Finish image error handling w/ magick

README.md

@@ -1,3 +1,5 @@
 # cowmic
 
 generates memes
+
+`mogrify -define png:format=png32 -format png *.png`

cowgen/Cargo.toml

@@ -7,3 +7,5 @@ edition = "2021"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+ril = { version = "0", features = ["all"] }
+magick_rust = { version = "0.16" }

cowgen/src/lib.rs

@@ -1,3 +1,146 @@
+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>>,
+    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> {
+        Ok(Self {
+            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,
+        })
+    }
+
+    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_image()?;
+            if pos.0 < 0 {
+                img.crop(-pos.0 as u32, 0, size.0, size.1);
+                pos.0 = 0;
+            }
+            if pos.1 < 0 {
+                img.crop(0, -pos.1 as u32, size.0, size.1);
+                pos.1 = 0;
+            }
+
+            base_image.draw(&Paste::new(img.convert()).with_position(pos.0 as u32, pos.1 as u32));
+        }
+        let mut buf = Vec::<u8>::new();
+        base_image.encode(ImageFormat::Png, &mut buf).unwrap();
+
+        Ok(buf)
+    }
+}
+
+pub struct Element<T: AsRef<str>, V: AsRef<Path>> {
+    position: (i32, i32),
+    dimensions: (u32, u32),
+    media: Media<T, V>,
+}
+
+impl<T: AsRef<str>, V: AsRef<Path>> Element<T, V> {
+    pub fn new(media: Media<T, V>, position: (i32, i32), dimensions: (u32, u32)) -> Self {
+        Self {
+            position,
+            dimensions,
+            media,
+        }
+    }
+
+    fn into_image(self) -> Result<Image, CowError> {
+        match self.media {
+            Media::Image(image) => Ok(Image::from_bytes_inferred(image)?.resized(
+                self.dimensions.0,
+                self.dimensions.1,
+                ResizeAlgorithm::Bicubic,
+            )),
+            Media::Text(text) => Ok(Image::new(
+                self.dimensions.0,
+                self.dimensions.1,
+                Dynamic::Rgba(Rgba::transparent()),
+            )
+            .with(
+                &TextSegment::new(
+                    &Font::from_reader(File::open(text.font).unwrap(), 12.0).unwrap(),
+                    text.text,
+                    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(Vec<u8>),
+}
+
+pub struct Text<T: AsRef<str>, V: AsRef<Path>> {
+    text: T,
+    font: V,
+    size: f32,
+    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, u8)) -> Self {
+        Self {
+            text,
+            font,
+            size,
+            fill,
+        }
+    }
+}
+
+#[derive(Clone, Debug)]
+pub enum CowError {
+    Magick(String),
+    Other(String),
+}
+
+impl From<ril::Error> for CowError {
+    fn from(r: ril::Error) -> Self {
+        CowError::Other(r.to_string())
+    }
+}
+
+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

@@ -1,3 +1,31 @@
-fn main() {
-    println!("Hello, world!");
+use std::{fs::File, io::Write};
+
+use cowgen::{CowError, Element, Text};
+
+fn main() -> Result<(), CowError> {
+    let out = cowgen::Template::new(
+        include_bytes!("cow.png").to_vec(),
+        vec![
+            Element::new(
+                cowgen::Media::Text(Text::new(
+                    "Hello",
+                    "/usr/share/fonts/TTF/OpenSans-ExtraBold.ttf",
+                    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("out2.png").unwrap();
+    f.write_all(&out).unwrap();
+    f.flush().unwrap();
+    Ok(())
 }