = std::fs::read(f).or_else( |_|{
tinyget::get("https://github.com/adobe-fonts/source-han-serif/raw/refs/heads/release/SubsetOTF/CN/SourceHanSerifCN-Bold.otf").send().map(|v|{
let s =v.as_bytes().to_vec();
println!("{} {:?}",s.len(),v.headers);
if &s.len().to_string() != v.headers.get("content-length").unwrap_or(&String::new()) && v.status_code !=200 {
panic!("字体文件下载失败");
}
let _ = std::fs::write(f, s.clone());
s
})
}).unwrap();
let m = super::gen_cover("书名", &font).unwrap();
std::fs::write(
if std::path::Path::new("target").exists() {
"target/cover.jpeg"
} else {
"../target/cover.jpeg"
},
m,
)
.unwrap();
let m = super::gen_cover("每一个字都不同用来测试", &font).unwrap();
std::fs::write(
if std::path::Path::new("target").exists() {
"target/cover2.jpeg"
} else {
"../target/cover2.jpeg"
},
m,
)
.unwrap();
let m = super::gen_cover("的", &font).unwrap();
std::fs::write(
if std::path::Path::new("target").exists() {
"target/cover3.jpeg"
} else {
"../target/cover3.jpeg"
},
m,
)
.unwrap();
let m = super::gen_cover("大字", &font).unwrap();
std::fs::write(
if std::path::Path::new("target").exists() {
"target/cover4.jpeg"
} else {
"../target/cover4.jpeg"
},
m,
)
.unwrap();
}
}