Ajoute pmocovers

pmocovers/src/webp.rs

@@ -0,0 +1,61 @@
+use anyhow::Result;
+use image::{DynamicImage, imageops::FilterType};
+use webp::{Encoder, WebPMemory};
+
+pub fn encode_webp(img: &DynamicImage) -> Result<Vec<u8>> {
+    let rgb_img = img.to_rgba8();
+    let encoder = Encoder::from_rgba(&rgb_img, rgb_img.width(), rgb_img.height());
+    let webp_data: WebPMemory = encoder.encode(85.0);
+    Ok(webp_data.to_vec())
+}
+
+pub fn ensure_square(img: &DynamicImage, size: u32) -> DynamicImage {
+    let (width, height) = (img.width(), img.height());
+    
+    // Calculer le ratio de mise à l'échelle
+    let scale = if width > height {
+        size as f32 / width as f32
+    } else {
+        size as f32 / height as f32
+    };
+    
+    let new_width = (width as f32 * scale) as u32;
+    let new_height = (height as f32 * scale) as u32;
+    
+    // Redimensionner l'image
+    let resized = img.resize(new_width, new_height, FilterType::Lanczos3);
+    
+    // Créer une image carrée avec fond transparent
+    let mut square = DynamicImage::new_rgba8(size, size);
+    
+    // Calculer la position pour centrer l'image redimensionnée
+    let x = (size - new_width) / 2;
+    let y = (size - new_height) / 2;
+    
+    // Copier l'image redimensionnée au centre du carré
+    image::imageops::overlay(&mut square, &resized, x.into(), y.into());
+    
+    square
+}
+
+pub async fn generate_variant(cache: &super::cache::Cache, pk: &str, size: usize) -> Result<Vec<u8>> {
+    let variant_path = cache.dir.join(format!("{}.{}.webp", pk, size));
+
+    if variant_path.exists() {
+        return Ok(tokio::fs::read(variant_path).await?);
+    }
+
+    let orig_path = cache.dir.join(format!("{}.orig.webp", pk));
+
+    // Charger l'image de manière synchrone (image::open n'est pas async)
+    let img = tokio::task::spawn_blocking(move || {
+        image::open(orig_path)
+    })
+    .await??;
+
+    let square = ensure_square(&img, size as u32);
+    let webp_data = encode_webp(&square)?;
+
+    tokio::fs::write(&variant_path, &webp_data).await?;
+    Ok(webp_data)
+}