103 lines
2.7 KiB
Rust
103 lines
2.7 KiB
Rust
use std::path::{Path, PathBuf};
|
|
|
|
use image::codecs::jpeg::JpegEncoder;
|
|
use image::imageops::FilterType;
|
|
|
|
#[derive(Debug, Clone, Copy)]
|
|
pub struct CoverVariant {
|
|
pub name: &'static str,
|
|
pub max_edge: u32,
|
|
pub quality: u8,
|
|
}
|
|
|
|
pub const COVER_VARIANTS: &[CoverVariant] = &[
|
|
CoverVariant {
|
|
name: "small",
|
|
max_edge: 96,
|
|
quality: 80,
|
|
},
|
|
CoverVariant {
|
|
name: "medium",
|
|
max_edge: 256,
|
|
quality: 82,
|
|
},
|
|
CoverVariant {
|
|
name: "large",
|
|
max_edge: 512,
|
|
quality: 85,
|
|
},
|
|
];
|
|
|
|
pub fn variant_by_name(name: &str) -> Option<CoverVariant> {
|
|
COVER_VARIANTS
|
|
.iter()
|
|
.copied()
|
|
.find(|variant| variant.name == name)
|
|
}
|
|
|
|
pub fn variant_path(original_path: &Path, variant: CoverVariant) -> PathBuf {
|
|
let stem = original_path
|
|
.file_stem()
|
|
.and_then(|value| value.to_str())
|
|
.filter(|value| !value.is_empty())
|
|
.unwrap_or("cover");
|
|
let filename = format!("{stem}.{}.jpg", variant.name);
|
|
original_path.with_file_name(filename)
|
|
}
|
|
|
|
pub fn missing_variants(original_path: &Path) -> Vec<CoverVariant> {
|
|
COVER_VARIANTS
|
|
.iter()
|
|
.copied()
|
|
.filter(|variant| !variant_path(original_path, *variant).exists())
|
|
.collect()
|
|
}
|
|
|
|
pub async fn ensure_cover_variants(original_path: &Path) -> anyhow::Result<usize> {
|
|
let missing = missing_variants(original_path);
|
|
if missing.is_empty() {
|
|
return Ok(0);
|
|
}
|
|
|
|
let original_path = original_path.to_path_buf();
|
|
tokio::task::spawn_blocking(move || generate_missing_variants_sync(&original_path, &missing))
|
|
.await
|
|
.map_err(|err| anyhow::anyhow!("cover variant task failed: {err}"))?
|
|
}
|
|
|
|
fn generate_missing_variants_sync(
|
|
original_path: &Path,
|
|
variants: &[CoverVariant],
|
|
) -> anyhow::Result<usize> {
|
|
let data = std::fs::read(original_path)?;
|
|
let image = image::load_from_memory(&data)?;
|
|
|
|
let mut created = 0usize;
|
|
for variant in variants {
|
|
let path = variant_path(original_path, *variant);
|
|
if path.exists() {
|
|
continue;
|
|
}
|
|
|
|
if let Some(parent) = path.parent() {
|
|
std::fs::create_dir_all(parent)?;
|
|
}
|
|
|
|
let resized = image
|
|
.resize(variant.max_edge, variant.max_edge, FilterType::Lanczos3)
|
|
.to_rgb8();
|
|
let mut output = Vec::new();
|
|
let mut encoder = JpegEncoder::new_with_quality(&mut output, variant.quality);
|
|
encoder.encode(
|
|
&resized,
|
|
resized.width(),
|
|
resized.height(),
|
|
image::ExtendedColorType::Rgb8,
|
|
)?;
|
|
std::fs::write(path, output)?;
|
|
created += 1;
|
|
}
|
|
|
|
Ok(created)
|
|
}
|