Finish image error handling w/ magick

cowgen/Cargo.toml

@@ -8,3 +8,4 @@ edition = "2021"
 
 [dependencies]
 ril = { version = "0", features = ["all"] }
+magick_rust = { version = "0.16" }

cowgen/src/lib.rs

@@ -1,27 +1,43 @@
+use magick_rust::{magick_wand_genesis, MagickError, MagickWand};
 use ril::prelude::*;
+use std::sync::Once;
 use std::{fs::File, path::Path};
 
+// Used to make sure MagickWand is initialized exactly once. Note that we
+// do not bother shutting down, we simply exit when we're done.
+static START: Once = Once::new();
+
 pub struct Template<T: AsRef<str>, V: AsRef<Path>> {
     elements: Vec<Element<T, V>>,
-    dimensions: (u32, u32),
-    base: Image,
+    base: Image<Rgba>,
 }
 
 impl<T: AsRef<str>, V: AsRef<Path>> Template<T, V> {
     pub fn new(base: Vec<u8>, elements: Vec<Element<T, V>>) -> Result<Self, CowError> {
-        let base: Image<Dynamic> = Image::from_bytes_inferred(base)?;
         Ok(Self {
-            dimensions: base.dimensions(),
+            base: match Image::<Rgba>::from_bytes_inferred(&base) {
+                Ok(img) => img,
+                _ => {
+                    START.call_once(|| {
+                        magick_wand_genesis();
+                    });
+                    let mut wand = MagickWand::new();
+                    wand.read_image_blob(&base)?;
+                    wand.set_format("png32")?;
+                    let base = wand.write_image_blob("png")?;
+                    Image::from_bytes_inferred(base)?
+                }
+            },
             elements,
-            base,
         })
     }
 
-    pub fn produce(mut self) -> Vec<u8> {
+    pub fn produce(self) -> Result<Vec<u8>, CowError> {
         let size = self.base.dimensions();
+        let mut base_image = self.base.with_overlay_mode(OverlayMode::Merge);
         for element in self.elements {
             let mut pos = element.position;
-            let mut img: Image = element.into();
+            let mut img: Image = element.into_image()?;
             if pos.0 < 0 {
                 img.crop(-pos.0 as u32, 0, size.0, size.1);
                 pos.0 = 0;
@@ -31,13 +47,12 @@ impl<T: AsRef<str>, V: AsRef<Path>> Template<T, V> {
                 pos.1 = 0;
             }
 
-            self.base
-                .draw(&Paste::new(img).with_position(pos.0 as u32, pos.1 as u32));
+            base_image.draw(&Paste::new(img.convert()).with_position(pos.0 as u32, pos.1 as u32));
         }
         let mut buf = Vec::<u8>::new();
-        self.base.encode(ImageFormat::Png, &mut buf).unwrap();
+        base_image.encode(ImageFormat::Png, &mut buf).unwrap();
 
-        buf
+        Ok(buf)
     }
 }
 
@@ -55,17 +70,15 @@ impl<T: AsRef<str>, V: AsRef<Path>> Element<T, V> {
             media,
         }
     }
-}
 
-impl<T: AsRef<str>, V: AsRef<Path>> Into<Image> for Element<T, V> {
-    fn into(self) -> Image {
+    fn into_image(self) -> Result<Image, CowError> {
         match self.media {
-            Media::Image(image) => image.resized(
+            Media::Image(image) => Ok(Image::from_bytes_inferred(image)?.resized(
                 self.dimensions.0,
                 self.dimensions.1,
                 ResizeAlgorithm::Bicubic,
-            ),
-            Media::Text(text) => Image::new(
+            )),
+            Media::Text(text) => Ok(Image::new(
                 self.dimensions.0,
                 self.dimensions.1,
                 Dynamic::Rgba(Rgba::transparent()),
@@ -74,28 +87,33 @@ impl<T: AsRef<str>, V: AsRef<Path>> Into<Image> for Element<T, V> {
                 &TextSegment::new(
                     &Font::from_reader(File::open(text.font).unwrap(), 12.0).unwrap(),
                     text.text,
-                    Dynamic::Rgb(Rgb::new(text.fill.0, text.fill.1, text.fill.2)),
+                    Dynamic::Rgba(Rgba::new(
+                        text.fill.0,
+                        text.fill.1,
+                        text.fill.2,
+                        text.fill.3,
+                    )),
                 )
                 .with_size(text.size),
-            ),
+            )),
         }
     }
 }
 
 pub enum Media<T: AsRef<str>, V: AsRef<Path>> {
     Text(Text<T, V>),
-    Image(Image),
+    Image(Vec<u8>),
 }
 
 pub struct Text<T: AsRef<str>, V: AsRef<Path>> {
     text: T,
     font: V,
     size: f32,
-    fill: (u8, u8, u8),
+    fill: (u8, u8, u8, u8),
 }
 
 impl<T: AsRef<str>, V: AsRef<Path>> Text<T, V> {
-    pub fn new(text: T, font: V, size: f32, fill: (u8, u8, u8)) -> Self {
+    pub fn new(text: T, font: V, size: f32, fill: (u8, u8, u8, u8)) -> Self {
         Self {
             text,
             font,
@@ -107,6 +125,7 @@ impl<T: AsRef<str>, V: AsRef<Path>> Text<T, V> {
 
 #[derive(Clone, Debug)]
 pub enum CowError {
+    Magick(String),
     Other(String),
 }
 
@@ -116,6 +135,12 @@ impl From<ril::Error> for CowError {
     }
 }
 
+impl From<MagickError> for CowError {
+    fn from(m: MagickError) -> Self {
+        CowError::Magick(m.0.to_owned())
+    }
+}
+
 #[cfg(test)]
 mod tests {
     #[test]

cowmic/src/main.rs

@@ -4,20 +4,27 @@ use cowgen::{CowError, Element, Text};
 
 fn main() -> Result<(), CowError> {
     let out = cowgen::Template::new(
-        include_bytes!("cow2.png").to_vec(),
-        vec![Element::new(
+        include_bytes!("cow.png").to_vec(),
+        vec![
+            Element::new(
                 cowgen::Media::Text(Text::new(
                     "Hello",
                     "/usr/share/fonts/TTF/OpenSans-ExtraBold.ttf",
-                12.0,
-                (0, 0, 0),
+                    20.0,
+                    (0, 0, 0, 128),
                 )),
                 (0, 0),
                 (64, 64),
-        )],
+            ),
+            Element::new(
+                cowgen::Media::Image(include_bytes!("mariah.jpg").to_vec()),
+                (200, 400),
+                (800, 200),
+            ),
+        ],
     )?
-    .produce();
-    let mut f = File::create("out.png").unwrap();
+    .produce()?;
+    let mut f = File::create("out2.png").unwrap();
     f.write_all(&out).unwrap();
     f.flush().unwrap();
     Ok(())