pdfcraft/crates/fonts/build.rs

56 lines
2.7 KiB
Rust

//! Embeds the fonts of the optional craft-fonts build input (`CRAFT_FONTS_DIR`) as `CRAFT_FONTS`.
//! The recipe is craft-fonts' `docs/integration.md`; unset, `CRAFT_FONTS` is empty. It only reads
//! the local checkout (no network). On wasm32 it embeds only the UI face (BIZ UDPGothic Regular),
//! to keep the web build within hosting limits (Cloudflare Pages: 25 MiB per file).
use std::fmt::Write as _;
use std::path::PathBuf;
fn main() {
println!("cargo::rerun-if-env-changed=CRAFT_FONTS_DIR");
println!("cargo::rerun-if-env-changed=CRAFT_FONTS_REQUIRED");
let mut src = String::from("pub static CRAFT_FONTS: &[CraftFont] = &[\n");
if let Some(dir) = std::env::var_os("CRAFT_FONTS_DIR").map(PathBuf::from) {
match craft_fonts(&dir) {
Ok(entries) => src.push_str(&entries),
Err(e) if std::env::var_os("CRAFT_FONTS_REQUIRED").is_some() => {
println!("cargo::error=CRAFT_FONTS_DIR={}: {e}", dir.display());
}
Err(e) => println!("cargo::warning=building without craft-fonts: CRAFT_FONTS_DIR={}: {e}", dir.display()),
}
}
src.push_str("];\n");
let out = PathBuf::from(std::env::var_os("OUT_DIR").unwrap_or_default()).join("craft_fonts.rs");
if let Err(e) = std::fs::write(&out, src) {
println!("cargo::error=writing {}: {e}", out.display());
}
}
/// One `CraftFont { .. }` initialiser per manifest line.
fn craft_fonts(dir: &std::path::Path) -> Result<String, String> {
let manifest = dir.join("fonts/manifest.txt");
println!("cargo::rerun-if-changed={}", manifest.display());
let text = std::fs::read_to_string(&manifest).map_err(|e| format!("{}: {e}", manifest.display()))?;
let wasm = std::env::var("CARGO_CFG_TARGET_ARCH").is_ok_and(|a| a == "wasm32");
let mut out = String::new();
for line in text.lines().map(str::trim).filter(|l| !l.is_empty() && !l.starts_with('#')) {
let f: Vec<&str> = line.split(" | ").map(str::trim).collect();
let [family, style, file, scripts, ..] = f.as_slice() else {
return Err(format!("malformed manifest line: {line}"));
};
if wasm && !(*family == "BIZ UDPGothic" && *style == "Regular") {
continue;
}
let path = dir.join(file).canonicalize().map_err(|e| format!("{file}: {e}"))?;
println!("cargo::rerun-if-changed={}", path.display());
let scripts: Vec<String> = scripts.split(',').map(|s| format!("{:?}", s.trim())).collect();
let _ = writeln!(
out,
" CraftFont {{ family: {family:?}, style: {style:?}, scripts: &[{}], bytes: include_bytes!({:?}) }},",
scripts.join(", "),
path.display().to_string(),
);
}
Ok(out)
}